Cardiovascular (CV) Risk after Initiation of Abatacept versus TNF Inhibitors in Rheumatoid Arthritis Patients with and without Baseline CV Disease

Objective. To evaluate the cardiovascular safety of abatacept (ABA) versus tumor necrosis factor inhibitors (TNFi) in rheumatoid arthritis (RA) patients with and without underlying cardiovascular disease (CVD). Methods. We identified RA patients with and without baseline CVD who initiated ABA or TNFi by using data from 2 large US insurance claims databases: Medicare (2008-2013) and Truven MarketScan (2006-2015). After stratifying by baseline CVD, ABA initiators were 1:1 propensity score (PS) matched to TNFi initiators to control for > 60 baseline covariates. Cox proportional hazards regression estimated the FIR and 95% CI for a composite endpoint of CVD including myocardial infarction, stroke/transient ischemic stroke, or coronary revascularization in the PS-matched cohorts. FIR from 2 databases were combined through an inverse variance-weighted fixed-effects model. Results. We included 6102 PS-matched pairs of ABA and TNFi initiators from Medicare and 6934 pairs from MarketScan. Of these, 353% in Medicare and 14.0% in MarketScan had baseline CVD. HR (95% CI) for composite CVD in the overall ABA group versus TNFi was 0.67 (0.55-0.81) in Medicare and 1.08 (0.83-1.41) in MarketScan with the combined HR of 0.79 (0.67-0.92). Among patients with baseline CVD, the HR (95% CI) was 0.71 (055-0.92) in Medicare and 1.02 (0.68-151) in MarketScan, with the combined HR of 0.79 (0.64-0.98). Conclusion. In this large cohort of publicly or privately insured patients with RA in the United States, ABA was associated with a 20% reduced risk of CVD versus TNFi. While this observational study is subject to potential residual confounding, our results were consistent in patients with baseline CVD.