P4778Effectiveness and safety of rivaroxaban versus warfarin in nonvalvular atrial fibrillation patients with coronary or peripheral artery disease

Background

The efficacy and safety of rivaroxaban use for the prevention of major thrombotic vascular events (MTVEs) has been demonstrated in randomized trials of nonvalvular atrial fibrillation (NVAF), coronary artery disease (CAD) and peripheral artery disease (PAD) patients.

Purpose

To assess the effectiveness and safety of rivaroxaban versus warfarin in preventing MTVEs in NVAF patients with concomitant CAD and/or PAD in routine practice.

Methods

Using MarketScan data from 1/2012–12/2017, we identified oral anticoagulant (OAC)-naïve NVAF patients with comorbid CAD and/or PAD and ≥12-months of insurance coverage before OAC initiation. Differences in baseline covariates between cohorts were adjusted using inverse probability-of-treatment weights based on propensity-scores (standardized differences <0.1 achieved for all covariates after adjustment). The primary effectiveness endpoint was the composite of any MTVE including ischemic stroke, myocardial infarction or adverse limb event (revascularization or amputation). The primary safety endpoint was major bleeding defined using the Cunningham algorithm. Patients were followed until a MTVE, discontinuation or switch of index OAC, insurance disenrollment or end-of-data availability. Hazard ratios (HRs) and 95% confidence intervals (CIs) comparing the cohorts were calculated using Cox regression.

Results

We identified 3,257 rivaroxaban (30.4% received a reduced dose) and 5,046 warfarin users with NVAF and comorbid CAD and/or PAD. Median (25%-75% range) age was 74 (65–81) years, CHA2DS2-VASc score was 3 (2–4). Rivaroxaban was associated with a 32% (95% CI=8–50%) reduction in the composite of any MTVE (Figure). No significant difference in major bleeding was observed (HR=1.13, 95% CI=0.84–1.52).

Figure 1. Event Rates and Hazard Ratios

Conclusions

In patients with NVAF and comorbid CAD and/or PAD treated in routine practice, rivaroxaban use appears to reduce patients' risk of MTVEs compared to warfarin, without increasing their risk of major bleeding. This study lends further support to RCT findings that suggest rivaroxaban is effective in preventing major events in multiple vascular beds.

Acknowledgement/Funding

Bayer AG, Berlin, Germany