Abstract 15799: Body Mass Index Modulates Symptomatic Atrial Fibrillation Burden
Introduction: Atrial fibrillation (AF) is the most common sustained arrhythmia and is associated with significant morbidity and increased mortality. Approximately fifty percent of patients have AF-related symptoms and require rhythm control therapy with antiarrhythmic drugs (AADs) or cathether ablation. Obesity is increasingly recognized as an important risk factor for the development of AF.
Hypothesis: We assessed the hypothesis that body mass index (BMI) modulates AF symptom severity.
Methods: Cross-sectional data was collected from 1429 patients in the Vanderbilt AF Registry. AF burden was assessed using the Toronto Atrial Fibrillation Severity Scale (AFSS), a validated survey tool measuring the frequency, duration and severity of AF episodes. BMI was categorized according to WHO guidelines, with BMIs of 18.5 kg/m2-25 kg/m2 considered normal, 25 kg/m2-30 kg/m2 overweight, 30 kg/m2-35 kg/m2 obese and >35 kg/m2 morbidly obese. Patients were grouped according to their current AF treatment regimen; no treatment (n=195), rate control with AV-nodal blocking agents (n=388), rhythm control with AADs (n=678) and prior AF ablation (n=220).
Results: Morbidly obese patients had higher AFSS scores than normal and overweight patients in the rate control (43.57 vs 38.21: P=0.0057), AAD (46.61 vs. 41.08: P=0.00016) and ablation (44.01 vs. 39.02: P=0.047) groups. In univariate linear models, BMI was associated with an increase in the AFSS score in the rate control (0.27, 95% CI 0.05-0.5, P=0.0181), AAD (0.38, 95% CI 0.21-0.56, P=2.49 x 10-5) and ablation (0.38, 95% CI 0.03-0.73, P=0.033) groups. The association remained significant in the AAD group after adjusting for age, gender, race, and comorbidities (0.29, 95% CI 0.11-0.49, P=0.0024).
Conclusion: In conclusion, our results showed that obesity and increasing BMI were associated with a significant increase in patient-reported measures of AF symptom severity and frequency of AF episodes. The association was most significant in patients on rhythm control therapy with AADs. Further research is needed to determine whether this finding is due to an overlap between subjective obesity-related and AF-related symptoms, or whether obesity may modulate response to rhythm control therapies.
Author Disclosures: D. Dickerman: None. B. Chalazan: None. B. Shoemaker: None. D. Darbar: None.
- © 2015 by American Heart Association, Inc.