Kidney, limb and ophthalmic complications, and death in patients with nonvalvular atrial fibrillation and type 2 diabetes prescribed rivaroxaban or warfarin: an electronic health record analysis

BACKGROUND: Patients with nonvalvular atrial fibrillation (NVAF) and type 2 diabetes are at risk of kidney, limb, and ophthalmic complications. We evaluated the rate of these complications and death in patients with NVAF and type 2 diabetes prescribed rivaroxaban or warfarin. METHODS: We analyzed Optum de-Identified electronic health record (EHR) data from 11/2010-12/2019. We included adults with NVAF and T2D newly initiated on rivaroxaban or warfarin with ≥12 months of prior EHR activity. Patients with another indication for anticoagulation, valve disease, history of end-stage renal disease, major adverse limb events (MALE), diabetic retinopathy or pregnancy were excluded. We evaluated the incidence rate of developing a composite outcome of >40% decrease in estimated glomerular filtration incidence rate (eGFR) from baseline, eGFR < 15 mL/minute/1.73 m2, need for dialysis or kidney transplant, MALE, diabetic retinopathy or death. Overlap weighting was used to balance baseline characteristics between cohorts while preserving sample size. Hazard ratios with 95% confidence intervals were calculated using propensity score-overlap weighted Cox regression. RESULTS: We included 24,912 rivaroxaban and 58,270 warfarin users. The mean ± standard deviation (SD) CHA2DS2VASc score was 4.3 ± 1.5 and modified HASBLED score was 1.5 ± 0.8. Thirty percent of rivaroxaban patients were started on 15 mg once daily, with the rest prescribed 20 mg once daily. Warfarin patients had a mean time in therapeutic range of 47 ± 28%. Patients were followed for a mean of 2.89 ± 1.95 years. Rivaroxaban was associated with a reduced hazard of the composite outcome (HR = 0.93, 95%CI = 0.91-0.95; absolute risk reduction = 1.97 events per 1000 patient-years; number needed-to-treat = 51) versus warfarin. Rivaroxaban was also associated with significant reductions in the relative hazard of > 40% decrease in eGFR from baseline (HR = 0.96), need for dialysis or renal transplant (HR = 0.81), and limb revascularization or major amputation (HR = 0.85). Death occurred at a lower incidence rate with rivaroxaban (HR = 0.92, 95%CI = 0.89-0.95). CONCLUSIONS: NCT04509193.