Optimal stroke prevention strategies for patients with atrial fibrillation (AF) who experience a major bleed are poorly defined. We sought to estimate the effectiveness and safety of oral anticoagulation (OAC) represcription after an OAC contraindication.
TREAT-AF is a retrospective cohort study of patients with newly diagnosed AF (2004-2012), treated in the Veterans Health Administration. From this cohort, we identified patients with a contraindication to OAC after AF diagnoses, defined as incident intracranial bleeding, non-intracranial bleeding requiring hospitalization, or unrepaired cerebral aneurysm or aortic dissection. We used multivariate Cox proportional hazards to estimate the association of OAC prescription in the 90 days following OAC contraindication to ischemic stroke and rebleeding.
Among 167,190 patients with newly diagnosed AF (70 ± 11 years, 1.7% female, CHADS-VASc 2.7 ± 1.7), 19,285 patients (11.5%) had an incident bleed (n = 18,342) or an unrepaired cerebral aneurysm or aortic dissection (n = 943). For OAC-contraindicated patients with a CHADS-VASc ≥2 (N = 16,194), OAC was represcribed in 4075 patients (25%) and was associated with a higher risk of non-intracranial bleeding (HR 1.49; 95% CI 1.37-1.61; p < 0.0001) but no difference in intracranial bleeding. There was a trend toward decreased stroke risk (HR 0.85; 95% CI 0.71-1.02; p 0.09).
Development of contraindication to OAC after diagnosis of AF is common (11.5%), with most events requiring hospitalization. OAC reinitiation was associated with non-intracranial bleeding risk, with a trend toward reduced stroke risk. These data suggest that stroke prevention approaches after major bleeding events could be beneficial if bleeding risk can be successfully mitigated.