OBJECTIVES: Estimate the burden of Rheumatoid Arthritis (RA) in the US Medicare population by comparing comorbidities and healthcare resource utilization (HRU) among Medicare RA and non-RA patients.  METHODS: Retrospective study using Medicare data (01JAN2011-31DEC2013) among RA patients aged ≥65 years with ≥2 diagnostic medical claims for RA (International Classification of Diseases, Ninth Revision, Clinical Modification [ICD-9-CM] code: 714.xx) ≥2 months apart during the identification period (01JAN2012-31DEC2012) and matched 1:1 with non-RA control patients based on demographics. The earliest RA claim date was considered the index date for RA patients. The index date for control patients was assigned to match the case RA patients. Patients were required to have continuous health plan enrollment for ≥12 months pre-index (baseline period) and post-index date (follow-up period). Demographic and clinical characteristics were compared among the matched patients during the baseline period, and HRU was compared during the follow-up period.  RESULTS: Matched cohorts included 276,150 patients (RA: 138,075; non-RA: 138,075), average age 76 years, 78% were women, 86% Caucasian, 41% resided in the South US region, and 47% had a high socioeconomic status score. RA patients had a significantly higher comorbidity burden compared to non-RA patients, including a higher Charlson Comorbidity Index score (1.9 vs. 1.0, p<0.0001), severity index for rheumatoid arthritis score (5.1 vs. 0.4, p<0.0001), chronic disease score (8.3 vs. 5.6, p<0.0001), and more individual comorbidities (malignant neoplasms, diseases of skin, digestive system, nervous system, respiratory system, genitourinary system, circulatory system, and connective tissue system [all p<0.0001]). RA patients had significantly more follow-up inpatient visits (0.63 vs. 0.33, p<0.0001), outpatient hospital visits (6.4 vs. 4.6, p<0.0001), outpatient office visits (21 vs. 13, p<0.0001), and pharmacy visits (31 vs. 23, p<0.0001) compared to non-RA patients.  CONCLUSIONS: RA patients are more medically complex than non-RA populations resulting in higher healthcare costs.