Body Mass Index and Adverse Outcomes in Elderly Patients With Atrial Fibrillation: The AMADEUS Trial.

Abstract

Obesity has been associated with increased cardiovascular risk in atrial fibrillation, but little is known in elderly patients with atrial fibrillation. Post hoc analysis of data from the AMADEUS (Evaluating the Use of SR34006 Compared to Warfarin or Acenocoumarol in Patients With Atrial Fibrillation) trial. We studied 1588 elderly patients, who were categorized as normal body mass index (BMI, 18.5-25 kg/m(2); n=515 [32.4%]), overweight (BMI, 25-30 kg/m(2); n=711 [44.8%]), and obese (BMI≥30 kg/m(2); n=362 [22.8%]). There was a significant reduction in the composite outcome of cardiovascular death and stroke/systemic embolism with increasing BMI category, being 5.0%, 3.2%, and 1.5% per 100 patient-years, respectively (P for trend=0.01). Cox proportional hazards analysis found obesity to be associated with a lower risk of the primary composite outcome (hazard ratio, 0.29; 95% confidence interval, 0.11-0.77; P=0.01). In the warfarin arm (n=814), multivariate logistic regression analysis demonstrated that obesity was independently related to higher odds of time in therapeutic range ≥60% (odds ratio, 1.84; 95% confidence interval, 1.21-2.80; P=0.004). Obesity was associated with a lower stroke and mortality rate in elderly anticoagulated atrial fibrillation patients. Obesity was related to good quality anticoagulation control.