Prescription 2016: Better Brain FunctionFebruary 8, 2016 Written by JP [Font too small?]
One of the ironies of life is that we are often called on to perform at our very best during the busiest, most stressful times. This is understandable from a pragmatic, rational standpoint. Simply put, we do what’s required as best we can. But, that’s not to say that there aren’t tools available to help our brains adapt to such intense challenges.
The alternative and complementary therapies listed below provide a long list of health benefits. This is important to note because hectic times often result in poor self-care. Diets tend to go out the window. Exercise routines fall by the wayside. And, sleep may become irregular due to overthinking or time constraints. All of these problems are real, but so are these solutions.
Using Diet Strategically: Maintaining a nutrient-dense diet can assist cognition and mood during times of physical and psychological stress. According to the scientific literature, a Mediterranean-style diet is associated with improved alertness, contentedness and reduced confusion. What’s more, the rewards present themselves within ten days of practice. Based on a number of separate studies, I suspect that the inclusion of cold water fish may explain some of these cognitive benefits. Staying well hydrated and ending meals with dark chocolate further complement a healthy diet by decreasing mental fatigue, while providing timely neuroprotection. To this end, I look for organic dark chocolate bars that contain a minimum of 70% cacao content and less than 10 grams of sugar per serving.
Day and Night Supplements: If you’re seeking occasional daytime brain support consider Cereboost, a patented extract of American ginseng. Acute 100-200 mg doses of Cereboost are documented as enhancing feelings of “calmness”, supporting “reaction time accuracy” and working memory. At nighttime, pure cherry juice can be of value. A recent, 12-week study in the European Journal of Nutrition reports that 200 ml/day (about 7 ounces) improves long-term memory, short-term memory and verbal fluency in older adults. A statistically significant decline in blood pressure was evidenced as well. As an added bonus, cherry juice is capable of diminishing anxiety and enhancing sleep quality – two factors that profoundly influence cognition and mood.
Mind Your Body: Mindfulness meditation is an excellent option for on-going and periodic brain support. A study published in May 2015 revealed that even one week of mindfulness training prevents “stress related working memory impairments”. Those who practice mindfulness for longer periods of time (one month or more) display even greater changes in cognitive functions and psychological stress response. Aromatherapy can be used alongside or independent of meditation and other mind-body approaches. Specifically, peppermint and sage oil positively affect alertness and quality of memory. That’s why I have a bottle of peppermint oil sitting next to me on my desk. I put a few drops on a tissue and inhale the stimulating scent whenever I need a mental boost.
My final suggestion is a spin-off of the aforementioned mind-body remedies. When you feel overwhelmed by life, take a moment to laugh. I realize that “taking a moment” when you’re already pressed for time seems counter-intuitive. However, it’s a wise investment. Taking a half-hour (or less) off to laugh and smile is powerful medicine. In fact, experiments reveal that watching a 20 minute, humorous video imparts many cognitive advantages, including improved learning ability, recall and visual recognition. At the same time, stress hormone levels plummet in those who take a brief laughter break. This, in essence, refreshes your brain and allows you to function at much higher level. Employers take note!
Note: Please check out the “Comments & Updates” section of this blog – at the bottom of the page. You can find the latest research about this topic there!
To learn more about the studies referenced in today’s column, please click on the following links:
Study 1 – Switching to a 10-day Mediterranean-Style Diet Improves Mood … (link)
Study 2 – Effects of Beverages with Variable Nutrients on Rehydration and … (link)
Study 3 – Effects of Drinking Supplementary Water at School on Cognitive … (link)
Study 4 – Omega-3 Fatty Acids Moderate Effects of Physical Activity on … (link)
Study 5 – DHA Supplementation Improved Both Memory and Reaction Time … (link)
Study 6 – Acute & Sub-Chronic Effects of Cocoa Flavanols on Mood, Cognitive … (link)
Study 7 – Cocoa Flavanol Consumption Improves Cognitive Function, Blood … (link)
Study 8 – Flavonol-Rich Dark Cocoa Significantly Decreases Plasma Endothelin-1 … (link)
Study 9 – Improved Working Memory Performance Following Administration … (link)
Study 10 – Effects of American Ginseng (Panax Quinquefolius) on Neurocognitive … (link)
Study 11 – Consumption of Anthocyanin-Rich Cherry Juice for 12 Weeks Improves … (link)
Study 12 – Consumption of a Jerte Valley Cherry Product in Humans Enhances … (link)
Study 13 – A Jerte Valley Cherry Product Provides Beneficial Effects on Sleep … (link)
Study 14 – Cognitive Performance, Sleepiness, and Mood in Partially Sleep … (link)
Study 15 – Add-On Prolonged-Release Melatonin for Cognitive Function and … (link)
Study 16 – Randomized Controlled Trial Examining the Effect of Mindfulness … (link)
Study 17 – The Protective Effects of Brief Mindfulness Meditation Training … (link)
Study 18 – Immediate and Long-Term Effects of Meditation on Acute Stress … (link)
Study 19 – Differential Effects of the Aromas of Salvia Species on Memory and … (link)
Study 20 – Modulation of Cognitive Performance & Mood by Aromas of Peppermint … (link)
Study 21 – Humors Effect on Short-term Memory in Healthy and Diabetic Older … (link)
Study 22 – The Effect of Humor on Short-Term Memory in Older Adults: A New … (link)
Phytochemicals May Benefit Brain Function & Health
Source: Front Aging Neurosci. 2015; 7: 132. (link)
Tags: Chocolate, Laughter, Meditation
Posted in Alternative Therapies, Memory, Nutritional Supplements
February 8th, 2016 at 4:17 pm
J Relig Health. 2016 Feb 5.
Effect of a Single Session of a Yogic Meditation Technique on Cognitive Performance in Medical Students: A Randomized Crossover Trial.
Medical students confront enormous academic, psychosocial, and existential stress throughout their training, leading to a cascade of consequences both physically and psychologically. The declined cognitive function of these students interferes in their academic performance and excellence. The purpose of this study was to examine the effectiveness of a yogic meditation technique, mind sound resonance technique (MSRT), on cognitive functions of University Medical students in a randomized, two-way crossover study. In total, 42 healthy volunteers of both genders (5 males and 37 females) with mean age of 19.44 ± 1.31 years were recruited from a medical college in South India, based on the inclusion and exclusion criteria. A 10-day orientation in the technique of MSRT was given to all the recruited subjects after which each subject underwent both MSRT and supine rest (SR) sessions. All participants were randomized in a 1:1 ratio to receive a session of either MSRT or SR. After a day of washout, participants crossed over to receive the alternative intervention. The cognitive functions were assessed using 2 paper-pencil tasks called Digit Letter Substitution Test (DLST) and Six-Letter Cancelation Task (SLCT), before and immediately after both sessions. Both the groups showed significant improvement in net attempt of both DLST and SLCT, but the magnitude of change was more in the MSRT group than in the SR group. The MSRT group demonstrated significantly enhanced net scores in both SLCT (p < 0.001) and DLST (p < 0.001). The result of the present study suggests that a single session of MSRT, a Mind-Body Practice, may positively impact the performance in cognitive tasks by the University Medical Students. Be well! JP
February 8th, 2016 at 4:18 pm
Front Psychol. 2016 Jan 19;6:2043.
Does Mindfulness Enhance Critical Thinking? Evidence for the Mediating Effects of Executive Functioning in the Relationship between Mindfulness and Critical Thinking.
Mindfulness originated in the Buddhist tradition as a way of cultivating clarity of thought. Despite the fact that this behavior is best captured using critical thinking (CT) assessments, no studies have examined the effects of mindfulness on CT or the mechanisms underlying any such possible relationship. Even so, mindfulness has been suggested as being beneficial for CT in higher education. CT is recognized as an important higher-order cognitive process which involves the ability to analyze and evaluate evidence and arguments. Such non-automatic, reflective responses generally require the engagement of executive functioning (EF) which includes updating, inhibition, and shifting of representations in working memory. Based on research showing that mindfulness enhances aspects of EF and certain higher-order cognitive processes, we hypothesized that individuals higher in facets of dispositional mindfulness would demonstrate greater CT performance, and that this relationship would be mediated by EF. Cross-sectional assessment of these constructs in a sample of 178 university students was achieved using the observing and non-reactivity sub-scales of the Five Factor Mindfulness Questionnaire, a battery of EF tasks and the Halpern Critical Thinking Assessment. Our hypotheses were tested by constructing a multiple meditation model which was analyzed using Structural Equation Modeling. Evidence was found for inhibition mediating the relationships between both observing and non-reactivity and CT in different ways. Indirect-only (or full) mediation was demonstrated for the relationship between observing, inhibition, and CT. Competitive mediation was demonstrated for the relationship between non-reactivity, inhibition, and CT. This suggests additional mediators of the relationship between non-reactivity and CT which are not accounted for in this model and have a negative effect on CT in addition to the positive effect mediated by inhibition. These findings are discussed in the context of the Default Interventionist Dual Process Theory of Higher-order Cognition and previous studies on mindfulness, self-regulation, EF, and higher-order cognition. In summary, dispositional mindfulness appears to facilitate CT performance and this effect is mediated by the inhibition component of EF. However, this relationship is not straightforward which suggests many possibilities for future research.
February 8th, 2016 at 4:19 pm
BMC Public Health. 2015 Dec 16;15:1245.
Open and Calm–a randomized controlled trial evaluating a public stress reduction program in Denmark.
BACKGROUND: Prolonged psychological stress is a risk factor for illness and constitutes an increasing public health challenge creating a need to develop public interventions specifically targeting stress and promoting mental health. The present randomized controlled trial evaluated health effects of a novel program: Relaxation-Response-based Mental Health Promotion (RR-MHP).
METHODS: The multimodal, meditation-based course was publicly entitled “Open and Calm” (OC) because it consistently trained relaxed and receptive (“Open”) attention, and consciously non-intervening (“Calm”) witnessing, in two standardized formats (individual or group) over nine weeks. Seventy-two participants who complained to their general practitioner about reduced daily functioning due to prolonged stress or who responded to an online health survey on stress were randomly assigned to OC formats or treatment as usual, involving e.g., unstandardized consultations with their general practitioner. Outcomes included perceived stress, depressive symptoms, quality of life, sleep disturbances, mental health, salivary cortisol, and visual perception. Control variables comprised a genetic stress-resiliency factor (serotonergic transporter genotype; 5-HTTLPR), demographics, personality, self-reported inattentiveness, and course format.
RESULTS: Intent-to-treat analyses showed significantly larger improvements in OC than in controls on all outcomes. Treatment effects on self-reported outcomes were sustained after 3 months and were not related to age, gender, education, or course format. The dropout rate was only 6 %.
CONCLUSIONS: The standardized OC program reduced stress and improved mental health for a period of 3 months. Further testing of the OC program for public mental health promotion and reduction of stress-related illnesses is therefore warranted. A larger implementation is in progress.
February 11th, 2016 at 10:00 pm
This article looks to me like a valuable package of alternative medicine natural remedies extremely valuable to defend our our brains from the attacks of the ever increasing stresses of the modern world we live in. Many of these tools are side effect free and within our reach.
Thank you for sharing these valuable tools with us, your loyal followers!
Keep up your great work!
February 11th, 2016 at 10:43 pm
Thank you, Paul! I appreciate your support!
February 11th, 2016 at 10:51 pm
Recently, a reader got in touch with me about potential ginseng interactions with common medications such anticoagulants. At least one study suggests this is a possibility:
Combining medications and supplements can be challenging. But, it can often be done safely … if it’s done thoughtfully. I urge all my clients and readers to consult with their pharmacists and physicians prior to adding new supplements to their health care routine.
February 14th, 2016 at 5:35 pm
Am J Clin Nutr. 2016 Feb 10.
Concord grape juice, cognitive function, and driving performance: a 12-wk, placebo-controlled, randomized crossover trial in mothers of preteen children.
BACKGROUND: Daily consumption of Concord grape juice (CGJ) over 3-4 mo has been shown to improve memory function in adults with mild cognitive impairment and reduce blood pressure in hypertensive adults. These benefits likely result from the high concentration of polyphenols in CGJ. Increased stress can impair cognitive function and elevate blood pressure. Thus, we examined the potential beneficial effect of CGJ in individuals with somewhat stressful and demanding lifestyles.
OBJECTIVE: We sought to examine the effects of the daily consumption of CGJ for 12 wk on cognitive function, driving performance, and blood pressure in healthy, middle-aged working mothers.
DESIGN: Twenty-five healthy mothers (aged 40-50 y) of preteen children who were employed for ≥30 h/wk consumed 12 ounces (355 mL) of either CGJ (containing 777 mg total polyphenols) or an energy-, taste-, and appearance-matched placebo daily for 12 wk according to a randomized crossover design with a 4-wk washout. Verbal and spatial memory, executive function, attention, blood pressure, and mood were assessed at baseline and at 6 and 12 wk. Immediately after the cognitive battery, a subsample of 17 women completed a driving performance assessment at the University of Leeds Driving Simulator. The 25-min driving task required participants to match the speed and direction of a lead vehicle.
RESULTS: Significant improvements in immediate spatial memory and driving performance were observed after CGJ relative to placebo. There was evidence of an enduring effect of CGJ such that participants who received CGJ in arm 1 maintained better performance in the placebo arm.
CONCLUSIONS: Cognitive benefits associated with the long-term consumption of flavonoid-rich grape juice are not exclusive to adults with mild cognitive impairment. Moreover, these cognitive benefits are apparent in complex everyday tasks such as driving. Effects may persist beyond the cessation of flavonoid consumption, and future studies should carefully consider the length of washout within crossover designs.
February 22nd, 2016 at 6:32 pm
J Nurs Scholarsh. 2016 Feb 15.
Effects of Multivitamin Supplements on Cognitive Function, Serum Homocysteine Level, and Depression of Korean With Mild Cognitive Impairment in Care Facilities.
PURPOSE: To examine effects of multivitamin supplements on cognitive function, serum homocysteine level, and depression of Korean older adults with mild cognitive impairment (MCI) in care facilities.
DESIGN: A quasi-experimental pretest-posttest control group design was employed.
METHODS: Forty-eight adults 65 years of age and older with MCI (experimental, n = 24; control, n = 24) who were living in care facilities in Gyeong-gi-do, Korea, were recruited. Multivitamin supplements as experimental treatment consisted of vitamin B6, B12, and folic acid. Multivitamin supplements were taken at a dosage of one pill every day for 12 weeks through the oral route. Measures were Mini Mental State Examination-Korean, serum homocysteine level, and Geriatric Depression Scale Short Form Korea Version. Collected data were analyzed using SPSS version 21.0 statistical software (SPSS Inc., Chicago, IL, USA).
FINDINGS: There were significant effects of multivitamin supplements on cognitive function (F = 3.624, p = .021), serum homocysteine level (F = 6.974, p = .001), and depression (F = 10.849, p = .001).
CONCLUSIONS: Multivitamin supplements increased cognitive function, and decreased serum homocysteine level and depression of Korean older adults with MCI in care facilities.
CLINICAL RELEVANCE: Multivitamin supplements can be utilized for improving cognitive ability and for decreasing depression of Korean older adults with MCI in care facilities.
February 26th, 2016 at 2:30 pm
Sultan Qaboos Univ Med J. 2016 Feb;16(1):e47-53.
Effectiveness of a Combined Dance and Relaxation Intervention on Reducing Anxiety and Depression and Improving Quality of Life among the Cognitively Impaired Elderly.
OBJECTIVES: Cognitive impairment is a common problem among the elderly and is believed to be a precursor to dementia. This study aimed to explore the effectiveness of a combined dance and relaxation intervention as compared to relaxation alone in reducing anxiety and depression levels and improving quality of life (QOL) and cognitive function among the cognitively impaired elderly.
METHODS: This quasi-experimental study was conducted between May and December 2013 in Peninsular Malaysia. Subjects from four government residential homes for older adults aged ≥60 years with mild to moderate cognitive function as assessed by the Mini-Mental State Examination were included in the study. Subjects were divided into an intervention group and a control group; the former participated in a combined poco-poco dance and relaxation intervention whilst the latter participated in relaxation exercises only. Both groups participated in two sessions per week for six weeks. Anxiety and depression were self-assessed using the Hospital Anxiety and Depression Scale and QOL was self-assessed using the Quality of Life in Alzheimer’s Disease questionnaire.
RESULTS: A total of 84 elderly subjects were included in the study; 44 were in the intervention group and 40 were in the control group. When compared to control subjects, those in the intervention group showed significantly decreased anxiety (P <0.001) and depression (P <0.001) levels as well as improved QOL (P <0.001) and cognitive impairment (P <0.001).
CONCLUSION: Dance as a form of participation-based physical exercise was found to reduce anxiety and depression levels and improve QOL and cognitive function among the studied sample of cognitively impaired elderly subjects in Malaysia.
March 18th, 2016 at 7:17 pm
Adv Exp Med Biol. 2016;876:319-25. doi: 10.1007/978-1-4939-3023-4_40.
Effect of the Antioxidant Supplement Pyrroloquinoline Quinone Disodium Salt (BioPQQ™) on Cognitive Functions.
Pyrroloquinoline quinone (PQQ) is a quinone compound first identified in 1979. It has been reported that rats fed a PQQ-supplemented diet showed better learning ability than controls, suggesting that PQQ may be useful for improving memory in humans. In the present study, a randomized, placebo-controlled, double-blinded study to examine the effect of PQQ disodium salt (BioPQQ™) on cognitive functions was conducted with 41 elderly healthy subjects. Subjects were orally given 20 mg of BioPQQ™ per day or placebo, for 12 weeks. For cognitive functions, selective attention by the Stroop and reverse Stroop test, and visual-spatial cognitive function by the laptop tablet Touch M, were evaluated. In the Stroop test, the change of Stroop interference ratios (SIs) for the PQQ group was significantly smaller than for the placebo group. In the Touch M test, the stratification analyses dividing each group into two groups showed that only in the lower group of the PQQ group (initial score < 70), did the score significantly increase. Measurements of physiological parameters indicated no abnormal blood or urinary adverse events, nor adverse internal or physical examination findings at any point in the study. The preliminary experiment using near-infrared spectrometry (NIRS) suggests that cerebral blood flow in the prefrontal cortex was increased by the administration of PQQ. The results suggest that PQQ can prevent reduction of brain function in aged persons, especially in attention and working memory. Be well! JP
May 27th, 2016 at 7:23 pm
Fam Process. 2016 May 26.
Mindful Mates: A Pilot Study of the Relational Effects of Mindfulness-Based Stress Reduction on Participants and Their Partners.
Very little is currently known about how increases in dispositional mindfulness through mindfulness training affect the quality of participants’ romantic relationships, and no previous studies have examined how increases in specific facets of mindfulness differentially contribute to relationship health. Additionally, even less is known about how an individual’s development of mindfulness skills affects the relationship satisfaction of his or her romantic partner. Thus, the purpose of this pilot study was to examine associations between changes in facets of mindfulness and relationship satisfaction among participants enrolled in a Mindfulness-Based Stress Reduction (MBSR) course and their nonenrolled romantic partners. Twenty MBSR participants and their nonenrolled partners (n = 40) completed measures of mindfulness and relationship satisfaction pre- and post-enrolled partners’ completion of an MBSR course. Results indicated that enrolled participants significantly improved on all facets of mindfulness and relationship satisfaction, while nonenrolled partners did not significantly increase on any facet of mindfulness or relationship satisfaction. Moreover, enrolled participants’ increases in Acting with Awareness were positively associated with increases in their own and their nonenrolled partners’ relationship satisfaction, whereas increases in enrolled participants’ Nonreactivity were positively associated with increases in their nonenrolled partners’ (but not their own) relationship satisfaction. These results suggest that increasing levels of mindfulness (particularly specific aspects of mindfulness) may have positive effects on couples’ relationship satisfaction and highlight mindfulness training as a promising tool for education and intervention efforts aimed at promoting relational health.
June 15th, 2016 at 1:36 pm
Int Rev Psychiatry. 2016 Jun 14:1-10.
Immediate effect of two yoga-based relaxation techniques on cognitive functions in patients suffering from relapsing remitting multiple sclerosis: A comparative study.
Cognitive impairment (CI) is an important feature of relapsing remitting multiple sclerosis (RRMS). Yogic relaxation techniques have been found useful in improving various cognitive domains in health and disease. Eighteen subjects (13 females) in the age range of 51.5 ± 12.72 years with the diagnosis of RRMS by a neurologist (McDonald Criteria 2010) since last 18.16 ± 12.59 years were recruited into the study from a neuro-rehabilitation centre in Germany. Assessments were done before and immediately after two randomly allocated 30-min sessions of yogic relaxation: Cyclic Meditation (CM) and SR (supine rest or shavasana). Assessments were done for attention, psychomotor performance, information processing speed, executive functions, and immediate and delayed recall using standard psychometric tools. RMANOVA was applied to analyse the data using SPSS version 10. Both CM and SR sessions improved scores on Digit Symbol Substitution Test (DSST) (p < 0.01) and Auditory Verbal Learning Test (AVLT) (p < 0.05). There was a significantly better performance in Trail Making Test (TMT)-A and forward digit span (FDS) after CM as compared to SR (p < 0.01). Yogic relaxation techniques may have an immediate enhancing effect on processing speed, psychomotor performance, and recall of RRMS patients. CM is better than SR in improving processing speed, short-term memory, and verbal working memory. Be well! JP
June 16th, 2016 at 10:35 pm
Lancet Neurol. 2016 Jul;15(8):801-10.
Safety and efficacy of cognitive training plus epigallocatechin-3-gallate in young adults with Down’s syndrome (TESDAD): a double-blind, randomised, placebo-controlled, phase 2 trial.
BACKGROUND: Early cognitive intervention is the only routine therapeutic approach used for amelioration of intellectual deficits in individuals with Down’s syndrome, but its effects are limited. We hypothesised that administration of a green tea extract containing epigallocatechin-3-gallate (EGCG) would improve the effects of non-pharmacological cognitive rehabilitation in young adults with Down’s syndrome.
METHODS: We enrolled adults (aged 16-34 years) with Down’s syndrome from outpatient settings in Catalonia, Spain, with any of the Down’s syndrome genetic variations (trisomy 21, partial trisomy, mosaic, or translocation) in a double-blind, placebo-controlled, phase 2, single centre trial (TESDAD). Participants were randomly assigned at the IMIM-Hospital del Mar Medical Research Institute to receive EGCG (9 mg/kg per day) or placebo and cognitive training for 12 months. We followed up participants for 6 months after treatment discontinuation. We randomly assigned participants using random-number tables and balanced allocation by sex and intellectual quotient. Participants, families, and researchers assessing the participants were masked to treatment allocation. The primary endpoint was cognitive improvement assessed by neuropsychologists with a battery of cognitive tests for episodic memory, executive function, and functional measurements. Analysis was on an intention-to-treat basis. This trial is registered with ClinicalTrials.gov, number NCT01699711.
FINDINGS: The study was done between June 5, 2012, and June 6, 2014. 84 of 87 participants with Down’s syndrome were included in the intention-to-treat analysis at 12 months (43 in the EGCG and cognitive training group and 41 in the placebo and cognitive training group). Differences between the groups were not significant on 13 of 15 tests in the TESDAD battery and eight of nine adaptive skills in the Adaptive Behavior Assessment System II (ABAS-II). At 12 months, participants treated with EGCG and cognitive training had significantly higher scores in visual recognition memory (Pattern Recognition Memory test immediate recall, adjusted mean difference: 6·23 percentage points [95% CI 0·31 to 12·14], p=0·039; d 0·4 [0·05 to 0·84]), inhibitory control (Cats and Dogs total score, adjusted mean difference: 0·48 [0·02 to 0·93], p=0·041; d 0·28 [0·19 to 0·74]; Cats and Dogs total response time, adjusted mean difference: -4·58 s [-8·54 to -0·62], p=0·024; d -0·27 [-0·72 to -0·20]), and adaptive behaviour (ABAS-II functional academics score, adjusted mean difference: 5·49 [2·13 to 8·86], p=0·002; d 0·39 [-0·06 to 0·84]). No differences were noted in adverse effects between the two treatment groups.
INTERPRETATION: EGCG and cognitive training for 12 months was significantly more effective than placebo and cognitive training at improving visual recognition memory, inhibitory control, and adaptive behaviour. Phase 3 trials with a larger population of individuals with Down’s syndrome will be needed to assess and confirm the long-term efficacy of EGCG and cognitive training.
June 26th, 2016 at 4:19 pm
Mediators Inflamm. 2016;2016:5912146.
Folic Acid Supplementation Mitigates Alzheimer’s Disease by Reducing Inflammation: A Randomized Controlled Trial.
Background/Aims. Low serum folate levels can alter inflammatory reactions. Both phenomena have been linked to Alzheimer’s disease (AD), but the effect of folic acid on AD itself is unclear. We quantified folate supplementation’s effect on inflammation and cognitive function in patients with AD over the course of 6 months.
Methods. Patients newly diagnosed with AD (age > 60 years; n = 121; mild to severe; international criteria) and being treated with donepezil were randomly assigned into two groups with (intervention group) or without (control group) supplemental treatment with folic acid (1.25 mg/d) for 6 months. The Mini-Mental State Examination (MMSE) was administered to all patients at baseline and follow-up, and blood samples were taken before and after treatment. We quantified serum folate, amyloid beta (Aβ), interleukin-6 (IL-6), tumor necrosis factor α (TNFα), plasma homocysteine (Hcy), S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), and the mRNA levels of presenilin (PS), IL-6, and TNFα in leukocytes. Data were analyzed using a repeated-measures mixed model.
Results. The mean MMSE was slightly increased in the intervention group compared to that in the control group (P < 0.05). Posttreatment, plasma SAM and SAM/SAH levels were significantly higher (P < 0.05), while Aβ 40, PS1-mRNA, and TNFα-mRNA levels were lower in the intervention group than in the control group (P < 0.05). The Aβ 42/Aβ 40 ratio was also higher in the intervention group (P < 0.05). Conclusions. Folic acid is beneficial in patients with AD. Inflammation may play an important role in the interaction between folic acid and AD. Be well! JP
July 17th, 2016 at 4:11 pm
Am J Clin Nutr. 2016 Jul 13.
Dietary flavonoid intake and risk of incident depression in midlife and older women.
BACKGROUND: The impact of dietary flavonoid intakes on risk of depression is unclear.
OBJECTIVE: We prospectively examined associations between estimated habitual intakes of dietary flavonoids and depression risk.
DESIGN: We followed 82,643 women without a previous history of depression at baseline from the Nurses’ Health Study [(NHS) aged 53-80 y] and the Nurses’ Health Study II [(NHSII) aged 36-55 y]. Intakes of total flavonoids and subclasses (flavonols, flavones, flavanones, anthocyanins, flavan-3-ols, polymeric flavonoids, and proanthocyanidins) were calculated from validated food-frequency questionnaires collected every 2-4 y. Depression was defined as physician- or clinician-diagnosed depression or antidepressant use and was self-reported in response to periodic questionnaires. Cox proportional hazards models were performed to examine associations.
RESULTS: A total of 10,752 incident depression cases occurred during a 10-y follow-up. Inverse associations between flavonol, flavone, and flavanone intakes and depression risk were observed. Pooled multivariable-adjusted HRs (95% CIs) were 0.93 (0.88, 0.99), 0.92 (0.86, 0.98), and 0.90 (0.85, 0.96) when comparing the highest (quintile 5) with the lowest (quintile 1) quintiles, respectively, with evidence of linear trends across quintiles (P-trend = 0.0004-0.08). In flavonoid-rich food-based analyses, the HR was 0.82 (95% CI: 0.74, 0.91) among participants who consumed ≥2 servings citrus fruit or juices/d compared with <1 serving/wk. In the NHS only, total flavonoids, polymers, and proanthocyanidin intakes showed significant (9-12%) lower depression risks. In analyses among late-life NHS participants (aged ≥65 y at baseline or during follow-up), for whom we were able to incorporate depressive symptoms into the outcome definition, higher intakes of all flavonoid subclasses except for flavan-3-ols were associated with significantly lower depression risk; flavones and proanthocyanidins showed the strongest associations (HR for both: 0.83; 95% CI: 0.77, 0.90).
CONCLUSIONS: Higher flavonoid intakes may be associated with lower depression risk, particularly among older women. Further studies are needed to confirm these associations.
July 18th, 2016 at 2:23 pm
Nutrients 2016, 8(7), 425
Acute Resveratrol Consumption Improves Neurovascular Coupling Capacity in Adults with Type 2 Diabetes Mellitus
Background: Poor cerebral perfusion may contribute to cognitive impairment in type 2 diabetes mellitus (T2DM). We conducted a randomized controlled trial to test the hypothesis that resveratrol can enhance cerebral vasodilator function and thereby alleviate the cognitive deficits in T2DM. We have already reported that acute resveratrol consumption improved cerebrovascular responsiveness (CVR) to hypercapnia. We now report the effects of resveratrol on neurovascular coupling capacity (CVR to cognitive stimuli), cognitive performance and correlations with plasma resveratrol concentrations.
Methods: Thirty-six T2DM adults aged 40–80 years were randomized to consume single doses of resveratrol (0, 75, 150 and 300 mg) at weekly intervals. Transcranial Doppler ultrasound was used to monitor changes in blood flow velocity (BFV) during a cognitive test battery. The battery consisted of dual-tasking (finger tapping with both Trail Making task and Serial Subtraction 3 task) and a computerized multi-tasking test that required attending to four tasks simultaneously. CVR to cognitive tasks was calculated as the per cent increase in BFV from pre-test basal to peak mean blood flow velocity and also as the area under the curve for BFV.
Results: Compared to placebo, 75 mg resveratrol significantly improved neurovascular coupling capacity, which correlated with plasma total resveratrol levels. Enhanced performance on the multi-tasking test battery was also evident following 75 mg and 300 mg of resveratrol.
Conclusion: a single 75 mg dose of resveratrol was able to improve neurovascular coupling and cognitive performance in T2DM. Evaluation of benefits of chronic resveratrol supplementation is now warranted.
August 27th, 2016 at 10:50 pm
Adv Exp Med Biol. 2016;923:215-22.
Effects of Antioxidant Supplements (BioPQQ™) on Cerebral Blood Flow and Oxygen Metabolism in the Prefrontal Cortex.
Pyrroloquinoline quinone (PQQ) is a quinone compound originally identified in methanol-utilizing bacteria and is a cofactor for redox enzymes. At the Meeting of the International Society on Oxygen Transport to Tissue (ISOTT) 2014, we reported that PQQ disodium salt (BioPQQ™) improved cognitive function in humans, as assessed by the Stroop test. However, the physiological mechanism of PQQ remains unclear. In the present study, we measured regional cerebral blood flow (rCBF) and oxygen metabolism in prefrontal cortex (PFC), before and after administration of PQQ, using time-resolved near-infrared spectroscopy (tNIRS). A total of 20 healthy subjects between 50 and 70 years of age were administered BioPQQ™ (20 mg) or placebo orally once daily for 12 weeks. Hemoglobin (Hb) concentration and absolute tissue oxygen saturation (SO2) in the bilateral PFC were evaluated under resting conditions using tNIRS. We found that baseline concentrations of hemoglobin and total hemoglobin in the right PFC significantly increased after administration of PQQ (p < 0.05). In addition, decreases in SO2 level in the PFC were more pronounced in the PQQ group than in the placebo group (p < 0.05). These results suggest that PQQ causes increased activity in the right PFC associated with increases in rCBF and oxygen metabolism, resulting in enhanced cognitive function. Be well! JP
September 1st, 2016 at 6:07 pm
Psychopharmacology (Berl). 2016 Aug 27.
Effect of a ketogenic meal on cognitive function in elderly adults: potential for cognitive enhancement.
RATIONALE: Glucose is the principal energy substrate for the brain, although ketone bodies are an effective alternative. Evidence suggests that elevation of plasma ketone body levels through oral intake of medium chain triglycerides (MCTs) may improve cognitive function.
We tried to examine the possible effects of a ketogenic meal serving on cognition in elderly non-demented subjects.
METHODS: Subjects were 19 non-demented elderly adults over 60 years old (13 females; mean age: 66.1 ± 2.9 years) who underwent neurocognitive tests 90 and 180 min after oral intake of a ketogenic meal (Ketonformula®) containing 20 g of MCTs and an isocaloric placebo meal without MCTs on separate days.
RESULTS: Elevation of plasma ketone concentration after intake of a single ketogenic meal containing 20 g of MCTs was confirmed (all p < 0.001). As for cognition, improvements were observed in the digit span test, Trail-Making Test B, and the global score (Z = -2.4, p = 0.017) following the ketogenic meal and the change in the executive functioning score was positively correlated with that of the plasma β-hydroxybutyrate level. The cognition-enhancing effect was observed predominantly for individuals who had a relatively low global score at baseline (Z = -2.8, p = 0.005), compared to individuals with a high global score (Z = -0.7, p = 0.51). CONCLUSIONS: Plasma levels of ketone bodies were successfully increased after intake of the ketogenic meal. The ketogenic meal was suggested to have positive effects on working memory, visual attention, and task switching in non-demented elderly. Be well! JP
October 8th, 2016 at 10:15 pm
J Alzheimers Dis. 2016 Oct 1.
Effects of DHA Supplementation on Hippocampal Volume and Cognitive Function in Older Adults with Mild Cognitive Impairment: A 12-Month Randomized, Double-Blind, Placebo-Controlled Trial.
Docosahexaenoic acid (DHA) is important for brain function, and higher DHA intake is inversely correlated with relative risk of Alzheimer’s disease. The potential benefits of DHA supplementation in people with mild cognitive impairment (MCI) have not been fully examined. Our study aimed to determine the effect of DHA supplementation on cognitive function and hippocampal atrophy in elderly subjects with MCI. This was a randomized, double-blind, placebo-controlled trial in Tianjin, China. 240 individuals with MCI aged 65 years and over were recruited and equalized randomly allocated to the DHA or the placebo group. Participants received 12-month DHA supplementation (2 g/day) or corn oil as placebo. Both global and specific subdomains of cognitive function and hippocampal volume were measured at baseline, 6 months, and 12 months. Both changes were analyzed by repeated-measure analysis of variance (ANOVA). This trial has been registered: ChiCTR-IOR-15006058. A total of 219 participants (DHA: 110, Placebo: 109) completed the trial. The change in mean serum DHA levels was greater in the intervention group (+3.85%) compared to the control group (+1.06%). Repeated-measures analyses of covariance showed that, over 12 months, there was a significant difference in the Full-Scale Intelligence Quotient (ηp2 = 0.084; p = 0.039), Information (ηp2 = 0.439; p = 0.000), and Digit Span (ηp2 = 0.375; p = 0.000) between DHA-treated versus the placebo group. In addition, there were significant differences in volumes of left hippocampus (ηp2 = 0.121, p = 0.016), right hippocampus (ηp2 = 0.757, p = 0.008), total hippocampus (ηp2 = 0.124, p = 0.023), and global cerebrum (ηp2 = 0.145, p = 0.032) between the two groups. These findings suggest that DHA supplementation (2 g/day) for 12 months in MCI subjects can significantly improve cognitive function and slow the progression of hippocampal atrophy. Larger, longer-term confirmatory studies are warranted.
October 8th, 2016 at 11:23 pm
J Alzheimers Dis. 2016 Oct 4.
BDNF Responses in Healthy Older Persons to 35 Minutes of Physical Exercise, Cognitive Training, and Mindfulness: Associations with Working Memory Function.
Brain-derived neurotrophic factor (BDNF) has a central role in brain plasticity by mediating changes in cortical thickness and synaptic density in response to physical activity and environmental enrichment. Previous studies suggest that physical exercise can augment BDNF levels, both in serum and the brain, but no other study has examined how different types of activities compare with physical exercise in their ability to affect BDNF levels. By using a balanced cross over experimental design, we exposed nineteen healthy older adults to 35-minute sessions of physical exercise, cognitive training, and mindfulness practice, and compared the resulting changes in mature BDNF levels between the three activities. We show that a single bout of physical exercise has significantly larger impact on serum BDNF levels than either cognitive training or mindfulness practice in the same persons. This is the first study on immediate BDNF effects of physical activity in older healthy humans and also the first study to demonstrate an association between serum BDNF responsivity to acute physical exercise and working memory function. We conclude that the BDNF increase we found after physical exercise more probably has a peripheral than a central origin, but that the association between post-intervention BDNF levels and cognitive function could have implications for BDNF responsivity in serum as a potential marker of cognitive health.
November 7th, 2016 at 2:16 pm
J Altern Complement Med. 2016 Nov 3.
Hatha Yoga Practice Improves Attention and Processing Speed in Older Adults: Results from an 8-Week Randomized Control Trial.
BACKGROUND: Age-related cognitive decline is well documented across various aspects of cognitive function, including attention and processing speed, and lifestyle behaviors such as physical activity play an important role in preventing cognitive decline and maintaining or even improving cognitive function.
PURPOSE: The purpose of this study was to evaluate the effects of an 8-week Hatha yoga intervention on attention and processing speed among older adults.
METHODS: Participants (n = 118; mean age, 62 ± 5.59) were randomly assigned to an 8-week Hatha yoga group or a stretching control group and completed cognitive assessments-Attention Network Task, Trail Making Test parts A and B, and Pattern Comparison Test-at baseline and after the 8-week intervention.
RESULTS: Analyses of covariance revealed significantly faster reaction times for the yoga group on the Attention Network Task’s neutral, congruent, and incongruent conditions (p ≤ 0.04). The yoga intervention also improved participants’ visuospatial and perceptual processing on the Trail Making Test part B (p = 0.002) and pattern comparison (p < 0.001) tests. CONCLUSIONS: These results suggest that yoga practice that includes postures, breathing, and meditative exercises lead to improved attentional and information processing abilities. Although the underlying mechanisms remain largely speculative, more systematic trials are needed to explore the extent of cognitive benefits and their neurobiological mechanisms. Be well! JP
November 11th, 2016 at 12:50 am
PLoS One. 2016 Nov 8;11(11):e0165861.
Meta-Analysis of the Association between Tea Intake and the Risk of Cognitive Disorders.
BACKGROUND: Alzheimer’s disease is a common neurodegenerative disorder in elderly. This study was aimed to systematically evaluate the association between tea intake and the risk of cognitive disorders by meta-analysis.
METHODS AND FINDINGS: PubMed, Embase and Wanfang databases were systematically searched and a total of 26 observational studies were included in this study. Odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) were calculated and pooled by using fixed or random effects models according to the degree of heterogeneity.
RESULTS: The overall pooled analysis indicated that tea intake could significantly reduce the risk of cognitive disorders (OR = 0.65, 95%CI = 0.58-0.73). Subgroup analyses were conducted based on study design, population, frequency of tea drinking and type of cognitive disorders. The results showed that tea drinking was significantly associated with the reduced incidence of cognitive disorders in all of subgroups based on study design and frequency of tea drinking. In particular, tea drinking was inversely associated with the risk of cognitive impairment (CoI), mild cognitive impairment (MCI), cognitive decline and ungrouped cognitive disorders. Moreover, for population subgroups, the significant association was only found in Chinese people.
CONCLUSION: Our study suggests that daily tea drinking is associated with decreased risk of CoI, MCI and cognitive decline in the elderly. However, the association between tea intake and Alzheimer’s disease remains elusive.
November 20th, 2016 at 11:22 pm
Nutrients 2016, 8(11), 736
Randomized Prospective Double-Blind Studies to Evaluate the Cognitive Effects of Inositol-Stabilized Arginine Silicate in Healthy Physically Active Adults
Inositol-stabilized arginine silicate (ASI; Nitrosigine®) has been validated to increase levels of arginine, silicon and nitric oxide production. To evaluate potential enhancement of mental focus and clarity, ASI (1500 mg/day) was tested in two double-blind placebo-controlled crossover (DBPC-X) studies using the Trail Making Test (TMT, Parts A and B). In the two studies, healthy males took ASI for 14 and 3 days, respectively. In the first study, after 14 days of dosing, TMT B time decreased significantly from baseline (28% improvement, p = 0.045). In the second study evaluating shorter-term effects, TMT B time decreased significantly compared to placebo (33% improvement, p = 0.024) in a 10-min period. After 3 days of dosing, TMT B time significantly decreased from baseline scores (35% improvement, p < 0.001). These findings show that ASI significantly improved the ability to perform complex cognitive tests requiring mental flexibility, processing speed and executive functioning. Be well! JP
November 23rd, 2016 at 1:02 am
Evid Based Complement Alternat Med. 2016;2016:4103423.
Efficacy of Standardized Extract of Bacopa monnieri (Bacognize®) on Cognitive Functions of Medical Students: A Six-Week, Randomized Placebo-Controlled Trial.
Rationale. Bacopa monnieri, popularly known as Brahmi, has been traditionally used in Ayurveda since ages for its memory enhancing properties. However, data on placebo-controlled trial of Bacopa monnieri on intellectual sample is scarce. Hence this study was planned to evaluate the effect of Bacopa monnieri on memory of medical students for six weeks. Objective. To evaluate the efficacy of Bacopa monnieri on memory of medical students with six weeks’ administration. Method and Material. This was a randomized double blind placebo-controlled noncrossover, parallel trial. Sixty medical students of either gender from second year of medical school, third term, regular batch, were enrolled from Government Medical College, Nagpur, India. Baseline biochemical and memory tests were done. The participants were randomly divided in two groups to receive either 150 mg of standardized extract of Bacopa monnieri (Bacognize) or matching placebo twice daily for six weeks. All baseline investigations were repeated at the end of the trial. Students were followed up for 15 days after the intervention. Results. Statistically significant improvement was seen in the tests relating to the cognitive functions with use of Bacopa monnieri. Blood biochemistry also showed a significant increase in serum calcium levels (still within normal range).
December 5th, 2016 at 8:35 pm
J Parkinsons Dis. 2016 Nov 26.
The Effects of Meditation on Grey Matter Atrophy and Neurodegeneration: A Systematic Review.
The present systematic review is based on the premise that a variety of neurodegenerative diseases are accompanied by grey matter atrophy in the brain and meditation may impact this. Given that age is a major risk factor for many of these progressive and neurodegenerative diseases and that the percentage of the population over the age of 65 is quickly increasing, there is an obvious need for prompt treatment and prevention advances in research. As there is currently no cure for Alzheimer’s disease and other neurodegenerative diseases, many are seeking non-pharmacological treatment options in attempts to offset the disease-related cognitive and functional declines. On the basis of a growing body of research suggesting that meditation is effective in increasing grey matter volume in healthy participants, this paper systematically reviewed the literature regarding the effects of meditation on restoring grey matter volume in healthy individuals and those affected by neurodegeneration. This review searched PubMed, CINAHL, and APA PsycNET to identify original studies that included MRI imaging to measure grey matter volume in meditators and post-mindfulness-based intervention participants compared to controls. Thirteen studies were considered eligible for review and involved a wide variety of meditation techniques and included participants with and without cognitive impairment. All studies reported significant increases in grey matter volume in the meditators/intervention group, albeit in assorted regions of the brain. Limited research exists on the mechanisms through which meditation affects disease-related neurodegeneration, but preliminary evidence suggests that it may offset grey matter atrophy.
December 12th, 2016 at 3:23 pm
J Nutr Health Aging. 2016;20(10):1002-1009.
Tea Consumption Reduces the Incidence of Neurocognitive Disorders: Findings from the Singapore Longitudinal Aging Study.
OBJECTIVES: To examine the relationships between tea consumption habits and incident neurocognitive disorders (NCD) and explore potential effect modification by gender and the apolipoprotein E (APOE) genotype.
DESIGN: Population-based longitudinal study.
SETTING: The Singapore Longitudinal Aging Study (SLAS).
PARTICIPANTS: 957 community-living Chinese elderly who were cognitively intact at baseline.
MEASUREMENTS: We collected tea consumption information at baseline from 2003 to 2005 and ascertained incident cases of neurocognitive disorders (NCD) from 2006 to 2010. Odds ratio (OR) of association were calculated in logistic regression models that adjusted for potential confounders.
RESULTS: A total of 72 incident NCD cases were identified from the cohort. Tea intake was associated with lower risk of incident NCD, independent of other risk factors. Reduced NCD risk was observed for both green tea (OR=0.43) and black/oolong tea (OR=0.53) and appeared to be influenced by the changing of tea consumption habit at follow-up. Using consistent non-tea consumers as the reference, only consistent tea consumers had reduced risk of NCD (OR=0.39). Stratified analyses indicated that tea consumption was associated with reduced risk of NCD among females (OR=0.32) and APOE ε4 carriers (OR=0.14) but not males and non APOE ε4 carriers.
CONCLUSION: Regular tea consumption was associated with lower risk of neurocognitive disorders among Chinese elderly. Gender and genetic factors could possibly modulate this association.
January 8th, 2017 at 10:44 pm
Sci Rep. 2017 Jan 3;7:39471.
Randomized trial on the effects of a combined physical/cognitive training in aged MCI subjects: the Train the Brain study.
Age-related cognitive impairment and dementia are an increasing societal burden. Epidemiological studies indicate that lifestyle factors, e.g. physical, cognitive and social activities, correlate with reduced dementia risk; moreover, positive effects on cognition of physical/cognitive training have been found in cognitively unimpaired elders. Less is known about effectiveness and action mechanisms of physical/cognitive training in elders already suffering from Mild Cognitive Impairment (MCI), a population at high risk for dementia. We assessed in 113 MCI subjects aged 65-89 years, the efficacy of combined physical-cognitive training on cognitive decline, Gray Matter (GM) volume loss and Cerebral Blood Flow (CBF) in hippocampus and parahippocampal areas, and on brain-blood-oxygenation-level-dependent (BOLD) activity elicited by a cognitive task, measured by ADAS-Cog scale, Magnetic Resonance Imaging (MRI), Arterial Spin Labeling (ASL) and fMRI, respectively, before and after 7 months of training vs. usual life. Cognitive status significantly decreased in MCI-no training and significantly increased in MCI-training subjects; training increased parahippocampal CBF, but no effect on GM volume loss was evident; BOLD activity increase, indicative of neural efficiency decline, was found only in MCI-no training subjects. These results show that a non pharmacological, multicomponent intervention improves cognitive status and indicators of brain health in MCI subjects.
January 11th, 2017 at 12:38 am
Nutr Healthy Aging. 2016 Oct 27;4(1):81-93.
High-flavonoid intake induces cognitive improvements linked to changes in serum brain-derived neurotrophic factor: Two randomised, controlled trials.
BACKGROUND: Recent clinical studies have indicated the beneficial impact of dietary flavonoid intake on human cognitive performance. Although the mechanisms that mediate such improvements are currently unclear, animal and human trial data suggest that changes in neurotrophin expression, and related signalling apparatus, may be involved. OBJECTIVE: To investigate the link between changes in serum brain-derived neurotrophic factor (BDNF) and changes in human cognitive performance following flavonoid intake. METHODS: The relationship between serum levels of BDNF and age, gender, BMI, waist circumference, blood pressure and cognition at baseline, and following flavonoid intake, was investigated in two distinct randomised, controlled clinical trials. Trial 1 was conducted in men and women (aged 26-70 y; consuming an average of 3 portions of fruit and vegetables per day) and delivered high-flavonoid (>15 mg/100 g) or low-flavonoid (<5 mg/100 g) fruit and vegetables and increased intake by 2 portions every 6 weeks. The control arm was habitual diet over the same time frame. Trial 2 was conducted in an older males and female cohort (aged 62-75 y) intervening with a high-flavanol cocoa drink (494 mg total flavanols) and a low-flavanol cocoa drink (23 mg total flavanols) for 12 weeks. RESULTS: Serum BDNF levels increased linearly to the age of 65, after which BDNF levels were found to decrease markedly. All other physiological and anthropometric measurements proved to not be significantly associated with serum BDNF levels (p > 0.05), although higher levels in males compared to females almost achieved significance (p = 0.056). At baseline, higher serum BDNF levels were associated with significantly better global cognition scores, relative to individuals with lower serum levels. In addition, following intervention for 18 weeks, high-flavonoid, but not low-flavonoid, fruit and vegetable intake induced significant improvements in cognitive performance and increases in serum BDNF levels (p = <0.001). Flavanol intervention for 12 weeks also resulted in significant increases in serum BDNF (p = <0.001), and such increases were correlated with improvements in global cognitive performance. CONCLUSION: Increases in global cognition induced by high flavonoid fruit and vegetables, and cocoa flavanols were paralleled by concurrent changes in serum BDNF levels, suggesting a role for BDNF in flavonoid-induced cognitive improvements. Furthermore, we provide further data suggesting that serum BDNF levels may represent a biomarker of cognitive function.
January 21st, 2017 at 5:32 pm
J Alzheimers Dis. 2017 Jan 18.
Meditation and Music Improve Memory and Cognitive Function in Adults with Subjective Cognitive Decline: A Pilot Randomized Controlled Trial.
BACKGROUND: While effective therapies for preventing or slowing cognitive decline in at-risk populations remain elusive, evidence suggests mind-body interventions may hold promise.
OBJECTIVES: In this study, we assessed the effects of Kirtan Kriya meditation (KK) and music listening (ML) on cognitive outcomes in adults experiencing subjective cognitive decline (SCD), a strong predictor of Alzheimer’s disease.
METHODS: Sixty participants with SCD were randomized to a KK or ML program and asked to practice 12 minutes/day for 3 months, then at their discretion for the ensuing 3 months. At baseline, 3 months, and 6 months we measured memory and cognitive functioning [Memory Functioning Questionnaire (MFQ), Trail-making Test (TMT-A/B), and Digit-Symbol Substitution Test (DSST)].
RESULTS: The 6-month study was completed by 53 participants (88%). Participants performed an average of 93% (91% KK, 94% ML) of sessions in the first 3 months, and 71% (68% KK, 74% ML) during the 3-month, practice-optional, follow-up period. Both groups showed marked and significant improvements at 3 months in memory and cognitive performance (MFQ, DSST, TMT-A/B; p’s ≤0.04). At 6 months, overall gains were maintained or improved (p’s ≤ 0.006), with effect sizes ranging from medium (DSST, ML group) to large (DSST, KK group; TMT-A/B, MFQ). Changes were unrelated to treatment expectancies and did not differ by age, gender, baseline cognition scores, or other factors.
CONCLUSIONS: Findings of this preliminary randomized controlled trial suggest practice of meditation or ML can significantly enhance both subjective memory function and objective cognitive performance in adults with SCD, and may offer promise for improving outcomes in this population.
February 2nd, 2017 at 8:06 pm
Brain Topogr. 2017 Jan 27.
Higher Fasting Plasma Glucose is Associated with Increased Cortical Thinning Over 12 Years: The PATH Through Life Study.
Recent evidence suggests that type 2 diabetes (T2D) is associated with accelerated brain ageing, consistent with the observation of increased risk of cognitive impairment and dementia in affected individuals. Even non-diabetic individuals with impaired fasting plasma glucose (IFG) levels have shown increased cerebral atrophy, compared to individuals with normal glucose levels. We tested whether longitudinal rates of age-related cortical thinning were associated with fasting plasma glucose levels in a large sample (n = 322) of early-old age individuals (60-66 years) who were scanned with magnetic resonance imaging (1.5 T) on up to four occasions over 12 years. Higher plasma glucose levels (measured on up to three occasions) were associated with increased cortical thinning in individuals with T2D as well as those with IFG, with a similar trend for individuals with normal fasting glucose (NFG) levels. Across groups, a 1 mmol/l increase in plasma glucose (above 5 mmol/l in NFG and IFG and above 6.1 mmol/l in T2D) resulted in a 10-13% increase in annual cortical thinning. Increased cortical thinning was detected in insular cortex, as well as posterior cingulate, parahippocampus and medial orbitofrontal cortex. Our results provide support for the idea that raised plasma glucose levels, even in the normal range, are associated with accelerated age-related cortical atrophy.
February 6th, 2017 at 11:22 pm
J Alzheimers Dis. 2017 Feb 1.
A 3-Month Aerobic Training Program Improves Brain Energy Metabolism in Mild Alzheimer’s Disease: Preliminary Results from a Neuroimaging Study.
BACKGROUND: Aerobic training has some benefits for delaying the onset or progression of Alzheimer’s disease (AD). Little is known about the implication of the brain’s two main fuels, glucose and ketones (acetoacetate), associated with thesebenefits.
OBJECTIVE: To determine whether aerobic exercise training modifies brain energy metabolism in mild AD.
METHODS: In this uncontrolled study, ten patients with mild AD participated in a 3-month, individualized, moderate-intensity aerobic training on a treadmill (Walking). Quantitative measurement of brain uptake of glucose (CMRglu) and acetoacetate (CMRacac) using neuroimaging and cognitive testing were done before and after the Walking program.
RESULTS: Four men and six women with an average global cognitive score (MMSE) of 26/30 and an average age of 73 y completed the Walking program. Average total distance and treadmill speed were 8 km/week and 4 km/h, respectively. Compared to the Baseline, after Walking, CMRacac was three-fold higher (0.6±0.4 versus 0.2±0.1 μmol/100 g/min; p = 0.01). Plasma acetoacetate concentration and the blood-to-brain acetoacetate influx rate constant were also increased by 2-3-fold (all p≤0.03). CMRglu was unchanged after Walking (28.0±0.1 μmol/100 g/min; p = 0.96). There was a tendency toward improvement in the Stroop-color naming test (-10% completion time, p = 0.06). Performance on the Trail Making A&B tests was also directly related to plasma acetoacetate and CMRacac (all p≤0.01).
CONCLUSION: In mild AD, aerobic training improved brain energy metabolism by increasing ketone uptake and utilization while maintaining brain glucose uptake, and could potentially be associated with some cognitive improvement.
March 2nd, 2017 at 2:10 pm
Appl Physiol Nutr Metab. 2017 Mar 1.
Enhanced task related brain activation and resting perfusion in healthy older adults after chronic blueberry supplementation.
Blueberries are rich in flavonoids, which possess antioxidant and anti-inflammatory properties. High flavonoid intakes attenuate age-related cognitive decline, but data from human intervention studies are sparse. We investigated whether 12 weeks of blueberry concentrate supplementation improved brain perfusion, task-related activation and cognitive function in healthy older adults. Participants were randomised to consume either 30 ml blueberry concentrate providing 387 mg anthocyanidins (5 female, 7 male; age 67.5±3.0 y; BMI, 25.9±3.3 kg.m-2) or isoenergetic placebo (8 female, 6 male; age 69.0 ±3.3 y; BMI, 27.1±.4.0 kg.m-2). Pre- and post-supplementation, participants undertook a battery of cognitive function tests and a numerical Stroop test within a 1.5T MRI scanner while functional magnetic resonance images (fMRI) were continuously acquired. Quantitative resting brain perfusion was determined using an arterial spin labelling (ASL) technique, and blood biomarkers of inflammation and oxidative stress were measured. Significant increases in brain activity were observed in response to blueberry supplementation relative to the placebo group within Brodmann areas 4/6/10/21/40/44/45, precuneus, anterior cingulate, and insula/thalamus (p<0.001), as well as significant improvements in grey matter perfusion in the parietal (5.0±1.8 vs -2.9±2.4 %, p=0.013) and occipital (8.0±2.6 vs -0.7±3.2 %, p=0.031) lobes. There was also evidence suggesting improvement in working memory (two back test) after blueberry versus placebo supplementation (p=0.05). Supplementation with an anthocyanin rich blueberry concentrate improved brain perfusion and activation in brain areas associated with cognitive function in healthy older adults.
March 4th, 2017 at 3:51 pm
J Nutr Health Aging. 2017;21(3):276-283.
Association between Dietary Sodium Intake and Cognitive Function in Older Adults.
OBJECTIVE: To examine the association of dietary sodium intake with cognitive function in community-dwelling older adults.
DESIGN: Cross-sectional study.
SETTING: Southern California community.
PARTICIPANTS: White men (n=373) and women (n=552), aged 50-96 years from the Rancho Bernardo Study, a longitudinal study of cardiovascular disease risk factors and healthy aging.
MEASUREMENTS: During the 1992-1996 research clinic visit, a food frequency questionnaire was used to determine daily sodium intake; cognitive function was assessed with Trails Making Test, part B (Trails B), Mini-Mental State Exam (MMSE), and Verbal Fluency Test (VFT); and medical, clinical and demographic information was obtained. Linear regression was used to assess the association between calorie-adjusted sodium intake and cognitive test scores with adjustment for demographic, behavioral and health measures. Logistic regression examined the odds of having cognitive impairment by sodium intake.
RESULTS: Lower sodium intake was associated with poorer performance on Trails B (p=0.008) and MMSE (p=0.003) after controlling for age, sex, and education. Associations did not differ by sex, but there was a significant interaction by age for the Trails B: older (≥80 years), but not younger, adults showed worse performance with lower sodium intake (p=0.03). Associations remained significant after additional adjustment for smoking, alcohol intake, exercise, body weight, cardiovascular risk factors, kidney function, diuretic medication use, and diet quality. Lower daily sodium intake was associated with increased odds of cognitive impairment on the MMSE (score < 26; OR per SD decrease = 1.12, 95% CI 1.08, 1.16). Concluson: Lower sodium intake was associated with worse cognitive function in older community-dwelling adults. For the maintenance of cognitive health, older adults may be advised to avoid very low sodium diets. Be well! JP
March 12th, 2017 at 2:07 pm
Alzheimers Dement. 2017 Mar 5.
Sugary beverage intake and preclinical Alzheimer’s disease in the community.
INTRODUCTION: Excess sugar consumption has been linked with Alzheimer’s disease (AD) pathology in animal models.
METHODS: We examined the cross-sectional association of sugary beverage consumption with neuropsychological (N = 4276) and magnetic resonance imaging (N = 3846) markers of preclinical Alzheimer’s disease and vascular brain injury (VBI) in the community-based Framingham Heart Study. Intake of sugary beverages was estimated using a food frequency questionnaire.
RESULTS: Relative to consuming less than one sugary beverage per day, higher intake of sugary beverages was associated with lower total brain volume (1-2/day, β ± standard error [SE] = -0.55 ± 0.14 mean percent difference, P = .0002; >2/day, β ± SE = -0.68 ± 0.18, P < .0001), and poorer performance on tests of episodic memory (all P < .01). Daily fruit juice intake was associated with lower total brain volume, hippocampal volume, and poorer episodic memory (all P < .05). Sugary beverage intake was not associated with VBI in a consistent manner across outcomes.
DISCUSSION: Higher intake of sugary beverages was associated cross-sectionally with markers of preclinical AD.
March 23rd, 2017 at 2:36 pm
Gerontologist. 2017 Mar 15.
The Influence of Exercise on Cognitive Function in Older Hispanic/Latino Adults: Results From the “¡Caminemos!” Study.
Purpose of the Study: We examined the prospective effect of an evidence-based exercise intervention (¡Caminemos!) on cognitive function among older Hispanic/Latino adults and the potential synergistic effects (if any) of an attribution-retraining intervention given to a random sample to counter negative ascriptions of the aging process.
Design and Methods: We analyzed baseline and follow-up (1- and 2-year) data collected from Hispanics/Latinos ≥60 years (N = 571) who participated in ¡Caminemos! across 27 senior centers. All participants were randomly assigned to either (a) the treatment group-a 1-hr attribution-retraining session plus a 1-hr exercise class or (b) the control group-health education plus a 1-hr exercise class. Mixed-effects linear regression was used to determine the effects of the exercise class and the attribution-retraining component on longitudinal changes in cognitive functioning, as measured by the Modified Mini-Mental State (3MS) examination.
Results: In analyses adjusted for age, sex, education, income, and medical comorbidities, participants in both trial arms displayed higher cognitive functioning scores at the 1-year (β = 1.76, p = .001) and 2-year (β = 1.37, p = .013) follow-ups when compared with original baseline scores. However, we found no significant difference in cognitive function between the treatment versus control conditions (β = 0.41, p = .582), nor were any differences found across groups over time.
Implications: The exercise intervention improved cognitive function in older Hispanics/Latinos, regardless of whether it was supplemented with the age-related attribution retraining. These findings suggest that limited access to exercise programs may be a greater obstacle in forestalling cognitive decline in older Hispanics/Latinos than the negative beliefs they might hold of the aging process.
March 25th, 2017 at 2:46 pm
J Affect Disord. 2017 Mar 18;215:152-155.
Exercise increases serum brain-derived neurotrophic factor in patients with major depressive disorder.
BACKGROUND: Brain derived neurotrophic factor (BDNF) has been implicated in the pathogenesis of major depressive disorder (MDD). Existing data on exercise treatment in people with MDD are inconsistent concerning the effect of exercise on BDNF pointing either to increased or unaltered BDNF concentrations. However, studies in non-depressed persons demonstrated a significant effect on resting peripheral BDNF concentrations in aerobic training interventions. Given the lack of clarity mentioned above, the current study aimed at examining the effect of adjunctive exercise on serum BDNF levels in guideline based treated patients with MDD.
METHODS: 42 depressed inpatients were included, and randomized either to a 6 week structured and supervised exercise intervention plus treatment as usual (EXERCISE, n=22), or to treatment as usual (TAU, n=20). BDNF serum concentrations were assessed before and after the intervention in both study groups with established immunoassays.
RESULTS: Serum BDNF slightly decreased in the TAU group, whilst there was an increase in BDNF levels in the exercise group. There was a significant time x group effect concerning sBDNF (p=0.030) with repeated ANOVA measures with age and BMI as covariates, suggesting an increase in BDNF concentrations in the EXERCISE group compared to TAU.
LIMITATIONS: Though there was no statistic difference in the antidepressant medication between EXERCISE and TAU potential interactions between exercise and medication on the effects of exercise in BDNF cannot be excluded. Gender was not considered as a covariate in ANOVA due to the small number of objects.
CONCLUSIONS: Exercise training given as adjunct to standard guideline based treatment appears to have additional effects on BDNF serum concentrations in people with MDD. Our results add further evidence to the beneficial effects of exercise in the treatment of MDD.
April 3rd, 2017 at 2:34 pm
J Gerontol A Biol Sci Med Sci. 2016 Nov 9.
Beet Root Juice: An Ergogenic Aid for Exercise and the Aging Brain.
Background: Exercise has positive neuroplastic effects on the aging brain. It has also been shown that ingestion of beet root juice (BRJ) increases blood flow to the brain and enhances exercise performance. Here, we examined whether there are synergistic effects of BRJ and exercise on neuroplasticity in the aging brain.
Methods: Peak metabolic equivalent (MET) capacity and resting-state magnetic resonance imaging functional brain network organization are reported on 26 older (mean age = 65.4 years) participants randomly assigned to 6 weeks of exercise + BRJ or exercise + placebo.
Results: Somatomotor community structure consistency was significantly enhanced in the exercise + BRJ group following the intervention (MBRJ = -2.27, SE = 0.145, MPlacebo = -2.89, SE = 0.156, p = .007). Differences in second-order connections between the somatomotor cortex and insular cortex were also significant; the exercise + BRJ group (M = 3.28, SE = 0.167) had a significantly lower number of connections than exercise + placebo (M = 3.91, SE = 0.18, p = .017) following the intervention. Evaluation of peak MET capacity revealed a trend for the exercise + BRJ group to have higher MET capacity following the intervention.
Conclusions: Older adults who exercised and consumed BRJ demonstrated greater consistency within the motor community and fewer secondary connections with the insular cortex compared with those who exercised without BRJ. The exercise + BRJ group had brain networks that more closely resembled those of younger adults, showing the potential enhanced neuroplasticity conferred by combining exercise and BRJ consumption.
April 23rd, 2017 at 12:45 pm
Eur J Nutr. 2017 Apr 20.
Cognitive and mood improvements following acute supplementation with purple grape juice in healthy young adults.
PURPOSE: Berry-derived phenolic compounds found in grapes have been associated with a number of health benefits, including the augmentation of human brain function and cognition. Previous intervention studies of Concord grape juice have demonstrated improvement to memory and driving ability following 3- to 4-month supplementation in middle-aged and older adults. However, no studies to date have demonstrated acute cognitive benefits of grape juice, and investigation of these effects in young adults is lacking.
METHODS: This randomised, placebo-controlled, double-blind, counterbalanced-crossover study, assessed the effects of 230 ml purple grape juice or sugar-matched control in 20 healthy young adults. Computerised measures of episodic memory, working memory, attention and mood were completed at baseline and following a 20-min absorption period.
RESULTS: Purple grape juice significantly improved reaction time on a composite attention measure (p = 0.047) and increased calm ratings (p = 0.046) when compared to placebo. Order effects also indicated an enduring positive effect on pre-dose memory reaction time (p = 0.018) and post-dose calm ratings (p = 0.019) when purple grape was consumed first.
CONCLUSIONS: These findings in a small sample of healthy young adults suggest that purple grape juice can acutely enhance aspects of cognition and mood. No significant effects of juice were observed on memory measures, suggesting that these may be less susceptible to manipulation following acute supplementation in healthy young adults. Potential mechanisms underlying these effects include modulation of cerebral blood flow, glucoregulation and inhibition of monoamine oxidase activity, all of which require further exploration.
May 31st, 2017 at 8:33 pm
J Nutr Sci Vitaminol (Tokyo). 2017;63(2):133-140.
Medium-Chain Triglycerides in Combination with Leucine and Vitamin D Benefit Cognition in Frail Elderly Adults: A Randomized Controlled Trial.
The combined supplementation of medium-chain triglycerides (MCTs), L-leucine-rich amino acids, and cholecalciferol (vitamin D3) increase muscle strength and function in frail elderly individuals. However, their effects on cognition are unknown. We enrolled 38 elderly nursing home residents (mean age±SD, 86.6±4.8 y) in a 3-mo randomized, controlled, parallel group trial. The participants were randomly allocated to 3 groups: the first group received a L-leucine (1.2 g)- and cholecalciferol (20 μg)-enriched supplement with 6 g of MCT (LD+MCT); the second group received the same supplement with 6 g of long-chain triglycerides (LD+LCT); and the third group did not receive any supplements (control). Cognition was assessed at baseline and after the 3-mo intervention. The difference in changes among the groups was assessed with ANCOVA, adjusting for age and the baseline value as covariates. After 3 mo, the Mini-Mental State Examination (MMSE) score in the LD+MCT group increased by 10.6% (from 16.6 to 18.4 points, p<0.05). After 3 mo, the Nishimura geriatric rating scale for mental status (NM scale) score in the LD+MCT group increased by 30.6% (from 24.6 to 32.2 points, p<0.001), whereas that in the LD+LCT and control groups decreased by 11.2% (from 31.2 to 27.7 points, p<0.05) and 26.1% (from 27.2 to 20.1 points, p<0.001), respectively. The combined supplementation of MCTs (6 g), L-leucine-rich amino acids, and cholecalciferol may improve cognitive function in frail elderly individuals.
June 11th, 2017 at 3:51 pm
J Clin Psychopharmacol. 2017 Jun 6.
Bergamot Polyphenolic Fraction Supplementation Improves Cognitive Functioning in Schizophrenia: Data From an 8-Week, Open-Label Pilot Study.
BACKGROUND: Novel treatment strategies for cognitive dysfunctions may prevent long-term disability in patients with schizophrenia, and polyphenolic compounds might be a promising strategy. Bergamot (Citrus bergamia), a citrus fruit characterized by a high amount of flavonoids and flavonoid glycosides, may represent a potential nutraceutical approach to cognitive dysfunction. The present study was aimed to explore the efficacy of bergamot polyphenolic fraction (BPF) supplementation on cognitive/executive functioning in a sample of patients with schizophrenia receiving second-generation antipsychotics.
METHODS: Twenty outpatients treated with second-generation antipsychotics assumed BPF at an oral daily dose of 1000 mg/d for 8 weeks. Brief Psychiatric Rating Scale, Wisconsin Card Sorting Test (WCST), Verbal Fluency Task-Controlled Oral Word Association Test, and Stroop Color-Word Test were administered.
RESULTS: At end point, (week 8) BPF supplementation significantly improved WCST “perseverative errors” (P = 0.004) and semantic fluency test (P = 0.004). Moreover, a trend for other cognitive variable (WCST “categories,” phonemic fluency, and Stroop Color-Word Test) improvement was observed.
CONCLUSIONS: The findings provide evidence that BPF administration may be proposed as a potential supplementation strategy to improve cognitive outcome in schizophrenia. Further clinical trials with adequately powered and well-designed methodology are needed to better explore the BPF effectiveness on cognitive impairments in patients with schizophrenia.
July 4th, 2017 at 1:59 pm
Nutrients 2017, 9(7), 685
Brain Functional Connectivity Is Modified by a Hypocaloric Mediterranean Diet and Physical Activity in Obese Women
Functional magnetic resonance imaging (fMRI) in the resting state has shown altered brain connectivity networks in obese individuals. However, the impact of a Mediterranean diet on cerebral connectivity in obese patients when losing weight has not been previously explored. The aim of this study was to examine the connectivity between brain structures before and six months after following a hypocaloric Mediterranean diet and physical activity program in a group of sixteen obese women aged 46.31 ± 4.07 years. Before and after the intervention program, the body mass index (BMI) (kg/m2) was 38.15 ± 4.7 vs. 34.18 ± 4.5 (p < 0.02), and body weight (kg) was 98.5 ± 13.1 vs. 88.28 ± 12.2 (p < 0.03). All subjects underwent a pre- and post-intervention fMRI under fasting conditions. Functional connectivity was assessed using seed-based correlations. After the intervention, we found decreased connectivity between the left inferior parietal cortex and the right temporal cortex (p < 0.001), left posterior cingulate (p < 0.001), and right posterior cingulate (p < 0.03); decreased connectivity between the left superior frontal gyrus and the right temporal cortex (p < 0.01); decreased connectivity between the prefrontal cortex and the somatosensory cortex (p < 0.025); and decreased connectivity between the left and right posterior cingulate (p < 0.04). Results were considered significant at a voxel-wise threshold of p ≤ 0.05, and a cluster-level family-wise error correction for multiple comparisons of p ≤ 0.05. In conclusion, functional connectivity between brain structures involved in the pathophysiology of obesity (the inferior parietal lobe, posterior cingulate, temporo-insular cortex, prefrontal cortex) may be modified by a weight loss program including a Mediterranean diet and physical exercise. Be well! JP
July 8th, 2017 at 10:21 pm
Nutrients 2017, 9(7), 725
Plasma Homocysteine and Serum Folate and Vitamin B12 Levels in Mild Cognitive Impairment and Alzheimer’s Disease: A Case-Control Study
Homocysteine (Hcy) is a risk factor for brain atrophy, cognitive impairment, and dementia. Vitamin B12 and folate are cofactors necessary for the methylation of Hcy. However, there is some debate regarding the differing levels of plasma Hcy and serum folate and vitamin B12 among healthy controls, patients with mild cognitive impairment (MCI), and patients with Alzheimer’s disease (AD). This study aimed to evaluate how the levels of plasma Hcy and its biological determinants, folate and vitamin B12, are related to MCI and AD in older Chinese adults. This is a case-control study including 112 subjects with MCI, 89 AD patients and 115 healthy controls. Diagnosis of AD was made according to the NINCDS-ADRDA and MCI with modified Petersen’s criteria. Serum folate and vitamin B12 concentrations were analyzed by radioimmunoassay, and plasma Hcy was assessed by a high-performance liquid chromatography-fluorescence method. Multivariate analysis of regression was used to examine the odds ratio (OR) of MCI or AD with Hcy or vitamin levels. Results have shown that serum folate and vitamin B12 levels were significantly lower, but the plasma Hcy level was higher, in patients with MCI and AD than in healthy controls. Multivariate regression analyses showed that subjects in the lowest folate tertile had significantly higher adjusted ORs for MCI (OR: 3.07; 95% confidence interval [CI]: 1.12, 8.07) and AD (3.42; 95% CI: 1.15, 8.34) compared to subjects in the highest tertile. The highest Hcy tertile was significantly associated with MCI (adjusted OR: 2.81; 95% CI: 1.15, 4.73) and AD (adjusted OR: 3.64; 95% CI: 1.13, 9.04) compared to the lowest tertile. No association existed between low vitamin B12 levels and AD or MCI (p > 0.05). Low blood levels of folate and vitamin B12 and elevated Hcy levels were associated with MCI and AD in older Chinese adults, and the association was stronger for AD.
August 5th, 2017 at 9:30 pm
J Frailty Aging. 2017;6(3):167-171.
Effect of a Combined Tai Chi, Resistance Training and Dietary Intervention on Cognitive Function in Obese Older Women.
Cognitive decline in older adults is a major public health problem and can compromise independence and quality of life. Exercise and diet have been studied independently and have shown to be beneficial for cognitive function, however, a combined Tai Chi, resistance training, and diet intervention and its influence on cognitive function has not been undertaken. The current study used a 12-week non-randomized research design with experiment and control groups to examine the effect of a combined Tai Chi, resistance training, and diet intervention on cognitive function in 25 older obese women. Results revealed improvements in domain specific cognitive function in our sample. Baseline cognitive function was correlated with changes in dietary quality. These findings suggest that Tai Chi and resistance training combined with diet intervention might be beneficial for community-based programs aiming to improve cognitive function.
August 19th, 2017 at 3:35 pm
Int J Food Sci Nutr. 2017 Aug 18:1-8.
Lactobacillus helveticus-fermented milk containing lactononadecapeptide (NIPPLTQTPVVVPPFLQPE) improves cognitive function in healthy middle-aged adults: a randomised, double-blind, placebo-controlled trial.
This study aimed to determine the effects of a Lactobacillus helveticus-fermented milk drink containing lactononadecapeptide (NIPPLTQTPVVVPPFLQPE) on the cognitive function of healthy middle-aged adults. A randomised, double-blind controlled study was conducted in healthy participants who were randomly assigned to receive a L. helveticus-fermented milk drink (190 g/day) or the equivalent amount of a placebo drink once a day for eight weeks. Cognitive function was evaluated using the Japanese version of the repeatable battery for the assessment of neuropsychological status (RBANS) test. There was a statistically significant improvement in the total score, attention score, and delayed memory score of participants who received the L. helveticus-fermented milk drink. There was also a significant difference in the attention score between the placebo and test groups after eight weeks (p = .028). Therefore, supplementation of healthy middle-aged adults with a L. helveticus-fermented milk drink for eight weeks improved both attention and delayed memory.
August 22nd, 2017 at 12:11 pm
Front Aging Neurosci. 2017 Aug 3;9:254.
Effects of Lutein/Zeaxanthin Supplementation on the Cognitive Function of Community Dwelling Older Adults: A Randomized, Double-Masked, Placebo-Controlled Trial.
Background: High levels of xanthophyll carotenoids lutein (L) and zeaxanthin (Z) in the central nervous system have been previously correlated with improved cognitive function in community-dwelling older adults. In this study, we tested the effects of supplementing L and Z on older men and women with a range of baseline cognitive abilities. Objective: The purpose of this study was to determine whether or not supplementation with L+Z could improve cognitive function in community-dwelling, older adults. Design: Double-masked, randomized, placebo-controlled trial. A total of 62 older adults were randomized into groups receiving either 12 mg L+Z or a visually identical placebo. Data from 51 participants (M = 73.7 years) were available for analysis. Retinal L+Z levels (macular pigment optical density, MPOD) were measured psychophysically using heterochromatic flicker photometry as a biomarker of cortical L+Z levels. Cognitive function was measured using the CNS Vital Signs computerized test platform. Results: Participants receiving the active L+Z supplement had statistically significant increases in MPOD (p < 0.03) and improvements in complex attention (p < 0.02) and cognitive flexibility domains (p < 0.04), relative to participants taking the placebo. A trend was also seen for the executive function domain (p = 0.073). In male participants only, supplementation yielded improved composite memory (p = 0.04). Conclusions: Supplementation with L+Z improved cognitive function in community-dwelling, older men and women. Be well! JP
October 30th, 2017 at 8:32 pm
Schizophr Res. 2017 Oct 24.
Omega-3 fatty acid supplementation may prevent loss of gray matter thickness in the left parieto-occipital cortex in first episode schizophrenia: A secondary outcome analysis of the OFFER randomized controlled study.
The aim of the study was to assess changes in cortical thickness related to the use of n-3 polyunsaturated fatty acids (PUFA) as add-on therapy in patients with first episode schizophrenia. A double-blind randomized controlled study was conducted using a 26-week intervention composed of concentrated fish oil containing 2.2g/d of eicosapentaenoic (EPA) and docosahexaenoic acid (DHA) or placebo (olive oil). Participants underwent MRI scanning twice to assess changes in cortical thickness: at the beginning and at the end of intervention. Data of suitable quality was obtained from 29 participants. The T1-weighted images for each participant were analyzed using FreeSurfer methodology for longitudinal pipeline. Significant differences in cortical thickness loss were observed between the groups in the parieto-occipital regions of Brodmann areas 7 and 19 of the left hemisphere, dysfunctions in which may be involved in schizophrenia symptomatology. The results of the study support the previous observations carried out in older individuals and patients with mild cognitive impairment, indicating that n-3 PUFA may have neuroprotective properties, especially at early stages of neurodegenerative diseases, such as schizophrenia. If replicated, the results of the present study may encourage clinicians to consider n-3 PUFA as a promising addition to antipsychotics for long-term treatment of schizophrenia.
December 4th, 2017 at 4:41 pm
J Prev Alzheimers Dis. 2017;4(1):37-43.
Modest Overweight and Healthy Dietary Habits Reduce Risk of Dementia: A Nationwide Survey in Taiwan.
BACKGROUND: Evidence of the associations of dietary habits and body mass index with dementia is inconsistent and limited in East Asian countries.
OBJECTIVE: We aim to explore the associations of dietary habits and body mass index with the odds of dementia.
DESIGN: Cross-sectional observational study.
SETTING: A nationwide, population-based, door-to-door, in-person survey.
PARTICIPANTS: Selected by computerized random sampling from all 19 counties in Taiwan.
MEASUREMENT: Diagnosis of dementia using the criteria recommended by the National Institute on Aging-Alzheimer’s Association. Lifestyle factors, dietary habits and demographic data were compared between normal subjects and participants with dementia.
RESULTS: A total of 10432 residents were assessed, among whom 2049 were classified as having a mild cognitive impairment (MCI), 929 were diagnosed with dementia, and 7035 were without dementia or MCI. After adjustment for age, gender, education, body mass index (BMI), dietary habits, habitual exercises and co-morbidities, including hypertension, diabetes and cerebrovascular diseases, we found inverse associations of dementia with the consumption of fish (OR 0.62, 95% CI 0.41-0.94), vegetables (OR 0.35, 95% CI 0.13-0.95), coffee (OR 0.59, 95% CI 0.35-0.97), green tea (OR 0.51, 95% CI 0.34-0.75) and other types of tea (OR 0.41, 95% CI 0.28-0.60). There was no association between dementia and fruit consumption. Compared with people who had a normal BMI (18 < BMI <= 24), older overweight people (24 < BMI <=30) had a reduced risk of dementia with an adjusted OR of 0.77 (95% CI 0.61-0.96). CONCLUSIONS: Our study provides preliminary evidence that suggests that the consumption of fish, vegetables, tea, and coffee has potential benefits against dementia in East Asian population. Being modestly overweight (nadir risk at BMI = 25) in late life was associated with decreased odds of dementia. The benefit of fruits may be offset by their high sugar content. Be well! JP
December 9th, 2017 at 1:26 am
J Neurol Neurosurg Psychiatry. 2017 Nov 15.
DHA supplementation improves cognitive function via enhancing Aβ-mediated autophagy in Chinese elderly with mild cognitive impairment: a randomised placebo-controlled trial.
BACKGROUND: Higher docosahexaenoic acid (DHA) intake is inversely correlated with relative risk of Alzheimer’s disease. The potential benefits of DHA supplementation in people with mild cognitive impairment (MCI) have not been fully examined.
OBJECTIVE: Our study aimed to assess the effect of a 24-month DHA supplementation on cognitive function and amyloid beta (Aβ)-mediated autophagy in elderly subjects with MCI.
METHODS: This was a randomised, double-blind, placebo-controlled trial in Tianjin, China. A total of 240 individuals with MCI were identified and randomly divided into intervention (DHA 2 g/day, n=120) and control (corn oil as placebo, n=120) groups. Cognitive function and blood Aβ-related biomarkers were measured at baseline, 6, 12, 18 and 24 months. Data were analysed using generalised estimating equation.
RESULTS: A total of 217 participants (DHA: 109, placebo: 108) completed the trial. During the follow-up, scores of full-scale IQ, verbal IQ and subdomains of information and digit span were significantly higher in the intervention group than the convention group (p<0.05). In the intervention group, blood Aβ-42 level and expression of Aβ protein precursor mRNA were decreased (p<0.05), while Beclin-1 and LC3-II levels and expression of LC3-II mRNA were increased (p<0.05).
CONCLUSION: Daily oral DHA supplementation (2 g/day) for 24 months may improve cognitive function and change blood biomarker-related Aβ-mediated autophagy in people with MCI. Larger longer-term confirmatory studies are warranted.
January 11th, 2018 at 8:07 pm
J Med Food. 2018 Jan 10.
Efficacy and Safety of Tremella fuciformis in Individuals with Subjective Cognitive Impairment: A Randomized Controlled Trial.
The efficacy and safety of Tremella fuciformis (TF) as a nutritional supplement were assessed in individuals with subjective cognitive impairment (SCI). Seventy-five individuals with SCI were enrolled in an 8-week, randomized, double-blind, placebo-controlled trial of TF (600 mg/day, n = 30 or 1200 mg/day, n = 30) or placebo (n = 15). The primary outcome measure was changes in total scores of the subjective memory complaint questionnaire. The secondary outcome measures were changes in performance on short-term memory and executive functions, which were assessed using standardized cognitive tests. In addition, voxel-based morphometry was performed to examine the effects of TF on changes in gray matter volume. The individuals in the TF group showed greater improvements in the total scores on the subjective memory complaint questionnaire compared with those in the placebo group. There were also significantly greater improvements in short-term memory and executive functions in the TF group relative to the placebo group. Exploratory analysis demonstrated that there were significant group-by-visit interactions on the left precuneus, right supramarginal gyrus, right middle frontal gyrus, and right postcentral gyrus at corrected P < .05. Overall frequency of adverse events did not differ among high-dose TF (40.4%), low-dose TF (35.1%), and placebo groups (41.4%). The current findings suggest that TF could be safely administered to relieve subjective memory complaints and enhance cognition in individuals with SCI. Be well! JP
March 4th, 2018 at 2:50 pm
Nutrients. 2018 Feb 28;10(3).
Effects of Dietary Supplementation of Astaxanthin and Sesamin on Daily Fatigue: A Randomized, Double-Blind, Placebo-Controlled, Two-Way Crossover Study.
Severe fatigue can negatively affect quality of life, and oxidative stress may play a role in its mechanism. The aim of this study was to evaluate the effect of dietary supplementation of astaxanthin and sesamin (AS), strong food-derived antioxidants, on fatigue. Twenty-four healthy volunteers were supplemented with AS and placebo, each for four weeks. After each supplementation period, participants underwent tasks inducing mental and physical fatigue (visual display terminal task and ergometer task, respectively). Subjective fatigue was evaluated using a visual analogue scale during and after the mental and physical tasks, and daily subjective fatigue was evaluated by the Chalder fatigue questionnaire. Secondary outcomes included other subjective feelings, work efficiency, autonomic nerve activity, levels of an oxidative stress marker (plasma phosphatidylcholine hydroperoxide (PCOOH)) and safety. AS supplementation was associated with significantly improved recovery from mental fatigue compared with placebo. Increased PCOOH levels during mental and physical tasks were attenuated by AS supplementation. No differences between AS and placebo were detected in secondary outcomes, and no adverse effects of AS supplementation were observed. In conclusion, AS supplementation may be a candidate to promote recovery from mental fatigue which is experienced by many healthy people.
October 17th, 2018 at 11:46 pm
J Alzheimers Dis. 2018 Oct 11.
Effects of Meditation and Music-Listening on Blood Biomarkers of Cellular Aging and Alzheimer’s Disease in Adults with Subjective Cognitive Decline: An Exploratory Randomized Clinical Trial.
BACKGROUND: Telomere length (TL), telomerase activity (TA), and plasma amyloid-β (Aβ) levels have emerged as possible predictors of cognitive decline and dementia.
OBJECTIVE: To assess the: 1) effects of two 12-week relaxation programs on TL, TA, and Aβ levels in adults with subjective cognitive decline; and 2) relationship of biomarker changes to those in cognitive function, psychosocial status, and quality of life (QOL).
METHODS: Participants were randomized to a 12-week Kirtan Kriya meditation (KK) or music listening (ML) program and asked to practice 12 minutes/day. Plasma Aβ(38/40/42) and peripheral blood mononuclear cell TL and TA were measured at baseline and 3 months; cognition, stress, sleep, mood, and QOL were assessed at baseline, 3 months, and 6 months.
RESULTS: Baseline blood samples were available for 53 participants (25 KK, 28 ML). The KK group showed significantly greater increases in Aβ40 than the ML group. TA rose in both groups, although increases were significant only among those with higher practice adherence and lower baseline TA. Changes in both TL and TA varied by their baseline values, with greater increases among participants with values ≤50th percentile (ps-interaction <0.006). Both groups improved in cognitive and psychosocial status (ps ≤0.05), with improvements in stress, mood, and QOL greater in the KK group. Rising Aβ levels were correlated with gains in cognitive function, mood, sleep, and QOL at both 3 and 6 months, associations that were particularly pronounced in the KK group. Increases in TL and TA were also correlated with improvements in certain cognitive and psychosocial measures.
CONCLUSION: Practice of simple mind-body therapies may alter plasma Aβ levels, TL, and TA. Biomarker increases were associated with improvements in cognitive function, sleep, mood, and QOL, suggesting potential functional relationships.
November 23rd, 2018 at 6:17 pm
Neurology. 2018 Nov 21.
Long-term intake of vegetables and fruits and subjective cognitive function in US men.
OBJECTIVE: To evaluate the prospective association of long-term intake of vegetables and fruits with late-life subjective cognitive function (SCF).
METHODS: Among 27,842 men with a mean age of 51 years in 1986, we used multinomial logistic regression to examine the relation of vegetable and fruit consumption to future SCF. Average dietary intake was calculated from 5 repeated food frequency questionnaires collected every 4 years until 2002. SCF score was assessed twice (2008 and 2012) using a 6-item questionnaire; validity was supported by strong associations with APO ε4 genotype. We categorized the average of the 2 scores as good, moderate, and poor SCF.
RESULTS: Higher intakes of total vegetables, total fruits, and fruit juice were each significantly associated with lower odds of moderate or poor SCF after controlling for major nondietary factors and total energy intake. The association with total fruit intake was weaker after further adjusting for major dietary factors. In this model, the multivariate odds ratios (95% confidence intervals) for vegetable intake (top vs bottom quintile) were 0.83 (0.76-0.92), p trend <0.001 for moderate SCF and 0.66 (0.55-0.80), p trend <0.001 for poor SCF. For orange juice, compared to <1 serving/mo of intake, daily consumption was associated with a substantially lower odds of poor SCF (0.53 [0.43-0.67], p trend <0.001). Higher consumption of vegetables and fruits 18 to 22 years before SCF assessment was associated with lower odds of poor SCF independent of more proximal intake.
CONCLUSION: Our findings support a long-term beneficial role of vegetable, fruit, and orange juice consumption on SCF.
December 3rd, 2018 at 4:41 pm
Immun Ageing. 2018 Feb 7;15:7.
Effects of a new nutraceutical combination on cognitive function in hypertensive patients.
Background: Chronic increased arterial blood pressure has been associated with executive dysfunction, slowing of attention and mental processing speed, and later with memory deficits. Due to the absence of a concrete therapeutic approach to this pathophysiological process, in the last decades there has been an increasing interest in the use of nutraceuticals, especially those with antioxidant properties, which own strong neuroprotective potential, that may help to improve cognitive function and to delay the onset of dementia.
Results: We evaluated the effects of the treatment with a new nutraceutical preparation containing different molecules with potent antioxidant properties (AkP05, IzzeK®) and placebo on a cohort of thirty-six hypertensive patients. At baseline, neuropsychological evaluation, arterial stiffness and biochemical parameters of the subjects were comparable. After 6 months of treatment, there was a significant reduction of the augmentation index in the AkP05-treated group. Moreover, the measurement of cognitive function, evaluated with MoCA test and Word Match Testing, showed a significant improvement in patients receiving the active treatment. In addition, the group treated with nutraceutical reached a better Stroop test score, while subjects that received placebo did not showed any improvement. Finally, a positive relationship between SBP variation and the psychometric assessment with the EQ-VAS scale was observed only in the active treatment group.
Conclusions: In this study, we demonstrated that the therapy with a new nutraceutical preparation is able to significantly increase the scores of important neuropsychological tests in hypertensive patients already on satisfactory blood pressure control. Although future studies are needed to better characterize the molecular mechanisms involved, these results candidate the new nutraceutical combination as a possible therapeutic strategy to support the cerebrovascular functions and delay the onset of dementia in hypertensive patients.
December 10th, 2018 at 4:11 pm
J Gerontol B Psychol Sci Soc Sci. 2018 Nov 28.
Psychophysiological effects of Dance Movement Therapy and physical exercise on older adults with mild dementia: A randomized controlled trial.
Objectives: Dementia interferes with older adults’ functioning in cognitive, daily, psychosocial, and neuroendocrine domains. The present study examined the psychophysiological effects of dance movement therapy (DMT) and physical exercise for older adults with dementia.
Methods: This randomized controlled trial recruited 204 older adults diagnosed with mild dementia into the DMT, exercise, or waitlist control group. Both DMT and exercise interventions had similar intensity and comprised 24 hours of intervention that spanned over 12 weeks. All participants completed self-report questionnaires on psychosocial well-being, daily functioning, neurocognitive assessments, and salivary cortisol measures at baseline and three follow-up measurements over one year.
Results: The DMT group showed significant decreases in depression, loneliness, and negative mood (d = 0.33 – 0.42, p < 0.05) and improved daily functioning (d = 0.40, p < 0.01) and diurnal cortisol slope (d = 0.30, p < 0.01). Only the effects on daily functioning and cortisol slope remained at 1-year follow-up. The exercise group of matched intensity showed no significant effects on the outcomes. Discussion: The study findings support the potential utility of DMT as a multifaceted intervention for improving various aspects of functioning in older adults with declining cognitive abilities. The lack of beneficial effects for our exercise intervention and long-term DMT effects highlights the need to maintain persistent levels of exercise with adequate intensity and duration. Be well! JP
January 2nd, 2019 at 10:52 pm
Clin Nutr. 2018 Dec 22.
The effect of Atlantic salmon consumption on the cognitive performance of preschool children – A randomized controlled trial.
BACKGROUND AND AIMS: Long chain polyunsaturated n-3 fatty acids (LC-PUFA) are of functional and structural importance for brain development. Observational studies have shown positive relations between fatty fish consumption and cognitive performance in children, but Results from intervention studies using supplementary n-3 LC-PUFA are conflicting. Salmon is a good source of n-3 LC-PUFA, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). We tested the hypothesis that an increased dietary salmon intake results in better cognitive outcomes than a meat based diet.
METHODS: Children (n = 205, age 4-6 years) in this trial were individually randomized to eating meals containing farmed Atlantic salmon or meat three times weekly for 16 weeks. Pre- and post-intervention a cognitive test (Wechsler Preschool and Primary Scale of Intelligence, 3rd edition, WPPSI-III) and a fine-motor coordination test (Nine Hole Peg Test, 9-HPT) were performed. Biochemical analyses included glycerophospholipid fatty acid profiles in plasma and cheek cells, serum 25-hydroxyvitamin D, and urinary iodine concentration. Dietary intake before and during the study were determined using food frequency questionnaires.
RESULTS: Intakes of EPA, DHA, vitamin D and iodine were higher in the salmon than the meat group, but on biomarker level only EPA and DHA increased significantly in the salmon group compared to the meat group (p < 0.001). In general linear models no significant differences between the intervention groups were found in the scale scores of the WPPSI-III tests and the 9-HPT. In analyses of the raw scores, the salmon group showed significantly better improvement in two of the eight raw scores compared to the meat group (symbol search p = 0.038, picture concepts p = 0.047). CONCLUSIONS: Intake of farmed Atlantic salmon led to a greater increase of the raw scores of the picture concept and symbol search subtests, while in the six other subtests raw scores were not different between the groups. This might indicate a modest positive association of salmon intake with the performance of preschool children in some subtests evaluating fluid intelligence but does not suggest an influence on global IQ development. Be well! JP
February 1st, 2019 at 2:05 pm
Nutrition. 2018 Nov 24;61:77-83.
Effects of seafood consumption and toenail mercury and selenium levels on cognitive function among American adults: 25 y of follow up.
OBJECTIVES: The aim of this study was to examine the longitudinal association between seafood and intake of long-chain ω-3 polyunsaturated fatty acids (LCω-3 PUFA) and cognitive function and to explore the possible effect modifications owing to mercury (Hg) and selenium (Se) levels.
METHODS: Participants (N = 3231) from the CARDIA (Coronary Artery Risk Development in Young Adults) study underwent baseline examination and were reexamined in eight follow-up visits. Diet was assessed at baseline and in exam years 7 and 20. Toenail Hg and Se were measured at exam year 2. Cognitive function was measured at exam year 25 using three tests: Rey Auditory Verbal Learning Test (RAVLT), Digit Symbol Substitution Test (DSST), and the Stroop test. The general linear regression model was used to examine cumulative average intakes of LCω-3 PUFA and seafood in relation to the cognitive test scores; and to explore the possible effect modifications caused by Hg and Se.
RESULTS: LCω-3 PUFA intake was significantly associated with better performance in the DSST test (quintile 5 versus quintile 1; mean difference = 1.74; 95% confidence interval, 0.19-3.29; Ptrend, 0.048]), but not in the RAVLT and Stroop tests. Similar results were observed for intakes of eicosapentaenoic acid, docosahexaenoic acid, and non-fried seafood. The observed associations were more pronounced in participants with body mass index ≥25 kg/m2, but not significantly modified by toenail Hg or Se.
CONCLUSION: This longitudinal study supported the hypothesis that LCω-3 PUFA or non-fried seafood intake is associated with better cognitive performance in psychomotor speed among US adults, especially those who are overweight or obese.
February 11th, 2019 at 11:29 pm
Geroscience. 2019 Feb 9.
Astaxanthin supplementation modulates cognitive function and synaptic plasticity in young and aged mice.
The incidence of neurodegenerative disorders and cognitive impairment is increasing. Rising prevalence of age-related medical conditions is associated with a dramatic economic burden; therefore, developing strategies to manage these health concerns is of great public health interest. Nutritionally based interventions have shown promise in treatment of these age-associated conditions. Astaxanthin is a carotenoid with reputed neuroprotective properties in the context of disease and injury, while emerging evidence suggests that astaxanthin may also have additional biological activities relating to neurogenesis and synaptic plasticity. Here, we investigate the potential for astaxanthin to modulate cognitive function and neural plasticity in young and aged mice. We show that feeding astaxanthin to aged mice for 1 month improves performance on several hippocampal-dependent cognitive tasks and increases long-term potentiation. However, we did not observe an alteration in neurogenesis, nor did we observe a change in microglial-associated IBA1 immunostaining. This demonstrates the potential for astaxanthin to modulate neural plasticity and cognitive function in aging.
February 19th, 2019 at 3:30 pm
J Alzheimers Dis. 2019 Feb 11.
The Association between Mushroom Consumption and Mild Cognitive Impairment: A Community-Based Cross-Sectional Study in Singapore.
We examined the cross-sectional association between mushroom intake and mild cognitive impairment (MCI) using data from 663 participants aged 60 and above from the Diet and Healthy Aging (DaHA) study in Singapore. Compared with participants who consumed mushrooms less than once per week, participants who consumed mushrooms >2 portions per week had reduced odds of having MCI (odds ratio = 0.43, 95% CI 0.23-0.78, p = 0.006) and this association was independent of age, gender, education, cigarette smoking, alcohol consumption, hypertension, diabetes, heart disease, stroke, physical activities, and social activities. Our cross-sectional data support the potential role of mushrooms and its bioactive compounds in delaying neurodegeneration.
March 9th, 2019 at 2:32 pm
Conscious Cogn. 2019 Mar 5;70:57-69.
Coffee cues elevate arousal and reduce level of construal.
Coffee and tea are two beverages commonly-consumed around the world. Therefore, there is much research regarding their physiological effects. However, less is known about their psychological meanings. Derived from a predicted lay association between coffee and arousal, we posit that exposure to coffee-related cues should increase arousal, even in the absence of actual ingestion, relative to exposure to tea-related cues. We further suggest that higher arousal levels should facilitate a concrete level of mental construal as conceptualized by Construal Level Theory. In four experiments, we find that coffee cues prompted participants to see temporal distances as shorter and to think in more concrete, precise terms. Both subjective and physiological arousal explain the effects. We situate our work in the literature that connects food and beverage to cognition or decision-making. We also discuss the applied relevance of our results as coffee and tea are among the most prevalent beverages globally.
March 13th, 2019 at 11:58 am
J Alzheimers Dis. 2019 Mar 2.
Preliminary Report on the Feasibility and Efficacy of the Modified Atkins Diet for Treatment of Mild Cognitive Impairment and Early Alzheimer’s Disease.
Ketone bodies, the products of fat metabolism, are a source of energy for the brain and are available even when glucose supplies are inadequate (such as with severe carbohydrate deprivation) or its metabolism is faulty (as it is in Alzheimer’s disease). This phase I/II randomized clinical trial examined the feasibility of using a modified Atkins diet (MAD) to induce ketogenesis in persons with mild cognitive impairment (MCI) or early AD, and the effect of this diet on memory and other clinical outcomes. In the first 2.5 years of active recruitment, only 27 eligible and willing patients enrolled. After extensive assessment and education, they and their study partners were randomly assigned for 12 weeks to either the MAD or the National Institute on Aging (NIA) recommended diet for seniors. As of April 2018, 9 patients in the MAD arm and 5 in the NIA arm have completed the trial. In spite of extensive teaching, coaching, and monitoring, adherence to both diets was only fair. Among those in the MAD arm who generated at least trace amounts of urinary ketones, there was a large (effect size = 0.53) and statistically significant (p = 0.03) increase in Memory Composite Score between the baseline and week-6 assessment. MAD participants also reported increased energy between baseline and week-6 assessment. Despite challenges to implementing this trial, resulting in a small sample, our preliminary data suggest that the generation of even trace ketones might enhance episodic memory and patient-reported vitality in very early AD.
March 22nd, 2019 at 6:32 pm
J Alzheimers Dis. 2019 Mar 11.
Intake of Meat, Fish, Fruits, and Vegetables and Long-Term Risk of Dementia and Alzheimer’s Disease.
BACKGROUND: The links between diet and the risk of dementia have never been studied considering the possibility of protopathic bias (i.e., reverse causation).
OBJECTIVE: We aimed to examine the relationship between consumption frequency of meat, fish, fruits, and vegetables and long-term risk of dementia and Alzheimer’s disease (AD), by taking into account this possibility.
METHODS: We analyzed data of 5,934 volunteers aged 65 and over from the Three-city study who were followed every 2 to 4 years for 12 years. Dietary habits were assessed at inclusion using a brief food frequency questionnaire. The presence of symptoms of dementia was investigated at each follow-up visit. To limit the risk of protopathic bias, a 4-year lag window between exposure and disease assessment was implemented by excluding from the analyses all dementia cases that occurred during the first four years after inclusion. Analyses were performed using a Cox proportional hazard model and were adjusted for socio-demographic, lifestyle, and health factors.
RESULTS: The average follow-up time was 9.8 years. During this period, 662 cases of dementia, including 466 of AD, were identified. After adjustment, only low meat consumption (≤1 time/week) was associated with an increased risk of dementia and AD compared with regular consumption (≥4 times/week) (HR = 1.58 95% CI = [1.17-2.14], HR = 1.67 95% CI = [1.18-2.37], respectively). No association was found between the consumption of fish, raw fruits, or cooked fruits and vegetables and the risk of dementia or AD.
CONCLUSION: These findings suggest very low meat consumption increases the long-term risk of dementia and AD, and that a protopathic bias could have impacted finding from previous studies.