Intensive lifestyle intervention yields greater weight loss than metformin in Latinas with prediabetes
Hispanic women with prediabetes assigned to a lifestyle intervention program saw a greater mean reduction in body weight at 12 months vs. those assigned to metformin therapy or usual care, according to findings from a randomized controlled trial.
“In a real-world setting, our study is the first to demonstrate that intensive lifestyle intervention is more effective than metformin at inducing clinically meaningful weight loss among Hispanic women (Latinas) with prediabetes,” Matthew J. O’Brien, MD, MSc, assistant professor of medicine and preventive medicine at the Northwestern University the Feinberg School of Medicine, told Endocrine Today. “Metformin produced modest weight loss that was not significantly different from standard care.”
O’Brien and colleagues analyzed data from 92 Spanish-speaking Hispanic women with a mean HbA1c of 5.9% recruited from Philadelphia between 2013 and 2015 (mean age, 45 years; mean BMI, 33.3 kg/m²; mean waist circumference, 97.4 cm; 20% with history of gestational diabetes). Researchers randomly assigned participants to intensive lifestyle intervention delivered by community health workers (n = 33), metformin therapy (n = 29; 850 mg twice daily) or standard care (n = 30; including written educational materials on diabetes prevention) for 12 months. Intensive lifestyle intervention included behavioral strategies such as goal-setting, self-monitoring, stimulus control and problem-solving to achieve 5% to 7% weight loss by improving dietary patterns and promoting at least 150 minutes per week of physical activity. The 24-session intervention was delivered in Spanish to four groups of five to nine participants, with each session lasting approximately 90 minutes (first 14 sessions weekly; final 10 sessions took place biweekly and then monthly). Data were collected at baseline, 6 and 12 months. Primary outcome was body weight at 12 months; secondary outcomes included waist circumference, blood pressure, HbA1c, fasting plasma glucose, insulin and lipid profile.
Within the cohort, 85 women completed 12-month study assessments. Researchers found that participants assigned to intensive lifestyle intervention experienced greater mean weight loss (–4 kg; 5%) vs. those assigned to metformin therapy (mean weight loss, –0.9 kg; 1.1%) or standard care (mean gain, 0.8 kg; 0.9%; P < .001 for all). Across treatment arms, 50% of women in the intensive lifestyle intervention group achieved 5% body weight loss vs. 14.8% in the metformin group and 7.1% for those receiving standard care. Participants assigned to lifestyle intervention also experienced a greater mean reduction in waist circumference vs. standard care (P = .001), and a marginal improvement in HbA1c vs. metformin or standard care (P = .063).
One participant assigned to standard care developed type 2 diabetes during the study; 12 women reverted to normal glucose tolerance during the trial, including seven in the intensive lifestyle intervention group, three in the metformin group and two in the standard care group.
“Our study confirms that intensive lifestyle interventions should be offered to adults with prediabetes to promote weight loss,” O’Brien said. “While metformin was not as effective at achieving this outcome, it can also be considered as a treatment option for prediabetes. More research is needed to definitively test the comparative effectiveness of intensive lifestyle interventions and metformin in real-world settings. Such trials should examine long-term differences in the incidence of diabetes and cardiovascular disease.” – by Regina Schaffer
Disclosure: The trial was conducted in partnership with Puentas de Salud, a Latino-serving community health care center in Philadelphia. The researchers report no relevant financial disclosures.