Sex differences in the association between education in adulthood and late‐life cognition in the Kaiser Health Aging and Diverse Life Experiences (KHANDLE) Study

Abstract

AbstractBackgroundWhile education is strongly associated with late‐life cognitive level, it is unclear how education after young adulthood is associated with late‐life cognition. This study examines the association between adult education and overall and domain specific cognition in a diverse sample allowing for possible differences in associations by sex. This is important to consider given recent increases in educational opportunities for women.MethodThe Kaiser Healthy Aging and Diverse Life Experiences Study (KHANDLE) enrolled Kaiser Permanente Northern California members age 65+ who completed a Multiphasic Health Checkup (MHC) conducted from 1964‐1996. Among 1,363 KHANDLE participants who reported education attainment at an MHC before age 25, education in adulthood was a binary variable reflecting reporting higher levels of education during KHANDLE interviews than at their first MHC visit after age 25. Executive function, semantic memory and verbal episodic memory were captured through the Spanish and English Neuropsychological Assessment Scales (SENAS) during KHANDLE baseline interviews and z‐standardized. Linear regressions estimated the association between education in adulthood and domain‐specific late‐life cognition adjusting for age at MHC, age at KHANDLE, sex, race/ethnicity, and educational attainment at MHC. Stratified models and interaction terms tested for possible sex differences in associations.ResultWomen were more likely than men to have ≤ HS at their MCH (33% vs 20%; chi‐square p‐value=<0.0001) and to receive additional education during adulthood (37% vs 27%; chi‐square p‐value=<0.0001). Among recipients of adult education, 50% had ≤ HS at their MCH and at the KHANDLE interview 25% completed HS or trade school, 18% completed college, and 24% completed graduate school. Education during adulthood was associated with executive function (β=0.18, 95% CI: 0.07, 0.28) but not semantic memory (β=0.09, 95% CI: ‐0.02, 0.19) nor verbal episodic memory (β=0.06, 95% CI: ‐0.05, 0.18). The association between adulthood education and executive function was stronger among women than men (women: β=0.19, 95% CI: 0.06, 0.32; men β=0.12, 95% CI: ‐0.07, 0.32; executive function*female interaction term p‐value=0.04).ConclusionEducation during adulthood was associated with better executive function among women. Additional research is needed to assess if education during adulthood is associated with cognition and cognitive decline in late‐life.