The aim of this study was to use real-world data to evaluate potential interactions between age, treatment, and the risk of developing four adverse events (AEs) common in the elderly: congestive heart failure, serious infections, non-melanoma skin cancer, and interstitial lung disease. These AEs were identified as important in a prior age-based analysis (≤ 65 vs > 65 years) of etanercept- or placebo-treated patients with rheumatoid arthritis (RA) in controlled clinical trials.
Real-world data (1 January 2013 to 31 January 2018) were obtained from the IBM Watson Health MarketScan® Database. Patients were included if aged ≥ 18 years, enrolled for ≥ 1 year prior to RA diagnosis, and without any of the four AEs of interest prior to RA diagnosis or between RA diagnosis and first etanercept exposure. Logistic regression analysis was applied following propensity matching of patients receiving or not receiving etanercept based on age at diagnosis, age status at the beginning of observation (> 65 years or not), sex, geographic region, and follow-up duration.
The overall cohort comprised 403,689 patients. The absolute risk of each of the four AEs increased with age. In propensity-matched cohorts, etanercept was associated with significantly higher odds of developing each of the four AEs (p < 0.001 for all). However, the relative risk of experiencing the four AEs in patients who received etanercept versus those who did not was similar between patients ≤ 65 years of age and those > 65 years of age.
In patients with RA, the relative increase in etanercept-associated risk of experiencing congestive heart failure, serious infection, non-melanoma skin cancer, or interstitial lung disease was similar between elderly and non-elderly.