Lifestyle Intervention Did Not Reduce Cardiovascular Events in Obese Adults With Type 2 Diabetes
June 24, 2013
For obese people with type 2 diabetes, a long-term intensive lifestyle intervention program, focused on weight loss, can improve physical quality of life, reduce microvascular complications, lower the risk of depression and lower medical costs by reducing the need for hospitalizations, outpatient care and medications, according to research presented today at the American Diabetes Association’s 73rd Scientific Sessions®.
However, the intensive lifestyle intervention did not reduce the risk for heart attacks or strokes more than a comparison group given diabetes support and education, results from the Look AHEAD (Action for Health in Diabetes) clinical trial revealed. Look AHEAD is a two-armed randomized trial conducted in 16 centers across the United States with more than 5,000 overweight or obese adults aged 45-76 years diagnosed with type 2 diabetes. Funded by the National Institutes of Health National Institute of Diabetes and Digestive Kidney Diseases (NIDDK), the study assigned participants to one of two interventions: lifestyle (involving physical activity and weight loss), or diabetes support and education (involving three counseling sessions per year on nutrition, physical activity and social support).
"Participants were followed for up to 11.5 years, with a median follow-up of 9.6 years at the time the intervention ended. The primary goal was to determine whether the intensive intervention would reduce the risk of cardiovascular mortality and morbidity," said Rena Wing, PhD, chair of the Look AHEAD trial and professor of Psychiatry and Human Behavior at Alpert Medical School of Brown University in Providence, R.I.
Though participants in the intensive lifestyle intervention group initially lost 8.6 percent of body weight and maintained a loss of 6 percent of body weight at the end of intervention, which was better than researchers expected, the intensive lifestyle group did not reduce their risk of cardiovascular morbidity or mortality, or the level of LDL-cholesterol (the so-called “bad” cholesterol) compared to the group that received diabetes support and education. The support and education group lost 0.7 percent initially and 3.5 percent at the end of intervention.
Wing said there were numerous possible explanations for the unexpected results, including the greater use of medications to lower LDL cholesterol in the comparison condition, which may have minimized any difference between the groups. The study cannot rule out the possibility that greater weight losses might impact cardiovascular risk.
However, the intensive lifestyle intervention group did experience other benefits when compared to those in the comparison group, including reducing the risk of kidney disease, self-reported retinopathy and depressive symptoms. Other benefits included an improved physical quality of life, and reduced annual hospital rates and costs. Lifestyle intervention also produced greater reductions in A1C, and greater initial improvements in fitness and all CVD risk factors except LDL cholesterol.
"This study shows that overweight and obese adults with type 2 diabetes can lose weight and keep it off with many important health benefits," said Griffin P. Rodgers, MD, director of the National Institute of Diabetes and Digestive and Kidney Diseases, part of the National Institutes of Health, which funded the study. "It reinforces the recommendation that overweight and obese people with type 2 diabetes should increase their physical activity levels and lose weight to improve their health."
The American Diabetes Association is leading the fight to Stop Diabetes and its deadly consequences and fighting for those affected by diabetes. The Association funds research to prevent, cure and manage diabetes; delivers services to hundreds of communities; provides objective and credible information; and gives voice to those denied their rights because of diabetes. For the past 75 years, our mission has been to prevent and cure diabetes and to improve the lives of all people affected by diabetes.