Disparities in cost-related drug nonadherence under the Affordable Care Act

Abstract

Objective: The Affordable Care Act (ACA), implemented in 2014 in the USA, featured several policies relevant to patients’ out-of-pocket spending for prescription drugs. Our study examined how disparities in cost-related nonadherence (CRN) to prescription drugs changed by race, ethnicity and socioeconomic status after the ACA. Methods: We analysed a nationally representative sample of nonelderly adults aged 18–64 in the 2013–2017 National Health Interview Survey data. The first outcome measure captured individuals who could not afford needed prescription drugs in the past 12 months. Among participants who filled a prescription in the past year, three outcome measures included skipped medication doses, taking less medicine or delaying filling a prescription to save money during that time. Interactions between income, education, and race and ethnicity variables with the post-ACA indicator capture how the ACA affected socioeconomic and racial disparities in CRN, while linear probability regression models adjusted for patient characteristics, region indicators and year dummies. Key finding: Income-based disparities in CRNs narrowed after the ACA. Individuals with incomes below 138% federal poverty level (FPL) had larger reductions in the probability of being unable to afford prescription drugs (−3.83% points), skipping doses (−3.33% points), taking less medication (−3.17% points) or delaying medication fills to save money (−3.68% points) than those with income greater than 400% FPL. Several CRN measures declined more among Hispanics than among non-Hispanic white people. The ACA was also associated with greater CRN reductions among individuals with a high school education. Conclusion: The narrowed disparities in CRN suggest the ACA effectively improved prescription drug adherence by those vulnerable to healthcare cost burdens.