Multiple Influences on Cognitive Function Among Urban-Dwelling African Americans.

This study examined multiple influences on cognitive function among African Americans, including education, literacy, poverty status, substance use, depressive symptoms, and cardiovascular disease (CVD) risk factors. Baseline data were analyzed from the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study. Participants were 987 African Americans (mean age 48.5 years, SD = 9.17) who completed cognitive measures assessing verbal learning and memory, nonverbal memory, working memory, verbal fluency, perceptuo-motor speed, attention, and cognitive flexibility. Using preplanned hierarchical regression, cognitive performance was regressed on the following: (1) age, sex, education, poverty status; (2) literacy; (3) cigarette smoking, illicit substance use; (4) depressive symptoms; and (5) number of CVD risk factors. Results indicated that literacy eliminated the influence of education and poverty status in select instances, but added predictive utility in others. In fully adjusted models, results showed that literacy was the most important influence on cognitive performance across all cognitive domains (p < .001); however, education and poverty status were related to attention and cognitive flexibility. Depressive symptoms and substance use were significant predictors of multiple cognitive outcomes, and CVD risk factors were not associated with cognitive performance. Overall, findings underscore the need to develop cognitive supports for individuals with low literacy, educational attainment, and income, and the importance of treating depressive symptoms and thoroughly examining the role of substance use in this population.

Dietary Protein Intake and Overall Diet Quality Are Associated with Handgrip Strength in African American and White Adults.

OBJECTIVE: To determine the association of handgrip strength (HS) with protein intake, diet quality, and nutritional and cardiovascular biomarkers in African American and White adults. DESIGN: Cross-sectional wave 3 (2009-2013) of the cohort Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study. PARTICIPANTS: Socioeconomically diverse urban population of 2,468 persons aged 33 to 71 years. MEASUREMENTS: Socio-demographic correlates, dietary intakes and biomarkers, HS, physical performance measures were collected. HS was measured using a dynamometer with the dominant hand. Functional measures included chair, tandem, and single leg stands. Two 24-hour recalls were collected using the US Department of Agriculture Automated Multiple Pass Method. The total protein intake and diet quality, evaluated by adherence to the DASH eating plan and Healthy Eating Index-2010, were calculated. Biomarkers included nutritional anemia, and serum levels of albumin, cholesterol, magnesium, and glucose. RESULTS: The mean ±SE age of the sample was 52.3±0.2 years. Approximately 61% were African American and 57% were women. The mean ±SE HS of women was 29.1±0.2kg and for men was 45.9±0.4 kg. Protein, gm, per kg body weight for the women was 0.94±0.02 compared to 1.16 ±0.02 for men. After adjusting for socio-demographic factors, hypertension, and diabetes, HS/BMI ratio was significantly associated with protein intake per kg body weight (p<0.001) and diet quality, assessed by either the DASH adherence (p=0.009) or Health Eating Index-2010 (p=0.031) scores. For both men and women, participants in the upper tertile of HS maintained a single leg and tandem stances longer and completed 5 and 10 chair stands in shorter time compared to individuals in the lower HS tertile. Of the nutritional status indicators, the percent of men in the upper HS tertile with low serum magnesium and albumin, was significantly lower than those in the lower HS tertile [magnesium,7.4% vs 16.1%; albumin, 0.4% vs 4.5%]. The only difference observed for women was a lower percent of diabetes (14.4% for the upper HS tertile compared to 20.5% for the lower HS tertile. CONCLUSIONS: The findings confirm the role of protein and a healthful diet in the maintenance of muscle strength. In this community sample, HS was significantly associated with other physical performance measures but did not appear to be strongly associated with indicators of nutritional risk. These findings support the use of HS as a proxy for functional status and indicate the need for research to explore its role as a predictor of nutritional risk.

Racial disparities in adult all-cause and cause-specific mortality among us adults: mediating and moderating factors.

BACKGROUND: Studies uncovering factors beyond socio-economic status (SES) that would explain racial and ethnic disparities in mortality are scarce. METHODS: Using prospective cohort data from the Third National Health and Nutrition Examination Survey (NHANES III), we examined all-cause and cause-specific mortality disparities by race, mediation through key factors and moderation by age (20-49 vs. 50+), sex and poverty status. Cox proportional hazards, discrete-time hazards and competing risk regression models were conducted (N = 16,573 participants, n = 4207 deaths, Median time = 170 months (1-217 months)). RESULTS: Age, sex and poverty income ratio-adjusted hazard rates were higher among Non-Hispanic Blacks (NHBs) vs. Non-Hispanic Whites (NHW). Within the above-poverty young men stratum where this association was the strongest, the socio-demographic-adjusted HR = 2.59, p < 0.001 was only partially attenuated by SES and other factors (full model HR = 2.08, p = 0.003). Income, education, diet quality, allostatic load and self-rated health, were among key mediators explaining NHB vs. NHW disparity in mortality. The Hispanic paradox was observed consistently among women above poverty (young and old). NHBs had higher CVD-related mortality risk compared to NHW which was explained by factors beyond SES. Those factors did not explain excess risk among NHB for neoplasm-related death (fully adjusted HR = 1.41, 95 % CI: 1.02-2.75, p = 0.044). Moreover, those factors explained the lower risk of neoplasm-related death among MA compared to NHW, while CVD-related mortality risk became lower among MA compared to NHW upon multivariate adjustment. CONCLUSIONS: In sum, racial/ethnic disparities in all-cause and cause-specific mortality (particularly cardiovascular and neoplasms) were partly explained by socio-demographic, SES, health-related and dietary factors, and differentially by age, sex and poverty strata.

White blood cell inflammatory markers are associated with depressive symptoms in a longitudinal study of urban adults.

Total white blood cell count (TWBCC) and percentage (%) composition of lymphocytes (PL) or neutrophils (PN) are linked to mid- and late-life depression, though sex-specific temporal relationships between those inflammatory markers and depressive symptoms remain unclear. The association between inflammation and depressive symptoms in longitudinal data on ethnically and socioeconomically diverse urban adults was examined with two hypotheses. In hypothesis 1, we examined the relationship between TWBCC, PL and PN with change in level of depressive symptoms from baseline to follow-up, stratifying by sex. In hypothesis 2, we examined reverse causality, by testing the relationship of depressive symptoms with change in TWBCC, PL and PN. Multiple linear mixed-effects regression models were performed to examine both the hypotheses. The sample sizes of participants (n) and repeated observations (n') were: Hypothesis 1 (n=2009; n'=3501); Hypothesis 2 (n=2081; n'=3560). Among key findings (Hypothesis 1), in women, higher TWBCC was linked to a faster increase in depressive symptom total score (γ1112±s.e.: +0.81±0.28, P=0.003), with a slower increase over time in the positive affect subdomain coupled with faster increases in depressed affect and somatic complaints. Among women, baseline score on somatic complaints was positively associated with low PN (γ01a=+1.61±0.48, P<0.001) and high PL (γ01a=+1.16±0.45, P=0.011), whereas baseline score on positive affect was inversely related to higher PL (γ01a=-0.69±0.28, P=0.017). Results among men indicated that there was a positive cross-sectional relationship between low TWBCC and depressive symptoms, depressed affect and an inverse cross-sectional relationship with positive affect. However, over time, a low TWBCC in men was linked to a higher score on positive affect. There was no evidence of a bi-directional relationship between WBC parameters and depressive symptoms (Hypothesis 2). In sum, TWBCC and related markers were linked to depressive symptoms, mostly among women. Further longitudinal studies are needed to replicate this sex-specific association.

Total serum cholesterol, atherogenic indices and their longitudinal association with depressive symptoms among US adults.

Serum cholesterol, both total and lipoprotein fractions, has been associated with mid- and late-life depression. Using longitudinal data on a large and ethnically diverse sample of urban adults, the associations of serum lipid profile measured by high or low total cholesterol (TC; >200 mg dl(-1); <160 mg dl(-1)) and by atherogenic indices, namely high total cholesterol and low-density lipoprotein cholesterol relative to high-density lipoprotein cholesterol, with change in total and domain-specific depressive symptoms over time were examined. Findings were compared by sex. (Hypothesis 1) In addition, baseline depressive symptoms as predictors for longitudinal change in lipid profile trajectory were tested. (Hypothesis 2) Mixed-effects regression analyses stratified by sex was used. Sample sizes of participants (n) and repeated observations (n') were: Hypothesis 1 (Men: n=826 ; n'=1319; Women: n=1099 ; n'=1817); Hypothesis 2 (Men: n=738; n'=1230; Women: n=964; n'=1678). As hypothesized, a higher level of atherogenic indices was linked to faster increase in depressive symptom scores, particularly depressed affect and interpersonal problems, though this relationship was found only among women. Among men a U-shaped relationship between baseline TC and longitudinal increase in somatic complaints and a direct link between low TC and longitudinal putative improvement in positive affect was found. On excluding statin users among women, low TC was associated with slower increase in depressed affect over time, whereas high TC was associated with faster increase in interpersonal problems. In summary, atherogenic indices were directly linked to faster increase in depressive symptoms among women only. More studies are needed to explain these sex-specific associations.

Thyroid hormones are associated with cognitive function: moderation by sex, race, and depressive symptoms.

CONTEXT: Recent evidence indicates that thyroid hormones may be closely linked to cognition among adults. OBJECTIVE: We investigated associations between thyroid hormones and cognitive performance, while testing effect modification by sex, race, and elevated depressive symptoms (EDS). DESIGN: This cross-sectional study used extensive data from the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study. SETTING: The study was conducted in Baltimore, Maryland, from 2004 to 2009. PARTICIPANTS: PARTICIPANTS were U.S. adults aged 30 to 64 years. The sample size ranged from 1275 to 1346. MAIN OUTCOME MEASURES: Outcomes included 13 cognitive test scores spanning domains of learning/memory, language/verbal, attention, visuo-spatial/visuo-construction, psychomotor speed, executive function, and mental status. RESULTS: Within reference ranges and after Bonferroni correction, elevated free thyroxine (fT4) was associated with better performance on tests of visuo-spatial/visuo-construction ability (overall, women, and African Americans) and learning/memory (women and African Americans), whereas a higher total thyroxine (tT4) level was associated with better performance in the domain of psychomotor speed (individuals without EDS) and higher levels of both fT4 and tT4 were linked to better language/verbal test performance among men. In contrast, higher T3(% uptake) was related to better performance on tests of visuo-spatial/visuo-construction ability and psychomotor speed among whites. When the above reference range was compared within the overall population and after Bonferroni correction, a within reference range fT4 was linked to better performance on visuo-spatial/visuo-constrution ability and psychomotor speed, whereas a below normal range TSH level (compared with the reference range) was linked to better performance in domains of psychomotor speed and attention. CONCLUSIONS: Thyroid hormones and cognition are closely linked differentially by sex, race, and EDS status.

Depressive symptoms are associated with weight gain among women.

BACKGROUND: Many studies have linked depression and obesity; few have more than two assessments of depressive symptoms and adiposity to address the potential bidirectional relationship between adiposity and depressive symptoms from young adulthood through old age. We tested whether baseline depressive symptoms are associated with changes in weight, whether baseline adiposity is associated with changes in depressive symptoms, and whether these associations vary by sex. METHOD: Participants (n=2251; 47% female) were from the Baltimore Longitudinal Study of Aging (BLSA). Using hierarchical linear modeling (HLM) on 30 years of data, the trajectory of adiposity and depressive symptoms over adulthood was estimated from >10 000 observations (mean=4.5 assessments per participant) of body mass index (BMI; kg/m2), waist circumference and hip circumference and >10 000 observations (mean=4.5 assessments per participant) of the Center for Epidemiological Studies Depression Scale (CES-D). Baseline depressive symptoms and adiposity were then tested as predictors of the trajectory of adiposity and depressive symptoms respectively. Additional analyses tested for sex-specific associations. RESULTS: Sex moderated the association between depressive symptoms and weight gain such that women who experienced depressed affect had greater increases in BMI (b(interaction)=0.12, S.E.=0.04), waist (b(interaction)=0.22, S.E.=0.10) and hip circumference (b(interaction)=0.20, S.E.=0.07) across the adult lifespan, controlling for relevant demographic and behavioral covariates. Baseline adiposity was unrelated to the trajectory of depressive symptoms (median b=0.00) for both sexes. CONCLUSIONS: Women who experience symptoms of depression tend to gain more weight across adulthood than men who experience such symptoms. Whether an individual was normal weight or overweight was unrelated to changes in depressive symptoms across adulthood.

Associations among 25-hydroxyvitamin D, diet quality, and metabolic disturbance differ by adiposity in adults in the United States.

CONTEXT: Recent evidence indicates that a higher plasma level of 25-hydroxyvitamin D [25(OH)D] is associated with lower adiposity and a reduced number of metabolic disturbances (MetD). OBJECTIVES: We examined associations among dietary quality, 25(OH)D, percent body fat (%BF), and MetD, and a pathway linking them, across central obesity. DESIGN: This cross-sectional nationally representative study used extensive data from the National Health and Nutrition Examination Surveys of 2001-2004. PARTICIPANTS: U.S. adults aged at least 20 yr were stratified by central obesity (CO) status. Sample sizes ranged from 1943 (all MetD combined) to 7796 (each component). MAIN OUTCOME MEASURES: %BF was measured using dual-energy x-ray absorptiometry, and MetD was measured with individual continuous nonadiposity outcomes (e.g. fasting plasma glucose) and with a composite count index of binary MetD with prespecified cutoff points (Index I). RESULTS: A higher 25(OH)D was associated with better dietary quality, lower %BF, and lower number of MetD. These inverse 25(OH)D-%BF and 25(OH)D-MetD associations (i.e. fasting blood glucose, homeostatic model assessment of insulin resistance, C-reactive protein, and Index I) were significantly stronger among the CO+ group. Finally, the pathway linking the dairy component of the Healthy Eating Index (HEIdairy) to Index I through 25(OH)D and %BF indicated complete mediation among the CO- group, but HEIdairy and 25(OH)D had direct inverse associations with Index I among the CO+ group. CONCLUSIONS: Due to potential genetic differences between CO- and CO+ groups, empowering U.S. adults with central obesity to make related behavioral changes may be especially effective in improving their vitamin D status and metabolic profile.

No advantage of A beta 42-lowering NSAIDs for prevention of Alzheimer dementia in six pooled cohort studies.

INTRODUCTION: Observational studies show reduced incidence of Alzheimer dementia (AD) in users of nonsteroidal anti-inflammatory drugs (NSAIDs). One hypothesis holds that the subset of NSAIDs known as selective A beta(42)-lowering agents (SALAs) is responsible for this apparent reduction in AD risk. METHODS: We pooled individual-level data from six prospective studies to obtain a sufficient sample to examine AD risk in users of SALA vs non-SALA NSAIDs. RESULTS: Of 13,499 initially dementia-free participants (70,863 person-years), 820 developed incident AD. Users of NSAIDs (29.6%) showed reduced risk of AD (adjusted hazard ratio [aHR] 0.77, 95% CI 0.65-0.91). The point estimates were similar for SALAs (aHR 0.87, CI 0.72-1.04) and non-SALAs (aHR 0.75, CI 0.56-1.01). Because 573 NSAID users (14.5%) reported taking both a SALA and non-SALA, we examined their use alone and in combination. Resulting aHRs were 0.82 (CI 0.67-0.99) for SALA only, 0.60 (CI 0.40-0.90) for non-SALA only, and 0.87 (CI 0.57-1.33) for both NSAIDs (Wald test for differences, p = 0.32). The 40.7% of participants who used aspirin also showed reduced risk of AD, even when they used no other NSAIDs (aHR 0.78, CI 0.66-0.92). By contrast, there was no association with use of acetaminophen (aHR 0.93, CI 0.76-1.13). CONCLUSIONS: In this pooled dataset, nonsteroidal anti-inflammatory drug (NSAID) use reduced the risk of Alzheimer dementia (AD). However, there was no apparent advantage in AD risk reduction for the subset of NSAIDs shown to selectively lower A beta(42), suggesting that all conventional NSAIDs including aspirin have a similar protective effect in humans.

Effect of a clinical stroke on the risk of dementia in a prospective cohort.

OBJECTIVE: To examine the risk and determinants of dementia following a clinically overt stroke in a prospectively followed cohort of elderly subjects. METHODS: We examined the effect of a clinically detectable stroke on the risk of dementia using prospective data from 335 subjects in the Baltimore Longitudinal Study of Aging, all of whom were cognitively and neurologically normal at entry into the study (mean age at entry 75.1 +/- 4.2 years). RESULTS: Clinically overt strokes are common in our cohort (cumulative risk by age 90, 15.4%; 95% CI: 10 to 22%) and confer an increased risk of dementia compared to subjects without stroke (odds ratio [OR] 5.55; 95% CI: 2.76 to 11.4). The majority of patients who became demented after a stroke had evidence of mild cognitive impairment preceding the stroke (14 of 19). Moreover, a clinically symptomatic stroke was a major risk factor for the conversion of mild cognitive impairment to dementia (OR 12.4; 95% CI: 1.5 to 99). When cognitive impairment did not precede the stroke, there was no increase in the risk of subsequent dementia. Pathologic data indicate that both vascular and Alzheimer pathology leads to the prestroke impairment. CONCLUSION: Dementia after stroke may be determined by cognitive impairments that exist prior to the stroke.