Weight Loss Doesnt Lower Diabetes-Related Heart Disease

BETHESDA, Md.New findings from a National Institutes of Health (NIH) study revealed an intensive diet and exercise program resulting in weight loss does not reduce cardiovascular events, such as heart attack and stroke, in people with long-standing type 2 diabetes. As a result of the findings, the studys data and safety monitoring board recommended stopping the intensive lifestyle intervention in September 2012, but encouraged the study to continue following all Look AHEAD participants to identify longer-term effects of the intervention.

The Look AHEAD (Action for Health in Diabetes) study tested whether a lifestyle intervention resulting in weight loss would reduce rates of heart disease, stroke, and cardiovascular-related deaths in overweight and obese people with type 2 diabetes, a group at increased risk for these events.

Researchers at 16 U.S. centers worked with 5,145 people, with half randomly assigned to receive an intensive lifestyle intervention and the other half to a general program of diabetes support and education. Both groups received routine medical care from their own health care providers. Participants were 45 to 76 years old when they enrolled in the study60% of enrollees were women, and more than 37% were from racial and ethnic minority groups. Researchers are now analyzing data to measure effects of the lifestyle intervention on subgroups, including racial and ethnic groups and people with a history of cardiovascular disease.

Although the intervention did not reduce cardiovascular events, Look AHEAD has shown other important health benefits of the lifestyle intervention, including decreasing sleep apnea, reducing the need for diabetes medications, helping to maintain physical mobility, and improving quality of life.

"Look AHEAD found that people who are obese and have type 2 diabetes can lose weight and maintain their weight loss with a lifestyle intervention," said Dr. Rena Wing, chair of the Look AHEAD study and professor of psychiatry and human behavior at Brown University. "Although the study found weight loss had many positive health benefits for people with type 2 diabetes, the weight loss did not reduce the number of cardiovascular events."

Data are currently being analyzed to fully understand the cardiovascular disease results. Investigators are preparing a report of the findings for a peer-reviewed publication.

Few, if any, studies of this size and duration have had comparable success in achieving and maintaining weight loss. Participants in the intervention group lost an average of more than 8% their initial body weight after one year of intervention. They maintained an average weight loss of nearly 5% at four years, an amount of weight loss that experts recommend to improve health. Participants in the diabetes support and education group lost about 1% of their initial weight after one and four years.

The intervention group did not have fewer cardiovascular events than the group receiving general diabetes support and education, but one positive factor we saw was that both groups had a low number of cardiovascular events compared to previous studies of people with diabetes," said Dr. Mary Evans, director of Special Projects in Nutrition, Obesity, and Digestive Diseases within the NIHs National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), the study's primary sponsor.