HealthDay News — Losing weight significantly reduced atrial fibrillation symptom burden and severity among overweight and obese patients with the disorder, according to researchers.
Patients who participated in an intensive weight-loss intervention experienced an 11.8 point reduction in atrial fibrillation symptom burden scores compared to a 2.6 point reduction among controls (P<0.001), Hany S. Abed, MBBS, from the University of Adelaide in Australia and colleagues reported in the Journal of the American Medical Association.
The research was published to coincide with the American Heart Association’s 2013 Scientific Sessions in Dallas.
Over a 15-month period, the intervention group achieved greater reductions in weight compared with the routine care group — 14.3 kg vs. 3.6 kg (P<0.001), the researchers found.
The single-center, partially blinded, randomized trial involved 150 overweight and obese ambulatory patients with a BMI of 32.8 kg/m.2 All patients had symptomatic atrial fibrillation and half the patients were on at least one anti-arrhythmic medication. Patients were randomized in a 1:1 ratio to weight management (intervention) or general lifestyle advice (control) and were followed for a median of 15 months.
The weight-loss intervention included a very low calorie diet, meal replacements, a written exercise plan, behavioral modification and in-person clinic visits every three months. Routine care consisted of written and verbal advice on nutrition and exercise. Controls were prescribed fish oil (3 g/day), unless they were taking dual antiplatelet agents or oral anticoagulants.
In addition to more weight loss, the intervention group also experienced significantly greater reductions in atrial fibrillation symptom burden scores, symptom severity scores, number of episodes, and cumulative duration, compared with the control group, as follows:
Symptom severity scores in the intervention group declined 8.4 points compared with 1.7 points among controls (P<0.001)
The average number of atrial fibrillation episodes declined an average of 2.5 events in the intervention group compared with no change in controls (P=0.01)
Cumulative atrial fibrillation duration decreased 692 minutes in the intervention group compared with 419 minutes among controls (P=0.002).
In both the intervention and control groups, there was a reduction in interventricular septal thickness (1.1 mm vs. 0.6 mm, P=0.02, respectively) and left atrial area (3.5 cm2 vs. 1.9 cm2, P=0.02, respectively), with significantly larger reductions in the intervention group.
“In this study, weight reduction with intensive risk factor management resulted in a reduction in atrial fibrillation symptom burden and severity and in beneficial cardiac remodeling,” the researchers wrote. “These findings support therapy directed at weight and risk factors in the management of atrial fibrillation.”