Discrimination, Mediating Psychosocial or Economic Factors, and Antihypertensive Treatment: A 4-Way Decomposition Analysis in the Health and Retirement Study.

Untested psychosocial or economic factors mediate associations between perceived discrimination and suboptimal antihypertensive therapy. This study included two waves of data from the Health and Retirement Study participants with self-reported hypertension (N=8557, 73% Non-Hispanic White, 17% Non-Hispanic Black, and 10% Hispanic/Latino) over four years (2008-2014). Our primary exposures were frequency of experiencing discrimination in everyday life or across seven lifetime circumstances. Candidate mediators were self-reported depressive symptoms, subjective social standing, and household wealth. We evaluated with causal mediation methods the interactive and mediating associations between each discrimination measure and reported antihypertensive use at the subsequent wave. In unmediated analyses, everyday (OR; 95% CI: 0.86; 0.78, 0.95) as well as lifetime discrimination (OR; 95% CI: 0.91; 0.85, 0.98) were associated with a lower likelihood of antihypertensive use. Discrimination was associated with lower wealth, greater depressive symptoms, and decreased subjective social standing. Estimates for associations due to neither interaction nor mediation resembled unmediated associations for most discrimination-mediator combinations. Lifetime discrimination was indirectly associated with reduced antihypertensive use via depressive symptomology (OR; 95% CI: 0.99; 0.98, 1.00). In conclusion, the impact of lifetime discrimination on the underuse of antihypertensive therapy appears partially mediated by depressive symptoms.