Parental Education, Midlife Hypertension, and Disparities in Late-Life Cognitive Test Scores: Application of an Equity-Focused Causal Decomposition Approach.

BACKGROUND

Parental education is an important determinant of late-life cognition, but the extent to which intervening on midlife risk factors, such as hypertension, mitigates the impact of early-life factors is unclear. Novel methodological approaches, such as causal decomposition, facilitate the assessment of contributors to health inequities through hypothetical interventions on mediating risk factors.

METHODS

Using harmonized cohorts (Kaiser Healthy Aging and Diverse Life Experiences Study; Study of Healthy Aging in African Americans) and a ratio of mediator probability weights decomposition approach, we quantified disparities in late-life cognitive test scores (semantic memory, executive function, and verbal memory z -scores) across high versus low parental education, and evaluated whether socioeconomic disparities in late-life cognitive test scores would change if the corresponding disparity in midlife hypertension were eliminated.

RESULTS

We observed substantial disparities across levels of parental education in late-life cognitive test scores (eg, =-0.72 95% CI: -0.84 to -0.60 for semantic memory). Hypothetical intervention on midlife hypertension did not substantially reduce disparities in any cognitive domain. Patterns were similar when stratified by race.

CONCLUSIONS

Future work should evaluate other points of intervention across the lifecourse (eg, participant education) to reduce late-life cognitive disparities across levels of parental education.