Diabetes Dateline
Spring/Summer 2008

First Year of Look AHEAD Trial Yields Encouraging Results

Overweight or obese people with diabetes who have received a year of intensive lifestyle intervention—including regular individual and group counseling, structured meal plans, and customized exercise programs—lost an average 8.6 percent of their initial body weight, according to first-year results of the Look AHEAD (Action for Health in Diabetes) clinical trial funded by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). By comparison, a similar group that received standard diabetes education and support lost only 0.7 percent of their weight.

The Look AHEAD trial is examining the efficacy of an intensive lifestyle intervention strategy in reducing major cardiovascular disease (CVD) events, including heart attack and stroke, in overweight or obese people with diabetes. The strategy emphasizes calorie reduction and increased physical activity to achieve long-term weight loss.

“A 7 to 10 percent weight loss has a big clinical impact,” said Rena Wing, Ph.D., M.A., a professor of psychiatry and human behavior at Brown University and chair of the Look AHEAD trial. In addition, “every single parameter that we measured improved in both groups,” she said.

But participants in the lifestyle intervention group saw greater reductions in CVD risk factors, including improvements in hypertension, cholesterol and triglyceride levels, and urine-to-creatinine ratios. From a beginning average of 7.3 percent, the mean A1C level dropped to 6.6 percent in the lifestyle intervention group, versus 7.2 percent in the group that received the usual care. The A1C test estimates a person's average level of blood glucose, also called blood sugar, from the previous 3 months. The target A1C value is less than 7 percent.

Lifestyle intervention group participants also reduced their use of diabetes, blood pressure, and lipid-lowering medicines while improving control of these factors.

Further Study Needed

“The goal is to assess the impact of weight loss and sustaining that weight loss over the long term on CVD risk and events in overweight and obese people with type 2 diabetes,” said Mary Evans, Ph.D., program director for Look AHEAD and NIDDK director of Special Projects in Nutrition, Obesity, and Digestive Diseases.

The trial, which began in 2001, is following about 5,000 overweight or obese men and women with type 2 diabetes for up to 11.5 years. At enrollment, trial participants were between the ages of 45 and 75.

After providing an initial session of diabetes education about the importance of diet and exercise, foot care, and managing hyperglycemia, researchers split participants into two groups. Those in the lifestyle intervention group receive intense counseling while striving to meet a 10 percent weight loss goal through a strategy that emphasizes calorie reduction and increased physical activity but also allows the use of weight-loss drugs for some who were not meeting weight-loss goals at 6 months. The remaining half receive standard diabetes support and education at the initial meeting and at three follow-up visits throughout the year.

The intensive lifestyle intervention will last 4 years, after which participants will be offered maintenance counseling. Look AHEAD investigators plan to publish 4-year results in 2009.

Several ancillary studies on topics such as sleep apnea, fatty liver disease, and eating disorders also are under way.

Although first-year results are encouraging, said Wing, Look AHEAD researchers won’t know if reductions in CVD risk translate to actual reduced major CVD events until the trial’s conclusion in 2012.

For more information about NIDDK-funded research on diabetes, visit www2.niddk.nih.gov/Research/ScientificAreas/Diabetes. For information about diabetes, diet, and physical activity, go to www.diabetes.niddk.nih.gov.

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NIH Publication No. 08–4562
August 2008