Cost-related medication nonadherence in older patients with rheumatoid arthritis.

OBJECTIVE: Economic access to costly medications including biologic agents can be challenging. Our objective was to examine whether patients with rheumatoid arthritis (RA) are at particular risk for cost-related medication nonadherence (CRN) and spending less on basic needs.
METHODS: We identified a nationally representative sample of older adults with RA (n = 1100) in the Medicare Current Beneficiary Survey (2004-2008) and compared them to older adults with other morbidities categorized by chronic disease count: 0 (n = 5898), 1-2 (n = 30,538), and ≥ 3 (n = 34,837). We compared annual rates of self-reported CRN (skipping or reducing medication doses or not obtaining prescriptions because of cost) as well as spending less on basic needs to afford medications and tested for differences using survey-weighted logistic regression analyses adjusted for demographic characteristics, health status, and prescription drug coverage.
RESULTS: In the RA sample, the unadjusted weighted prevalence of CRN ranged from 20.7% in 2004 to 18.4% in 2008 as compared to 18.5% and 11.9%, respectively, in patients with 3 or more non-RA conditions. In adjusted analyses, having RA was associated with a 3.5-fold increase in the risk of CRN (OR 3.52, 95% CI 2.63-4.71) and almost a 2.5-fold risk of spending less on basic needs (OR 2.41, 95% CI 1.78-3.25) as compared to those without a chronic condition.
CONCLUSION: Patients with RA experience a high prevalence of CRN and forgoing of basic needs, more than do older adults with multiple other chronic conditions. The situation did not improve during a period of policy change aimed at alleviating high drug costs.