Utilization and costs of medical services and prescription medications for rheumatoid arthritis among recipients covered by a state medicaid program: A retrospective, cross-sectional, descriptive, database analysis

Abstract

Background: Rheumatoid arthritis (RA) is a chronic autoimmune disorder characterized by inflammation of synovial tissues that leads to joint swelling, stiffness and pain, and progressive joint destruction. There is currently limited information about demographic differences in the prevalence of RA and the utilization and costs of RA-related prescription medications and medical services among low-income populations. Objectives: This study assessed the prevalence of RA and the utilization and costs of RA-related medical services and prescription medications among recipients enrolled in a state Medicaid program. Methods: A retrospective, cross-sectional, descriptive analysis of West Virginia (WV) Medicaid fee-for-service administrative claims data was conducted. Medical services claims for recipients aged between 15 and 64 years with a primary diagnosis code for RA during the calendar year 2003 were extracted. Unique recipient numbers obtained from these claims were used to extract the corresponding prescription claims. Prevalence and health care use rates were calculated by demographic categories. Costs were reported from the perspective of WV Medicaid. Results: A total of 143,211 recipients aged between 15 and 64 years received WV Medicaid benefits. Among these, 1157 recipients (0.81%) had ≥ 1 medical service claim (hospitalization, emergency department visit, or office visit) with a primary diagnosis of RA. The mean (SD) age of the sample was 47 (11.1) years. The highest rates of RA by age, sex, and race occurred among recipients aged 45 to 64 years (16.4:1000), females (10.1:1000), and whites (8.2:1000). Office visits accounted for the majority of medical services visits and costs. Among the sample, 67.8% had ≥1 prescription claim for a narcotic analgesic, 58.8% for an NSAID, 48.3% for an oral steroid, 40.1% for a disease-modifying antirheumatic drug, and 12.4% for a biologic agent. Medicaid paid a mean of $2379 per recipient for RA-related health care services. Prescription claims accounted for 74.6% of the total cost of RA care. Biologic agents accounted for the largest proportion (54.1% ) of prescription costs. Conclusions: The prevalence of RA and rates of health care services utilization for RA among recipients of WV Medicaid differed with regard to demographic characteristics. Utilization of RA-related prescription medication among recipients varied by pharmacotherapy class. This study presents baseline information that might be used as a model for future surveillance RA studies using payer administrative datasets.