Race and sex differences in lifespan glycemic status and midlife cognitive function: The Bogalusa Heart Study

Abstract

AbstractBackgroundThe association between early‐life glycemic control (during adolescence and young‐adulthood) and both cognition and risk of AD is not well understood. Furthermore, African Americans (AA) are underrepresented in aging research and disproportionally at higher risk for diseases related to glycemic control (Chow et al., 2012). This study assessed race and sex differences in the association between early‐life glycemic control and midlife cognitive function in a biracial, semi‐rural, Deep Southern population‐based epidemiological cohort.MethodThe Bogalusa Heart Study has followed participants from childhood to adulthood since 1973. Glycemic control measures including fasting insulin and glucose, and HOMA‐IR, were collected at roughly biannual visits from 1973 to today and cognitive measures were collected between 2013‐2016. Cognitive measures (n = 1295) included memory, executive function (EF), and global cognition. Glycemic control variables were averaged within specific age epochs (<20 (adolescent), 21‐40 (early adulthood) and >40 (adulthood). Linear regression models had metabolic measures as predictors and cognitive measures as outcomes. Models were run within age and race specific subgroups including sex, race, and education as covariates.ResultAmong women, greater levels of each glycemic predictor within adolescent and early‐adulthood epochs were associated with poorer memory and EF (Average Est. ‐0.018, p ≤ 0.037), and greater fasting glucose within the adolescent epoch was associated with poorer global cognition (Average Est. ‐0.061, p = 0.021). Greater HOMA‐IR and insulin levels within the adolescent epoch were associated with greater memory among men (Average Est. 0.040, p ≤ 0.020). Among AA, greater fasting glucose was associated with lesser EF performance within each epoch (Average Est. ‐0.006, p ≤ 0.037). Greater HOMA‐IR and insulin levels within early‐adulthood and >40 epochs were associated with greater memory for AA, and greater EF among whites (Average Est. 0.013, p ≤ 0.040 (AA), 0.029, p ≤ 0.025 (white)).ConclusionPoorer early to mid‐life glycemic control is associated with poorer EF and memory for women, better memory for men and AA, poorer EF for AA, and better EF for whites. Race and sex differences in the relationship between lifespan glycemic exposures and cognition decades later are pronounced and could reflect disparities in health‐related exposures throughout the lifespan.