Studying efforts to combat obesity in children, a research team led by investigators at Washington University School of Medicine in St. Louis has found that children who lose weight are able to keep it off more effectively if they participate in a maintenance-targeted treatment program, although the effectiveness of the maintenance program lessens over time. The researchers report their findings in the Oct. 10 issue of the Journal of the American Medical Association.
“Maintenance of weight loss is essential to avoid the physical and psychosocial consequences of chronic obesity,” says principal investigator Denise E. Wilfley, Ph.D., director of the Weight Management and Eating Disorders Program at the School of Medicine. “Active maintenance treatment resulted in significantly better maintenance of weight loss.”
The number of overweight children in the United States has tripled in recent decades, and related health-care costs have nearly quadrupled. Nationwide, 19 percent of children ages 6 to 11 and 17 percent of those 12 to 19 are overweight, according to the Centers for Disease Control and Prevention. Those who are overweight during childhood also have an increased risk of obesity in adulthood and are at greater risk for health complications such as diabetes, high blood pressure, heart disease and stroke. Those who are overweight and obese also are at greater risk for psychological and social problems
“Just as with adults, interventions to help kids lose weight are effective in the short term, but maintaining weight loss remains a challenge, and most interventions are marked by considerable relapse rates,” says Wilfley, a professor of psychiatry, of medicine and of pediatrics at the School of Medicine and professor of psychology in Arts & Sciences at Washington University in St. Louis “This was the first study to examine whether extending treatment contact would help children maintain weight loss, and we found an active, maintenance treatment program did help.”
The researchers studied 150 children in San Diego, Calif. who were between the ages of 7 and 12 and had body mass indices (BMI) that averaged more than 60 percent above the median BMI for their age and sex. For example, an average 8-year-old boy is 4 feet, 2 inches tall, with a BMI of 15.78 and a weight of 57 pounds, but the average 8-year-old boy in this study had a BMI of 25.25 and weighed more than 91 pounds. All of the children in the study also had at least one parent who was overweight.
These children participated in a family-based weight-loss treatment program for five months. Then they were randomly assigned to one of three groups: a behavioral skills maintenance (BSM) treatment group, a social facilitation maintenance (SFM) group or a control group that received no active treatment after the initial, weight-loss program.
The BSM approach is based on the premise that specific behavioral skills are needed for weight loss maintenance. BSM focuses on enhancing the motivation of parents and children and on behavioral skills needed for long-term weight control — such as learning to monitor body weight and to return to weight-loss strategies when they begin to regain weight.
The SFM approach presumes that people need a social environment that supports continued weight control. The SFM treatment guided parents to encourage their kids to be friends with physically active peers and to ensure that play dates with existing friends involved physical activity and healthful eating.
Both maintenance programs lasted four months. Researchers then took the height and weight of the children one year and two years after the initial weight-loss program. Most kids had significant decreases in their amounts of weight during the weight-loss intervention, but without a formal maintenance program, they tended to return to their previous overweight levels. In fact, although the weight percentage of children in the control group fell by 11 percent during the weight loss program, two years later those same children had returned to their previous level of overweight, plus 2.6 percent.
“Children from both maintenance treatment groups had significantly more success maintaining weight loss than children in the control group,” Wilfley says.
Those children who participated in either the BSM or SFM program maintained their relative weight significantly better than those who did not receive maintenance treatment. The relative effectiveness of the active maintenance treatment declined during follow-up, and although there were no significant differences, child weight outcomes were not identical between the two interventions. The investigators found that the SFM intervention was more beneficial in children with better social skills. Those children maintained a weight status similar to that observed immediately following the weight-loss program.
“Our results indicate that when compared to the BSM intervention and the control group, children in the SFM group were significantly more successful in enlisting peers to assist them in increasing physical activity and sticking with healthful eating behaviors,” Wilfley explains. “The children in the SFM group also were better able to cope with teasing, and these types of psychosocial changes are associated with positive weight control behaviors.”
This study did not specifically examine the health benefits of weight loss in these children, instead focusing more on the basics of weight loss and maintenance. But Wilfley reasons that losing weight and keeping it off will offer future dividends because more than 80 percent of people who develop type 2 diabetes are overweight. Overweight people also are more likely to have high blood pressure and other risk factors for heart disease and stroke.
“The alarming number of overweight children in our society means we need to develop more effective long-term intervention strategies, and we plan to devote more study to the hypothesis that positive peer support can assist children in long-term weight control,” Wilfley says.
Wilfley DE, Stein RI, Saelens BE, Mockus DS, Matt GE, Hayden-Wade HA, Welch RR, Schechtman KB, Thompson PA, Epstein LH. Efficacy of maintenance treatment approaches for childhood overweight: a randomized controlled trial, Journal of the American Medical Association; vol. 298 (14), pp. 1661-1673, Oct 10, 2007.
This research was funded by grants from the National Institute of Child Health and Human Development (NICHD), the National Institute of Mental Health (NIMH) and the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) of the National Institutes of Health.
Washington University School of Medicine’s 2,100 employed and volunteer faculty physicians also are the medical staff of Barnes-Jewish and St. Louis Children’s hospitals. The School of Medicine is one of the leading medical research, teaching and patient care institutions in the nation, currently ranked fourth in the nation by U.S. News & World Report. Through its affiliations with Barnes-Jewish and St. Louis Children’s hospitals, the School of Medicine is linked to BJC HealthCare.