By Andrew M. Seaman
NEW YORK (Reuters Health) - People with an irregular heart rhythm could see an improvement in symptoms if they lose weight in addition to managing their other heart risks, says a new study.
Researchers found that people who lost more than 30 pounds and kept their other health conditions in check saw greater improvements in atrial fibrillation symptoms than those who just managed their other health conditions without trying to lose weight.
"Risk factor management is a crucial component of managing atrial fibrillation," Dr. Prashanthan Sanders, the study's lead author from the Royal Adelaide Hospital in Australia, said.
"I think that's what the public needs to be aware of and it's not out there yet," he added.
Atrial fibrillation (AF) is a type of rhythm disorder affecting the heart's upper chambers. It can be caused by a number of issues - including heart attacks, infections and heart valve problems. Obesity is a risk factor for AF, as are high blood pressure, high cholesterol and diabetes.
Approximately five million people were diagnosed with AF in 2010. That number is expected to grow to about 12 million cases per year by 2030, according to one recent study (see Reuters Health story of Jul. 26, 2013 here: http://reut.rs/17gMbSk).
People with AF can experience racing and uncomfortable heartbeats, weakness, blood pressure problems, chest pains and other symptoms.
Sanders and his colleagues recruited 150 people with AF to participate in the study to see whether weight loss and well-managed risk factors helped ease symptoms. The results were published in the Journal of the American Medical Association.
The participants were patients between the ages of 21 and 75 years old at the Center for Heart Rhythm Disorders at the University of Adelaide. They were also all overweight.
At the beginning of the study in June 2010, the participants were randomly assigned to the weight loss group or to a comparison group.
Over a period of eight weeks, those in the weight loss group were put on low-calorie diets, which were eventually replaced with low-glycemic index meals. They were also told to exercise three times a week for 20 minutes. That eventually increased to 45 minutes three times per week.
Both groups got aggressive management of other risk factors, including medications to control blood pressure, cholesterol and blood sugar, as needed.
The participants assigned to the comparison group received nutrition and exercise advice as well.
The participants were followed for an average of 15 months. At the beginning of the study, participants in each group scored - on average - between 21 and 22 on a scale that measures AF symptoms.
The scale ranges from 3.25, for a single episode of symptoms lasting a few minutes, to 30, for continuous and intense symptoms lasting more than a couple of days.
At the end of the study, members of the weight loss group had dropped an average of 33 pounds each. And their AF symptom scale scores fell to about 9. That compared to an average score of about 19 among participants in the comparison group, whose average weight loss was about 12 pounds each.
Sanders told Reuters Health that the improvement observed in the weight loss group would also be noticeable to patients.
"Most of those patients we included were on our waiting list to undergo ablation procedures to eliminate their atrial fibrillation," he said, adding that most patients didn't end up needing the procedure after the study.
Dr. Bruce Lindsay told Reuters Health that he's not surprised by the study's findings. He's section head of cardiac electrophysiology and pacing at the Cleveland Clinic in Ohio.
"I think there has been some knowledge in the community that obesity is linked to atrial fibrillation," Lindsay, who was not involved in the new study, said.
"When I see patients who are overweight and I'm talking to them about the options for treatment, I try to make it clear that there are things we can do to help them but there are other things they can do," he said. Those things include weight loss.
Sanders said that people with AF should address their risk factors and talk with their doctors about weight loss options, including programs in their local community.
Lindsay said programs that focus on lifestyle changes, such as Weight Watchers, are best.
Sanders said there is no easy way to lose weight, but people with AF are encouraged to keep going as their symptoms improve.
"When they start seeing the effect of losing weight, they get motivated," he said.
SOURCE: http://bit.ly/1hRXAPx Journal of the American Medical Association, online November 17, 2013.