Body mass index, lifestyles, physical performance and cognitive decline: the "Treviso Longeva (TRELONG)" study

Dietary Patterns and Alzheimer's Disease: An Updated Review Linking Nutrition to Neuroscience

Alzheimer's disease (AD) is a growing concern for the aging population worldwide. With no current cure or reliable treatments available for AD, prevention is an important and growing area of research. A range of lifestyle and dietary patterns have been studied to identify the most effective preventive lifestyle changes against AD and related dementia (ADRD) pathology. Of these, the most studied dietary patterns are the Mediterranean, DASH, MIND, ketogenic, and modified Mediterranean-ketogenic diets. However, there are discrepancies in the reported benefits among studies examining these dietary patterns. We herein compile a narrative/literature review of existing clinical evidence on the association of these patterns with ADRD symptomology and contemplate their preventive/ameliorative effects on ADRD neuropathology in various clinical milieus. By and large, plant-based dietary patterns have been found to be relatively consistently and positively correlated with preventing and reducing the odds of ADRD. These impacts stem not only from the direct impact of specific dietary components within these patterns on the brain but also from indirect effects through decreasing the deleterious effects of ADRD risk factors, such as diabetes, obesity, and cardiovascular diseases. Importantly, other psychosocial factors influence dietary intake, such as the social connection, which may directly influence diet and lifestyle, thereby also impacting ADRD risk. To this end, prospective research on ADRD should include a holistic approach, including psychosocial considerations.

Extended-release metformin improves cognitive impairment in frail older women with hypertension and diabetes: preliminary results from the LEOPARDESS Study

BACKGROUND

Women have a high risk of frailty independently of age and menopause state. Diabetes and hypertension increase the risk of frailty and cognitive impairment. Metformin has been employed in post-menopausal women and some reports have shown encouraging effects in terms of attenuated frailty. However, the impact on cognitive performance of a recently introduced extended-release formulation of metformin has never been explored.

METHODS

We studied consecutive frail hypertensive and diabetic older women presenting at the ASL (local health authority of the Italian Ministry of Health) Avellino, Italy, from June 2021 to August 2022, who were treated or not with extended-release metformin. We included a control group of frail older males with diabetes and hypertension treated with extended-release metformin and a control group of frail older women with diabetes and hypertension treated with regular metformin.

RESULTS

A total of 145 patients successfully completed the study. At the end of the 6-month follow-up, we observed a significantly different cognitive performance compared to baseline in the group of frail women treated with extended-release metformin (p: 0.007). Then, we compared the follow-up groups and we observed significant differences between frail women treated vs. untreated (p: 0.041), between treated frail women and treated frail men (p: 0.016), and between women treated with extended-release metformin vs. women treated with regular metformin (p: 0.048). We confirmed the crucial role of extended-release metformin applying a multivariable logistic analysis to adjust for potential confounders.

CONCLUSIONS

We evidenced, for the first time to the best of our knowledge, the favorable effects on cognitive impairment of extended-release metformin in frail women with diabetes and hypertension.

Does the frequency of reading and writing habits contribute to executive functions, intelligence, and learning in adolescents with healthy development?

The influence of the frequency of reading and writing habits (FRWH) on cognition has been investigated by several studies in the literature. However, the implications of FRWH on executive development, intelligence, and academic achievement are not yet clear in adolescents with healthy development. The aim was to verify whether there are differences in executive functions, intelligence, and academic achievement between adolescents with high and low FRWH. Moreover, we aimed to investigate if there are differences in the parental FRWH between adolescents with high and low FRWH. The sample was composed of 47 healthy adolescents, n = 24 with high FRWH and n = 23 with low FRWH. Adolescents with higher FRWH had better performance on measures of vocabulary, Speech Act analysis, and Oral Narrative Discourse. Therefore, a high FRWH has a positive influence on the cognitive development of healthy adolescents, especially with regard to pragmatic language. However, adolescents with low FRWH performed better than those with a high FRWH on an automatic counting task. The interpretation of cognitive performance and academic achievement scores in neuropsychological assessment should consider the FRWH of parents and adolescents. This factor should be targeted by early stimulation interventions to help adolescents achieve the highest possible levels of global development.

Recent Updates on Associations among Various Obesity Metrics and Cognitive Impairment: from Body Mass Index to Sarcopenic Obesity

Obesity and obesity-associated morbidity continues to be a major public health issue worldwide. Dementia is also a major health concern in aging societies and its prevalence has increased rapidly. Many epidemiologic studies have shown an association between obesity and cognitive impairment, but this relationship is not as well established as other comorbidities. Conflicting results related to the age and sex of participants, and the methodology used to define obesity and dementia may account for the uncertainty in whether obesity is a modifiable risk factor for dementia. More recently, sarcopenia and sarcopenic obesity have been reported to be associated with cognitive impairment. In addition, new mediators such as the muscle-myokine-brain axis and gut-microbiota-brain axis have been suggested and are attracting interest. In this review, we summarize recent evidence on the link between obesity and cognitive impairment, especially dementia. In particular, we focus on various metrics of obesity, from body mass index to sarcopenia and sarcopenic obesity.

Adherence to High Dietary Diversity and Incident Cognitive Impairment for the Oldest-Old: A Community-Based, Nationwide Cohort Study

BACKGROUND AND AIMS

Dietary diversity change is associated with cognitive function, however, whether the effect still exists among the oldest-old (80+) is unclear. Our aim was to examine the effect of dietary diversity changes on cognitive impairment for the oldest-old in a large prospective cohort.

METHODS

Within the Chinese Longitudinal Healthy Longevity Study, 6237 adults older than 80 years were included. The dietary diversity score (DDS) was assessed by a simplified food frequency questionnaire (FFQ). Cognitive impairment was defined as a Mini-Mental State Examination (MMSE) score lower than 18 points. Cognitive decline was defined as a reduction of total MMSE score ≥3 points, and cognitive decline of different subdomains was defined as a reduction of ≥15% in the corresponding cognitive domain. The multivariate-adjusted Cox proportional hazard model evaluated the effects of DDS change on cognitive decline. The linear mixed-effect model was used to test subsequent changes in MMSE over the years.

RESULTS

During 32,813 person-years of follow-up, 1829 participants developed cognitive impairment. Relative to the high-high DDS change pattern, participants in the low-low and high-low patterns were associated with an increased risk of cognitive impairment with a hazard ratio (95% confidential interval, CI) of 1.43 (1.25, 1.63) and 1.44 (1.24, 1.67), and a faster decline in the MMSE score over the follow-up year. Participants with the low-high pattern had a similar incidence of cognitive impairment with HRs (95% CI) of 1.03 (0.88, 1.20). Compared with the stable DDS status group (-1-1), the risk of cognitive impairment was higher for those with large declines in DDS (≤-5) and the HR was 1.70 (95% CI: 1.44, 2.01).

CONCLUSIONS

Even for people older than 80, dietary diversity change is a simple method to identify those who had a high risk of cognitive decline. Keeping high dietary diversity is beneficial for cognitive function and its subdomain even in the final phase of life, especially for females and the illiterate oldest-old.

Association between the mediterranean diet and cognitive health among healthy adults: A systematic review and meta-analysis

Background

An increasing prevalence of cognitive disorders warrants comprehensive systematic reviews on the effect of diet on cognitive health. Studies have suggested that the Mediterranean (MeDi) diet has protective effects against metabolic diseases. However, comprehensive systematic reviews on the effect of the MeDi diet on the cognitive decline are limited. We investigated whether adherence to the MeDi diet could lower the risk of the cognitive disorder or improve cognitive function in older adults.

Methods

In this systematic review and meta-analysis, PubMed, Web of Science, PsycINFO, Scopus, and Cochrane databases were searched from inception to June 2021. Cohort studies and randomized controlled trials (RCTs) were included. The effect sizes were estimated as log risk ratios and standard mean differences (SMDs) with 95% confidence intervals (CIs). The Newcastle–Ottawa score and Cochrane Collaboration’s tool were used to assess the risk of bias in cohort studies and RCTs, respectively.

Results

Of the 1,687 screened studies, 31 cohort studies and five RCTs met the eligibility criteria for qualitative analysis; 26 cohort studies and two RCTs were included in the meta-analysis. In the cohort studies, high adherence to the MeDi diet was associated with lower risk of mild cognitive impairment (MCI) [risk ratio (RR) = 0.75 (0.66–0.86)], and Alzheimer’s disease (AD) [RR = 0.71 (0.56–0.89)]. In the RCTs, high adherence to the MeDi diet was associated with better episodic [SMD = 0.20 (0.09–0.30)] and working memories [SMD = 0.17 (0.01–0.32)] than lowest group.

Conclusion

Adherence to the MeDi diet may reduce the risk of MCI and AD. However, other associations with cognitive outcomes (global cognition, working memory, and episodic memory) remain open to interpretation. Overall, the MeDi diet is recommended to prevent or delay cognitive disorders and improve cognitive function. Further, long-term RCTs are warranted to strengthen the evidence.

Systematic review registration

[https://www.crd.york.ac.uk], identifier [CRD42021276801].

Grip Strength Trajectories and Cognition in English and Chilean Older Adults: A Cross-Cohort Study

Growing evidence about the link between cognitive and physical decline suggests the early changes in physical functioning as a potential biomarker for cognitive impairment. Thus, we compared grip-strength trajectories over 12-16 years in three groups classified according to their cognitive status (two stable patterns, normal and impaired cognitive performance, and a declining pattern) in two representative UK and Chilean older adult samples. The samples consisted of 7069 UK (ELSA) and 1363 Chilean participants (ALEXANDROS). Linear Mixed models were performed. Adjustments included socio-demographics and health variables. The Declined and Impaired group had significantly lower grip-strength at baseline when compared to the Non-Impaired. In ELSA, the Declined and Impaired showed a faster decline in their grip strength compared to the Non-Impaired group but differences disappeared in the fully adjusted models. In ALEXANDROS, the differences were only found between the Declined and Non-Impaired and they were partially attenuated by covariates. Our study provides robust evidence of the association between grip strength and cognitive performance and how socio-economic factors might be key to understanding this association and their variability across countries. This has implications for future epidemiological research, as hand-grip strength measurements have the potential to be used as an indicator of cognitive performance.

Association between the frailty index and vascular brain damage: The Treviso Dementia (TREDEM) registry

PURPOSE

An association between frailty and vascular brain damage (VBD) has been described in older adults. However, most studies have identified frailty according to the phenotypic model. It is less clear whether frailty, operationalized as an accumulation of health deficits, is associated with the presence and severity of VBD. The present study was therefore undertaken to verify whether a 50-item frailty index (FI) is related to VBD in a large and relatively unselected cohort of attendees of a memory clinic.

MATERIALS AND METHODS

The TREDEM (Treviso Dementia) registry includes retrospective observational data of 1584 participants. A modified FI was calculated from 50 variables comprising diseases, disability, behavioral disorders, and blood biochemistry. The presence and severity of VBD, including leukoaraiosis, lacunes, larger infarctions and the hierarchical vascular rating scale (HVRS), were determined based on brain computerized tomography imaging. Multiple logistic regression models were built according to the stepwise method.

RESULTS

Mean age of the 1584 participants was 79.6 ± 7.5 years and 1033 (65.2 %) were females. The average number of health deficits was 11.6 ± 6.2, corresponding to an FI of 0.23 ± 0.12 (range: 0.00-0.56). Each 0.01-point increase in the FI was associated with an increased probability of leukoaraiosis (+2.3 %) and severe leukoaraiosis (+5 %), lacunas in the basal ganglia (+1.73 %), occipital lobes (+2.7 %), parietal lobes (+3 %), frontal lobes (+3.6 %), temporal lobes (+4.2 %), and thalamus (+4.4 %). Moreover, an increase of 0.01 points in the FI was associated with a 3.1 % increase in the probability of HVRS score (≥2).

CONCLUSION

An FI based on routine clinical and laboratory variables was associated with the presence, degree, and some localizations of VBD in a population of older adults with cognitive decline. This frailty assessment tool may therefore be used to identify individuals at risk of developing cerebrovascular disease and, consequently, to implement strategies for vascular risk factor control.

Association of waist-calf circumference ratio with incident cognitive impairment in older adults

BACKGROUND

The longitudinal relation of central fat and muscle mass with cognitive function remains unclear.

OBJECTIVES

We aimed to evaluate the relation of anthropometric measures, including BMI, waist circumference (WC), calf circumference (CC), and waist-calf circumference ratio (WCR), with incident cognitive impairment in older adults.

METHODS

A total of 3312 participants aged ≥65 y (mean: 81.8 y) who were free of cognitive impairment [the Chinese version of the Mini-Mental State Examination (MMSE) scores ≥24 points] in the Chinese Longitudinal Healthy Longevity Survey were included. The primary outcome was incident cognitive impairment, defined as MMSE scores <24 points at the exit visit. Secondary outcomes were incident cognitive decline, defined as a reduction of MMSE scores ≥3 points at the exit visit, and incident decline in different cognitive domains, defined as a reduction of MMSE scores in the domain ≥15% at the exit visit.

RESULTS

During a median follow-up duration of 3.6 y, 565 (17.1%) participants developed incident cognitive impairment. Overall, with mutual adjustments, higher WC [≥89 cm (fourth quartile) compared with <75 cm (first quartile); adjusted HR: 1.56; 95% CI: 1.19, 2.04] and higher WCR [≥2.9 (fourth quartile) compared with <2.4 (first quartile); adjusted HR: 1.96; 95% CI: 1.52, 2.52] were significantly associated with a higher risk of cognitive impairment, and higher CC [≥34 cm (fourth quartile) compared with <28 cm (first quartile); adjusted HR: 0.44; 95% CI: 0.33, 0.59] was associated with a lower hazard of cognitive impairment. Similar results were found for the secondary outcomes. However, BMI was not significantly associated with the study outcomes.

CONCLUSIONS

High WC and low CC were significantly associated with higher incident cognitive impairment in older adults. Moreover, WCR had a relatively stronger association with cognitive impairment compared with each circumference, suggesting maintaining both higher lean mass and lower central fat in older adults for the prevention of cognitive impairment.

Associations of body mass index, waist circumference and waist-to-height ratio with cognitive impairment among Chinese older adults: Based on the CLHLS

BACKGROUND

Few studies have been conducted on the associations of body mass index (BMI), waist circumference (WC), and waist-to-height ratio (WHtR) with cognitive impairment among Chinese older adults through a prospective design.

OBJECTIVE

This study was aimed to evaluate the associations of BMI, WC, and WHtR with cognitive impairment.

METHODS

We included participants aged 65 years and older in 2014 at baseline and 2018 follow-up surveys of the Chinese Longitudinal Healthy Longevity Survey (CLHLS). BMI, WC, and WHtR were calculated from measured weight, height, and waist circumference. Mini-Mental State Examination was utilized to assess cognitive impairment. Modified Poisson regression was used for calculating prevalence ratios, risk ratios, and 95% confidence intervals.

RESULTS

A total of 5156 participants were included in 2014 at baseline. The prevalence of cognitive impairment was 42.5%, 26.7%, and 21.2% in underweight, normal-weight, and overweight/obesity participants defined by BMI categories, respectively, and 24.1% and 26.8% in central obesity participants defined by WC and WHtR cutoffs, respectively. Prospectively, participants with underweight were more likely to suffer from cognitive impairment (RR = 1.258, 95% CI: [1.016, 1.559]), but no risk was found among participants with overweight/obesity after adjustment. Regardless of whether covariates were adjusted or not, no effect on cognitive impairment was found in participants with WC and WHtR groups in the follow-up survey.

CONCLUSIONS

Underweight may be a significant risk factor for the cognitive impairment of Chinese older adults. Weight management programs targeting older adults should attach importance to achieving and maintaining optimal body weight and improving cognitive function.

Adherence to Mediterranean Diet and Cognitive Abilities in the Greek Cohort of Epirus Health Study

The Mediterranean diet is commonly proposed as a major modifiable protective factor that may delay cognitive impairment in the elderly. The aim of the study was to investigate the cross-sectional association of adherence to the Mediterranean diet with cognitive abilities in a younger Greek population. A total of 1201 healthy adults aged 21-77 years (mean: 47.8) from the Epirus Health Study cohort were included in the analysis. Adherence to the Mediterranean diet was measured using the 14-point Mediterranean Diet Adherence Screener (MEDAS) and cognition was measured using the Trail Making Test, the Verbal Fluency test and the Logical Memory test. Statistical analysis was performed using multiple linear regression models adjusted for age, sex, education, body mass index, smoking status, alcohol consumption and physical activity. Overall, no association was found between the MEDAS score and cognitive tests, which could be explained by the young mean age and high level of education of the participants. Future studies should target young and middle-aged individuals to gain further understanding of the association between Mediterranean diet and cognition in this age group.

Longer Leukocytes Telomere Length Predicts a Significant Survival Advantage in the Elderly TRELONG Cohort, with Short Physical Performance Battery Score and Years of Education as Main Determinants for Telomere Elongation

Leukocyte telomere length (LTL) represents a key integrating component of the cumulative effects of environmental, lifestyle, and genetic factors. A question, however, remains on whether LTL can be considered predictive for a longer and healthier life. Within the elderly prospective TRELONG cohort (n = 612), we aimed to investigate LTL as a predictor of longevity and identify the main determinants of LTL among many different factors (physiological and lifestyle characteristics, physical performance and frailty measures, chronic diseases, biochemical measurements and apolipoprotein E genotyping). We found an ever-increasing relationship between LTL quartiles and survival. Hazard ratio analysis showed that for each unit increase in LTL and Short Physical Performance Battery (SPPB) scores, the mortality risk was reduced by 22.41% and 8.78%, respectively. Conversely, male gender, Charlson Comorbidity Index, and age threatened survival, with mortality risk growing by 74.99%, 16.57% and 8.5%, respectively. Determinants of LTL elongation were SPPB scores (OR = 1.1542; p = 0.0066) and years of education (OR = 1.0958; p = 0.0065), while male gender (OR = 0.4388; p =  0.0143) and increased Disease Count Index (OR = 0.6912; p  =  0.0066) were determinants of LTL attrition. Longer LTL predicts a significant survival advantage in elderly people. By identifying determinants of LTL elongation, we provided additional knowledge that could offer a potential translation into prevention strategies.

The role of diet on the risk of dementia in the oldest old: The Monzino 80-plus population-based study

BACKGROUND & AIMS

Longevity also carries its dark side of age-related chronic diseases, dementia being one of the worst and the most prevalent. Since dementia lacks effective treatments, preventing or delaying it is highly desirable. Dietary habits and nutrition have been found to be important modifiable risk factors for many chronic diseases, but evidence on the role of diet on the risk of dementia is still limited, particularly among the very old. Aim of the present work is to study the association of the Mediterranean diet and its components with prevalent and incident dementia in the oldest-old.

METHODS

We analyzed data from the Monzino 80-plus study, a population-based study in subjects 80 years or older in the Varese province, Italy. A validated food frequency questionnaire was used to collect information on 23 different foods consumed in the previous year. A Mediterranean diet score was calculated and its components were classified into tertiles. Multivariable models for dementia prevalence and incidence were adjusted for demographic and clinical characteristics.

RESULTS

Information on nutrition was available for 1390 subjects in the cross-sectional study and 512 subjects in the longitudinal study, mean respective ages 93 and 92. Greater adherence to Mediterranean diet, greater consumption of eggs, fruits and vegetables, carbohydrates, and greater food intake were associated with a lower prevalence of dementia. Increasing number of portions per week and consumption of legumes significantly decreased the incidence of dementia during the 3.6 year mean follow-up: corresponding hazard ratios of highest vs. lowest tertiles (95% confidence intervals) were 0.66 (0.46-0.95) and 0.68 (0.47-0.97), respectively.

CONCLUSION

Oldest-old eating less and having diets with less variety and nutrient density were more frequent among subjects with dementia. The longitudinal analysis confirmed oldest-old subjects who eat more portions, as well as those who have a higher intake of legumes, are at decreased risk of developing dementia even though reverse causality cannot be completely ruled out.

An update in toxicology of ageing

The field of ageing research has been rapidly advancing in recent decades and it had provided insight into the complexity of ageing phenomenon. However, as the organism-environment interaction appears to significantly affect the organismal pace of ageing, the systematic approach for gerontogenic risk assessment of environmental factors has yet to be established. This puts demand on development of effective biomarker of ageing, as a relevant tool to quantify effects of gerontogenic exposures, contingent on multidisciplinary research approach. Here we review the current knowledge regarding the main endogenous gerontogenic pathways involved in acceleration of ageing through environmental exposures. These include inflammatory and oxidative stress-triggered processes, dysregulation of maintenance of cellular anabolism and catabolism and loss of protein homeostasis. The most effective biomarkers showing specificity and relevancy to ageing phenotypes are summarized, as well. The crucial part of this review was dedicated to the comprehensive overview of environmental gerontogens including various types of radiation, certain types of pesticides, heavy metals, drugs and addictive substances, unhealthy dietary patterns, and sedentary life as well as psychosocial stress. The reported effects in vitro and in vivo of both recognized and potential gerontogens are described with respect to the up-to-date knowledge in geroscience. Finally, hormetic and ageing decelerating effects of environmental factors are briefly discussed, as well.

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.

Association Between Reading Habit and Sleep Among Age Over 40 Years Community Residents: A Population-Based Evidence Study

PURPOSE

Sleep disturbance is a paramount public health concern that besets many modern middle-aged and elderly community residents. Reading is important to adults as it facilitates the completion of daily tasks, and might be associated with sleep issues. The present study aimed to analyze the association between reading and sleep using Chinese national survey data.

PATIENTS AND METHODS

The 2018 China Family Panel Studies survey data were used, and the target sample was extracted according to age (>40 years). Reading behavior and reading quantity were chosen as independent variables, and sleep duration, sleep-onset time, and sleep quality were selected as dependent variables. A multilevel mixed linear/ordinal logistic regression model was employed to evaluate the association, and restricted cubic splines with 4 knots were employed to flexibly model the association of reading quantity and sleep duration.

RESULTS

A total of 18,740 adults were selected, and the reading rate was 15.04%. Reading habit was significantly negatively associated with weekday sleep duration, but not with duration at weekends, as determined from the full set of confounders adjusted models. Reading behavior was also associated with delayed sleep-onset time (OR: 0.935, 95% CI: 0.908-0.964), but not with sleep quality. Reading quantity showed a nonlinear relationship with sleep duration, appropriate reading quantity was related with long sleep duration.

CONCLUSION

Reading was associated with short sleep duration on weekdays, but not with sleep quality. Furthermore, reading was related to late sleep-onset time, and for the middle-aged and elderly Chinese populations, appropriate reading quantity was related with long sleep duration.

Cardiovascular risk factors and APOE-ε4 status affect memory functioning in aging via changes to temporal stem diffusion

Prior research investigating associations between hypertension, obesity, and apolipoprotein (APOE) genotype status with memory performance among older adults has yielded inconsistent results. This may reflect, in part, a lack of first accounting for the effects these variables have on structural brain changes, that in turn contribute to age-related memory impairment. The current study sought to clarify the relationships between these factors via path modeling. We hypothesized that higher body mass index (BMI), hypertension, and being an APOE-ε4 allele carrier would predict poorer memory scores, with much of these effects accounted for by indirect effects operating via differences in the integrity of temporal stem white matter. Participants included 125 healthy older adults who underwent neuropsychological assessment and diffusion-weighted MRI scanning. Direct effects were found for hypertension and demographic variables including age, sex, and education. Importantly, indirect effects were found for BMI, hypertension, APOE-ε4 status, age, and sex, where these factors predicted memory scores via their impact on temporal stem diffusion measures. There was also a dual effect of sex, with a direct effect indicating that females had better memory performance overall, and an indirect effect indicating that females with greater temporal stem diffusion had poorer memory performance. Results suggest that changes to the integrity of temporal white matter in aging may underpin reduced memory performance. These results highlight that accounting for variables that not only directly impact cognition, but also for those that indirectly impact cognition via structural brain changes, is crucial for understanding the impact of risk factors on cognition.

Social Isolation and Cognitive Function in Later Life: A Systematic Review and Meta-Analysis

BACKGROUND

There is some evidence to suggest that social isolation may be associated with poor cognitive function in later life. However, findings are inconsistent and there is wide variation in the measures used to assess social isolation.

OBJECTIVE

We conducted a systematic review and meta-analysis to investigate the association between social isolation and cognitive function in later life.

METHODS

A search for longitudinal studies assessing the relationship between aspects of social isolation (including social activity and social networks) and cognitive function (including global measures of cognition, memory, and executive function) was conducted in PsycInfo, CINAHL, PubMed, and AgeLine. A random effects meta-analysis was conducted to assess the overall association between measures of social isolation and cognitive function. Sub-analyses investigated the association between different aspects of social isolation and each of the measures of cognitive function.

RESULTS

Sixty-five articles were identified by the systematic review and 51 articles were included in the meta-analysis. Low levels of social isolation characterized by high engagement in social activity and large social networks were associated with better late-life cognitive function (r = 0.054, 95% CI: 0.043, 0.065). Sub-analyses suggested that the association between social isolation and measures of global cognitive function, memory, and executive function were similar and there was no difference according to gender or number of years follow-up.

CONCLUSIONS

Aspects of social isolation are associated with cognitive function in later life. There is wide variation in approaches to measuring social activity and social networks across studies which may contribute to inconsistencies in reported findings.

Association of anthropometric and nutrition status indicators with cognitive functions in centenarians

BACKGROUND & AIMS

How anthropometric and nutrition status indicators relate to cognitive function in the oldest old adults is an issue that needs to be explored. This study aimed to analyze the association of parameters and nutrition status indicators (waist circumference, BMI, calf circumference, and waist-calf circumference ratio [WCR]) with cognitive functions in centenarians.

METHODS

A cross-sectional observational study was conducted with the full sample of 1002 centenarians from Hainan. The mini-mental state examination (MMSE) was used to identify cognitive impairment. Multiple logistic regression analysis was used to examine the strength of association between each anthropometric index and the risk of cognitive impairment or severe cognitive impairment identified by MMSE. Locally Weighted Scatterplot Smoothing (LOWESS) curve was used to visualize the linear or non-linear relationship of each pair.

RESULTS

The risk of cognitive impairment identified by MMSE for centenarians was reduced by 12% for every 1 cm thickening of the calf circumference (OR = 0.88, 95% CI: 0.81-0.95) and the increase in each unit of WCR increased cognitive impairment the risk by 1.60 times (OR = 2.60, 95% CI: 1.31-5.13) after adjusting for demographic characteristics (i.e., gender, age, ethnicity, marital status, education level, and type of residence) and lifestyle (i.e., smoking, drinking, and exercise) related variables.

CONCLUSIONS

Results suggest that calf circumference is negatively associated with the risk of cognitive impairment identified by MMSE in centenarians. Older adults with lower calf circumference should pay attention to their cognitive function.

Cognitive Function Is a Prognostic Factor for Mortality of Nursing Home Residents during a 3-Year Observational Period

Introduction

Assessing cognitive function could help to provide appropriate care for nursing home residents. The aim of the study was to identify the factors affecting cognitive function in nursing home residents in Poland and assess how it influenced the mortality rate during a 3-year observational period.

Methods

This study included 202 elderly individuals from a nursing home in 2015. The investigation included examination of cognitive function using the MMSE and bioelectrical impedance analysis. Collected data included sex, age, blood pressure (BP), heart rate, number of comorbidities, years spent in the nursing home, educational level, and cigarette-smoking.

Results

The mean MMSE score was 21.36 ± 6.35, which was negatively correlated with age and diastolic BP (p = 0.001 and p = 0.024, respectively) and positively correlated with body mass, BMI, fat-free mass, fat, muscle mass, and education level (p = 0.004, p = 0.004, p = 002, p = 0.049, p = 0.005, and p ˂ 0.001, respectively). Patients who died during the observational period had lower MMSE scores than those who survived (23.34 ± 5.68 vs. 20.16 ± 6.45; p < 0.001). Smokers had better MMSE results than nonsmokers (23.34 ± 5.98 vs. 20.08 ± 4.94; p < 0.001).

Discussion

Polish nursing home residents had mild cognitive impairment depending on their age, sex, educational level, and nutritional status. Lower MMSE score was a prognostic factor for mortality in the 3-year observational period.

A Computerized Assessment of Verbal and Visuospatial Memory (Dys)functions in Patients with Rheumatoid Arthritis

Purpose

Rheumatoid arthritis (RA) is a chronic inflammatory systemic disease associated with various degrees of impairment across different cognitive domains. We aimed to provide a detailed computerized investigation of verbal and visuospatial short-term and working memory (dys)functions in RA patients, assessing both accuracy and response speed, while relating them to age, disease-related activity, affective problems, psychomotor speed and other clinical parameters.

Patients and Methods

The study included 29 RA patients (mean age 50.6 ± 12.3 years, 79% female) and 30 controls (matched according to age, gender and education), assessed with short-term and working memory tasks from the Cambridge Neuropsychological Test Automated Battery (CANTAB) and the Automated Working Memory Assessment (AWMA).

Results

RA patients were significantly slower on the basic processing speed test (Motor Screening Test, p =0.003). Their short-term information storage (verbal and visuospatial) was comparable to controls, yet this similar accuracy came at the expense of a longer response time to retain information correctly (on spatial span, p = 0.04). On tasks with higher executive demands, both visuospatial and verbal working memory were compromised, as RA patients took longer (p = 0.004) and had a higher number of total errors (p = 0.02) when conducting a strategic memory-guided search (Spatial Working Memory), and had a significantly lower verbal working memory span on the backwards digit recall test (p = 0.02).

Conclusion

The findings of this study emphasize the usefulness of performing computerized tests to detect subtle signs of cognitive impairment and of intact performance, which can inform memory training protocols for this vulnerable population.

"Camminando e Leggendo ... Ricordo" (Walking and Reading ... I Remember): Prevention of Frailty Through the Promotion of Physical Activity and Reading in People with Mild Cognitive Impairment. Results from the TREDEM Registry

BACKGROUND

Frailty is a condition of increased vulnerability to exogenous and endogenous stressors, which is correlated with aging, functional decline, institutionalization, hospitalization, and mortality. Given the multifaceted nature of frailty, programs aimed at its prevention are recommended to act on multiple domains.

OBJECTIVE

The present intervention program aimed at assessing the effects of combined physical and cognitive training in older people with mild cognitive impairment (MCI) and at investigating how their frailty status changed over one year of follow-up.

METHODS

Two-hundred and seven participants were recruited among outpatients of the Cognitive Impairment Center who agreed to receive a comprehensive assessment. Forty-six participants, who joined a structured program of physical activity and group readings for a period of one year, were defined as active. The remaining 161, who decided not to engage in those activities, were considered controls. In both groups, frailty status was assessed at baseline and over one year of follow-up.

RESULTS

Control participants showed twice the risk of becoming frail at 12 months compared with those in the active group. Participants in the active group had more than three times the probability of improving their frailty status compared with the control group from T0 to T12. Age and NPI scores were significantly associated with worsening frailty status. When analyses were restricted to participants who were robust at baseline, the frailty status varied significantly between groups over time.

CONCLUSION

Findings of the present study confirm the beneficial effects of physical activity and reading to prevent frailty in older people with MCI.

Volumetric reduction of cerebellar lobules associated with memory decline across the adult lifespan

Background

The human cerebellum plays an essential role in motor control, is involved in cognitive function and helps to regulate emotional responses. However, little is known about the relationship between cerebellar lobules and age-related memory decline. We aimed to investigate volume alterations in cerebellar lobules at different ages and assess their correlations with reduced memory recall abilities.

Methods

A sample of 275 individuals were divided into the following four groups: 20-35 years (young), 36-50 years (early-middle age), 51-65 years (late-middle age), and 66-89 years (old). Volumes of the cerebellar lobules were obtained using volBrain software. Analysis of covariance and post hoc analysis were used to analyze group differences in cerebellar lobular volumes, and multiple comparisons were performed using the Bonferroni method. Spearman correlation was used to investigate the relationship between lobular volumes and memory recall scores.

Results

In this study, we found that older adults had smaller cerebellar volumes than the other subjects. Volumetric decreases in size were noted in bilateral lobule VI and lobule crus I. Moreover, the volumes of bilateral lobule crus I, lobule VI, and right lobule IV were significantly associated with memory recall scores.

Conclusions

In the present study, we found that some lobules of the cerebellum appear more predisposed to age-related changes than other lobules. These findings provide further evidence that specific regions of the cerebellum could be used to assess the risk of memory decline across the adult lifespan.

Associations Between Aging-Related Changes in Grip Strength and Cognitive Function in Older Adults: A Systematic Review

OBJECTIVES

Grip strength and cognitive function reflect upper body muscle strength and mental capacities. Cross-sectional research has suggested that in old age these two processes are moderately to highly associated, and that an underlying common cause drives this association. Our aim was to synthesize and evaluate longitudinal research addressing whether changes in grip strength are associated with changes in cognitive function in healthy older adults.

METHODS

We systematically reviewed English-language research investigating the longitudinal association between repeated measures of grip strength and of cognitive function in community-dwelling older adults to evaluate the extent to which the two indices decline concurrently. We used four search engines: Embase, PsychINFO, PubMed, and Web of Science.

RESULTS

Of 459 unique citations, 6 met our full criteria: 4 studies reported a longitudinal association between rates of change in grip strength and cognitive function in older adults, 2 of which reported the magnitudes of these associations as ranging from low to moderate; 2 studies reported significant cross-sectional but not longitudinal associations among rates of change. All studies concluded that cognitive function and grip strength declined, on average, with increasing age, although with little to no evidence for longitudinal associations among rates of change.

CONCLUSIONS

Future research is urged to expand the study of physical and cognitive associations in old age using a within-person and multi-study integrative approach to evaluate the reliability of longitudinal results with greater emphasis on the magnitude of this association.

SYSTEMATIC REVIEW REGISTRATION NUMBER

CRD42016038544.

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.

Sex differences in the relationship between cognitive impairment and overweight or obesity in late life: A 3-year prospective study

The relationship between body weight changes in late life and cognitive function is controversial.We investigated whether weight gain or loss in late life affected cognitive function in community-dwelling older adults over a 3-year period.Our study used data from the Survey of Living Conditions and Welfare Needs of Korean Older Persons and included 3859 subjects (aged ≥65 years) with normal cognition at baseline. At baseline and the 3-year follow-up, body weight and height were measured, and cognitive function was assessed using the mini-mental state examination. Based on their body mass index (BMI) at baseline and follow-up, we divided the subjects into 4 groups: weight gain (baseline BMI <23 kg/m and follow-up BMI ≥23 kg/m); weight loss (baseline BMI ≥23 kg/m and follow-up BMI <23 kg/m); stable overweight/obese (BMI ≥23 kg/m at both visits); and stable non-overweight/obese (BMI <23 kg/m at both visits). Incidence rates (IRs) of cognitive impairment per 100 persons and IR ratios (IRRs) were calculated for each group and adjusted for confounding variables.At the 3-year follow-up, 610 cases of cognitive impairment (15.8%) were identified. The stable overweight/obese group had the lowest IR (14.0, 95% confidence interval [CI] 12.45-15.71) and was therefore used as the reference group when calculating IRRs for cognitive impairment. When men and women were evaluated separately, IRs between groups were significantly different only for women. The stable non-overweight/obese group (IRR 1.65, 95% CI 1.22-2.22) and the weight gain group (IRR 1.93, 95% CI 1.24-3.01) had higher IRs than those in the stable overweight/obese group. As a gain or loss of adiposity, the IR of the weight gain group (IRR 1.17, 95% CI 0.74-1.84) was not different from that of the stable non-overweight/obese group. Also, the IR of weight loss group (IRR 1.09, 95% CI 0.71-1.67) was not significantly different from that of the stable overweight/obese group.We suggest that overweight or obese older women at baseline had cognitive benefits. However, additional gain or loss of adiposity in late life did not affect the risk of cognitive impairment.

Combining modifiable risk factors and risk of dementia: a systematic review and meta-analysis

OBJECTIVE

To systematically review the literature relating to the impact of multiple co-occurring modifiable risk factors for cognitive decline and dementia.

DESIGN

A systematic review and meta-analysis of the literature relating to the impact of co-occurring key risk factors for incident cognitive decline and dementia. All abstracts and full text were screened independently by two reviewers and each article assessed for bias using a standard checklist. A fixed effects meta-analysis was undertaken.

DATA SOURCES

Databases Medline, Embase and PsycINFO were searched from 1999 to 2017.

ELIGIBILITY CRITERIA

For inclusion articles were required to report longitudinal data from participants free of cognitive decline at baseline, with formal assessment of cognitive function or dementia during follow-up, and an aim to examine the impact of additive or clustered comorbid risk factor burden in with two or more core modifiable risk factors.

RESULTS

Seventy-nine full-text articles were examined. Twenty-two articles (18 studies) were included reporting data on >40 000 participants. Included studies consistently reported an increased risk associated with greater numbers of intraindividual risk factors or unhealthy behaviours and the opposite for healthy or protective behaviours. A meta-analysis of studies with dementia outcomes resulted in a pooled relative risk for dementia of 1.20 (95% CI 1.04 to 1.39) for one risk factor, 1.65 (95% CI 1.40 to 1.94) for two and 2.21 (95% CI 1.78 to 2.73) for three or more, relative to no risk factors. Limitations include dependence on published results and variations in study outcome, cognitive assessment, length of follow-up and definition of risk factor exposure.

CONCLUSIONS

The strength of the reported associations, the consistency across studies and the suggestion of a dose response supports a need to keep modifiable risk factor exposure to a minimum and to avoid exposure to additional modifiable risks. Further research is needed to establish whether particular combinations of risk factors confer greater risk than others.

PROSPERO REGISTRATION NUMBER

42016052914.

Artificial Neural Networks Help to Better Understand the Interplay Between Cognition, Mediterranean Diet, and Physical Performance: Clues from TRELONG Study

BACKGROUND

Nutrition plays an important role in the aging process. Adherence to the Mediterranean diet (MedDiet) has been shown to be associated with lower rates of diseases. Cognitive status seems to be strongly interrelated with physical well-being, so that one influences the other. Physical performance measures are not only associated with clinical and subclinical age-related modifications, but are also able to predict disability, institutionalization, and mortality.

OBJECTIVE

To evaluate prospectively the associations between Mediterranean-Style Dietary Pattern Score (MSDPS), clinical characteristics, and cognition of the population sample of The TREVISO LONGEVA (TRELONG) Study, in Treviso, Italy.

METHODS

Global cognition, physical performance measures, MSDPS, and other clinical features were detected in 2010 in 82 men and 108 women. These characteristics were evaluated in relation to the physical performance measures identified 3.8 years later in 2013 in the same subjects, using a semantic connectivity map, through Auto-CM system, to grasp further and non-linear associations between variables which might remain, otherwise, undetected.

RESULTS

The Auto-CM system's map showed a close association between better levels of global cognition and MSDPS in 2010 and higher physical performance in 2013. On the other hand, worse levels of global cognition and MSDPS in 2010 were associated with lower physical performance in 2013.

CONCLUSION

The prevention models for successful aging may benefit from integrated programs that include cognitive, physical, and dietary interventions, since these aspects are mutually interrelated.

Body mass index, waist-to-hip ratio and cognitive function among Chinese elderly: a cross-sectional study

OBJECTIVES

To investigate the associations between body mass index (BMI), waist-to-hip ratio (WHR) and cognitive function among Chinese elderly.

DESIGN

Cross-sectional study.

SETTING

Community.

PARTICIPANTS

Data were obtained from the baseline survey of a community-based cohort in Zhejiang Province, and 9326 persons aged 60 years and older were enrolled.

PRIMARY OUTCOME MEASURES

We investigated the association between BMI and cognition, and then explored the association between WHR and cognition across different quartiles of BMI.

RESULTS

A sample of 9087 persons was used in this study, including 4375 men and 4712 women. Higher WHR increased cognitive impairment risk in those with BMI >25.3 kg/m² (OR (per 0.1 increase) 1.39; 95% CI 1.13 to 1.70). No statistically significant association was found in other BMI categories.

CONCLUSIONS

Higher WHR could increase the risk of cognitive impairment among elderly with BMI >25.3 kg/m². Our results suggest that it could be of benefit to the elderly with high BMI to control WHR.

Effect of combined bifidobacteria supplementation and resistance training on cognitive function, body composition and bowel habits of healthy elderly subjects

Physical exercise exerts favourable effects on brain health and quality of life of the elderly; some of these positive health effects are induced by the modulation of microbiota composition. We therefore conducted a randomised, double blind, placebo-controlled trial that assessed whether a combination of Bifidobacterium spp. supplementation and moderate resistance training improved the cognitive function and other health-related parameters in healthy elderly subjects. Over a 12-week period, 38 participants (66-78 years) underwent resistance training and were assigned to the probiotic Bifidobacterium supplementation (n=20; 1.25×10¹⁰ cfu each of Bifidobacterium longum subsp. longum BB536, B. longum subsp. infantis M-63, Bifidobacterium breve M-16V and B. breve B-3) or the placebo (n=18) group. At baseline and at 12 weeks, we assessed the cognitive function, using the Japanese version of the Montreal Cognitive Assessment instrument (MoCA-J); modified flanker task scores; depression-anxiety scores; body composition; and bowel habits. At 12 weeks, the MoCA-J scores showed a significant increase in both the groups, while the flanker task scores of the probiotic group increased more significantly than those of the placebo group (0.35±0.9 vs -0.29±1.1, P=0.056). Only the probiotic group showed a significant decrease in the depression-anxiety scores (5.2±6.3 to 3.4±5.5, P=0.012) and body mass index (24.0±2.8 to 23.5±2.8 kg/m², P<0.001), with a significant increase in the defecation frequency (5.3±2.3 to 6.4±2.3 times/5 days, P=0.023) at 12 weeks. Thus, in healthy elderly subjects, combined probiotic bifidobacteria supplementation and moderate resistance training may improve the mental condition, body weight and bowel movement frequency.

Get a grip: individual variations in grip strength are a marker of brain health

Demonstrations that grip strength has predictive power in relation to a range of health conditions-even when these are assessed decades later-has motivated claims that hand-grip dynamometry has the potential to serve as a "vital sign" for middle-aged and older adults. Central to this belief has been the assumption that grip strength is a simple measure of physical performance that provides a marker of muscle status in general, and sarcopenia in particular. It is now evident that while differences in grip strength between individuals are influenced by musculoskeletal factors, "lifespan" changes in grip strength within individuals are exquisitely sensitive to integrity of neural systems that mediate the control of coordinated movement. The close and pervasive relationships between age-related declines in maximum grip strength and expressions of cognitive dysfunction can therefore be understood in terms of the convergent functional and structural mediation of cognitive and motor processes by the human brain. In the context of aging, maximum grip strength is a discriminating measure of neurological function and brain health.

Body Mass and Physical Activity Uniquely Predict Change in Cognition for Aging Adults

BACKGROUND

Physical activity and body mass predict cognition in the elderly. However, mixed evidence suggests that obesity is associated with poorer cognition, while also protecting against cognitive decline in older age.

PURPOSE

We investigated whether body mass independently predicted cognition in older age and whether these associations changed over time.

METHODS

A latent curve structural equation modeling approach was used to analyze data from a sample of aging adults (N = 8442) split into two independent subsamples, collected over 6 years.

RESULTS

Lower baseline Body Mass Index (BMI) and higher physical activity independently predicted greater baseline cognition (p < 0.001). Decreases in BMI and physical activity independently predicted greater decline in the slope of cognition (p < 0.001).

CONCLUSIONS

Our results support the obesity paradox in cognitive aging, with lower baseline body mass predicting better cognition, but less decline over time protecting against cognitive decline. We discuss how weight loss in the elderly may serve as a useful indicator of co-occurring cognitive decline, and we discuss implications for health care professionals.

Relationships between cognitive function and body composition among community-dwelling older adults: a cross-sectional study

Background

Previous studies reported mixed results regarding the association between cognition and body weight in late life. We evaluated the relationships between cognitive function and body composition among community-dwelling older adults.

Methods

Three hundred twenty subjects (≥65 years, women 53%) with available data of cognitive function and body composition from 2010 Hallym Aging Study. Cognitive function was assessed using Korean Mini-Mental State Examination (K-MMSE). Dual-energy X-ray absorptiometry (DEXA) was used for measuring body composition including body fat and lean body mass. Anthropometric measurements and laboratory data were collected in clinical examination. Body composition variables were divided into sex-specific tertiles, and examined by multivariable logistic regression.

Results

Among female, the highest tertile group of fat mass and second tertile group of total lean body mass were associated with lower risk for cognitive impairment compared to the respective first tertile groups (odds ratios, 0.23 and 0.09, respectively; 95% confidence intervals, 0.04–0.88 and 0.01–0.44, respectively) after adjusting for confounding factors. In male, higher arm bone mineral content was associated with lower risk for cognitive impairment, but significance was lost after adjusting for adiponectin, age, and education.

Conclusions

Higher fat mass and lean body mass were associated with lower risk of cognitive impairment in older women. These observations suggest that body fat and lean mass later in life might be beneficial for cognition.

Electronic supplementary material

The online version of this article (10.1186/s12877-017-0651-9) contains supplementary material, which is available to authorized users.

Predictors of Memory in Healthy Aging: Polyunsaturated Fatty Acid Balance and Fornix White Matter Integrity

Recent evidence demonstrates that age and disease-related decline in cognition depends not only upon degeneration in brain structure and function, but also on dietary intake and nutritional status. Memory, a potential preclinical marker of Alzheimer’s disease, is supported by white matter integrity in the brain and dietary patterns high in omega-3 and omega-6 polyunsaturated fatty acids. However, the extent to which memory is supported by specific omega-3 and omega-6 polyunsaturated fatty acids, and the degree to which this relationship is reliant upon microstructure of particular white matter regions is not known. This study therefore examined the cross-sectional relationship between empirically-derived patterns of omega-3 and omega-6 polyunsaturated fatty acids (represented by nutrient biomarker patterns), memory, and regional white matter microstructure in healthy, older adults. We measured thirteen plasma phospholipid omega-3 and omega-6 polyunsaturated fatty acids, memory, and regional white matter microstructure in 94 cognitively intact older adults (65 to 75 years old). A three-step mediation analysis was implemented using multivariate linear regressions, adjusted for age, gender, education, income, depression status, and body mass index. The mediation analysis revealed that a mixture of plasma phospholipid omega-3 and omega-6 polyunsaturated fatty acids is linked to memory and that white matter microstructure of the fornix fully mediates the relationship between this pattern of plasma phospholipid polyunsaturated fatty acids and memory. These results suggest that memory may be optimally supported by a balance of plasma phospholipid omega-3 and omega-6 polyunsaturated fatty acids through the preservation of fornix white matter microstructure in cognitively intact older adults. This report provides novel evidence for the benefits of plasma phospholipid omega-3 and omega-6 polyunsaturated fatty acid balance on memory and underlying white matter microstructure.

The Impact of the Mediterranean Diet on the Cognitive Functioning of Healthy Older Adults: A Systematic Review and Meta-Analysis

Evidence from epidemiologic studies suggests a relation between the Mediterranean diet (MeDi) and cognitive function, but results are inconsistent. Prior reviews have not provided pooled data from meta-analysis of longitudinal studies and randomized controlled trials (RCTs), or they included younger adult participants. This systematic review and meta-analysis examines the impact of the MeDi on the cognitive functioning of healthy older adults. Fifteen cohort studies with 41,492 participants and 2 RCTs with 309 and 162 participants in intervention and control groups, respectively, were included. The primary outcome of interest was cognitive function, divided into domains of memory and executive function. Meta-analysis of cohort studies revealed a significant association between MeDi and older adults' episodic memory (n = 25,369, r = 0.01, P = 0.03) and global cognition (n = 41,492, r = 0.05, P ≤ 0.001), but not working memory (n = 1487, r = 0.007, P = 0.93) or semantic memory (n = 1487, r = 0.08, P = 0.28). Meta-analysis of RCTs revealed that compared with controls, the MeDi improved delayed recall (n = 429, P = 0.01), working memory (n = 566, P = 0.03), and global cognition (n = 429, P = 0.047), but not episodic memory (n = 566, P = 0.15), immediate recall (n = 566, P = 0.17), paired associates (n = 429, P = 0.20), attention (n = 566, P = 0.69), processing speed (n = 566, P = 0.35), or verbal fluency (n = 566, P = 0.12). The strongest evidence suggests a beneficial effect of the MeDi on older adults' global cognition. This article discusses the influence of study design and components of the MeDi on cognitive function and considers possible mechanisms.

Handgrip strength as a means of monitoring progression of cognitive decline - A scoping review

Cognitive decline in older adults contributes to reduced ability to perform daily tasks and continued disuse leads to muscle weakness and potentiates functional loss. Despite explicit links between the motor and cognitive systems, few health care providers assess motor function when addressing the needs of individuals with cognitive loss. Early and easy measurable biomarkers of cognitive decline have the potential to improve care for individuals with dementia and mild cognitive impairment. The aim of this study was to conduct a systematic search to determine the relationship among handgrip strength, as a measure of global muscle strength, and cognitive decline over time. Fifteen prospective, cohort, longitudinal studies of adults >60years old who were healthy or at risk of cognitive decline at study onset were included in the review. Studies that investigated changes in cognition relative to baseline grip strength and, those that investigated changes in grip strength relative to cognitive function were revealed. Findings here support the use of handgrip strength as a way to monitor cognitive changes and show that reduced handgrip strength over time may serve as a predictor of cognitive loss with advancing age.

[The association between cognition and handgrip strength among the elderly: an integrative review]

The objective of this study is to identify researches that associated cognition and handgrip strength among the elderly. This is a bibliographic review, based on an integrative approach of articles published in the last five years, indexed in the PubMed, Lilacs and Scopus databases. Inclusion criteria were: observational or experimental studies with a sample of elderly people (aged 60 years or more); assessment of muscular strength using a manual dynamometer; seniors who had at least one cognitive assessment instrument. At the end of the search 10 articles were selected to examine cognitive function and statistical results in the sample. It was observed that most of the research was conducted among the elderly aged over 75 and the Mini Mental State Examination (MMSE) was identified as the scale most commonly used for global cognitive assessment. A significant association was identified between alterations in cognition and reduction of handgrip strength (HGS) in 90% of the articles included in this study. Results of this review suggest the influence of cognitive impairment on the muscular strength of the elderly, which can affect aspects of their functional capacity and consequent dependence.

Association between phthalate exposure and lower handgrip strength in an elderly population: a repeated-measures study

BACKGROUND

Decreased muscle strength can lead to adverse health outcomes in the elderly. A potential association between phthalate exposure and muscle strength was suggested previously, but has not been investigated directly. We hypothesized that phthalate exposure is associated with lower handgrip strength and that the association is modified by the dietary omega-6 to omega-3 ratio.

METHODS

We analyzed 1,228 participants (≥60 years of age) recruited in Seoul and Asan, Republic of Korea. The study participants were surveyed up to three times between 2012 and 2015. At every survey, we collected urine samples and measured handgrip strength twice for each hand. The associations between urine phthalate metabolite concentrations and handgrip strength were evaluated using linear mixed models. Based on dietary information from 391 individuals who participated in the first survey in Seoul, we evaluated the heterogeneity of the association for those with high and low omega-6 to omega-3 ratios, using 8.81 (the 75th quantile) as a cutoff value.

RESULTS

Log-transformed creatinine-adjusted concentrations of mono-(2-ethyl-5-oxohexyl phthalate (MEOHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono-n-butyl phthalate (MnBP) were inversely associated with all measured handgrip strengths (β = -0.69 to -0.42, all p-values < 0.05). Associations between phthalate biomarkers and handgrip strength did not differ by sex. When the dietary subgroup was stratified by the omega-6 to omega-3 ratio, the associations were stronger among participants with high ratios.

CONCLUSIONS

We found inverse associations between phthalate biomarkers and handgrip strength in the elderly; this association was modified by the dietary omega-6 to omega-3 ratio.

Biomarkers of Aging: From Function to Molecular Biology

Aging is a major risk factor for most chronic diseases and functional impairments. Within a homogeneous age sample there is a considerable variation in the extent of disease and functional impairment risk, revealing a need for valid biomarkers to aid in characterizing the complex aging processes. The identification of biomarkers is further complicated by the diversity of biological living situations, lifestyle activities and medical treatments. Thus, there has been no identification of a single biomarker or gold standard tool that can monitor successful or healthy aging. Within this short review the current knowledge of putative biomarkers is presented, focusing on their application to the major physiological mechanisms affected by the aging process including physical capability, nutritional status, body composition, endocrine and immune function. This review emphasizes molecular and DNA-based biomarkers, as well as recent advances in other biomarkers such as microRNAs, bilirubin or advanced glycation end products.

Association between the Mediterranean-style Dietary Pattern Score and Physical Performance: Results from TRELONG Study

OBJECTIVE

To determine the association between Mediterranean-Style Dietary Pattern Score and physical performance.

DESIGN

Data analysis of a longitudinal study of a representative, age stratified, population sample.

SETTING

The TREVISO LONGEVA (TRELONG) Study, in Treviso, Italy.

PARTICIPANTS

In 2010, 123 men and 181 women, age 77 years and over (mean age 86.3 ± 6.8 years).

MEASUREMENTS

Performing a logistic regression in a multivariate analysis, hand grip strength and Short Physical Performance Battery (SPPB) were tested in relation to Mediterranean-Style Dietary Pattern Score (MSDPS).

RESULTS

The hand grip mean value was 10.9 kg (± 9.5) and the SPPB score was 6.3 (± 3.8). The MSDPS mean value in this study sample was 38.1/100 (± 8.1). A significant association (p=0.036) between a high adherence to the Mediterranean diet (fourth quartile) and higher performance lower limbs (SPPB>7) was found. No correlation was reported for the hand grip strength.

CONCLUSION

We found an association statistically significant between a high adherence to the Mediterranean diet and higher physical performance.

Body fat and the cognitive pattern: A population-based study

OBJECTIVE

The relationship between body fatness and cognitive pattern at a population level was investigated.

METHODS

Among 500 unselected subjects from the general population, the role of body mass index (BMI) and body fat mass (BFM) on a mini-mental state examination (MMSE) and on a battery of paper and pencil neuropsychological tests was analyzed. Multiple linear regressions, accounting for potential confounders, were used.

RESULTS

In fully adjusted models, MMSE (coefficient +0.027, 95% confidence intervals, 0.017-0.177), the clock drawing test (+0.141, 0.053-0.226), and the trail making test A (+1.542, 0.478-2.607) were positively associated with BMI. Adding BFM to the models, no associations were observed. The tests were also positively associated with BFM (+0.056, 0.021-0.091; +0.063, 0.025-0.101; +0.592, 0.107-1.077; respectively). At analysis of covariance, the same tests were significantly better performed over 29.4 kg m(-2) of BMI. After adding BFM as further confounder, all differences in performance across BMI were no longer significant. The three tests were better performed over 34.6 kg of BFM.

CONCLUSIONS

Higher BMI and particularly higher BFM are positively associated with better performance at the cognitive tasks exploring selective attention and executive functions.