Obese patients with atrial fibrillation who lost at least 10 percent of their body weight were six times more likely to achieve long-term freedom from this common heart rhythm disorder compared to those who did not lose weight, according to a study presented at the American College of Cardiology's 64th Annual Scientific Session. The study is the first to track the long-term effects of weight loss and the degree of weight fluctuation on atrial fibrillation burden. Patients who lost more weight and maintained a more stable weight over four years showed marked reductions in atrial fibrillation burden and severity, the study's primary endpoints.

"Previous studies have shown that weight management can reduce atrial fibrillation symptoms in the short term and improve outcomes of ablation [a surgical treatment for atrial fibrillation]," said Rajeev Pathak, M.D., a cardiologist and electrophysiology fellow at the University of Adelaide, Adelaide, Australia and the study's lead author. "We sought to shed light on the long-term outcomes of sustained weight loss, the effects of the amount of weight lost and the impact of changes in weight over time."

An estimated 5.6 million U.S. adults have atrial fibrillation, which can cause episodes of weakness, shortness of breath and palpitations and increases the risk of more serious problems such as stroke. Obesity, seen in more than one-third of U.S. adults, is associated with an increased risk of atrial fibrillation.

"We found that sustained weight loss is achievable in obese patients and that it can significantly reduce the burden of atrial fibrillation," Pathak said. "Weight loss also led to favorable changes in cardiovascular risk factors such as high blood pressure, obstructive sleep apnea and diabetes, along with improvements in the structure and function of the heart."