Nearly one third of overweight or obese teenagers have the metabolic syndrome, a cluster of disorders that raise the risk of developing heart disease and diabetes, according to a new report.

Dr. Nader Rifai and colleagues at Children’s Hospital in Boston examined data on nearly 2000 children, 12 to 19 years old, who participated in the Third National Health and Nutritional Survey between 1988 and 1994

The team proposed a definition of metabolic syndrome in adolescents based closely on the criteria for adults. Writing in the American Heart Association’s journal Circulation, they say that the subjects had metabolic syndrome if they were positive for at least three heart disease risk factors: high triglycerides, low levels of HDL “good ” cholesterol, high blood sugar levels, a big waist circumference and high blood pressure.

Altogether, 63 percent had at least one metabolic abnormality, and 9 percent could be classified as having the metabolic syndrome. Among subjects above the 85th percentile of body weight for their height, age and gender, the prevalence of metabolic syndrome was 31 percent.

Mexican-American children were affected most, with 13 percent having the metabolic syndrome, followed by non-Hispanic whites at 11 percent and non-Hispanic blacks at 2.5 percent.

Doctors should be on the alert for “the clustering of metabolic abnormalities” in teens, Rifai’s team concludes, “and affected children should receive risk-reducing interventions.”

SOURCE: Circulation, October 19, 2004.