Trajectories of cognitive functioning in later life: Disparities by race/ethnicity, educational attainment, sex, and multimorbidity combinations

Evaluating multimorbidity combinations, racial/ethnic background, educational attainment, and sex associations with age-related cognitive changes is critical to clarifying the health, sociodemographic, and socioeconomic mechanisms associated with cognitive function in later life. Data from the 2011–2018 National Health and Aging Trends Study for respondents aged 65 years and older (N = 10,548, mean age = 77.5) were analyzed using linear mixed effect models. Racial/ethnic differences (mutually-exclusive groups: non-Latino White, non-Latino Black, and Latino) in cognitive trajectories and significant interactions with sex and education (<high school, high school, some college, and ≥ college degree) were evaluated. Models included sex, education, ever covered by Medicaid, coupled status, waist-height ratio, study cohort, and chronic disease category (no diseases; one disease; advanced cardiovascular multimorbidity; metabolic multimorbidity; advanced cardiovascular-metabolic multimorbidity; and neither advanced cardiovascular nor metabolic multimorbidity). In covariate-adjusted models, Black (b = −1.31, 95% CI: 1.74,-0.89) and Latino (b = −0.83, 95% CI: 1.58,-0.07) respondents had lower cognitive scores at age 65 and steeper declines with age (b = −0.08, 95% CI: −0.15,-0.01; b = −0.20, 95% CI: 0.34,-0.05, respectively) compared with White respondents. Cognitive scores were lower among respondents with advanced cardiovascular (b = −0.28, 95% CI: 0.54,-0.01) and advanced cardiovascular-metabolic (b = −0.56, 95% CI: 0.86,-0.27) multimorbidity compared with respondents with none of the chronic diseases of interest. In interaction models, protective associations by female sex and higher education were not observed among minority racial/ethnic groups. It is important to develop interventions to postpone cognitive decline among older Black and Latino adults.