Individually modifiable risk factors to ameliorate cognitive aging: a systematic review and meta-analysis

Mediterranean diet related to 3-year incidence of cognitive decline: results from a cohort study in Chinese rural elders

OBJECTIVE

This study aims to examine the effect of the Mediterranean diet (MeDi) on cognitive decline among the Chinese elderly with a 3-year follow-up.

METHODS

This study is divided into two waves: wave-1 January 2019 to June 2019 (n = 2313); wave-2 January 2022 to March 2022 (n = 1648). MeDi scores were calculated from the Mediterranean Diet Adherence Screener (MEDAS), with the scoring of low compliance (0-6 points) and high compliance (7-14 points). The Mini-Mental State Examination (MMSE) was used to assess cognitive function. An MMSE score dropping ≥ 2 points from baseline was defined as cognitive decline. The relationships between MeDi score and cognitive decline were analyzed by linear regression models or Binary logistic regression.

RESULTS

During the 3-year follow-up, 23.8% of patients exhibited cognitive decline. The study revealed a significant difference in MMSE score changes between low and high MeDi adherence groups (p < 0.001). MeDi score was negatively correlated with cognitive deterioration (β = -0.020, p = 0.026). MeDi score was only negatively associated with cognitive decline in the female subgroup aged ≥65 years (β = -0.034, p = 0.033). The food beans (OR = 0.65, 95%CI:0.51, 0.84), fish (OR = 0.72, 95%CI:0.54, 0.97), and cooked vegetables (OR = 0.68, 95%CI:0.53, 0.84) were protective factors for cognitive decline.

CONCLUSIONS

This study suggests that greater adherence to the MeDi is linked to a reduced risk of cognitive decline in elderly people. However, this is found only in women who are 65 years old or older. It also found long-term adherence to beans, fish, and vegetables are more effective in improving cognitive function.

Health Outcomes Associated with Olive Oil Intake: An Umbrella Review of Meta-Analyses

Several studies suggested a negative association between olive oil (OO) consumption and the risk of several chronic diseases. However, an attempt to systematically search, organize, and evaluate the existing evidence on all health outcomes associated with OO consumption is lacking. The objective of this review is to describe the multiple health outcomes associated with OO consumption. The Medline, Scopus, and Web of Science databases were searched through 5 April 2024. The selected studies met all of the following criteria: (1) a meta-analysis of both observational (case-control and cohort studies) and interventional studies (trials), (2) an evaluation of the association between OO consumption, mortality, and/or the incidence of non-communicable/chronic degenerative diseases, and (3) a study population ≥18 years old. Two independent reviewers extracted the relevant data and assessed the risk of bias of individual studies. The PRISMA statement and guidelines for the Integration of Evidence from Multiple Meta-Analyses were followed. The literature search identified 723 articles. After selection, 31 articles were included in this umbrella review. The primary health benefits of OO were observed in cardiovascular diseases and risk factors, cancer, mortality, diabetes, and specific biomarkers related to anthropometric status and inflammation. As a key component of the Mediterranean diet, OO can be considered a healthy dietary choice for improving positive health outcomes.

Human gut microbiome, diet, and mental disorders

Diet is one of the most important external factor shaping the composition and metabolic activities of the gut microbiome. The gut microbiome plays a crucial role in host health, including immune system development, nutrients metabolism, and the synthesis of bioactive molecules. In addition, the gut microbiome has been described as critical for the development of several mental disorders. Nutritional psychiatry is an emerging field of research that may provide a link between diet, microbial function, and brain health. In this study, we have reviewed the influence of different diet types, such as Western, Mediterranean, vegetarian, and ketogenic, on the gut microbiota composition and function, and their implication in various neuropsychiatric and psychological disorders.

Personality predictors of dementia diagnosis and neuropathological burden: An individual participant data meta-analysis

INTRODUCTION

The extent to which the Big Five personality traits and subjective well-being (SWB) are discriminatory predictors of clinical manifestation of dementia versus dementia-related neuropathology is unclear.

METHODS

Using data from eight independent studies (Ntotal = 44,531; Ndementia = 1703; baseline Mage = 49 to 81 years, 26 to 61% female; Mfollow-up range = 3.53 to 21.00 years), Bayesian multilevel models tested whether personality traits and SWB differentially predicted neuropsychological and neuropathological characteristics of dementia.

RESULTS

Synthesized and individual study results indicate that high neuroticism and negative affect and low conscientiousness, extraversion, and positive affect were associated with increased risk of long-term dementia diagnosis. There were no consistent associations with neuropathology.

DISCUSSION

This multistudy project provides robust, conceptually replicated and extended evidence that psychosocial factors are strong predictors of dementia diagnosis but not consistently associated with neuropathology at autopsy.

HIGHLIGHTS

N(+), C(-), E(-), PA(-), and NA(+) were associated with incident diagnosis. Results were consistent despite self-report versus clinical diagnosis of dementia. Psychological factors were not associated with neuropathology at autopsy. Individuals with higher conscientiousness and no diagnosis had less neuropathology. High C individuals may withstand neuropathology for longer before death.

The Mediating Role of Cortical Atrophy on the Relationship between the Resilience Index and Cognitive Function: Findings from the Healthy Brain Initiative

Background

Lifestyle factors are linked to differences in brain aging and risk for Alzheimer's disease, underscored by concepts like 'cognitive reserve' and 'brain maintenance'. The Resilience Index (RI), a composite of 6 factors (cognitive reserve, physical and cognitive activities, social engagement, diet, and mindfulness) provides such a holistic measure.

Objective

This study aims to examine the association of RI scores with cognitive function and assess the mediating role of cortical atrophy.

Methods

Baseline data from 113 participants (aged 45+, 68% female) from the Healthy Brain Initiative were included. Life course resilience was estimated with the RI, cognitive performance with Cognivue®, and brain health using a machine learning derived Cortical Atrophy Score (CAS). Mediation analysis probed the relationship between RI, cognitive outcomes, and cortical atrophy.

Results

In age and sex adjusted models, the RI was significantly associated with CAS (β= -0.25, p = 0.006) and Cognivue® scores (β= 0.32, p < 0.001). The RI-Cognivue® association was partially mediated by CAS (β= 0.07; 95% CI [0.02, 0.14]).

Conclusions

Findings revealed that the collective effect of early and late-life lifestyle resilience factors on cognition are partially explained by their association with less brain atrophy. These findings underscore the value of comprehensive lifestyle assessments in understanding the risk and progression of cognitive decline and Alzheimer's disease in an aging population.

Racial differences in the effect of APOE-ε4 genotypes on trail making test B in Alzheimer's disease: A longitudinal study

OBJECTIVES

The trail making test part B (TMT-B) evaluates executive functions, memory, and sensorimotor functions. No previous study was found to examine the longitudinal effect of APOE-ε4 genotypes on the TMT-B scores in Alzheimer's disease (AD) across racial groups.

METHODS

This study used the data from Alzheimer's Disease Neuroimaging Initiative (ADNI): 382 participants with AD, 503 with cognitive normal (CN), 1293 with mild cognitive impairment (MCI) at baseline and follow-up of four years. The multivariable linear mixed model was used to investigate the effect of APOE-ε4 genotypes on changes in TMT-B scores.

RESULTS

Compared with Whites, African Americans (AA) and Hispanics had higher TMT-B scores (poor cognitive function). Furthermore, Whites subjects with 1 or 2 APOE-ε4 alleles had significantly higher TMT-B scores compared with individuals without APOE-ε4 allele at baseline and four follow-up visits; however, no differences in TMT-B were found between APOE-ε4 alleles in the Hispanic and AA groups. No APOE-ε4 by visit interactions was found for 3 racial groups. Stratified by AD diagnosis, the APOE-ε4 allele was associated with TMT-B scores only in the MCI group, while there were significant interactions for visit by education, APOE-ε4 allele, and the Mini Mental State Examination (MMSE) score in the MCI group. In addition, TMT-B was significantly correlated with the MMSE, AD Assessment Scale-cognitive subscale 13 (ADAS13), tTau, pTau, Aβ42, and hippocampus.

CONCLUSIONS

APOE-ɛ4 allele is associated with TMT-B scores in Whites subjects, but not in the Hispanic and AA groups. APOE-ε4 showed interaction with visit in the MCI group.

The effects of olive oil consumption on cognitive performance: a systematic review

Introduction

The Mediterranean diet is marked by the regular intake of olive oil, which may play a role in preventing and protecting against cognitive deterioration and dementia. The strength of these effects have been examined by several recent randomized controlled trials (RCTs), but their findings have not been consistent. In light of this inconsistency, the present study performed a systematic review to examine the relationship between the consumption of olive oil and cognition.

Methods

The Web of Science, Scopus, PubMed, and Google Scholar were systematically searched up to August 11, 2023. The review included RCTs, cross-sectional studies, cohort studies and case-control studies that explored the impact of olive oil consumption on cognitive performance among those older than 55 years old. Studies were excluded if they employed a design other than those mentioned above, involved participants under 55 years old, or did not specifically examine the cognitive effects of olive oil consumption. The quality of the included studies were measured using the Cochrane risk-of-bias tool and the Newcastle Ottawa Scale checklists.

Results

Eleven studies were identified, which were comprised of four cross-sectional studies, four prospective cohort studies and three RCTs. The cohort studies and RCTs consistently found that olive oil consumption had a favorable effect on cognitive performance across a number of cognitive domains over time. Similarly, all of the cross-sectional studies reported that the consumption of olive oil was positively associated with cognitive health.

Conclusion

The consumption of olive oil was found to enhance cognitive functioning and to reduce cognitive decline. Further large-scale investigations are required to strengthen this conclusion.

Adherence to the Mediterranean diet and waist-to-hip ratio in middle-aged postmenopausal women are the main factors associated with semantic verbal fluency 12 years later

Few studies have analized the effect of vascular risk factors and lifestyle habits affecting the middle age of postmenopausal women on later cognitive performance in old age. We have carried out an observational study to identify those factors and whether they differ from those acting in men. Postmenopausal women and males, both aged 40-60  years old at recruitment, from a community dwelling cohort were included. Data for this study were collected from the first visit at recruitment (2001 to 2005). Participants were interviewed with a questionnaire on their health-related antecedents and underwent a physical exam. The cohort was contacted again for a new presential visit between 2014 and 2015. A semantic verbal fluency test was included in this new visit protocol as a brief measure of cognition. Besides educational attainment, Mediterranean diet adherence 20th percentile (OR = 1.93; 95%CI = 1.07-3.47) and waist to hip ratio 80th percentile (OR = 1.81; 95%CI = 1.10-2,98) were the main factors associated to low semantic fluency performance in postmenopausal women, while declared diabetes mellitus (OR = 2.24; 95%CI = 1.16-4,33), HOMA 2 insulin resistance index (OR = 1.77; 95%CI =1.04-3,02), light physical activity in leisure time (OR = 0.41; 95%CI = 0.19-0,93) and recommended moderate to vigorous physical activity (OR = 2.09; 95%CI = 1.23-3.56) did in men. Factors in middle age that explain semantic verbal fluency in old age are different between postmenopausal women and men. Menopause related fat redistribution may be a precondition for other vascular risk factors. The effect of Mediterranean diet on cognition deserves new specific studies centered on postmenopausal women as group.

The Effects of the Mediterranean Diet on Health and Gut Microbiota

The Mediterranean Diet (MD) is plant-based and consists of multiple daily portions of vegetables, fruit, cereals, and olive oil. Although there are challenges with isolating the MD from the typical Mediterranean lifestyle and culture (including prolonged 'social' meals and siestas), much evidence supports the health benefits of the MD that include improved longevity, reduced metabolic risk of Diabetes Mellitus, obesity, and Metabolic Syndrome, reduced risk of malignancy and cardiovascular disease, and improved cognitive function. The MD is also associated with characteristic modifications to gut microbiota, mediated through its constituent parts (primarily dietary fibres, extra virgin olive oil, and polyunsaturated fatty acids [including ω-3]). These include enhanced growth of species that produce short-chain fatty acids (butyrate), such as Clostridium leptum and Eubacterium rectale, enhanced growth of Bifidobacteria, Bacteroides, and Faecalibacterium prausnitzii species, and reduced growth of Firmicutes and Blautia species. Such changes in gut microbiota are known to be associated favourably with inflammatory and oxidative status, propensity for malignancy and overall metabolic health. A key challenge for the future is to explore the extent to which the health benefits of the MD are mediated by such changes to gut microbiota. The MD confers both health and environmental benefits. Adoption of the MD should perhaps be encouraged and facilitated more generally and not just restricted to populations from Mediterranean regions. However, there are key challenges to this approach that include limited perennial availability of the constituent parts of the MD in some non-Mediterranean regions, intolerability of a high-fibre diet for some people, and potential cultural disconnects that juxtapose some traditional (including Western) diets with the MD.

Socioeconomic and Contextual Differentials in Memory Decline: A Cross-Country Investigation Between England and China

OBJECTIVES

Although cognitive functioning is strongly associated with biological changes in the brain during the aging process, very little is known about the role of sociocultural differentials between the western and eastern parts of the world. We examined the associations between individual socioeconomic markers (e.g., education, household wealth) and contextual levels characteristics (e.g., urbanicity) with memory performance and memory decline over up to 8 years of follow-up in England and China.

METHODS

The analytical samples included participants aged 50+ from the English Longitudinal Study of Aging (n = 6,687) and the China Health and Retirement Longitudinal Study (n = 10,252). Mixed linear models were employed to examine the association between baseline individual socioeconomic markers (education, wealth) and contextual-level characteristics (urbanicity) on the change in memory over time.

RESULTS

Our analyses showed that higher education and wealth were associated with better baseline memory in both England and China. Still, the impact of contextual-level characteristics such as urbanicity differed between the 2 countries. For English individuals, living in a rural area showed an advantage in memory, while the opposite pattern was observed in China. Memory decline appeared to be socioeconomically patterned by higher education, wealth, and urbanicity in China but not in England.

DISCUSSION

Our findings highlight substantial socioeconomic and contextual inequity in memory performance in both England and China, as well as in the rate of memory decline primarily in China. Public health strategies for preventing memory decline should target the socioeconomic gaps at the individual and contextual levels to protect those particularly disadvantaged.

Vitamin D, Menopausal Health and COVID-19: Critical Appraisal of Current Data

Inconsistency exists across studies conducted in postmenopausal women regarding the effect of vitamin D deficiency (VDD) and supplementation on several aspects of menopausal health, such as fractures, vasomotor symptomatology, cardiovascular disease (CVD), cancer and infections, including coronavirus disease 2019 (COVID-19). The aim of this review is to critically summarize the evidence provided by observational studies and randomized controlled trials (RCTs) of vitamin D supplementation in postmenopausal women with VDD. Observational studies have found that VDD is associated with an increased risk of falls and fractures after the menopause. VDD also has a negative effect on menopausal symptomatology. VDD, especially its severe form, is associated with an increased risk of CVD risk factors and CVD events. VDD is associated with increased risk and mortality from several cancer types and risk of infections. The evidence from RCTs regarding the effect of vitamin D supplementation on falls, fractures, menopausal symptoms, cardiovascular disease, cancer and infections is not robust. Thus, skeletal health may benefit only when vitamin D is co-administered with calcium, especially in those ≥70 years old and with severe VDD. There is no evidence of a favorable effect on menopausal symptoms or risk of CVD or cancer, except for a modest reduction in cancer-related mortality. Inconsistency still exists regarding its effect on infection risk, disease severity and mortality due to COVID-19.

Design Considerations for an Exergame-Based Training Intervention for Older Adults With Mild Neurocognitive Disorder: Qualitative Study Including Focus Groups With Experts and Health Care Professionals and Individual Semistructured In-depth Patient Interviews

BACKGROUND

Exergames have attracted growing interest in the prevention and treatment of neurocognitive disorders. The most effective exergame and training components (ie, exercise and training variables such as frequency, intensity, duration, or volume of training and type and content of specific exergame scenarios) however remain to be established for older adults with mild neurocognitive disorders (mNCDs). Regarding the design and development of novel exergame-based training concepts, it seems of crucial importance to explicitly include the intended users' perspective by adopting an interactive and participatory design that includes end users throughout different iterative cycles of development.

OBJECTIVE

This study aimed to determine the capabilities, treatment preferences, and motivators for the training of older adults with mNCD and the perspectives of individuals on training goals and settings and requirements for exergame and training components.

METHODS

A qualitative study including expert focus groups and individual semistructured in-depth patient interviews was conducted. Data were transcribed to a written format to perform qualitative content analysis using QCAmap software.

RESULTS

In total, 10 experts and health care professionals (80% females) and 8 older adults with mNCD (38% females; mean age 82.4, SD 6.2 years) were recruited until data saturation was observed.

CONCLUSIONS

The psychosocial consequences of patients' self-perceived cognitive deterioration might be more burdensome than the cognitive changes themselves. Older adults with mNCD prefer integrative forms of training (such as exergaming) and are primarily motivated by enjoyment or fun in exercising and the effectiveness of the training. Putting the synthesized perspectives of training goals, settings, and requirements for exergames and training components into context, our considerations point to opportunities for improvement in research and rehabilitation, either by adapting existing exergames to patients with mNCDs or by developing novel exergames and exergame-based training concepts specifically tailored to meet patient requirements and needs.

Can Nutrients and Dietary Supplements Potentially Improve Cognitive Performance Also in Esports?

Factors influencing brain function and cognitive performance can be critical to athletic performance of esports athletes. This review aims to discuss the potential beneficial effects of micronutrients, i.e., vitamins, minerals and biologically active substances on cognitive functions of e-athletes. Minerals (iodine, zinc, iron, magnesium) and vitamins (B vitamins, vitamins E, D, and C) are significant factors that positively influence cognitive functions. Prevention of deficiencies of the listed ingredients and regular examinations can support cognitive processes. The beneficial effects of caffeine, creatine, and probiotics have been documented so far. There are many plant products, herbal extracts, or phytonutrients that have been shown to affect precognitive activity, but more research is needed. Beetroot juice and nootropics can also be essential nutrients for cognitive performance. For the sake of players’ eyesight, it would be useful to use lutein, which, in addition to improving vision and protecting against eye diseases, can also affect cognitive functions. In supporting the physical and mental abilities of e-athletes the base is a well-balanced diet with adequate hydration. There is a lack of sufficient evidence that has investigated the relationship between dietary effects and improved performance in esports. Therefore, there is a need for randomized controlled trials involving esports players.

Making the Best Out of IT: Design and Development of Exergames for Older Adults With Mild Neurocognitive Disorder - A Methodological Paper

Background: Utilizing information technology (IT) systems, for example in form of computerized cognitive screening or exergame-based (also called active videogames) training, has gained growing interest for supporting healthy aging and to detect, prevent and treat neurocognitive disorders (NCD). To ameliorate the effectiveness of exergaming, the neurobiological mechanisms as well as the most effective components for exergame-based training remain to be established. At the same time, it is important to account for the end-users' capabilities, preferences, and therapeutic needs during the design and development process to foster the usability and acceptance of the resulting program in clinical practice. This will positively influence adherence to the resulting exergame-based training program, which, in turn, favors more distinct training-related neurobiological effects. Objectives and Methods: This methodological paper describes the design and development process of novel exergame-based training concepts guided by a recently proposed methodological framework: The 'Multidisciplinary Iterative Design of Exergames (MIDE): A Framework for Supporting the Design, Development, and Evaluation of Exergames for Health' (Li et al., 2020). Case Study: A step-by-step application of the MIDE-framework as a specific guidance in an ongoing project aiming to design, develop, and evaluate an exergame-based training concept with the aim to halt and/or reduce cognitive decline and improve quality of life in older adults with mild neurocognitive disorder (mNCD) is illustrated. Discussion and Conclusion: The development of novel exergame-based training concepts is greatly facilitated when it is based on a theoretical framework (e.g., the MIDE-framework). Applying this framework resulted in a structured, iterative, and evidence-based approach that led to the identification of multiple key requirements for the exergame design as well as the training components that otherwise may have been overlooked or neglected. This is expected to foster the usability and acceptance of the resulting exergame intervention in "real life" settings. Therefore, it is strongly recommended to implement a theoretical framework (e.g., the MIDE-framework) for future research projects in line with well-known checklists to improve completeness of reporting and replicability when serious games for motor-cognitive rehabilitation purposes are to be developed.

Does older adults' cognition particularly suffer from stress? A systematic review of acute stress effects on cognition in older age

This literature review provides the first comprehensive qualitative and quantitative systematic synthesis of acute laboratory stress effects on older adults' cognition by specifying the direction and magnitude of those effects both overall and for different cognitive processes separately. A systematic literature search was performed, and effect sizes estimated whenever possible. We found meta-analytical evidence that stress has negative effects on older adults' verbal fluency (g_adj = -0.53, 95 % CI [-2.70, 1.63]), null-to-negative effects on episodic memory (g_adj = -0.26, 95 % CI [-0.44, -0.08]), null effects on executive functions (g_adj = 0.07, 95 % CI [-0.31, 0.46]), and enhancing effects on working memory (g_adj = 0.16, 95 % CI [-0.01, 0.33]). Relating these findings to those in young adults, notable differences emerged for some cognitive functions, such as opposing effects on working memory between age groups. Our review further reveals that stress effects on older adults' memory retention, associative memory, prospective memory, interference control or cognitive flexibility are heavily understudied. We provide a conceptual and methodological framework for future studies in older adults.

A Comprehensive Review of Hass Avocado Clinical Trials, Observational Studies, and Biological Mechanisms

This first comprehensive review of fresh Hass avocados includes 19 clinical trials, five observational studies, and biological mechanisms. We identified four primary avocado health effects: (1) reducing cardiovascular disease risk in healthy overweight or obese adults with dyslipidemia by lowering non-HDL-C profiles, triglycerides, LDL oxidation, small atherogenic LDL particles and promoting postprandial vascular endothelial health for better peripheral blood flow; (2) lowering the risk of being overweight or obese, supporting weight loss, and reducing visceral fat tissue in overweight or obese women; (3) improving cognitive function in older normal-weight adults and in young to middle age overweight or obese adults especially in frontal cortex executive function; and (4) stimulating improved colonic microbiota health in overweight or obese adults by promoting healthier microflora and fecal metabolites. We also identified a unique combination of four Hass avocado nutritional features that appear to be primarily responsible for these health effects: (1) a 6 to 1 unsaturated (rich in oleic acid) to saturated fat ratio similar to olive oil; (2) a source of multifunctional prebiotic and viscous fiber; (3) a relatively low energy density of 1.6 kcal/g (79% of edible Hass avocado weight consists of water and fiber with a creamy, smooth texture); and (4) its oleic acid and water emulsion increases carotenoid absorption from low-fat fruits and vegetables (e.g., salsa or salad) when consumed with avocados. They are also a good source of micronutrients and polyphenols, and are very low in sodium and available carbohydrates supporting secondary health and wellness benefits. Hass avocado health effects are best demonstrated when consumed in a healthy dietary plan such as the Mediterranean diet. More extensive and longer clinical trials are needed to further enhance our understanding of the Hass avocado’s health effects.

Low Serum Testosterone Concentrations Are Associated With Poor Cognitive Performance in Older Men but Not Women

Objective: Current evidence on the association between serum testosterone and cognitive performance has been inconsistent, especially in older adults. To investigate the associations between serum testosterone and cognitive performance in a nationally representative sample of older men and women. Methods: We used data from the National Health and Nutrition Examination Survey (NHANES) 2011-2014. 1,303 men and 1,349 women aged 60 years or older were included in the study. Serum total testosterone was preformed via isotope dilution liquid chromatography tandem mass spectrometry (ID-LC-MS/MS) method. Free testosterone was calculated by Vermeulen's formula. Cognitive performance was evaluated by the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) test, Animal Fluency test, and Digit Symbol Substitution Test (DSST). Binary logistic regression and restricted cubic spline models were applied to evaluate the association of testosterone and cognitive performance. Results: In men, higher concentrations of total testosterone were associated with better performance on CERAD test (OR = 0.51; 95%CI = 0.27-0.95) and DSST (OR = 0.54; 95%CI = 0.30-0.99) in adjusted group. Similarly, higher concentrations of free testosterone were associated with better performance on CERAD test (OR = 0.32; 95%CI = 0.17-0.61) and DSST (OR = 0.41; 95%CI = 0.17-0.96) in men. These associations were not seen in women. Conclusion: Serum testosterone concentrations were inversely associated with cognitive performance in older men but not women in the United States.

The Mediterranean diet and health: a comprehensive overview

The Mediterranean diet (MedDiet), one of the most studied and well-known dietary patterns worldwide, has been associated with a wide range of benefits for health. In the present narrative review, we aimed to provide a comprehensive overview of the current knowledge on the relation of the MedDiet to important health outcomes, considering both observational and intervention studies with both risk factors and clinical diseases as outcomes. In addition, we considered the clinical and public health impacts of the MedDiet on both human and planetary health. Earlier research confirmed by recent studies has provided strong evidence for the benefits of the MedDiet on cardiovascular health, including reduction in the incidence of cardiovascular outcomes as well as risk factors including obesity, hypertension, metabolic syndrome, and dyslipidaemia. There is also evidence that MedDiet is associated with lower rates of incident diabetes, and better glycaemic control in diabetic patients compared to control diets. In prospective studies, adherence to the MedDiet reduced mortality, especially cardiovascular mortality, hence increased longevity. In addition, it has been associated with less age-related cognitive dysfunction and lower incidence of neurodegenerative disorders, particularly Alzheimer's disease. Furthermore, the relatively low environmental impacts (water, nitrogen and carbon footprint) of the MedDiet is an additional positive aspect of the Mediterranean dietary model. It is likely that the combination of a healthy diet with social behaviours and the way of life of Mediterranean regions makes the MedDiet a sustainable lifestyle model that could likely be followed in other regions with country-specific and culturally appropriate variations.

Association of bilateral oophorectomy and menopause hormone therapy with mild cognitive impairment: the REDLINC X study

BACKGROUND

Dementia is a major public health problem. Estrogen is a regulator of the central nervous system and its deficit could be involved in cognitive decline in older women.

OBJECTIVE

This study aimed to evaluate the association of bilateral oophorectomy, menopause hormone therapy (MHT) and other factors on mild cognitive impairment (MCI).

METHOD

The case-control study included 941 otherwise healthy postmenopausal women aged 60 years and over from six Latin American countries. Personal and family data were recorded and MCI was assessed using the Montreal Cognitive Assessment test (MoCA).

RESULTS

Average age, years of education and body mass index were 66.1 ± 5.8 years, 12.4 ± 5.0 years and 26.0 ± 4.3 kg/m², respectively. A total of 30.2% had undergone bilateral oophorectomy and 40.3% had used MHT. A total of 232 women (24.7%) had MCI. The prevalence of MCI was higher in women with intact ovaries and non-MHT users as compared to MHT users (29.3% vs. 11.7% [odds ratio (OR) 0.32; 95% confidence interval (CI) 0.20-0.51]). Among oophorectomized women, MCI prevalence was higher among non-MHT users as compared to MHT users (45.2% vs. 12.8% [OR 0.18; 95% CI 0.10-0.32]). Logistic regression analysis determined that the variables associated with MCI were age >65 years (OR 1.69; 95% CI 1.20-2.38), parity (having >2 children; OR 1.69; 95% CI 1.21-2.37), bilateral oophorectomy (OR 1.56; 95% CI 1.09-2.24), hypertension (OR 1.41; 95% CI 1.01-1.96), being sexually active (OR 0.56; 95% CI 0.40-0.79), education >12 years (OR 0.46; 95% CI 0.32-0.65) and MHT use (OR 0.31; 95% CI 0.21-0.46).

CONCLUSION

Age, parity, bilateral oophorectomy and hypertension are independent factors associated with MCI; contrary to this, higher educational level, maintaining sexual activity and using MHT are protective factors.

A Game a Day Keeps Cognitive Decline Away? A Systematic Review and Meta-Analysis of Commercially-Available Brain Training Programs in Healthy and Cognitively Impaired Older Adults

The rising prevalence rates of age-related cognitive impairment are a worldwide public concern, bringing about a surge in the number of "brain training" programs commercially available to the general public. Numerous companies advertise that their products improve memory and protect against cognitive decline, though researchers have voiced concerns regarding the validity of such claims. To address this issue, the current meta-analytic investigation examined evidence from 43 studies (encompassing 2,636 participants) to evaluate the efficacy of commercial training programs within two separate populations: healthy older adults and older adults with mild cognitive-impairment (MCI). Seven programs were identified: BrainGymmer, BrainHQ, CogMed, CogniFit, Dakim, Lumosity, and MyBrainTrainer. Analyses yielded small, significant near-transfer effects for both healthy and MCI samples. Far-transfer was not observed for the MCI sample, whereas a small, significant effect was found for subjective but not objective measures of far-transfer in the healthy sample. Analyses of individual domains (combining near-and far-transfer outcomes) yielded significant transfer to executive-functioning, memory, and processing-speed in healthy older adults. After adjusting for publication bias, only the effect size for processing speed remained significant. Transfer to attention, objective everyday functioning, fluid-intelligence, and visuospatial domains was not significant. Thus, whilst "brain training" may be suitable for enjoyment and entertainment purposes, there is currently insufficient empirical evidence to support that such training can improve memory, general cognition, or everyday functioning. This area of research is still in its infancy and warrants further investigation to provide more substantial evidence regarding the efficacy of this rapidly expanding industry.

The impact of exercise, sleep, and diet on neurocognitive recovery from mild traumatic brain injury in older adults: A narrative review

Mild traumatic brain injury (mTBI) accounts for a large majority of traumatic brain injuries sustained globally each year. Older adults, who are already susceptible to age-related declines to neurocognitive health, appear to be at an increased risk of both sustaining an mTBI and experiencing slower or impaired recovery. There is also growing evidence that mTBI is a potential risk factor for accelerated cognitive decline and neurodegeneration. Lifestyle-based interventions are gaining prominence as a cost-effective means of maintaining cognition and brain health with age. Consequently, inter-individual variations in exercise, sleep, and dietary patterns could influence the trajectory of post-mTBI neurocognitive recovery, particularly in older adults. This review synthesises the current animal and human literature centred on the mechanisms through which lifestyle-related habits and behaviours could influence acute and longer-term neurocognitive functioning following mTBI. Numerous neuroprotective processes which are impacted by lifestyle factors have been established in animal models of TBI. However, the literature is characterised by a lack of translation to human samples and limited appraisal of the interaction between ageing and brain injury. Further research is needed to better establish the therapeutic utility of applying lifestyle-based modifications to improve post-mTBI neurocognitive outcomes in older adults.

Mediterranean diet and risk for dementia and cognitive decline in a Mediterranean population

BACKGROUND

Current evidence suggests that nutrition in general and specific dietary patterns in particular, such as the Mediterranean type diet (MeDi), can be employed as potential preventive strategies against the development of dementia and cognitive decline. However, longitudinal data exploring the applicability of these findings in populations of Mediterranean origin are limited. The aim of the present study was to explore the potential relationships of MeDi adherence with dementia incidence rates and cognitive change over time in a traditional Mediterranean population, characterized by a lifelong exposure to Mediterranean eating habits and lifestyle.

METHODS

The sample consisted of 1046 non-demented individuals over the age of 64 (mean age = 73.1; SD = 5.0), with available baseline dietary information and longitudinal follow-up. Diagnosis of dementia was made by a full clinical and neuropsychological evaluation, while cognitive performance was assessed according to five cognitive domains (memory, language, attention-speed, executive functioning, visuospatial perception) and a global cognitive score. Adherence to MeDi was evaluated by an a priori score (range 0-55), derived from a detailed food frequency questionnaire.

RESULTS

A total of 62 incident dementia cases occurred during a mean (SD) of 3.1 (0.9) years of follow-up. Individuals in the highest MeDi quartile (highest adherence to MeDi) had a 72% lower risk for development of dementia, compared to those in the lowest one (p = 0.013). In addition, analysis of cognitive performance as a function of MeDi score revealed that the biennial cognitive benefit of a 10-unit increase in MeDi score offsets the cognitive decline associated with 1 year of cognitive aging.

CONCLUSION

In the present study, higher adherence to MeDi was associated with a reduced risk for dementia and cognitive decline in a traditional Mediterranean population.

Prevalence of mild cognitive impairment in surgical menopause: subtypes and associated factors

OBJECTIVE

The aim of this study was to determine the prevalence and associated factors of mild cognitive impairment (MCI) and subtypes, amnestic MCI (aMCI) and non-amnestic MCI (naMCI), in women with surgical menopause.

METHODS

We obtained the database containing information for 200 women with surgical menopause from our previous study. The Montreal Cognitive Assessment - total score, the Montreal Cognitive Assessment - memory index score (MoCA-MIS) and their age, years since menopause, education, medical and surgical history, hormone therapy use, exercise, sleep duration, alcohol use, smoking and family history of dementia were obtained. All participants without the MoCA-MIS were excluded.

RESULT

The average age of the 164 participants was 56.3 ± 6.9 years. The prevalence of MCI, aMCI and naMCI was 43.3%, 9.8% and 33.5%, respectively. The duration of education reduced MCI for 93% (95% confidence interval 0.03-0.20) of the women. In late postmenopause, hormone therapy >10 years showed 47% lower prevalence of MCI (age-adjusted odds ratio = 0.53, 95% confidence interval 0.22-1.28). Finally, length of education was the only independent factor associated with MCI and its subtypes.

CONCLUSION

We found a high prevalence of MCI and the non-amnestic subtype in women with surgical menopause. Further study is needed to clarify the long-term effects of surgical menopause on cognitive function.

Circulating B-vitamin biomarkers and B-vitamin supplement use in relation to quality of life in patients with colorectal cancer: results from the FOCUS consortium

BACKGROUND

B vitamins have been associated with the risk and progression of colorectal cancer (CRC), given their central roles in nucleotide synthesis and methylation, yet their association with quality of life in established CRC is unclear.

OBJECTIVES

To investigate whether quality of life 6 months postdiagnosis is associated with: 1) circulating concentrations of B vitamins and related biomarkers 6 months postdiagnosis; 2) changes in these concentrations between diagnosis and 6 months postdiagnosis; 3) B-vitamin supplement use 6 months postdiagnosis; and 4) changes in B-vitamin supplement use between diagnosis and 6 months postdiagnosis.

METHODS

We included 1676 newly diagnosed stage I-III CRC patients from 3 prospective European cohorts. Circulating concentrations of 9 biomarkers related to the B vitamins folate, riboflavin, vitamin B6, and cobalamin were measured at diagnosis and 6 months postdiagnosis. Information on dietary supplement use was collected at both time points. Health-related quality of life (global quality of life, functioning scales, and fatigue) was assessed by the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire 6 months postdiagnosis. Confounder-adjusted linear regression analyses were performed, adjusted for multiple testing.

RESULTS

Higher pyridoxal 5'-phosphate (PLP) was cross-sectionally associated with better physical, role, and social functioning, as well as reduced fatigue, 6 months postdiagnosis. Associations were observed for a doubling in the hydroxykynurenine ratio [3-hydroxykynurenine: (kynurenic acid + xanthurenic acid + 3-hydroxyanthranilic acid + anthranilic acid); an inverse marker of vitamin B6] and both reduced global quality of life (β = -3.62; 95% CI: -5.88, -1.36) and worse physical functioning (β = -5.01; 95% CI: -7.09, -2.94). Dose-response relations were observed for PLP and quality of life. No associations were observed for changes in biomarker concentrations between diagnosis and 6 months. Participants who stopped using B-vitamin supplements after diagnosis reported higher fatigue than nonusers.

CONCLUSIONS

Higher vitamin B6 status was associated with better quality of life, yet limited associations were observed for the use of B-vitamin supplements. Vitamin B6 needs further study to clarify its role in relation to quality of life.

Effect of surgical menopause and frontal lobe cognitive function

OBJECTIVE

This study aims to explore the prevalence of decreased frontal lobe function and its associated factors in women with surgical menopause.

METHODS

This study is a retrospective analysis of a cross-sectional study conducted between October 2013 and July 2014. Data from 164 women with surgical menopause were analyzed. The Montreal Cognitive Assessment Thai version (MoCA-T) test was administered by a psychologist. The MoCA frontal lobe function score was derived from visuospatial/executive, abstraction, attention, and verbal fluency tests. Multivariable logistic regression was used to assess data associated with decreased frontal lobe function.

RESULTS

The mean age of participants was 56.3 ± 6.9 years, and the mean time since menopause was 11.3 ± 7.4 years. The prevalence of decreased frontal lobe function score was 73.8%, with an average score of 6.21 ± 1.84. The independent factor associated with a lower MoCA frontal lobe function score was duration of education greater than 6 years.

CONCLUSION

Our study adds information about decreased frontal lobe function in almost three-quarters of women with surgical menopause. Duration of education greater than 6 years was a protective factor. Menopause hormone therapy usage did not seem to increase the detrimental effect on frontal lobe function when initiated in young women with surgical menopause.

The effects of phytoestrogens on postmenopausal health

Phytoestrogens are a group of non-steroidal polyphenolic plant-based substances, commonly used for the treatment of menopause-related conditions. They have both genomic and non-genomic effects, displaying weak affinity for estrogen receptors (ER) and preferentially binding to ER-B over ER-A. However, evidence for the benefits of phytoestrogen consumption has been limited. We conducted a review of recent literature, focusing on systematic reviews and meta-analyses reporting on postreproductive health effects of phytoestrogens. While many trials concerning dietary and supplementary phytoestrogens have been conducted, evidence of clinical efficacy is heterogeneous and inconclusive. There appears to be reduction in the vasomotor symptoms of menopause with phytoestrogen intake; however, it is likely small and slow in onset. Phytoestrogens also appear to improve bone mineral density and markers of cardiovascular risk; however, there is inadequate research regarding long-term outcomes. There appear to be no harmful effects of phytoestrogens on breast, endometrial cancer or colorectal cancer and phytoestrogens intake may in fact be protective. Research regarding the effect of phytoestrogens on cognition is mixed, with most studies reporting no significant association. Overall, individual variations in the metabolism of phytoestrogens and age-related genomic effects may account for the considerable variability in the measured effects of phytoestrogens.

Interaction between physical exercise and APOE gene polymorphism on cognitive function in older people

We aimed to present an overview of the literature regarding the interaction between physical exercise and APOE gene polymorphism on cognitive function, particularly in patients with Alzheimer's disease (AD). Firstly, this review focused on the effect of the physical exercise on cognitive function, regardless of APOE gene polymorphism. Some studies have shown that a high level of cardiorespiratory fitness is associated with less neuronal damage with an improvement in memory score tests whereas other studies failed to detect any association between physical exercise and cognitive improvement either in healthy individuals or patients with AD. Taken together, standardized protocols and more longitudinal studies are required to provide a better insight into the effects of physical exercise on cognitive function. Although there is no agreement in the literature regarding the effects of physical exercise on cognitive function, it is well established that it improves social interaction and the feeling of well-being, thereby positively contributing to the quality of life of the elderly. Regarding the influence of physical exercise on cognitive function in APOE ε4 allele carriers, the data trend shows that the carriers of allele ε4 for APOE gene were more responsive to the beneficial effects of physical exercise on cognitive function compared with non-carriers. Nevertheless, studies with larger sample sizes will provide more accuracy about this relationship.

Cognitive Training as a Potential Activator of Hippocampal Neurogenesis in the Rat Model of Sporadic Alzheimer's Disease

There is a growing body of evidence that interventions like cognitive training or exercises prior to the manifestation of Alzheimer’s disease (AD) symptoms may decelerate cognitive decline. Nonetheless, evidence of prevention or a delay of dementia is still insufficient. Using OXYS rats as a suitable model of sporadic AD and Wistar rats as a control, we examined effects of cognitive training in the Morris water maze on neurogenesis in the dentate gyrus in presymptomatic (young rats) and symptomatic (adult rats) periods of development of AD signs. Four weeks after the cognitive training, we immunohistochemically estimated densities of quiescent and amplifying neuronal progenitors, neuronal-lineage cells (neuroblasts and immature and mature neurons), and astrocytes in young and adult rats, and the amyloid precursor protein and amyloid-β in adult rats. Reference memory was defective in OXYS rats. The cognitive training did not affect neuronal-lineage cells’ density in either rat strain either at the young or adult age, but activated neuronal progenitors in young rats and increased astrocyte density and downregulated amyloid-β in adult OXYS rats. Thus, to activate adult neurogenesis, cognitive training should be started before first neurodegenerative changes, whereas cognitive training accompanying amyloid-β accumulation affects only astrocytic support.

Anti-aging effects of Ribes meyeri anthocyanins on neural stem cells and aging mice

Aging is associated with neurological impairment and cognitive decline. Flavonoids are very promising in anti-aging research in mouse models. Ribes meyeri anthocyanins are rich in abundant flavonoids, but their anti-aging biological activities remain unknown. In this study, we prepared an R. meyeri anthocyanin extract and analyzed its effects on neural stem cell (NSC) senescence in vivo and in vitro. We isolated mouse NSCs and used cell counting kit-8 (CCK-8), cell cycle, reactive oxygen species (ROS), and immunofluorescence methods to analyze the anti-aging effects of R. meyeri anthocyanins as well as naringenin (Nar), which metabolic analysis revealed as an important flavonoid in R. meyeri anthocyanins. RNA-sequencing (RNA-seq) and enzyme-linked immuno sorbent assay (ELISA) methods were also used to investigate Nar-specific mechanisms of anti-aging. After R. meyeri anthocyanin treatment, NSC proliferation accelerated, and NSCs had decreased senescence markers, and reduced P16^ink4a expression. R. meyeri anthocyanin treatment also reversed age-dependent neuronal loss in vivo and in vitro. Nar blocked mNSC aging in vitro and improved spatial memory and cognitive abilities in aging mice through downregulation of plasma TNF-α protein. These findings suggest that R. meyeri anthocyanins increase NSC proliferation and improve neurogenesis with aging via Nar-induced reductions in TNF-α protein levels in vivo.

A scoping review of network meta-analyses assessing the efficacy and safety of complementary and alternative medicine interventions

BACKGROUND

Network meta-analysis (NMA) has rapidly grown in use during the past decade for the comparison of healthcare interventions. While its general use in the comparison of conventional medicines has been studied previously, to our awareness, its use to assess complementary and alternative medicines (CAM) has not been studied. A scoping review of the literature was performed to identify systematic reviews incorporating NMAs involving one or more CAM interventions.

METHODS

An information specialist executed a multi-database search (e.g., MEDLINE, Embase, Cochrane), and two reviewers performed study selection and data collection. Information on publication characteristics, diseases studied, interventions compared, reporting transparency, outcomes assessed, and other parameters were extracted from each review.

RESULTS

A total of 89 SR/NMAs were included. The largest number of NMAs was conducted in China (39.3%), followed by the United Kingdom (12.4%) and the United States (9.0%). Reviews were published between 2010 and 2018, with the majority published between 2015 and 2018. More than 90 different CAM therapies appeared at least once, and the median number per NMA was 2 (IQR 1-4); 20.2% of reviews consisted of only CAM therapies. Dietary supplements (51.1%) and vitamins and minerals (42.2%) were the most commonly studied therapies, followed by electrical stimulation (31.1%), herbal medicines (24.4%), and acupuncture and related treatments (22.2%). A diverse set of conditions was identified, the most common being various forms of cancer (11.1%), osteoarthritis of the hip/knee (7.8%), and depression (5.9%). Most reviews adequately addressed a majority of the PRISMA NMA extension items; however, there were limitations in indication of an existing review protocol, exploration of network geometry, and exploration of risk of bias across studies, such as publication bias.

CONCLUSION

The use of NMA to assess the effectiveness of CAM interventions is growing rapidly. Efforts to identify priority topics for future CAM-related NMAs and to enhance methods for CAM comparisons with conventional medicine are needed. SYSTEMATIC REVIEW REGISTRATION: https://ruor.uottawa.ca/handle/10393/35658.

Psychobiological indicators of the subjectively experienced health status - findings from the Women 40+ Healthy Aging Study

BACKGROUND

Healthy aging is particularly important in women, as their life-span is generally longer than men's, leaving women at higher risk for age-related diseases. Understanding determinants of women's healthy aging is therefore a major public health interest. Clinical utility of previous research is limited, through its focus on either single psychosocial or biological predictors. The present study investigated psychobiological predictors of women's healthy aging, for the first time including positive psychological traits and biomarkers of healthy aging.

METHODS

Totally, 121 generally healthy women aged 40 to 75 were investigated cross-sectionally. Healthy aging was operationalized via self-rated health (SRH). To gain a nuanced view of the particularities at the upper end of the illness-wellness continuum, women with excellent SRH and those with good SRH were analyzed as distinct groups. Socioeconomic and sociodemographic variables, health behavior, resilience, optimism, and self-worth as well as menopausal symptoms, and levels of steroid hormones and gonadotropins were considered as predictors of SRH. Binary logistic regression analyses using the forward conditional method were performed with the two health status groups as dependent variable.

RESULTS

Women with a lower body mass index (BMI; OR = .59, 95% CI = .33-1.03), higher intensive physical activity (OR = 2.27, 95% CI = 1.06-4.86), and higher resilience (OR = 2.37, 95% CI = 1.34-4.18) were more likely to rate their health as excellent compared to good. No clinically significant differences could be found regarding endocrine levels.

CONCLUSION

Psychobiological indicators (lower BMI, intensive physical activity, higher resilience) discriminated SRH at the top level of the health spectrum. In healthy women, the predictive value of endocrine markers seems to be secondary. Interventions targeting these indicators could promote women's healthy aging.

Association Between Subjective Cognitive Decline and Social and Emotional Support in US Adults

Subjective cognitive decline (SCD) has been linked to Alzheimer's Disease in the literature. However, little is known about whether SCD is associated with social/emotional support (SES). To investigate this association, this study utilized the 2015 and 2016 Behavioral Risk Factor Surveillance System data. A study population of 17206 participants aged 45 years and older who responded to both the Emotional Support and Life Satisfaction survey module and the Cognition Decline survey module were included. Of this study population, 11.22% had SCD, and 21.83% reported insufficient SES. A much higher percentage of those with insufficient SES experienced SCD compared to those with sufficient SES (21.15% vs 8.45%, P < .0001). Insufficient SES was significantly associated with SCD (odds ratio = 1.68, 95% confidence interval: 1.37-2.06), after controlling for other factors. Furthermore, this study found certain demographic groups such as female, white, or married groups were more likely to receive sufficient SES.

Pathways of Prevention: A Scoping Review of Dietary and Exercise Interventions for Neurocognition

Alzheimer's disease and related dementias (ADRD) represent an increasingly urgent public health concern, with an increasing number of baby boomers now at risk. Due to a lack of efficacious therapies among symptomatic older adults, an increasing emphasis has been placed on preventive measures that can curb or even prevent ADRD development among middle-aged adults. Lifestyle modification using aerobic exercise and dietary modification represents one of the primary treatment modalities used to mitigate ADRD risk, with an increasing number of trials demonstrating that exercise and dietary change, individually and together, improve neurocognitive performance among middle-aged and older adults. Despite several optimistic findings, examination of treatment changes across lifestyle interventions reveals a variable pattern of improvements, with large individual differences across trials. The present review attempts to synthesize available literature linking lifestyle modification to neurocognitive changes, outline putative mechanisms of treatment improvement, and discuss discrepant trial findings. In addition, previous mechanistic assumptions linking lifestyle to neurocognition are discussed, with a focus on potential solutions to improve our understanding of individual neurocognitive differences in response to lifestyle modification. Specific recommendations include integration of contemporary causal inference approaches for analyzing parallel mechanistic pathways and treatment-exposure interactions. Methodological recommendations include trial multiphase optimization strategy (MOST) design approaches that leverage individual differences for improved treatment outcomes.

The Mediterranean, Dietary Approaches to Stop Hypertension (DASH), and Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) Diets Are Associated with Less Cognitive Decline and a Lower Risk of Alzheimer's Disease-A Review

As there is currently no cure for dementia, there is an urgent need for preventive strategies. The current review provides an overview of the existing evidence examining the associations of the Mediterranean, Dietary Approaches to Stop Hypertension (DASH), and Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diets and their dietary components with cognitive decline, dementia, and Alzheimer's disease (AD). A systematic search was conducted within Ovid Medline for studies published up to 27 March 2019 and reference lists from existing reviews and select articles were examined to supplement the electronic search results. In total, 56 articles were included. Higher adherence to the Mediterranean diet was associated with better cognitive scores in 9 of 12 cross-sectional studies, 17 of 25 longitudinal studies, and 1 of 3 trials. Higher adherence to the DASH diet was associated with better cognitive function in 1 cross-sectional study, 2 of 5 longitudinal studies, and 1 trial. Higher adherence to the MIND diet was associated with better cognitive scores in 1 cross-sectional study and 2 of 3 longitudinal studies. Evidence on the association of these dietary patterns with dementia in general was limited. However, higher adherence to the Mediterranean diet was associated with a lower risk of AD in 1 case-control study and 6 of 8 longitudinal studies. Moreover, higher adherence to the DASH or MIND diets was associated with a lower AD risk in 1 longitudinal study. With respect to the components of these dietary patterns, olive oil may be associated with less cognitive decline. In conclusion, current scientific evidence suggests that higher adherence to the Mediterranean, DASH, or MIND diets is associated with less cognitive decline and a lower risk of AD, where the strongest associations are observed for the MIND diet.

Medical management, prevention and mitigation of environmental risks factors in Neurology

The human environment and exposures arising therefrom are major contributors to neurological disorders ranging from stroke to neurodegenerative diseases. Reduction of exposure to environmental risk factors, with the goal of disease prevention or control, is addressed at the individual as well as the societal level and in recognition of differential subject vulnerability. We examine some practical solutions in high-income countries that may allow a better adaptation to environmental risks and reduce their adverse impact on the nervous system. We consider the citizen's role in reducing unhealthy exposures and explore new approaches to treatment.

Perspective: Network Meta-analysis Reaches Nutrition Research: Current Status, Scientific Concepts, and Future Directions

Traditional pairwise meta-analysis (PMA) is a very useful method that pools evidence from one study design type if appropriate; its widespread use in nutrition research is an important phenomenon. Recently, a promising method for more advanced evidence-synthesis, called network meta-analysis (NMA), was introduced. NMA is an extension of PMA that enables simultaneous comparison of multiple interventions. NMA combines direct evidence (i.e., trials comparing 2 interventions directly) and indirect evidence (i.e., from a connected route via ≥1 comparators, e.g. placebo) in a network of studies. NMAs have the potential to advance knowledge in the field of nutrition as they provide insights that cannot be obtained by individual 2-arm randomized controlled trials or PMA. Thus, in this perspective paper, we aim to summarize the current (methodologic) status of published NMAs in nutrition research and emphasize advances and strengths in comparison with traditional PMA through specific examples, and highlight potential pitfalls and limitations. NMA is an emerging methodology in the field of nutrition research. A PubMed search identified only 23 nutrition research-related NMAs published since the inception of journals up to January 8, 2019 (61% of them published since 2017), compared with >5000 published PMAs. Moreover, we aim to highlight the scientific concepts and standards through the use of the following NMA example: "Which type of oils/solid fats offers the greatest impact on blood lipids?" In this regard, we discuss intervention definitions, transitivity/similarity, statistical methods, description and visualization of results, inconsistency, ranking, dissemination bias, assessing the certainty of evidence by Grading of Recommendations Assessment, Development and Evaluation, and reporting guidelines. We expect that rigorously conducted NMAs based on high-quality systematic reviews will become the new evidence synthesis benchmark in nutrition research. However, caution is warranted because abuse and misinterpretations of PMA and NMA findings could hamper the scientific field and possibly decision-making regarding public policy.

Steroid secretion in healthy aging

Nowadays, people spend a considerable amount of their lives as older adults, but this longer lifespan is often accompanied by an increase in chronic conditions and disease, resulting in reduced quality of life and unprecedented societal and economic burden. Healthy aging is therefore increasingly recognized as a healthcare priority. Physical and mental adaptations to changes over the life course, and the maintenance of well-being, represent pivotal challenges in healthy aging. To capture the complexity of healthy aging, we propose a specific phenotype based on body composition, cognition, mood, and sexual function as indicators of different dimensions of healthy aging. With increasing age, sex hormones as well as glucocorticoids undergo significant alterations, and different patterns emerge for women and men. This review describes age-related patterns of change for women and men, and sheds light on the underlying mechanisms. Furthermore, an overview is provided of the challenges for healthy aging resulting from these age-related steroid alterations. While clinical practice guidelines recommend hormonal treatment only in the case of consistently low hormone levels and symptoms of hormone deficiency, physical exercise and a healthy lifestyle emerge as preventive strategies which can counter age-related hormonal changes and at best prevent chronic conditions.

Neurocognition in treatment-resistant hypertension: profile and associations with cardiovascular biomarkers

BACKGROUND

Hypertension in midlife has been associated with increased risk of stroke and neurocognitive decline. Few studies, however, have examined neurocognition among individuals with treatment-resistant hypertension or potential mechanisms by which treatment-resistant hypertension may impair neurocognition.

METHODS

We examined the pattern of neurocognitive impairment and potential mechanisms in a sample of 96 overweight adults with treatment-resistant hypertension, aged 41-81 years. Neurocognitive function was assessed using a 45-min test battery consisting of executive function and memory. Vascular and metabolic mechanisms examined included cerebrovascular risk factors (CVRFs: Framingham Stroke Risk Profile), insulin sensitivity (homeostatic model assessment of insulin resistance), waist-to-hip ratio, microvascular function (hyperemic response), and peak oxygen consumption from an exercise treadmill test. Simple path analyses were used to assess the association between potential vascular and metabolic mechanisms and neurocognition.

RESULTS

Neurocognitive impairments were common, with 70% of the sample exhibiting impaired performance on at least one executive function subtest and 38% on at least one measure of memory. Higher levels of aerobic fitness, greater insulin sensitivity, and better microvascular function, as well as lower CVRFs and waist-to-hip ratio were associated with better neurocognition. In path analyses, aerobic fitness, microvascular function, and CVRFs all were independently associated with neurocognitive performance. Insulin resistance associated with worse executive function but better memory performance among older participants.

CONCLUSION

Neurocognitive impairments are common in adults with treatment-resistant hypertension, particularly on tests of executive function. Better neurocognition is independently associated with aerobic fitness, microvascular function, and CVRFs.

Effects of Mind-Body Exercises on Cognitive Function in Older Adults: A Meta-Analysis

BACKGROUND/OBJECTIVES

Mind-body exercise has positive effects on cognitive performance, according to clinical observation and experts' recommendations. However, its potential benefits for the cognitive function of aging adults are uncertain and still lack systematic estimations. Therefore, we conducted a systematic review and meta-analysis to evaluate the overall efficacy and effectiveness of mind-body exercises for cognitive performance in aging individuals with or without cognitive impairment.

DESIGN

A systematic review and meta-analysis.

SETTING AND PARTICIPANTS

We searched related trials through June 2018 from four databases: Medline, Embase, PsycINFO (all via Ovid), and the Cochrane Library/Central Register of Controlled Trials.

MEASUREMENTS

Methodological quality was assessed using the Cochrane Risk of Bias Tool. A meta-analysis of comparative effects was performed using Review Manager v.5.3 software, and publication bias was examined using Egger's test.

RESULTS

A total of 32 randomized controlled trials with 3624 participants were ultimately included in this meta-analysis. The results revealed that mind-body exercises as a whole had benefits in improving global cognition compared with that of the control group (mean difference [MD] = 0.92; 95% confidence interval [CI] = 0.33-1.51; p = .002) and were more effective than control interventions in promoting cognitive flexibility (MD = -8.80; 95% CI = -15.22 to -2.38; p = .007), working memory (MD = 0.32; 95% CI = 0.01-0.64; p = .05), verbal fluency (standardized mean difference [SMD] = 0.27; 95% CI = 0.09-0.45; p = .003), and learning (SMD = 0.24; 95% CI = 0.10-0.39; p = .001) on cognitively intact or impaired older adults. In dose-subgroup analysis, only moderate exercise intensity (60-120 min per week) significantly increased global cognition scores compared with those of the control group (MD = 1.15; 95% CI = 0.34-1.97; p = .006).

CONCLUSION

Mind-body exercises, especially tai chi and dance mind-body exercise, are beneficial for improving global cognition, cognitive flexibility, working memory, verbal fluency, and learning in cognitively intact or impaired older adults. Moderate intensity is recommended as the optimal dose for older adults. J Am Geriatr Soc 67:749-758, 2019.

Unsaturated Fatty Acid Intakes During Midlife Are Positively Associated with Later Cognitive Function in Older Adults with Modulating Effects of Antioxidant Supplementation

Background

Given the drastic demographic changes characterized as "population aging," the disease burden related to dementia is a major public health problem. The scientific literature documenting the link between mono- and polyunsaturated fatty acids (MUFAs, PUFAs) and cognitive function during aging is plentiful, but findings are inconsistent.

Objectives

We aimed to evaluate the association between intakes of unsaturated fatty acids at midlife and cognitive performance 13 y later in French adults, and to test for a modulating effect of antioxidant supplementation.

Methods

Fatty acid intakes were estimated with the use of repeated 24-h records (1994-1996) among 3362 subjects (mean ± SD age: 65.5 ± 4.6 y) of the SU.VI.MAX (Supplementation with Antioxidant Vitamins and Minerals) study, including an intervention phase (1994-2002) during which participants were randomly assigned to an "antioxidant supplementation" or placebo group. Cognitive performance was assessed at follow-up only (in 2007-2009) via a battery of 6 standardized neuropsychological tests. A global cognitive score was calculated as the sum of T-scores of the 6 tests. Multivariable-adjusted regression analyses were performed to provide regression coefficients and 95% CIs.

Results

In multivariable models, total MUFAs, total PUFAs, and n-6 PUFAs (ω-6 PUFAs) were positively associated with overall cognitive functioning. n-3 PUFA (ω-3 PUFA) intakes showed positive associations among supplemented participants only (mean difference Tertile3 versus Tertile1: 1.40; 95% CI: 0.30, 2.51; P-trend = 0.01, P-interaction = 0.01). A detrimental role of arachidonic acid for cognitive functioning was only detected in the placebo group (mean difference Tertile3 versus Tertile1: -1.38; 95% CI: -2.57, -0.18; P-trend = 0.02, P-interaction = 0.07).

Conclusion

Whereas higher total MUFA and n-6 PUFA intakes may be generally beneficial for maintaining cognitive health during aging, a higher consumption of n-3 fatty acids may only be beneficial among individuals with an adequate antioxidant status. These findings underline the importance of not only focusing on specific nutrients for dementia prevention, but also considering the complex interaction between consumed nutrients. This trial was registered at clinicaltrials.gov as NCT00272428.

Microvascular Endothelial Function and Neurocognition Among Adults With Major Depressive Disorder

BACKGROUND

Cardiovascular risk factors (CVRFs) and endothelial dysfunction have been associated independently with poorer neurocognition in middle-aged adults, particularly on tests of frontal lobe function. However, to our knowledge, no studies have examined markers of microvascular dysfunction on neurocognition or the potential interaction between macro- and microvascular biomarkers on neurocognition in middle-aged and older adults with major depressive disorder (MDD).

METHODS

Participants included 202 adults with MDD who were not receiving mental health treatment. Microvascular endothelial function was assessed using a noninvasive marker of forearm reactive hyperemia velocity while macrovascular endothelial function was assessed using flow-mediated dilation (FMD) of the brachial artery. CVRFs were assessed using the Framingham Stroke Risk Profile and fasting lipid levels. A standardized neurocognitive assessment battery was used to assess three cognitive domains: executive function, working memory, and verbal memory.

RESULTS

Greater microvascular dysfunction was associated with poorer neurocognition across all three domains. Microvascular function continued to predict verbal memory performance after accounting for background factors and CVRFs. Macro- and microvascular function interacted to predict working memory performance (F = 4.51_{1, 178}, p = 0.035), with a similar nonsignificant association for executive function (F = 2.73_{1, 178}, p = 0.095), with moderate associations observed between microvascular function and neurocognition in the presence of preserved FMD (r₆₁ = 0.40, p = 0.001), but not when FMD was impaired (r₆₃ = -0.05, p = 0.675).

CONCLUSION

Greater microvascular dysfunction is associated with poorer neurocognition among middle-aged and older adults. This association was strongest in participants with preserved macrovascular function.

Self-reported cognitive function in a large international cohort of people with multiple sclerosis: associations with lifestyle and other factors

Background and purpose

We aimed to estimate the prevalence of perceived cognitive impairment (PCI) and explore its associations with lifestyle and disease characteristics in a large international cohort of people with multiple sclerosis (MS).

Methods

This study was a cross‐sectional analysis. Participants rated their cognitive function over the preceding 4 weeks using four questions in a subscale within the Multiple Sclerosis Quality of Life questionnaire (MSQOL‐54). These questions assessed perceived concentration, attention and memory by the patient and family/friends. Four definitions of PCI were derived, ranging from lowest to highest specificity. Associations with PCI were assessed by log‐binomial regression.

Results

The prevalence of PCI in our sample ranged from 41.0% (95% confidence interval, 39.0–43.0) using the least‐specific definition to 11.6% (95% confidence interval, 10.3–12.9) using the most specific definition. A number of factors were associated with PCI, increasing in magnitude as the definition specificity increased, including positive associations for smoking and body mass index, whereas physical activity, dietary quality and use of vitamin D/omega‐3 supplements were inversely associated with PCI.

Conclusions

Our study reports associations between healthy lifestyle behaviours and PCI in people with MS. Although reverse causality is a potential explanation for our findings, previous studies have shown comparable associations with healthy lifestyle and MS onset and progression. Subject to external validation, these results suggest benefits realized from a healthy lifestyle in people with MS.

The effects of aging on auditory cortical function

Age-related hearing loss is a prominent deficit, afflicting approximately half of the geriatric population. In many cases, the person may have no deficits in detecting sounds, but nonetheless suffers from a reduced ability to understand speech, particularly in a noisy environment. While rodent models have shown that there are a variety of age-related changes throughout the auditory neuraxis, far fewer studies have investigated the effects at the cortical level. Here I review recent evidence from a non-human primate model of age-related hearing loss at the level of the core (primary auditory cortex, A1) and belt (caudolateral field, CL) in young and aged animals with normal detection thresholds. The findings are that there is an increase in both the spontaneous and driven activity, an increase in spatial tuning, and a reduction in the temporal fidelity of the response in aged animals. These results are consistent with an age-related imbalance of excitation and inhibition in the auditory cortex. These spatial and temporal processing deficits could underlie the major complaint of geriatrics, that it is difficult to understand speech in noise.

Quality assessment of systematic reviews of vitamin D, cognition and dementia

BACKGROUND

There is conflicting evidence regarding the association of vitamin D with cognition performance and dementia.AimsWe aimed to summarise the evidence on the association of vitamin D with cognitive performance, dementia and Alzheimer disease through a qualitative assessment of available systematic reviews and meta-analyses.

METHOD

We conducted an overview of the systematic reviews of all study types with or without meta-analyses on vitamin D and either Alzheimer disease, dementia or cognitive performance up to June 2017.

RESULTS

Eleven systematic reviews were identified, nine of which were meta-analyses with substantial heterogeneity, differing statistical methods, variable methodological quality and quality of data abstraction. A Measurement Tool to Assess Systematic Reviews checklist scores ranged from 4 to 10 out of 11, with seven reviews of 'moderate' and four of 'high' methodological quality. Out of six meta-analyses on the association between low serum concentration of 25-hydroxyvitamin D and risk of dementia, five showed a positive association. Results of meta-analyses on the association between low serum concentration of 25-hydroxyvitamin D and memory function tests showed conflicting results.

CONCLUSIONS

This systematic evaluation of available systematic reviews provided a clearer understanding of the potential link between low serum vitamin D concentrations and dementia. This evaluation also showed that the quality of the available evidence is not optimal because of both the low methodological quality of the reviews and low quality of the original studies. Interpretation of these systematic reviews should therefore be made with care.Declaration of interestNone.

Enhancing memory self-efficacy during menopause through a group memory strategies program

OBJECTIVE

Anxiety about memory during menopause can affect quality of life. We aimed to improve memory self-efficacy during menopause using a group memory strategies program.

METHODS

The program was run five times for a total of 32 peri- and postmenopausal women, age between 47 and 60 years, recruited from hospital menopause and gynecology clinics. The 4-week intervention consisted of weekly 2-hour sessions, and covered how memory works, memory changes related to ageing, health and lifestyle factors, and specific memory strategies. Memory contentment (CT), reported frequency of forgetting (FF), use of memory strategies, psychological distress, and attitude toward menopause were measured. A double-baseline design was applied, with outcomes measured on two baseline occasions (1-month prior [T1] and in the first session [T2]), immediately postintervention (T3), and 3-month postintervention (T4). To describe changes in each variable between time points paired sample t tests were conducted. Mixed-effects models comparing the means of random slopes from T2 to T3 with those from T1 to T2 were conducted for each variable to test for treatment effects.

RESULTS

Examination of the naturalistic changes in outcome measures from T1 to T2 revealed no significant changes (all Ps > 0.05). CT, reported FF, and use of memory strategies improved significantly more from T2 to T3, than from T1 to T2 (all Ps < 0.05). Neither attitude toward menopause nor psychological distress improved significantly more postintervention than during the double-baseline (all Ps > 0.05). Improvements in reported CT and FF were maintained after 3 months.

CONCLUSIONS

The use of group interventions to improve memory self-efficacy during menopause warrants continued evaluation.

Cognition and the menopause transition

Complaints about forgetfulness, "brain fog," and difficulty concentrating are common in women transitioning through menopause. Women with these cognitive complaints often express concern about whether these problems are normal, related to menopause, or represent a symptom of Alzheimer disease or another serious cognitive disorder. In this Practice Pearl, we provide a brief summary of the scientific literature on the frequency of cognitive complaints in midlife women, the validity of complaints in relation to performance on standardized cognitive tests, and the influence of menopause on cognitive performance. We then offer recommendations for healthcare providers and women to address cognitive concerns.