Abstract
BACKGROUND: Fixed-dose combination (FDC) antihypertensives combine two or more agents. Compared with non-FDC antihypertensives of multiple classes (multi-pill therapy), combination-pill therapy using FDC antihypertensives may improve hypertension control. However, combination-pill therapy remains low. OBJECTIVES: This study aims to assess: 1) the association between combination-pill therapy and medication adherence, health care utilization, and costs; and 2) the potential to mitigate racial and ethnic differences in medication adherence. METHODS: A retrospective cohort analysis was conducted using the 2017-2021 Merative MarketScan Medicaid database. The study sample included adults aged 18 to 64 years with hypertension, continuously enrolled 1 year before and after a random index date of prescription. The propensity score overlap weighting method was used to balance characteristics between individuals using combination- and multi-pill therapy. Logistic models were used for medication adherence (defined as medication possession ratio [MPR] ≥80%), linear models for continuous MPRs, negative binomial models for health care utilization, and generalized linear models for costs. RESULTS: Compared with multi-pill therapy, combination-pill therapy was associated with higher medication adherence (3.17 in MPR; 95% CI: 2.79-3.55), fewer hypertension-related emergency department visits (220 per 1,000 individuals; 95% CI: -235 to -204), fewer hospitalizations (153 per 1,000 individuals, 95% CI: -160 to -146), and lower costs ($2,862 per person, 95% CI: -$3,035 to -$2,689). However, differences in medication adherence persisted, with non-Hispanic Black adults demonstrating lower adherence than non-Hispanic White adults. CONCLUSIONS: Combination-pill therapy could improve hypertension management and save costs for the Medicaid program and beneficiaries. However, persistent racial and ethnic differences in adherence highlight the need for tailored interventions.