'Just for Teens' Cholesterol Analysis
New System Could Help Spot Risk for Future Heart Disease
Aug. 29, 2006 - A new system for interpreting cholesterol levels in teens
could help better identify those at risk for heart disease
as adults, researchers say.
Unlike the current guidelines, the proposed classification system factors in
an adolescent's age and gender when determining normal and abnormal cholesterol
This is important, says a researcher who developed the new system, because
cholesterol levels are known to change greatly with normal growth, and they
also differ by gender prior to adulthood.
"With the current system, very, very few young children would be
considered at risk, even if they have very high cholesterol
values for their age," Ian Janssen, PhD, tells WebMD. "And girls mature
much earlier than boys. So at age 12 or 13, we might see different values in
females than in males."
Pediatricians do not routinely test cholesterol levels in children and
teens, and adolescents are rarely put on cholesterol-lowering drugs because
they have a low risk for heart disease.
But it is increasingly clear that the buildup of fatty plaque in the
arteries that leads to heart disease can begin in childhood, Janssen says.
Current U.S. guidelines, in place since the early 1990s, have the same
thresholds for identifying abnormal cholesterol and triglyceride levels for all
children and teens between the ages of 2 and 19.
To create the new classification system, Janssen and colleague Courtney
Jolliffe, MSc, of Ontario's Queen's University, Kingston, examined data from
the U.S. National Health and Nutrition Examination Surveys (NHANES) collected
between 1988 and 2002.
They looked at total cholesterol, LDL (bad) cholesterol, HDL (good)
cholesterol, and triglyceride measurements for some 6,000 study participants
between the ages of 12 and 20 to develop age- and gender-specific growth
curves, similar to those used to monitor height and weight.
The New System
Under the new classification, a 12-year-old boy's total cholesterol level
would be considered high at 233 mg/dL or greater, while the corresponding
numbers for 15- and 19-year-old males would be 220 mg/dL and 238 mg/dL,
A 12-year-old girl's total cholesterol would be considered high at 211 mg/dL
or greater, as would a 15-year-old's. The problem number for a 19-year-old
female would be 238 mg/dL or above.
The report is published in the upcoming issue of the American Heart
Association journal, Circulation.
At-Risk Kids Need Screening
Janssen makes it clear he does not think all children and teens need to have
their cholesterol checked. But screening could help predict future risk in
children with a strong family history of early heart disease
or who have other risk factors for future heart disease, such as obesity, diabetes, and high
In this group of children, cholesterol screening using the new
classification may help identify those at future risk better than measuring
blood pressure and body mass index alone, he says.
American Heart Association spokesman Roger Blumenthal, MD, tells WebMD the
new classification may give doctors more ammunition to motivate at-risk teens
to make the dietary and lifestyle changes that could help them avoid future
It could also give doctors a better idea of which patients might need to be
placed on cholesterol-lowering statin drugs in their early 20s, he says.
Blumenthal directs the Johns Hopkins Ciccarone Preventive Cardiology Center
"This should give us a better idea of what normal [cholesterol and
triglyceride] levels are for teenagers," he says. "Physicians can use
this information to help their patients better understand their risks."