Treatment of rheumatoid arthritis in the Medicare Current Beneficiary Survey.

INTRODUCTION: Numerous studies across different health systems have documented that many patients with rheumatoid arthritis (RA) do not receive disease-modifying anti-rheumatic drugs (DMARDs). Relatively little is known about correlates of DMARD use and whether there are socioeconomic and demographic disparities. We examined DMARD use during 2001-2006 in the Medicare Current Beneficiary Survey (MCBS), a longitudinal US survey of randomly selected Medicare beneficiaries. METHODS: Participants in MCBS with RA were included in the analyses, and DMARD use was based on an in-home assessment of all medications. Variables included as potential correlates of DMARD use in weighted regression models included race/ethnicity, insurance, income, education, rheumatology visit, region, age, gender, comorbidity index, and calendar year. RESULTS: The cohort consisted of 509 MCBS participants with a diagnosis code for RA. Their median age was 70 years, 72% were female, and 24% saw a rheumatologist. Rates of DMARD use ranged from 37% among those < 75 years of age to 25% of those age 75-84 and 4% of those age 85 and older. The multivariable adjusted predictors of DMARD use include: visit with a rheumatologist in the prior year (odds ratio, OR, 7.74, 95% confidence interval, CI, 5.37-11.1) and older patient age (compared with < 75 years, ages 75-84 OR 0.58, 95% CI 0.37 - 0.92 and 85 and over OR 0.09, 95% CI 0.02 - 0.31). In those without a rheumatology visit, lower income and older age were associated with a significantly reduced probability of DMARD use; no association of DMARD use with income or age was observed for subjects seen by rheumatologists. Race and ethnicity were not significantly associated with receipt of DMARDs. CONCLUSIONS: Among individuals not seeing rheumatologists, lower income and older age were associated with a reduced probability of DMARD use. (March 18, 2013)