Association of cerebral microbleeds with mortality in stroke patients having atrial fibrillation

OBJECTIVES:We investigated the association of cerebral microbleeds (CMBs) with long-term mortality in patients with nonvalvular atrial fibrillation (NVAF) according to burden and distribution of CMBs. METHODS:This was a retrospective, hospital-based, observational study. In total, 504 consecutive ischemic stroke patients with NVAF who underwent brain T2-weighted, gradient-recalled echo MRI were included. Data for the date and causes of death were based on the death certificates from the Korean National Statistical Office. We determined the association of the presence, burden, and distribution of CMBs with mortality from all-cause, ischemic heart disease, ischemic stroke, and hemorrhagic stroke. RESULTS:CMBs were found in 30.7% of patients (155/504). During a median follow-up of 2.5 years, 176 patients (34.9%) died (ischemic stroke, 81; hemorrhagic stroke, 12; ischemic heart disease, 32). Patients with CMBs died more frequently than those without (41.9% vs 31.8%, p = 0.028). After adjusting for age, sex, and other significant variables, the presence of multiple (≥5) CMBs was as an independent predictor for all-cause (hazard ratio [HR]1.99) and ischemic stroke (HR3.39) mortality. Patients with strictly lobar CMBs had an increased risk of hemorrhagic stroke mortality (HR5.91). CONCLUSIONS:The presence and burden of CMBs were associated with increased mortality in stroke patients with NVAF. Patients with lobar CMBs were at increased risk of death due to hemorrhagic stroke. The diagnosis of CMBs is of value in predicting long-term prognosis in stroke patients with NVAF.