An intensive lifestyle intervention program designed with weight loss in mind improves diabetes control and cardiovascular disease risk factors in overweight and obese individuals with type 2 diabetes. These are the findings of the four-year Look AHEAD study, funded by the National Institutes of Health and the Centers for Disease Control and Prevention. Look AHEAD (Action for Health in Diabetes) is a multi-center, randomized clinical trial evaluating the effect of reduced caloric intake and increased physical activity on the incidence of major cardiovascular events such as heart attack, stroke, and cardiovascular-related death.
According to the National Institutes of Health, at study entry there were 5,145 participants at 16 centers across the United States, randomly assigned to one of two interventions. Those in the intensive lifestyle intervention group met regularly with a lifestyle counselor, as well as attending group and individual sessions. They were given specific caloric consumption and exercise goals, were encouraged to maintain a diet and exercise diary, and were taught behavioral skills such as problem solving and goal setting. After the first year, participants were seen individually at least once monthly, had at least one additional phone or email contact each month, and were invited to attend additional group classes. The second group were invited to group sessions each year focused on diet, physical activity, or social support. They were not weighed at these sessions or counseled on behavioral strategies.
At the time of enrollment, participants were between 45 and 76 years of age and most were obese, with a mean body mass index (BMI) of 36. Thirty-seven percent of participants were from ethnic minority groups, and approximately 60 percent were women. Over 94 percent of participants remain involved after four years and will continue to be followed for up to 13.5 years. The study will continue to examine whether improvements in risk factors, including blood pressure, lipids and glucose control, can be sustained – independently and as a consequence of continued weight loss – and whether the intensive lifestyle intervention is effective in reducing the incidence of illness and death due to cardiovascular disease. These results will not be available for several years.
Four years into the study, participants in both groups showed positive changes in their health. But the results don’t stop there. In the four years, the participants in the lifestyle intervention group lost an average of 6.2 percent of their body weight, compared with 0.9 percent for the diabetes support group. The lifestyle intervention group also had greater improvements in fitness, blood glucose control, blood pressure, and levels of “good” HDL cholesterol.
“Although the differences between the two groups were greatest initially and decreased over time for several measures, the differences between the two groups averaged across the four years were substantial. [The results] indicate that the intensive lifestyle intervention group spent a considerable time at lower cardiovascular disease risk,” the researchers wrote.
According to Griffin P. Rodgers, M.D., director of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), the primary sponsor of the study, “This important study shows that lifestyle changes have long-term favorable effects on diabetes control and cardiovascular disease risk factors in overweight or obese individuals with type 2 diabetes.”
The results are published in the Sept. 27, 2010, issue of the Archives of Internal Medicine.
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