Cognitive decline and cardiometabolic risk among Hispanic and non-Hispanic white adults in the San Luis Valley Health and Aging Study

Physical Activity and Cognitive Decline Among Older Adults: A Systematic Review and Meta-Analysis

Importance

Physical activity is associated with the risk for cognitive decline, but much of the evidence in this domain comes from studies with short follow-ups, which is prone to reverse causation bias.

Objective

To examine how length of follow-up, baseline age, physical activity amount, and study quality modify the longitudinal associations of physical activity with cognition.

Data Sources

Observational studies of adults with a prospective follow-up of at least 1 year, a valid baseline cognitive measure or midlife cohort, and an estimate of the association of baseline physical activity and follow-up cognition were sought from PsycInfo, Scopus, CINAHL, Web of Science, SPORTDiscus, and PubMed, with the final search conducted on November 2, 2022.

Study Selection

Two independent researchers screened titles with abstracts and full-text reports.

Data Extraction and Synthesis

Two reviewers independently assessed study quality and extracted data. Pooled estimates of association were calculated with random-effects meta-analyses. An extensive set of moderators, funnel plots, and scatter plots of physical activity amount were examined. This study is reported following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline.

Main Outcomes and Measures

Pooled estimates of the associations between physical activity and global cognition, as well as specific cognitive domains, were examined.

Results

A total of 104 studies with 341 471 participants were assessed. Analysis of binary outcomes included 45 studies with 102 452 individuals, analysis of follow-up global cognition included 14 studies with 41 045 individuals, and analysis of change in global cognition included 25 studies with 67 463 individuals. Physical activity was associated with a decreased incidence of cognitive impairment or decline after correction for funnel plot asymmetry (pooled risk ratio, 0.97; 95% CI, 0.97-0.99), but there was no significant association in follow-ups longer than 10 years. Physical activity was associated with follow-up global cognition (standardized regression coefficient, 0.03; 95% CI, 0.02-0.03) and change in global cognition (standardized regression coefficient, 0.01; 95% CI, 0.01 to 0.02) from trim-and-fill analyses, with no clear dose-response or moderation by follow-up length, baseline age, study quality or adjustment for baseline cognition. The specific cognitive domains associated with physical activity were episodic memory (standardized regression coefficient, 0.03; 95% CI, 0.02-0.04) and verbal fluency (standardized regression coefficient, 0.05; 95% CI, 0.03-0.08).

Conclusions and Relevance

In this meta-analysis of the association of physical activity with cognitive decline, physical activity was associated with better late-life cognition, but the association was weak. However, even a weak association is important from a population health perspective.

Disparities of Subjective Cognitive Decline Among Native Hawaiians/Other Pacific Islanders, Asian Americans, and White Americans in Hawai'i: Behavioral Risk Factor Surveillance System 2015 and 2017

Existing research on subjective cognitive decline (SCD) among Native Hawaiians/Other Pacific Islanders (NHOPIs) is limited even though NHOPI adults have the highest prevalence of cardiovascular risk factors. In this study, we investigated SCD disparities among NHOPIs, Asian Americans, and White Americans and its contributing factors utilizing the 2015 and 2017 survey year data from the Behavioral Risk Factor Surveillance System (BRFSS) for Hawai'i State in the United States. The SCD prevalence was 11.9%, 8.97%, and 7.86% among NHOPIs, Whites, and Asians, respectively. Adjusting for sociodemographic and health behavioral variables, the prevalence ratios (PRs) of SCD were 1.37 (95% confidence interval [CI] = 1.05-1.78) for NHOPI versus Asian and 1.15 (95% CI = 0.89-1.50) for NHOPI versus Whites. The associations were weakened after adjusting for health conditions. Depressive disorders, coronary heart disease or myocardial infarction, stroke, and diabetes were associated with cognitive decline in the multivariate-adjusted model. NHOPIs experienced more SCD-related functional difficulties than other races.

Funding of Hispanic/Latino Health-Related Research by the National Institutes of Health: An Analysis of the Portfolio of Research Program Grants on Six Health Topic Areas

Hispanics/Latinos are expected to constitute 25% of the U.S. population by 2060. Differences in the prevalence of health risk factors, chronic diseases, and access to and utilization of health-care services between Hispanics/Latinos and other populations in the U.S. have been documented. This study aimed to describe and analyze the landscape of Research Program Grants (RPGs) funded by the National Institutes of Health (NIH) between 2008 and 2015 involving Hispanic/Latino health research in six health condition areas-asthma, cancer, dementia, diabetes, liver/gallbladder disease, and obesity-and to identify opportunities for continued research in these areas. Using an NIH internal search engine, we identified new and renewal Hispanic/Latino health RPGs searching for specific Hispanic/Latino identifiers in the Title, Abstract, and Specific Aims. We used descriptive statistics to examine the distribution of funded RPGs by NIH disease-based classification codes for the six health condition areas of interest, and other selected characteristics. The most prominent clusters of research subtopics were identified within each health condition area, and performance sites were mapped at the city level. Within the selected time frame, 3,221 Hispanic/Latino health-related unique RPGs were funded (constituting 4.4% of all funded RPGs), and of those 625 RPGs were eligible for review and coding in the present study. Cancer and obesity were the most commonly studied health condition areas (72%), while studies on mechanisms of disease-biological and non-biological-(72.6%), behavioral research (42.1%) and epidemiological studies (38.1%) were the most common types of research. Most of the primary performance sites were in California, Texas, the northeastern U.S., and Illinois. The predominance of mechanistic, behavioral, and epidemiological studies in our analysis poses opportunities to evaluate knowledge gained and their clinical application, explore new research questions, or to update some methods or instruments. The findings of the present study suggest opportunities to expand research in understudied mechanisms of disease that could explain differences in prevalence of conditions like diabetes and cancer among different heritage groups. In addition, our findings suggest that the impact of interventions or policies designed to reduce health disparities, innovative multi-level interventions, implementation and dissemination studies, the role of health information technology on health outcomes, and the intersectionality of individual, sociocultural, geographic, and other factors on health outcomes, among others, are understudied approaches, which could potentially advance research in Hispanic/Latino health and contribute to the achievement of better health outcomes in this diverse population.

Body mass index across adult life and cognitive function in the American elderly

This study aimed to examine the associations of body mass index (BMI) across adult life with cognitive function in 2,637 participants aged 60 years or over from NHANES 2011-2014. The primary outcome was a composite score based on test scores on word list learning, animal naming, and digit symbol substitution. Exposures of interest included BMI at age 25, BMI 10 years before the survey, BMI at the survey (current BMI), and BMI burden calculated from age 25 to age at survey. BMI at age 25 was inversely associated with the composite score (β=-0.0271±0.0130 per kg/m², P=0.038) and positively with low cognitive performance (odd ratio=1.04, 95% confidence interval: 1.01-1.07, P=0.010), defined as below 20 percentile of the composite score. Similar results were observed for BMI 10 years before the survey and BMI burden. Current BMI was positively associated with the composite score (β=0.0369±0.0113, P=0.001) and inversely associated with low cognitive performance (odd ratio=0.96, 95% confidence interval: 0.94-0.99, P=0.004). In conclusion, high BMI in early adult life is associated with low cognitive function in late life, which underscores the importance of a healthy body weight across the life course. The association between BMI and cognitive function at late life requires further investigation.

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.

The modifying effect of positive emotion on the relationship between cognitive impairment and disability among older Mexican Americans: a cohort study

OBJECTIVE

To determine if positive emotion modifies the relationship between cognitive impairment and activities of daily living disability status over 10 years in Mexican American adults aged 75 years and older.

METHODS

A retrospective cohort design using data from the Hispanic established populations for the epidemiologic studies of the elderly. About 2674 participants aged 75 years and older were included and followed over 10 years. Cognition was measured using the mini-mental state examination, positive emotion was measured using four questions from the Center for Epidemiologic Studies Depression Scale, and disability was measured using seven activities of daily living items. A series of generalized estimating equations models were used, with the initial analysis including those with disability at baseline and subsequent analyses excluding disability at baseline.

RESULTS

Positive emotion and cognitive impairment consistently decreased and increased risk for activities of daily living disability, respectively. Positive emotion was a significant modifier in the cross-sectional analysis, and was not a statistically significant modifier in the longitudinal or predictive series analysis.

CONCLUSIONS

Positive emotion and cognitive impairment differentially affect the risk of developing activities of daily living disability. Further research is needed to explore the interaction of positive emotion and cognitive impairment, and to identify appropriate interventions that address the specific cognitive and emotional needs of older Mexican Americans. Implications for rehabilitation Promoting emotional well-being may be protective against incident disability for older adults. Cognitive impairment significantly predicts incident disability in activities of daily living and should be considered an early indicator of impending disability for older adults.

Factors affecting aging cognitive function among community-dwelling older adults

AIM

The study purpose was to determine factors affecting aging cognitive function of 3,645 community-dwelling older adults in Korea.

METHODS

The Hasegawa Dementia Scale assessed aging cognitive function, blood analyses and anthropometrics assessed cardio-metabolic risk factors, and the Geriatric Depression Scale Short Form Korean Version assessed depressive symptoms.

RESULTS

Participants with poor aging cognitive function were more likely to be in the late age group (≥75 y) and currently smoking and have a medical history of stroke, high body mass index, and high level of depressive symptoms; they were also less likely to engage in regular meals and physical activities.

CONCLUSION

Regular meals and physical activities may be primary factors for clinical assessment to identify older adults at risk for aging cognitive function. With aging, depressive symptoms and other unhealthy lifestyle behaviours should be managed to prevent cognitive function disorders.

Change in Cognitive Abilities in Older Latinos

The aim of this study was to compare patterns of cognitive decline in older Latinos and non-Latinos. At annual intervals for a mean of 5.7 years, older Latino (n=104) and non-Latino (n=104) persons of equivalent age, education, and race completed a battery of 17 cognitive tests from which previously established composite measures of episodic memory, semantic memory, working memory, perceptual speed, and visuospatial ability were derived. In analyses adjusted for age, sex, and education, performance declined over time in each cognitive domain, but there were no ethnic group differences in initial level of function or annual rate of decline. There was evidence of retest learning following the baseline evaluation, but neither the magnitude nor duration of the effect was related to Latino ethnicity, and eliminating the first two evaluations, during which much of retest learning occurred, did not affect ethnic group comparisons. Compared to the non-Latino group, the Latino group had more diabetes (38.5% vs. 25.0; χ2[1]=4.4; p=.037), fewer histories of smoking (24.0% vs. 39.4%, χ2[1]=5.7; p=.017), and lower childhood household socioeconomic level (-0.410 vs. -0.045, t[185.0]=3.1; p=.002), but controlling for these factors did not affect results. Trajectories of cognitive aging in different abilities are similar in Latino and non-Latino individuals of equivalent age, education, and race. (JINS, 2016, 22, 58-65).