Adults with obesity and prediabetes experienced greater sustained improvements in both HbA1c and fasting glucose when assigned to a 24-session behavioral weight-loss program vs. similar adults assigned to shorter programs, according to findings published in BMJ Open Diabetes Research & Care.
Michael G. Perri
“For people with obesity and a blood glucose value in the prediabetes range, weight loss can help prevent or forestall the onset of type 2 diabetes,” Michael G. Perri, PhD, ABPP, dean and Robert G. Frank endowed professor at the College of Public Health and Health Professions, University of Florida, told Endocrine Today. “For such individuals, clinical guidelines commonly recommend a ‘moderate’ dose behavioral weight-loss treatment consisting of 16 weekly sessions. In our study, we found that a ‘high’ dose of treatment consisting of 24 weekly sessions may be needed to maximize improvements in glycemic control.”
Perri and colleagues analyzed data from 287 adults with obesity (mean age, 54 years; 77% women; 81% white) who participated in the Rural LITE trial, a study assessing the benefits of high-dose (24 weekly sessions over 6 months; n = 71), moderate-dose (16 weekly sessions over 4 months; n = 65) and low-dose (eight weekly sessions over 2 months; n = 74) behavioral weight-loss sessions vs. a nutrition education control group (eight weekly sessions over 2 months; n = 77) on changes in HbA1c, fasting glucose and body weight. All sessions were delivered in 90-minute group settings with content based on the CDC’s National Diabetes Prevention Program. For the intervention groups, researchers instructed participants to follow a low-calorie diet, increase physical activity using a home-based walking program and employ behavior change strategies (goal setting, daily steps and problem-solving techniques).
“In contrast to the behavioral treatment groups, participants in the control condition were not assigned calorie intake or physical activity goals, and they did not receive instruction on behavioral strategies for weight management,” the researchers wrote.
At baseline, mean BMI for the cohort was 36.3 kg/m², and mean HbA1c was 5.9%.
Researchers observed mean HbA1c decreases of –0.11% (95% credible interval [CI], 0.07-0.16) in the high-dose group, –0.08% (95% CI, 0.03-0.13) in the moderate-dose group, –0.03% (95% CI, –0.01 to 0.07) in the low-dose group and –0.02% (95% CI, –0.02 to 0.07) in the control group between baseline and 6 months. For fasting blood glucose, mean decreases were –0.26 mmol/L (95% CI, 0.14-0.39) in the high-dose group, –0.09 mmol/L (95% CI, 0-0.19) in the moderate-dose group, –0.01 mmol/L (95% CI, –0.07 to 0.09) in the low-dose group and –0.04 mmol/L (95% CI, –0.03 to 0.12) in the control group.
In an exploratory analysis assessing the effect of treatment assignment on achieving a clinically significant HbA1c reduction, researchers found that 37% of participants in the high-dose group, 30.3% in the moderate-dose group, 18.6% in the low-dose group and 15.5% in the control group achieved an HbA1c reduction of at least 0.3%.
For changes in body weight, researchers observed mean reductions of –10.91 kg (95% CI, 9.3-12.64) in the high-dose group, –10.08 kg (95% CI, 8.38-11.72) in the moderate-dose group, –6.35 kg (95% CI, 5.19-7.69) in the low-dose group and –3.82 kg (95% CI, 3.04-4.54) in the control group. The difference in 6-month weight change between the high-dose vs. moderate-dose groups did not rise to significance, according to researchers.
“When recommending weight loss for adults with obesity and prediabetes, clinicians should consider prescribing a high dose of behavioral weight-loss treatment,” Perri said. “Research is needed to determine whether the longer period of negative energy balance (ie, dieting) or the greater degree of weight loss associated with high-dose treatment is responsible for the observed improvements in glycemic control.” – by Regina Schaffer
For more information:
Michael G. Perri, PhD, ABPP, can be reached at the University of Florida, College of Public Health and Health Professions, P.O. Box 100185, 1225 Center Drive, HPNP Suite 4101, Gainsville, FL 32610; email: email@example.com.
Disclosures: The NIH funded this study. The authors report no relevant financial disclosures.