Lee SR, Choi EK, Jung JH, et al. - In Asian patients with atrial fibrillation taking oral anticoagulants, researchers determined if there is a correlation between body mass index (BMI) and clinical outcomes. New oral anticoagulant users were identified among non-valvular atrial fibrillation patients with BMI information between January 2015 and December 2017 using the Korean National Health Insurance database. In total, 43,173 patients were involved across the following BMI categories (kg/m²): underweight (< 18.5) in 3%, normal (18.5 to < 23) in 28%, overweight (23 to < 25) in 24%, obese I (25 to < 30) in 39%, and obese II (≥ 30) in 6%. A reduced risk of ischemic stroke, major bleeding, as well as better survival were independently correlated with a higher BMI. There was a higher risk of all-cause death and composite clinical outcome in underweight patients. Optimal BMI should be defined and managed according to an integrated care pathway for patients with atrial fibrillation.