Abstract
BACKGROUND: We evaluated changes in long-term glucocorticoid (GC) use and factors associated with persistent GC use in older adults with late-onset rheumatoid arthritis (LORA). METHODS: Using 20% Medicare data from 2008 to 2017, we identified adults ≥66 years with a new diagnosis of LORA, disease-modifying antirheumatic drug (DMARD) use or at least two rheumatologist visits, and at least 12 months of follow-up data. Older adults were categorized as DMARD-exposed or DMARD-unexposed based on treatment during the 12 months after LORA diagnosis (index date). For each quarter after the index date, long-term GC use was defined as having oral GC prescriptions for at least 30 days with a dose >5 mg/day prednisone equivalent. We compared long-term GC use between quarter (Q)1 and Q4 and performed stratified mixed-effects logistic regression for factors associated with persistent GC use, defined as long-term GC use in Q2 to Q4. RESULTS: The cohort included 15,425 individuals with two-thirds (62.5%) being DMARD-exposed. Between Q1 and Q4, the proportion of older adults on long-term GC declined from 44.1 to 24.9% (∆19.2%) among the DMARD-exposed and from 25.8 to 17.9% (∆7.9%) among the DMARD-unexposed. One year after the index date, 13.5% of the DMARD-exposed and 9.8% of the DMARD-unexposed were persistent GC users. In stratified mixed-effects logistic models, persistent GC use was associated with low-income subsidy status among the DMARD-exposed and with greater comorbidity burden among DMARD-unexposed. CONCLUSION: Long-term GC use declined more among DMARD-exposed than DMARD-unexposed patients. One in seven DMARD-exposed and one in ten DMARD-unexposed have persistent GC use which is associated with financial barriers and multimorbidity that may limit the use of steroid-sparing DMARDs.