Weight-loss program participants who had a brief, monthly personal contact intervention most often a 10-15 minute phone conversation regained less weight than participants who were in a Web-based intervention or self-directed program, according to a study in the March 12 issue of JAMA.
Nearly two-thirds of U.S. adults are overweight or obese. Together overweight and obesity are the second leading cause of preventable death, primarily through effects on cardiovascular disease (CVD) risk factors (hypertension, dyslipidemia [abnormal amounts of lipids and lipoproteins in the blood], and type 2 diabetes). Weight loss improves these risk factors, and evidence suggests that benefits persist as long as weight loss is maintained, the authors write.
Relatively short-term (4-6 months) behavioral interventions for adults can result in clinically significant weight loss, but regaining weight is common. Given the vast scope of the overweight and obesity epidemic, there is a critical need for practical, affordable, and scalable intervention strategies that effectively maintain weight loss, they write. Despite the potential for health benefits of weight loss maintenance, there is little evidence, particularly from clinical trials, on how to accomplish this objective.
Laura P. Svetkey, M.D., of Duke University Medical Center, Durham, N.C., and colleagues conducted the Weight Loss Maintenance (WLM) trial, a comparison of strategies for maintaining weight loss for 30 months following initial weight loss in a large, diverse, adult population at high risk for CVD. The two-phase trial included 1,032 overweight or obese adults (38 percent African American, 63 percent women) with hypertension, dyslipidemia, or both who had lost at least 8.8 lbs. during a 6-month weight loss program (phase 1) and were randomized to a weight-loss maintenance intervention (phase 2).
The interventions included monthly personal contact, unlimited access to an interactive technologybased intervention, or a self-directed control, in which participants received minimal intervention. Monthly personal contact consisted of a case management approach with monthly person-to-person guidance and support. Participants had telephone contact with an interventionist for 5 to 15 minutes each month, except for every 4th month when they had a 45- to 60-minute individual face-to-face contact. The interactive technologybased intervention included unlimited access to a Web site designed to support weight loss maintenance, with interactive features allowing participants to set personal goals and action plans for the next week and to graph personal data over time.
Average weight at entry in the study was 213 lbs. During the initial 6-month program, average weight loss was 18.7 lbs. All groups regained weight after randomization by an average of 12.1 lbs. in the self-directed, 11.5 lbs. in the interactive technologybased, and 8.8 lbs. in the personal-contact group. The average weight at 30 months remained lower in each group than average weight at entry into the study.
At 30 months after randomization, on average those in the personal-contact group regained 3.3 lbs. less weight than those in the self-directed group, whereas those in the interactive technologybased group regained only .7 lbs. less than those in the self-directed group. Those in the personal-contact group regained an average of 2.6 lbs. less than those in the interactive technologybased group. Overall, 41.8 percent of participants maintained at least 8.8 lbs. of weight loss compared with entry weight, with no significant differences between treatment groups; 70.9 percent remained at or below their entry weight.
Although weight regain with the personal-contact intervention was statistically less than weight regain in the self-directed control group, the [average] effect was a modest 1.5 kg [3.3 lbs.] at the end of the study. However, even modest weight loss can improve cardiovascular risk factors. Each kilogram [2.2 lbs.] of weight loss is associated with an average decrease in systolic blood pressure of 1.0 to 2.4 mm Hg and a reduction in incident diabetes of 16 percent, the author write. At the end of the study, more than 45 percent of those in the personal-contact intervention were still maintaining at least [8.8 lbs.] of weight loss, an amount with clear clinical benefits.
Future research should focus on longer intervention and follow-up, understanding predictors of successful maintenance and further refinement of both personal-contact and interactive technologybased interventions, the researchers conclude.