Access and Cost-Related Nonadherence to Prescription Medications Among Lupus Patients and Controls: The Michigan Lupus Epidemiology and Surveillance Program.

Abstract

Medication access and adherence are important determinants of health outcomes. We investigated factors associated with access and cost-related nonadherence to prescriptions in a population-based cohort of systemic lupus erythematosus (SLE) patients and controls. Detailed sociodemographic and prescription data were collected by structured interview in 2014-2015 from participants in the Michigan Lupus Epidemiology and Surveillance (MILES) cohort. We compared access between cases and frequency-matched controls and examined associated factors in separate multivariable logistic regression models. A total of 654 participants (462 SLE patients, 192 controls) completed the baseline visit; 584 (89%) were female, 285 (44%) were Black, and the mean age was 53 years. SLE patients and controls reported similar frequencies of being unable to access prescribed medications (12.1% versus 9.4%, respectively; P was not significant). SLE patients were twice as likely as controls to report cost-related prescription nonadherence in the preceding 12 months to save money (21.7% versus 10.4%; P = 0.001) but were also more likely to ask their doctor for lower cost alternatives (23.8% versus 15.6%; P = 0.02). Disparities were found in association with income, race, and health insurance status, but the main findings persisted after adjusting for these and other variables in multivariable models. SLE patients were more likely than controls from the general population to report cost-related prescription nonadherence, including skipping doses, taking less medicine, and delaying filling prescriptions; yet, <1 in 4 patients asked providers for lower cost medications. Consideration of medication costs in patient decision-making could provide a meaningful avenue for improving access and adherence to medications.