Lifecourse socioeconomic status and subjective cognitive decline among diverse older adults.

OBJECTIVES

Lifecourse socioeconomic conditions are important determinants of age-related cognitive decline and dementia. We extend this research by examining whether these associations hold for subjective cognitive decline (SCD), an early marker that may reflect dementia risk across socioeconomic contexts.

METHODS

In 2 multiethnic older-adult cohorts of long-term Kaiser Permanente Northern California members without prior dementia, we constructed dichotomous measures of financial, social, and cultural capital in childhood and late life. SCD was measured using the psychometrically validated Everyday Cognition 12-item scale (ECog-12). Generalized linear models estimated associations of each lifecourse socioeconomic status (SES) measure with SCD in the entire sample and stratified by sex/gender and race/ethnicity. Causal mediation analyses explored whether depressive symptoms (PROMIS Depression) mediated findings. All models adjusted for age, and moderation models adjusted for sex/gender or race/ethnicity.

RESULTS

Low childhood (b = 0.098, 95% CI: 0.056, 0.140) and late-life (b = 0.080, 95% CI: 0.051, 0.110) financial capital, low childhood (b = 0.054, 95% CI: 0.023, 0.085) and late-life social capital (b = 0.062, 95% CI: 0.018, 0.107), and low late-life (b = 0.068, 95% CI: 0.030, 0.106) cultural capital were each independently associated with greater SCD. Low late-life cultural capital had the strongest negative impact among Black participants (b = 0.143, 95% CI: 0.085, 0.202). Depressive symptoms partially mediated associations of childhood and late-life financial and social capital with SCD, accounting for approximately 34%-64% of the associations.

DISCUSSION: Multiple aspects of lifecourse SES contribute to SCD, with variation by sex/gender and race/ethnicity in lifecourse cultural capital. Depression may be a key pathway linking lifecourse SES disadvantage to SCD.