New cholesterol guidelines urged for adolescents
■ Experts say it's important to identify early those at high risk of heart disease, but some say teens have more pressing issues.
By Victoria Stagg Elliott — Posted Oct. 16, 2006
A crystal ball to predict high cholesterol? Not exactly.
But, according to a paper published in the Sept. 5 Circulation, improvements in the current risk-calculation system could enable physicians to detect better who among their teenage patients may be headed for cardiovascular disease later in life. The guiding principles would be age- and gender-specific cholesterol standards.
Although cholesterol fluctuates throughout childhood and adolescence, current definitions of high levels, based on the National Heart Lung and Blood Institute's National Cholesterol Education Program, are the same whether a child is 2 years old or 17, male or female.
"The goal is to better identify the people who are at risk and be able to put a special emphasis on changing their lifestyle," said Ian Janssen, PhD, senior author and assistant professor in the Dept. of Community Health and Epidemiology at Queen's University in Kingston, Ontario.
In general, the study outlines a new set of healthy cholesterol numbers derived from data from the Centers for Disease Control and Prevention's National Health and Nutrition Examination Surveys.
Response was mixed. Some praised the efforts to more precisely determine teenagers' normal cholesterol ranges, saying a tool based on this information could complement similar growth curve mechanisms already in use for weight and height.
"It would be useful to have cholesterol curves just like height, weight and body mass index curves, and have them all tied together," said Irwin Benuck, MD, PhD, a pediatrician at Children's Memorial Hospital in Chicago.
Others found the data intriguing but doubted such a cholesterol curve would be clinically useful, primarily because a few points in either direction make little difference over the long term. Also, these cutoffs were determined by age rather than physical development, which can vary widely.
"It's nice to see the variation," said Christiane Stahl, MD, an adolescent medicine specialist at the University of Illinois, Chicago. "But I don't think clinicians will embrace it."
But although there is debate about how useful a cholesterol growth chart would be, there is significant agreement that related guidelines are in desperate need of revision. The NCEP last issued recommendations for adolescents in 1992. The American Academy of Pediatrics policy, largely based on those recommendations, followed in January 1998 but was retired in May. The NCEP plans to convene an expert panel this fall and, over the next two years, develop new guidelines for cholesterol and other heart disease risk factors for children and adolescents.
"There's been a lot of research, and kids have gotten a lot fatter," said Samuel Gidding, MD, attending cardiologist at the Alfred I. duPont Hospital in Wilmington, Del. He wrote the editorial accompanying Dr. Janssen's paper. "We have a different set of public health circumstances now. When kids were leaner, triglycerides and cholesterol didn't matter as much."
Work on this subject is a vital path to early intervention, as research continues to reveal that heart disease starts not just years but decades before it becomes apparent. Many physicians also say a cholesterol number can open the door to much larger discussions about healthy lifestyles, particularly with the increasing number of obese teens.
"It creates a dialogue with kids, and they take some ownership in interpreting the numbers," Dr. Benuck said. "Looking at kids can also be a back door to looking at their parents. If a child has high cholesterol, I can almost guarantee the parents will, too."
Still, while some experts debate what is a healthy cholesterol value for kids and teens and gear up to write new guidelines, measurements are also not without controversy. Some physicians question whether it is necessary to intervene quite so early and whether new guidelines are necessary at all. Adolescents are rarely directly harmed by their cholesterol levels, and some doctors suggest they may have more immediate health concerns.
"This study gives the right answer to the wrong question," said Thomas Newman, MD, MPH, professor of epidemiology, biostatistics and pediatrics at the University of California, San Francisco. "There's so much more important stuff that doctors can be talking to [teenagers] about than cholesterol."