Washington, April 8 (ANI): A new study by researchers at Duke University Medical Center has found that heart failure patients who regularly exercise fare better and feel better about their lives than do similar patients who do not work out on a regular basis.
"Past studies have sent mixed signals about the merit of exercise for patients with heart failure. The HF-ACTION study (A Controlled Trial Investigating Outcomes Exercise Training) shows that exercise is not only safe for patients, but also helps to improve the quality of their lives, overall," said Kathryn Flynn, Ph.D., a health services researcher at the Duke Clinical Research Institute (DCRI) and lead author of the study.
For the study, researchers enrolled 2331 patients with moderate to severe heart failure at 82 sites throughout the U.S., Canada and France from 2003 to 2008.
Researchers randomized participants to receive either standard care or standard care plus an exercise program. The exercise regimen consisted of three months of supervised aerobic training on a bicycle or treadmill, followed by instruction for continued home-based training.
Researchers set the exercise goal at five, 40-minute workouts, or 200 minutes of exercise per week. Participants reached about 60 percent of that goal at one year. Participants had significant heart failure upon entering the study, measured by diminished left ventricular ejection fraction (mean, 25 percent).
Ninety-five per cent of the patients were taking medications for heart failure, such as ACE-inhibitors or beta-blockers, and 40 percent were using mechanical devices to boost their hearts' ability to pump or to treat arrhythmias. The average age of the patients was 59; 28 percent were women.
Upon enrollment, patients filled out the Kansas City Cardiomyopathy Questionnaire (KCCQ), a 23-item measure shown to be responsive to underlying clinical changes in patients with heart failure.
The KCCQ generated an overall measure of quality of life and subscale measures reflecting the patients' physical limitations, symptoms, quality of life and social restrictions. Participants completed the questionnaire at three-month intervals for the first 12 months, and annually thereafter. The average time of follow-up was two and one-half years.
There were no significant differences between the two patient groups at baseline. The average overall KCCQ score among patients in both groups was 66.
At three months, patients in both groups showed improvement, with patients in the usual care group registering an average three-point gain on the KCCQ score and those in the exercise group showing an average five-point gain. Previous reports had defined a five-point gain as clinically significant.
Researchers also looked at how individual patients responded to exercise training and found that a higher percentage of those in the exercise group experienced clinical meaningful improvement.
At three months, 54 percent of those in the exercise group saw a five-point gain in overall KCCQ score, while only 28 percent of those in the usual care group met that goal. The study has been published in the April 8 issue of the Journal of the American Medical Association. (ANI)