For obese people with type 2 diabetes, a long-term intensive lifestyle intervention program, focused on weight loss, can achieve various improvements but does not affect the risk of cardiac arrest or stroke, according to a study.
The intervention 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 June 24 at the American Diabetes Associations annual scientific sessions.
However, the intervention did not reduce the risk of cardiac arrest or stroke 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 ages 45 to 76 who were diagnosed with type 2 diabetes. Funded by the National Institute of Diabetes and Digestive Kidney Diseases, part of the National Institutes of Health, 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, said Rena Wing, PhD, chair of the Look AHEAD trial and a professor of psychiatry and human behavior at the Alpert Medical School of Brown University in Providence, R.I.
The primary goal was to determine whether the intensive intervention would reduce the risk of cardiovascular mortality and morbidity, Wing said in a news release.
Alhough participants in the intensive lifestyle intervention group surpassed the researchers expectations by initially losing 8.6% of body weight and maintaining a loss of 6% of body weight at the end of intervention, they did not reduce their risk of cardiovascular morbidity or mortality, or their level of LDL-cholesterol, compared with the group that received diabetes support and education. The support and education group lost 0.7% of body weight initially and 3.5% 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 support and education group, which may have minimized any difference between the groups. The researchers could not rule out the possibility that more substantial weight loss might affect cardiovascular risk.
However, the intensive lifestyle intervention group experienced other benefits when compared with 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. The lifestyle intervention also produced greater reductions in A1, 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,” Griffin P. Rodgers, MD, director of the National Institute of Diabetes and Digestive and Kidney Diseases, said in the news release. “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.”