Twenty percent of young people aged 12-19 years in the U.S. have at least one abnormal lipid level, according to a study from the Centers for Disease Control and Prevention (CDC). Abnormal lipid levels are major risk factors for heart disease, the leading cause of death among adults in the U.S.

The report, “Prevalence of Abnormal Lipid Levels among Youths —United States, 1999–2006,” was published today in CDC’s Morbidity and Mortality Weekly Report (MMWR).

The report examined data for 1999–2006 from the National Health and Nutrition Examination Survey (NHANES), an ongoing study that explores the health and nutritional status of about 6000 participants every year. Researchers analyzed measurements of low-density lipoprotein, or “bad,” cholesterol (LDL-C); high-density lipoprotein, or “good,” cholesterol (HDL-C); and triglycerides.

The researchers found that young people who were overweight or obese were more likely to have one or more abnormal lipid levels compared to normal weight youth. Fourteen percent of normal weight, 22 percent of overweight, and 43 percent of obese youth had one or more abnormal lipid levels.

The study also found that 32 percent of these young people would be candidates for lipid screening based on American Academy of Pediatrics (AAP) guidelines. The AAP recommends lipid screening for young people with a family history of high blood cholesterol or premature cardiovascular disease, or the presence of at least one major risk factor for heart disease, such as smoking, high blood pressure, diabetes, or overweight/obesity.

Reviewing health indicators for 3125 youths, researchers found that differences in lipid levels were associated with sex, age, and race/ethnicity. Specifically:

• More boys (24%) than girls (16%) had at least one abnormal lipid level.
• Fourteen- and 15-year-olds (9%) and 18- and 19-year-olds (10%) were more likely to have low HDL cholesterol levels than 12- and 13-year-olds (5%).
• Non-Hispanic white youths were more likely to have low levels of HDL cholesterol (8%) and high triglycerides (12%), compared to non-Hispanic black youths (5% and 4%, respectively).

Typically, heart disease develops in adulthood. But its risk factors, such as abnormal lipid levels and overweight/obesity often emerge during childhood and adolescence.

“Overweight and obese young people are at far greater risk of having abnormal lipid levels than are youths with normal weights,” said Ashleigh May, PhD, Epidemic Intelligence Service Officer in CDC’s Division for Heart Disease and Stroke Prevention, and lead author of the report. “The current epidemic of childhood obesity makes this a matter of significant and urgent concern.”

In the past three decades, obesity among American youths has increased from 5% to more than 17%. In light of this, the study’s authors suggested that clinicians should be aware of guidelines for lipid screening and treatment among youths.