Lifestyle intervention is beneficial for most people with type 2 diabetes, but not all
For people who are overweight or obese and have type 2 diabetes, the first line of treatment is usually lifestyle intervention, including weight loss and increased physical activity. While this approach has cardiovascular benefit for many, it can be detrimental for people who have poor blood sugar control, according to a study conducted by researchers at Wake Forest School of Medicine.
In the study, published in the current issue of the journal Diabetes Care, the researchers re-evaluated the National Institutes of Health Action for Health in Diabetes (Look AHEAD) study that found intensive lifestyle intervention (ILI) neither helped nor hurt people with diabetes.
"Contrary to the initial findings of Look AHEAD, our work found that lifestyle interventions reduced potential cardiovascular harm and optimized benefits for 85% of those in the trial," said the study's lead investigator, Michael P. Bancks, Ph.D., assistant professor of public health sciences at Wake Forest School of Medicine, part of Wake Forest Baptist Health.
"However, for those who had poor blood sugar control, lifestyle intervention increased the risk of major cardiovascular events. Based on our findings, doctors may want to consider alternative options, such as glucose-lowering drugs, before trying lifestyle modification for those people."
Look AHEAD randomized 5145 participants with type 2 diabetes (T2D) who were overweight or obese to 10 years of ILI or a control group that received diabetes support and education. ILI focused on weight loss through decreased caloric intake and increased physical activity.
In the Wake Forest School of Medicine study, the researchers divided the study participants into four subgroups: diabetes onset at older age, poor glycemic control, severe obesity and younger age at onset. These subgroups were determined based on diabetes diagnosis, body mass index, waist circumference, measure of blood sugar value (glycemic control) and the age of diabetes onset.
Bancks and his team examined each group's response to the intensive lifestyle intervention and its association with major cardiovascular events. In the subgroup with poor glycemic control, the intervention was associated with 85% higher risk of having a cardiovascular event as compared to the control group. Among the three other diabetes subgroups analyzed, ILI was not associated with an increased risk of fatal and non-fatal cardiovascular events.
"Although the interest in diabetes subgroups is growing, our study is one of the first to apply it to lifestyle intervention," Bancks said. "So for clinicians, determining which subgroup their patient most closely resembles should help them determine the best treatment option and reduce any potential harm for that individual."
These results provide support for further investigation into whether these findings apply to other diabetes complications, including cognitive issues, and to assess what interventions would be beneficial for those individuals, Bancks said.