Abstract 10871: The Influence of Body Mass Index on Outcomes in Patients With Atrial Fibrillation: The Obesity Paradox
Introduction: Obesity paradox is hot spots in recent years, obese patients had favorable outcomes in many diseases, but its influence on outcomes in Chinese atrial fibrillation patients has not been investigated. This study is to explore the influence of body mass index (BMI) on one-year follow-up outcomes in Chinese atrial fibrillation patients.
Methods: This study consecutively enrolled atrial fibrillation patients presenting to an emergency department at 19 hospitals in China from 2009 to 2011. A total of 2016 atrial fibrillation patients were enrolled, of which with BMI<18.5 were split into underweight, normal (18.5-24), overweight (24-28), and obese (≥28) categories as per BMI (kg/m2). Multivariate Cox proportional hazards regression was used on all the patients. End points of the analyses were all-cause mortality, cardiovascular mortality.
Results: Mean BMI of all patients was 23.5±3.6 kg/m2. The mortality of one-year all-cause mortality was 13.8%, and 23.2% among underweight, 16.3%, 9.5% and 9.2% among normal weight, overweight and obese category respectively (χ2=30.82, P<0.001). The cardiovascular mortality among the whole patients was 8.3%, among underweight, normal weight, overweight, obese categories were 16.5%, 9.0%, 5.4% and 6.9% respectively(χ2=23.02, P<0.001). On multivariate analysis, as a continuous variable, BMI was not a risk factors for all-cause mortality in established atrial fibrillation (hazard ratio [HR] 0.942; 95% confidence interval [CI] 0.911-0.975; P=0.001); as categorical variable, overweight (HR 0.650; 95%CI 0.484-0.874; P=0.004) and obese (HR 0.596; 95%CI 0.371-0.958; P=0.033) categories were associated with lower all-cause mortality as compared with normal BMI. Overweight (HR 0.668; 95%CI 0.450-0.992; P=0.045) atrial fibrillation patients also had lower cardiovascular mortality as compared with the normal BMI patients.
Conclusion: Our study showed an obesity paradox exists for outcomes in Chinese atrial fibrillation, improved outcomes in atrial fibrillation with increasing BMI. Obesity was not a risk factor for one-year mortality in Chinese atrial fibrillation patients, overweight atrial fibrillation patients appear to have better one-year outcomes than normal BMI patients.
- © 2013 by American Heart Association, Inc.