Abatacept vs TNFi reduces cardiovascular risk in RA patients

Initiation of abatacept (ABA) vs tumour necrosis factor inhibitors (TNFi) leads to a 20-percent reduction in risk of cardiovascular disease (CVD) in a large cohort of insured patients with rheumatoid arthritis (RA), a US study has shown.

Of the 6,102 propensity score (PS)-matched pairs of ABA and TNFi initiators from Medicare and 6,934 pairs from MarketScan, 35.3 percent in the former and 14.0 percent in the latter had baseline CVD. In the overall ABA vs TNFi group, the hazard ratio (HR) for composite CVD was 0.67 (95 percent CI, 0.55–0.81) in Medicare and 1.08 (0.83–1.41) in MarketScan (combined HR, 0.79; 0.67–0.92).

The HRs among patients with baseline CVD were 0.71 (0.55–0.92) and 1.02 (0.68–1.51) in Medicare and MarketScan, respectively (combined HR, 0.79; 0.64–0.98).

“While this observational study is subject to potential residual confounding, our results were consistent in patients with baseline CVD,” the authors said.

To assess the cardiovascular safety of ABA vs TNFi in RA patients with and without underlying CVD, the authors identified RA patients who initiated ABA or TNFi using data from two large US insurance claims databases: Medicare (2008–2013) and Truven MarketScan (2006–2015).

Stratified by baseline CVD, ABA initiators were PS-matched to TNFi initiators to control for >60 covariates. The authors used Cox proportional hazards regression to estimate HR for a composite endpoint of CVD including myocardial infarction, stroke/transient ischaemic stroke or coronary revascularization in the PS-matched cohorts. An inverse variance-weighted fixed-effects model was used to combine HR from two databases.