Rates of overweight and obesity in U.S. children and teens may be leveling off, but kids at the extreme - the severely obese - are still swelling in numbers and need attention, according to a new statement from the American Heart Association (AHA).
Between 4 percent and 6 percent of youth in the United States are severely obese, with serious accompanying health problems, the researchers say.
"Four to six percent of all children and adolescents in the U.S., we believe, is a striking number and something that needs to be addressed," statement co-author Aaron S. Kelly, of the University of Minnesota Medical School, said.
This group is "growing at a relatively rapid clip and that's concerning," he said. "We don't have many effective treatment options."
Last year, research from the U.S. Centers for Disease Control and Prevention showed a drop in obesity and extreme obesity among low-income preschoolers. Yet, the new AHA statement, using an updated definition of severe obesity, identifies a subset of youth for whom current prevention and treatment tactics don't appear to be working.
Kelly and his colleagues analyzed data from the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2006 and smaller studies to see how common severe obesity is among children and adolescents.
The researchers defined severe obesity by body mass index (BMI), a measure of weight relative to height. For children, BMI also takes into account the range of weights in a child's age group. So severe obesity is defined in the statement as a BMI of at least 35kg/m2 or a BMI that is equal to or greater than 120 percent of the 95th percentile for age, whichever is lowest.
The authors also recommend that this updated definition be universally applied in clinical and research settings because it better captures the children with the most severe problem.
By this standard, they conclude that 6 percent of 2 to 19-year-old youth have a body mass index (BMI) that falls within the range of severe obesity.
Across all pediatric age groups, about 4 percent of children fall into the severely obese category. It's slightly more common among boys than girls and among Hispanics and blacks compared to whites, they report in the journal Circulation.
Children in this group are at risk for the same serious health problems that plague obese adults, including cardiovascular problems, such as high cholesterol and high blood pressure, insulin resistance, prediabetes and sleep apnea. They're also prone to muscle and joint disorders as well as psychosocial problems, the authors point out.
Dr. Stephen Pont, who was not involved in the heart association statement, added that depression, anxiety and liver cirrhosis are other associated health risks that are not often thought about as readily as high blood pressure or high cholesterol.
"Obesity is now becoming the number one cause of liver cirrhosis and liver failure (in kids)," he told Reuters Health.
The good news, he said, is that severely obese children are not necessarily destined to become severely obese adults.
"Obesity, once you have it, is not a fixed condition; it's potentially reversible," said Pont, who is the chair of the American Association of Pediatrics' Section on Obesity.
Current treatment options include lifestyle modification and behavioral therapy, with family-based behavior weight management recommended as first-line treatment.
Such programs have shown modest success, but they may not have lasting effects among severely-obese youth and may not be widely available or affordable to many, the statement authors note.
Medications, including the antidiabetes drugs metformin and exenatide (marketed as Byetta, Bydureon), appear to be promising options but neither of these medications is approved by the U.S. Food and Drug Administration (FDA) for the treatment of obesity in children. The only medication that is FDA approved for use in kids is orlistat (Alli, Xenical), which blocks absorption of fats from food.
Bariatric surgery, also known as gastric bypass, although highly effective, cannot be widely recommended because of its risk of complications, and unknown long-term effects among children and adolescents, the report states.
Other potential treatment options exist, such as the newer medications that have been approved to treat obesity in adults and various bariatric surgery techniques, but they require additional studies to be conducted in pediatric populations.
"There's no silver bullet," Pont said. "Part of the solution is working with doctors and the other part is working (with patients) where they live," he said, citing a need for "advocates for healthy community change."
Referring to the AHA statement as a "call to action," Kelly added, "we're calling on funding agencies to step up and make it a priority to invest in solutions to this problem, as far as treatment goes."
"Prevention of severe pediatric obesity is the ultimate goal and ideal outcome," Kelly and his colleagues write, "however, widespread prevention is unlikely to be realized in the near future, and the numerous children and adolescents affected by this condition need safe and effective treatments now."