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; multimorbidity; multimorbidity; multimorbidity; and 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 (b = -0.28, 95% CI: 0.54,-0.01) and (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.