Cost-Related Medication Behaviors for Patients With and Without Systemic Autoimmune Rheumatic Diseases.

Objective: Medication nonadherence challenges the management of systemic autoimmune rheumatic diseases (SARDs). We investigated cost-related medication behaviors among patients with SARDs, and compared them to those of patients without SARDs, in a large diverse cohort across the United States.

Methods: As part of the All of Us (version 7), a nationwide diverse adult cohort with linked electronic health records begun in 2017, participants completed questionnaires concerning cost-related medication behaviors. Chi-square tests compared responses between patients with SARDs, by disease and medication type, and to those without SARDs. Logistic regression analyses were used to calculate odds ratios (95% confidence intervals [CIs]).

Results: We analyzed data from 3,997 patients with SARDs and 73,990 participants without SARDs. After adjustment, patients with versus without SARDs had 1.56 times increased odds of reporting unaffordability of prescription medicines (95% CI 1.43-1.70), 1.43 times increased odds of cost-related medication nonadherence (95% CI 1.31-1.56), and 1.23 times increased odds of using cost-reducing strategies (95% CI 1.14-1.32). Patients with SARDs who reported unaffordability were 16.5% less likely to receive a disease-modifying drug (95% CI 0.70-0.99) but 18.1% more likely to receive glucocorticoids (95% CI 0.99-1.42). In addition, unaffordability of prescription medicines was likely to have 1.27 times increased odds of one to two emergency room visits per year (95% CI 1.03-1.57) and 1.38-fold increased odds of three or more emergency room visits per year (95% CI 0.96-1.99).

Conclusion: In this large diverse cohort, patients with versus without SARDs had more self-reported cost-related medication behaviors, and those who reported medication unaffordability received fewer disease-modifying drugs and had more emergency room visits.