Intensive lifestyle intervention reduces long-term variability in blood sugar, lipids

For people with overweight or obesity and type 2 diabetes (T2D), intensive lifestyle intervention (ILI) appears to minimize the spikes and drops in cardiovascular risk factors such as blood glucose and lipids.

In the post hoc secondary analysis of the Look AHEAD* study, ILI was associated with significantly reduced variability in fasting blood glucose (FBG; β, −1.49, 95 percent confidence interval [CI], −2.39 to −0.59; p=0.001), total cholesterol (TC; β, −1.12, 95 percent CI, −1.75 to −0.48; p=0.001), and low‐density lipoprotein cholesterol (LDL‐C; β, −1.04, 95 percent CI, −1.59 to −0.49; p<0.001) over a 4-year follow-up as compared with diabetes support and education. [J Am Heart Assoc 2024;doi:10.1161/JAHA.123.030132]

However, ILI also led to increased variability in systolic blood pressure (SBP; β, 0.27, 95 percent CI, 0.00–0.54; p=0.047).

The 4-year ILI was aimed at achieving and maintaining at least a 7-percent decrease in weight from baseline and 175 minutes per week in physical activity through individual supervision and group sessions. The intervention began with a year of intensive support, followed by 3 years of less frequent but ongoing engagement. Participant progress was monitored, with several diet (prepared meals and liquid formula) and exercise strategies and optional weight loss medications being used to aid in weight loss. On the other hand, diabetes support and education involved diabetes management and social support sessions, which were held three times a year. 

“The results of this study highlight the importance of ILI to reduce variability [in] cardiovascular risk factors in adults with overweight or obesity and T2D,” the investigators said. “ILI should be recommended to individuals with diabetes as part of management of long‐term glycaemic and blood lipid control.”

The role of fluctuations

“To our knowledge, our study is the first comprehensive report on the association of ILI with the variability in cardiovascular risk factors,” the investigators noted, adding that clinical practice has centred on individual metabolic parameters rather than on long-term variability of cardiovascular risk factors.

Existing research provides strong evidence for the cardiovascular benefits of lowering risk factors, but no studies to date have conclusively shown that solely reducing the fluctuations in such risk factors leads to similar improvements, they continued.

“[F]rom a therapeutic viewpoint, it seems reasonable to make an attempt to reduce the variability of cardiovascular risk factors,” given that a variability in blood glucose, lipids, and blood pressure over time has been linked to increased risks of death and cardiovascular events, according to the investigators. [BMJ 2016; 354:i4098; Lancet Diabetes Endocrinol 2019;7:221-230; Eur Heart J 2018;39:2551-2558; Circulation 2018;138:2627-2637]

“Our results support ILI as a viable and sustainable approach to aid clinical decision making and provided the new evidence for the recommendations contained in the current guidelines,” they added.

The analysis included 4,249 adults (mean age 58.9 years, 41.5 percent men, 66.8 percent White) with overweight or obesity and T2D who participated in Look AHEAD. Of these, 2,162 underwent ILI and 2,087 received diabetes support and education. Cardiovascular risk factors were measured annually over 4 years. Long‐term variability was defined as the standard deviation of the parameters measured.

The study had several limitations, including the lack of data on the participants’ adherence to their medications, the inability to control for dietary pattern, and the limited generalizability due to the inclusion only of people who could successfully complete a maximal fitness test at baseline.

*Action for Health in Diabetes