Abstract 11520: Cost-Related Medication Nonadherence in Adults with Diabetes Mellitus in the United States

Abstract

Background: Health-related expenditures due to diabetes mellitus (DM) are rising in the US. Medication nonadherence is associated with worse health outcomes, particularly among individuals with DM who require uninterrupted treatment. We sought to determine whether patients with DM in the US report cost-related nonadherence (CRN), a potential consequence of rising drug costs. Methods: We used the National Health Interview Survey (2013-18), a nationally representative study, to identify participants with and without self-reported DM. Participants were considered to have experienced CRN if during the preceding year they reported skipping doses, taking less medication, or delaying filling a prescription to save money. Results: Of the 20,326 participants with DM, a weighted 14% (or 3 million annually) experienced CRN, including 9.5% skipping doses, 9.9% taking less medicine, and 11.8% delaying prescription filling to save money. Compared to those without DM (N=145,186), participants with DM reported a higher prevalence of CRN, with the largest differences being observed among non-elderly adults (Figure). Among non-elderly adults with DM, a weighted 19.4% (or 2.3 million annually) reported CRN. In multivariable logistic regression models, the main drivers of CRN among participants with DM were lack of insurance (OR 4.34, 95% CI 3.49, 5.39), younger age (OR 3.43, 95% CI 2.65, 4.44), low income (OR 1.82, 95% CI 1.58, 2.09), use of insulin (OR 1.19, 95% CI 1.04, 1.35), and unfavorable risk factor profile (OR 1.53, 95% CI 1.21, 1.93) (Table). Conclusion: In the US, 1 in 7 adults with DM reported CRN, and the burden was highest among non-elderly adults. Cost represents a serious barrier for therapy adherence among individuals with DM in the US, particularly among the most vulnerable. Removing financial barriers to accessing medications may improve adherence to essential therapies among individuals with DM, and ultimately improving outcomes.