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Background/objectives: To investigate potential mechanisms underlying the well-established relationship of diabetes and obesity with cognitive decline, among older adults participating in a population-based study., Design/setting: Ten-year population-based cohort study., Participants: A total of 478 individuals aged 65 years and older., Measurements: We assayed fasting blood for markers of glycemia (glucose and hemoglobin A1c [HbA1c]), insulin resistance (IR) (insulin and homeostatic model assessment of IR), obesity (resistin, adiponectin, and glucagon-like peptide-1), and inflammation (C-reactive protein). We modeled these indices as predictors of the slope of decline in global cognition, adjusting for age, sex, education, APOE*4 genotype, depressive symptoms, waist-hip ratio (WHR), and systolic blood pressure, in multivariable regression analyses of the entire sample and stratified by sex-specific median WHR. We then conducted WHR-stratified machine-learning (Classification and Regression Tree [CART]) analyses of the same variables., Results: In multivariable regression analyses, in the entire sample, HbA1c was significantly associated with cognitive decline. After stratifying by median WHR, HbA1c remained associated with cognitive decline in those with higher WHR. No metabolic indices were associated with cognitive decline in those with lower WHR. Cross-validated WHR-stratified CART analyses selected no predictors in participants older than 87 to 88 years. Faster cognitive decline was associated, in lower WHR participants younger than 87 years, with adiponectin of 11 or greater; and in higher WHR participants younger than 88 years, with HbA1c of 6.2% or greater., Conclusions: Our population-based data suggest that, in individuals younger than 88 years with central obesity, even modest degrees of hyperglycemia might independently predispose to faster cognitive decline. In contrast, among those younger than 87 years without central obesity, adiponectin may be a novel independent risk factor for cognitive decline. J Am Geriatr Soc 68:991-998, 2020., (© 2020 The American Geriatrics Society.)

The aim of the study was to determine whether the reduction in brain grey matter volume associated with hypertension persisted or was remediated among hypertensive patients newly treated over the course of a year. A total of 41 hypertensive patients were assessed over the course of a 1-year successful anti-hypertensive treatment. Brain areas identified previously in cross-sectional studies differing in volume between hypertensive and normotensive individuals were examined with a semi-automated measurement technique (automated labelling pathway). Volumes of grey matter regions were computed at baseline after a year of treatment and compared with archival data from normotensive individuals. Reductions in regional grey matter volume over the follow-up period were observed despite successful treatment of blood pressure (BP). The comparison group of older, but normotensive, individuals showed no significant changes over a year in the regions tested in the treated hypertensive group. These novel results suggest that essential hypertension is associated with regional grey matter shrinkage, and successful reduction of BP may not completely counter that trend.

Objective: Previous studies have suggested that high rates of recent alcohol or drug use are associated with increased risk for HIV infection in gay men. To examine whether this relationship is mediated by substance use per se or by more enduring patterns of problematic substance use, lifetime DSM-III-R alcohol and other drug dependence disorders were ascertained and used to predict self-reported serostatus., Method: Gay men (N = 187) who had been tested for HIV and knew their serostatus (31 are HIV+) completed demographic, drug use and sexual practices questionnaires. Formal DSM-III-R psychiatric diagnoses were made on the basis of an individual interview, using the Structured Clinical Interview for DSM-III-R., Results: Subjects had lifetime rates of alcohol dependence and drug dependence disorders that were two to three times higher than the general population, and 58% of the subjects who met criteria for alcohol dependence also met criteria for other substance dependence. Logistic regression analysis indicated that serostatus was best predicted by presence of both alcohol and drug dependence, and by race. When analyses were repeated in seronegative men, using unprotected anal sex as the outcome and recent substance use as predictors, no relationship between alcohol and behavior was found., Conclusions: Data do not support the view that alcohol use alone increases the risk of HIV infection in gay men. Finding that risk for HIV is highest in men with histories of both alcohol and drug problems suggests that the link between HIV infection and substance use may be mediated by "third variables" that may include personality characteristics and situational factors.