A new review of studies spread over five continents finds that overweight or obese children and teens can lose weight with lifestyle changes, sometimes coupled with medication.
Lead reviewer Hiltje Oude Luttikhuis, M.D., with the Beatrix Children's Hospital in Groningen, the Netherlands, and her colleagues analyzed 64 randomized controlled trials of lifestyle therapy and drug interventions.
Behavioral lifestyle therapy aims to change thinking patterns and actions. For example, children and adolescents were encouraged to have breakfast and to eat regular meals, while controlling portions. They were also encouraged to reduce sedentary behaviors, like watching TV, and to increase physical activity. Techniques used to change these thinking patterns included self-awareness, self-monitoring and goal setting for eating and physical activity. Participants also learned cognitive behavior strategies that included ways to deal with stress.
Studies took place in North America, Europe, Australia, Asia and South America (Brazil).
The new review appears in the latest issue of The Cochrane Library
, a publication of The Cochrane Collaboration, an international organization that evaluates medical research.
Systematic reviews like this one draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic.
Although this research cannot pinpoint the ultimate treatment for childhood obesity, the reviewers found several studies that highlighted the importance of combined dietary, physical activity and behavioral components. Parental involvement was an important feature of behavioral programs, particularly in pre-adolescent children.
Citing increasing rates of overweight and obesity worldwide, Oude Luttikhuis said, "More than 30 percent of children and adolescents in the Americas, for example, are overweight or obese. Even in the Netherlands, this prevalence in childhood obesity is going up. We conducted this study because we wanted to understand how best to intervene."
Review studies comprised 5,230 participants. Fifty-four lifestyle studies focused on some aspect of diet, physical activity or other behavior changes for 3,806 participants. Ten studies focused on drug intervention in addition to lifestyle changes for 1,424 participants. Only 18 of 54 lifestyle studies reported measures of harm; of these, no adverse effects occurred.
Drug interventions included orlistat and sibutramine, which researchers tested with moderately to severely obese adolescents. Orlistat works by inhibiting the absorption of dietary fats. In contrast, sibutramine is an appetite suppressant that works by making people feel full, so they want to eat less.
A range of side effects occurred, depending on the drugs. From the meta-analysis, Oude Luttikhuis could not discern whether one medication was more efficient than another, but both drugs significantly reduced obesity. However, she said that it is important to weigh the beneficial effects against the side effects. What is clear, she said, is that when drug therapy is used, it should be given in combination with lifestyle interventions.
She said she especially was surprised to find a lack of studies in preschool age children: "Ideally, the treatment, and prevention, of obesity should begin before children go to school, where they might be subjected to discrimination, because of their weight."
She added, "Doctors should not despair and feel drugs are vital, if a teen has become obese. Already, we have seen large effects in weight loss from lifestyle changes alone. It is disappointing that we have to consider drug or surgical interventions with problems that might have been altered by lifestyle changes earlier on."
The clinical studies were quite varied in how they were conducted, making it difficult to synthesize the results. Interventions in children under 12, for instance, were often different from studies for adolescents. Further, most clinical studies used small samples of children and adolescents.
"This evidence review does an excellent job of reviewing current treatment options for obesity in children and adolescents," said Alice Ammerman, director of the Center for Health Promotion and Disease Prevention at the University of North Carolina at Chapel Hill. She added, however, that while it is beyond the scope of this review, it is critical to consider the policy, environmental and systems changes needed to create a situation where children and their families can make healthful choices.
"This includes improved opportunities for walking and bicycling within communities, better access to high quality fruits and vegetables for families of all income levels, and improved nutrition and physical activity environments within schools," Ammerman said.
"Until we address these broader issues, individual level obesity treatment programs for children are unlikely to have a long-term impact."