According to the results of the study, compared to rivaroxaban, apixaban was associated with both a decreased risk of non-ICH hemorrhage (sHR=0.560, 95% CI=0.423–0.741), but not ICH, and rVTE (sHR = 0.802, 95%CI = 0.651–0.988) risk. This was primarily in emergent readmissions (sHR[emergent hemorrhage] = 0.515, 95%, CI=0.372–0.711; sHR[emergent rVTE]=0.636, 95%, CI=0.488–0.830), the researchers noted.
The study identified several contributors to emergent hemorrhage in apixaban-treated patients; including older age (sHR = 1.025, 95%, CI = 1.011–1.039), female sex (sHR = 1.662, 95% CI, 1.252–2.207), prior prescription antiplatelet therapy (sHR=1.591, 95% CI, 1.130–2.241), and complicated hypertension (sHR=1.936, 95% CI, 1.134–3.307).
In terms of limitations, the research team noted the standard limitations associated with retrospective data-driven investigations; including potential selection bias, missing variables, and miscoded or missing data. Moreover, all diagnoses and prescriptions they analyzed were identified based on standardized coding systems, and clinical notes are not available to verify billed claims.“Apixaban was associated with lower overall risk of hemorrhage and readmission for rVTE compared to rivaroxaban when treating patients with VTE without atrial fibrillation, even when excluding events taking place during a fixed three-week loading phase. These differences were derived after adjusting for outpatient mortality as a competing risk and translated into reductions in the number of emergency readmissions. Complicated hypertension and pulmonary disease, among other risk factors, were major contributors to hemorrhage risk on apixaban. In a risk-stratification exercise predicting hemorrhage risk at start of apixaban, we identified a subset of patients with a three-fold increase in bleeding risk who may benefit from closer monitoring and more frequent assessment of the risks and benefits of anticoagulation,” the researchers concluded.