Factors associated with use of disease modifying agents for rheumatoid arthritis in the National Hospital and Ambulatory Medical Care Survey.

Objective: We examined the treatment patterns among adults with rheumatoid arthritis (RA) and identified factors influencing access to traditional and biological disease modifying antirheumatic drugs (DMARDs).

Methods: We analyzed visits recorded in the National Ambulatory Medical Care Survey from 2005 to 2014 with a RA diagnosis. The primary outcome was DMARD use (traditional and/or biological). We included prescriptions of all RA-related treatments such as traditional and biological DMARDs, glucocorticoids, gold preparations, immunosuppressants, and non-steroidal anti-inflammatory drugs. Covariates in the logistic regression models included age, gender, race/ethnicity, type of health care coverage, provider type, geographic region, and number of comorbidities.

Results: Among 1405 visits with a RA diagnosis, 60.4% (n = 807) were prescribed DMARDs and 23.8% (n = 334) biological DMARDs. In fully adjusted models, females have 1.57 times higher odds of any DMARD use (95% confidence interval (CI): 1.02-2.46). Also, Medicare beneficiaries as compared to privately insured have 2.31 times higher odds of receiving any DMARDs (95% CI: 1.40-3.82), while visits with specialist vs. general physician are 2.38 times more associated with any DMARD use (95% CI: 1.37-4.14). For biological DMARDs, Medicare beneficiaries were at 2.58 times higher odds (95% CI: 1.42-4.70) than privately insured, while visits with specialist are at 3.37 times higher odds than general physician (95% CI: 1.40-8.23).

Conclusion: Visits with a specialist and Medicare beneficiaries were significantly associated with any DMARD or biological DMARD use. Additionally, contrary to prior evidence, race/ethnicity was not associated with any DMARD or biological DMARD use, which may indicate reduction in disparity of treatment access.