Obese individuals may have elevated AF recurrence risk
MedWire News: Obese individuals are at increased risk for left atrial enlargement, which in turn may elevate their risk for atrial fibrillation (AF) recurrence and burden, study results suggest.
Previous studies have reported an association between obesity, left atrial size, and AF, say the authors.
"In our study, left atrial size was independently correlated with body mass index (BMI).
"Therefore, obesity may increase the rate of new-onset AF, the recurrence rate, the transition from paroxysmal to permanent AF, and total AF burden, not directly but through increased left atrial size," they explain.
The findings arise from a subanalysis of the AFFIRM (Atrial Fibrillation Follow-up Investigation of Rhythm Management) study, in which Maya Guglin (University of South Florida, Tampa, USA) and team assessed the rate of cardioversion, a surrogate marker of AF recurrence, among 2518 AF patients.
The number of follow-up visits made by patients when in AF was also measured as a surrogate marker of AF burden.
Over a mean follow-up period of 3.5 years, 22,753 follow-up visits and 1094 cardioversions occurred among the group.
When patients were grouped according to BMI <18.5 kg/m2 (underweight), 18.5-24.9 kg/m2 (normal weight), 25.0-29.9 kg/m2 (overweight), and >30 kg/m2 (obese), the team noted that obese patients had a 26.8% higher risk for cardioversion than normal weight patients.
In the American Journal of Cardiology, the researchers report an overall increase in risk for cardioversion of 1.7%, 8.8%, and 18.3% per BMI increase of 1, 5, and 10 kg/m2, respectively (p=0.006 for all).
They also observed a positive association between left atrial size and AF recurrence rate (p<0.001), and noted that BMI positively correlated with left atrial size, with a correlation coefficient of 0.22 (p<0.0001).
Guglin and team conclude: "Lifestyle modifications directed toward a healthier weight may reduce AF and all the risks and complications associated with it."
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By Lauretta Ihonor