Association of Body Mass Index With Clinical Outcomes in Patients With Atrial Fibrillation: A Report From the FANTASIIA Registry

<jats:sec xml:lang="en"> <jats:title>Background</jats:title> <jats:p xml:lang="en"> Obesity and atrial fibrillation ( <jats:styled-content style="fixed-case">AF</jats:styled-content> ) frequently coexist and independently increase mortality. We sought to assess the association between obesity and adverse events in patients receiving oral anticoagulants for <jats:styled-content style="fixed-case">AF</jats:styled-content> . </jats:p> </jats:sec> <jats:sec xml:lang="en"> <jats:title>Methods and Results</jats:title> <jats:p xml:lang="en"> Consecutive <jats:styled-content style="fixed-case">AF</jats:styled-content> outpatients receiving anticoagulant agents (both vitamin K antagonists and direct oral anticoagulants) were recruited into the <jats:styled-content style="fixed-case">FANTASIIA</jats:styled-content> (Atrial fibrillation: influence of the level and type of anticoagulation on the incidence of ischemic and hemorrhagic stroke) registry. This observational, multicenter, and prospective registry of <jats:styled-content style="fixed-case">AF</jats:styled-content> patients analyzes the quality of anticoagulation, incidence of events, and differences between oral anticoagulant therapies. We analyzed baseline patient characteristics according to body mass index, normal: <25 kg/m <jats:sup>2</jats:sup> , overweight: 25–30 kg/m <jats:sup>2</jats:sup> , and obese: ≥30 kg/m <jats:sup>2</jats:sup> ), assessing all‐cause mortality, stroke, major bleeding and major adverse cardiovascular events (a composite of ischemic stroke, myocardial infarction, and total mortality) at 3 years’ follow‐up. In this secondary prespecified substudy, the association of weight on prognosis was evaluated. We recruited 1956 patients (56% men, mean age 73.8±9.4 years): 358 (18.3%) had normal body mass index, 871 (44.5%) were overweight, and 727 (37.2%) were obese. Obese patients were younger ( <jats:italic>P</jats:italic> <0.01) and had more comorbidities. Mean time in the therapeutic range was similar across body mass index categories ( <jats:italic>P</jats:italic> =0.42). After a median follow‐up of 1070 days, 255 patients died (13%), 45 had a stroke (2.3%), 146 a major bleeding episode (7.5%) and 168 a major adverse cardiovascular event (8.6%). Event rates were similar between groups for total mortality ( <jats:italic>P</jats:italic> =0.29), stroke ( <jats:italic>P</jats:italic> =0.90), major bleeding ( <jats:italic>P</jats:italic> =0.31), and major adverse cardiovascular events ( <jats:italic>P</jats:italic> =0.24). On multivariate Cox analysis, body mass index was not independently associated with all‐cause mortality, cardiovascular mortality, stroke, major bleeding, or major adverse cardiovascular events. </jats:p> </jats:sec> <jats:sec xml:lang="en"> <jats:title>Conclusions</jats:title> <jats:p xml:lang="en"> In this prospective cohort of patients anticoagulated for <jats:styled-content style="fixed-case">AF</jats:styled-content> , obesity was highly prevalent and was associated with more comorbidities, but not with poor prognosis. </jats:p> </jats:sec>