Study highlights:
• Less than 1 percent of U.S. adolescents have cholesterol levels high enough to potentially qualify for cholesterol-lowering drugs.
• Researchers found elevated levels of “bad” cholesterol in up to 6.6 percent of adolescents, and up to 10.7 percent had high total cholesterol.
• Researchers said these numbers establish a baseline for assessing and monitoring the cholesterol levels of U.S. adolescents and how those levels might impact future cardiovascular disease risk.

DALLAS, Feb. 16, 2009 — While some experts have recently recommended more aggressive cholesterol screening in childhood, less than 1 percent of adolescents 12–17- years-old may potentially qualify for cholesterol-lowering drugs, according to a new study published in Circulation: Journal of the American Heart Association.

According to the study, updated recommendations for cholesterol screening in childhood released last year by the American Academy of Pediatrics (AAP) has drawn new attention to the importance of healthy cholesterol concentrations in children and adolescents.

“I think the new recommendations caused a lot of people to be concerned about children having high cholesterol and being put on medications for a good part of their lives,” said Earl S. Ford, M.D., M.P.H., lead author of the study and medical officer in the United States Public Health Service. “In this study we set out to produce numbers so we would know exactly what we are talking about in terms of the percentages of U.S. children who may need to be treated or may have high cholesterol levels.”

Ford and colleagues studied the National Health and Nutrition Examination Survey 1999 to 2006, a database of health information, including cholesterol levels, for a national sample of people of all ages.
 
The researchers reviewed information on nearly 10,000 participants ages 6 to 17, including about 2,700 adolescents ages 12 to 17 who had fasting low density lipoprotein (LDL) levels measured.
Researchers found:
• The average LDL level was 90.2 milligrams per deciliter (mg/dL) and the average total cholesterol was 163 mg/dL — both considered acceptable levels.
• Total cholesterol levels were 3.6 mg/dL higher in girls compared to boys.
• Total cholesterol levels were 2.6 mg/dL higher among African Americans and 1.9 mg/dL lower among Mexican Americans when compared with whites.
• The higher concentrations of total cholesterol for girls start to emerge around age 14.
The AAP guidelines suggest that cholesterol drugs, or statins, be considered for children as young as 8-years-old, if a screening shows their cholesterol levels are at or above accepted levels.

For example, cholesterol drugs, or statins may be considered for children who have:
• no other risk factors for cardiovascular disease and cholesterol levels greater than 190 mg/dL;
• other risk factors present including obesity, hypertension, or cigarette smoking or positive history of premature cardiovascular disease and cholesterol levels greater than 160 mg/dL; or
• diabetes with cholesterol levels equal to or greater than130 mg/dL.

Based on approaches presented in the AAP guidelines to define elevated concentrations of LDL and total cholesterol by age and gender, researchers found 5.2 percent to 6.6 percent of adolescents had an elevated concentration of LDL cholesterol and 9.6 percent to 10.7 percent had elevated total cholesterol.

However, when researchers calculated how many of these adolescents were eligible for pharmacologic management of their cholesterol, based on AAP established guidelines, they found 0.8 percent or 200,000 adolescents ages 12 to 17 were potentially eligible.

“It is a matter of opinion whether one thinks 0.8 percent is a small or large percentage,” Ford said.

“What I think is most important here is that — given the rise in childhood obesity and risk factors such as smoking and lack of exercise that adolescents are exposed to — we need to continually assess and monitor the lipid status of children and adolescents. Having high cholesterol levels in childhood will affect the future rates of cardiovascular disease among U.S. adults.”

American Heart Association guidelines call for selective screening in children with a family history of high cholesterol and early heart disease, but recommends that the first line of treatment for these children would be lifestyle changes to encourage healthier eating and more physical activity.

Continued research is needed in the area of drug therapy for high-risk cholesterol abnormalities in children, particularly research on its long-term efficacy, safety and impact on the atherosclerotic disease process, Ford said.

Co-authors are: Chaoyang Li, M.D., Ph.D.; Guixiang Zhao, M.D., Ph.D.; and Ali H. Mokdad, Ph.D. Individual author disclosures are available on the manuscript.

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Statements and conclusions of study authors that are published in American Heart Association scientific journals are solely those of the study authors and do not necessarily reflect the association’s policy or position. The association makes no representation or guarantee as to their accuracy or reliability. The association receives funding primarily from individuals; foundations and corporations (including pharmaceutical, device manufacturers and other companies) also make donations and fund specific association programs and events. The association has strict policies to prevent these relationships from influencing the science content. Revenues from pharmaceutical and device corporations are available at www.americanheart.org/corporatefunding. 

NR09 – 1025 (Circ/Ford)