They also took fewer medicines and were hospitalized less often, in the study released Monday at an American Diabetes Association meeting and in the New England Journal of Medicine. Medical costs for the intervention group were lower by $600 per person per year, said Rena Wing, a Brown University professor of psychiatry who led the study.
The trial was stopped last year after analysts determined that patients in the behavior-modification arm were doing no better than the control group when it came to death from cardiovascular causes, nonfatal strokes, and heart attacks, and hospitalization for angina.
Thomas Wadden, director of the University of Pennsylvania's Center for Weight and Eating Disorders, said the trial "missed the home run" but supplied a lot of singles, doubles, and triples. Penn was one of 16 centers around the nation that conducted the randomized trial. It followed more than 5,000 people for a median of 9.6 years.
"On the whole, I think we will find that the lifestyle intervention was associated with numerous critical improvements in health and well being," Wadden said.
He worries that overweight diabetics might see the study as a reason to "throw out the baby with the bath water" and give up on lifestyle changes.
"I just don't want people to hear about these people and think, 'OK, I can sit on the couch and eat a bag of Doritos and watch TV all night,' " he said.
A previous study showed that a similar approach to weight loss and exercise could prevent the onset of diabetes. People who are obese and have type 2 diabetes have more heart problems than healthy people with normal weights.
Participants in the lifestyle-change arm had weekly meetings with a counselor at the beginning and monthly meetings later on. Patients were to eat 1,200 to 1,500 calories a day and exercise 175 minutes a week.
They lost 8.6 percent of body weight during the first year and were still 6 percent lighter at study's end. This doesn't sound like much, but for a lifestyle program, it's "incredibly impressive," said Gary Foster, a Temple University obesity expert, who was involved in the early years of the study.
Those in the control group received their usual medical care with extra education and monitoring. They lost a negligible amount at first, but were 3.5 percent lighter at the end.
Researchers don't know why they lost weight. That might be an effect of the kinds of people who join studies, the extra information and monitoring, aging or diabetes.
Wadden said researchers expected 3 percent of the control group to have heart "events" each year when the study started in 1999. Instead, only 2 percent did. "A lot of that reflects the improvement in medical care," he said.
The scientists don't know why the two groups were not more different. It could be that the weight loss was too small or the time too short. Patients in the control group took more statin medications to reduce cholesterol. Ray Belikoff, 68, of Philadelphia, who participated in the study, started out at 290 pounds. He was taking insulin, had peripheral neuropathy, and learned that he had had a "silent" heart attack.
"I felt at that time that I was literally circling the drain," he said.
A star student, he now weighs 184 pounds and is off insulin. He still takes medicine for the neuropathy, but it hasn't gotten worse. There's been no more heart trouble.
Regardless of the study's findings, he thinks it makes "common sense" that excess weight strains the heart. "I'm sure that it benefited me," he said of the study.
The patients are still being followed to see if more differences emerge over time.
Contact Stacey Burling at 215-854-4944 or firstname.lastname@example.org.