TUESDAY, July 13 (Health.com) — Cholesterol tests may soon become as routine a part of childhood health care as vaccines. In recent years, a growing number of pediatricians have been pushing for all children to have their cholesterol checked, not just those who appear to be at risk for heart disease later in life.
Supporters of this controversial proposal have some fresh ammunition. A study published on Monday in the journal Pediatrics suggests that testing only children who have a family history of high cholesterol or heart disease, as government guidelines now recommend, misses roughly one-third of kids with high cholesterol.
The study included more than 20,000 fifth graders in West Virginia, 29% of whom did not have red flags due to family history and would not have been screened under government guidelines. Ten percent of those children were found to have high cholesterol, however, and nearly 2% had levels high enough to make them candidates for cholesterol-lowering drugs.
"Our data suggests that if you were to follow the [existing] recommendation, you would miss 36% of children who have significant and quite elevated cholesterol levels," says William Neal, MD, the senior author of the study and a professor of pediatrics at West Virginia University, in Morgantown.
Levels of bad cholesterol (known as LDL), a primary culprit in heart disease, are considered elevated above 160 mg/dL, "a point where one would at least consider using a cholesterol-lowering medication," Dr. Neal adds.
The findings have refueled a long-running debate on the appropriate level of cholesterol screening in kids. Some pediatricians, like Dr. Neal, believe that all children should receive cholesterol tests as a matter of course, but others worry that this so-called universal screening won't have a tangible impact on heart disease rates and could lead to the overuse of statins and other cholesterol-lowering drugs in kids.
Drug companies appear to view children as a growing market for statins. The European Union recently approved a chewable, child-friendly version of the statin Lipitor for use in children 10 years and older. Regular Lipitor has already been approved in the U.S. for the same age group.
Next page: The role of childhood obesity
The ongoing reevaluation of cholesterol screening is largely a result of the worsening childhood obesity epidemic.
In the early 1990s, the government-run National Cholesterol Education Program (NCEP) recommended cholesterol screening only for children with a family history of heart disease or high cholesterol. The main objective of these guidelines—the ones used in the West Virginia study—was to identify children with genetic conditions that put them at increased risk of developing heart disease relatively early in life, says Patrick McBride, MD, a cardiologist and professor of family medicine at the University of Wisconsin-Madison who helped draft the guidelines.
Since then, however, the obesity rate has doubled among children and tripled among adolescents, creating "a whole new level of risk," Dr. McBride says.
Elaine Urbina, MD, the director of preventive cardiology at Cincinnati Children's Hospital Medical Center, says that the cholesterol picture among children has indeed taken a turn for the worse. "We're seeing a lot more kids with mild elevation of LDL cholesterol but also elevation in triglycerides and low HDL cholesterol, which is . . . related to obesity and insulin resistance," she says. (HDL is the so-called "good" cholesterol, while triglycerides, a type of blood fat, are the third component of a person's total cholesterol number.)
In 2008, in response to these alarming developments, the American Academy of Pediatrics (AAP)—the publisher of Pediatrics—recommended cholesterol screening for children as young as 2 years old who were overweight or obese or who had diabetes, in addition to those with a family history.
The AAP caused a stir by further suggesting that cholesterol-lowering medications might be given to children ages 8 and up with LDL over 190 mg/dL for whom diet changes and exercise weren't working. (The NCEP guidelines had made a similar recommendation, but the panel specifically discouraged the use of statins, which hadn’t yet been studied extensively in minors.)
Now, Dr. Neal and his colleagues are suggesting that each and every child be tested for cholesterol. Critics of universal screening say that the long-term benefits of cholesterol screening—and especially statin use—in kids are unproven, however.
The West Virginia study "addresses the question that guidelines may not capture 100% of children with high cholesterol, but it in no way, shape, or form addresses the real question," says Steven Lipshultz, MD, the chair of pediatrics at the University of Miami's Miller School of Medicine. "Will identifying these patients [and] committing them to long-term—perhaps lifetime—medication ultimately reduce cardiovascular disease?"
Next page: Cholesterol isn't the only important thing
Dr. Lipshultz fears that the growing emphasis on cholesterol screening and statins will distract doctors, parents, and kids from eating healthier food and getting more exercise. High bad cholesterol is just one risk factor for heart disease (albeit an important one), and many children and adolescents already have three or more risk factors for the disease, he points out.
"It's the global risk and the components of that [are] important, not just lowering LDL," Dr. Lipshultz says. "If you wind up giving a child a statin . . . it's unclear whether that's going to make a difference."
The U.S. Preventive Services Task Force, an independent panel of experts that advises the federal government on preventive care, reached a similar conclusion in a 2007 report. The evidence for and against widespread screening wasn't strong enough to make a recommendation either way, the task force stated.
Moreover, Dr. Lipshultz says, the cumulative cost of putting hundreds of thousands of children on statins would become "incredible."
The cost argument is misguided, says Dr. Urbina, who is in favor of universal screening. "The burden to society for paying for someone to have a heart attack and be in the intensive-care unit is much higher than the cost of doing screening," she says.
Dr. McBride, who also supports universal screening, says simply that the new study shows that "universal screening does work and selective screening doesn't work."
Whether more screening and statin prescriptions will reduce heart disease rates as kids grow into adults remains an open question. A large government-sponsored study has begun to gather evidence, but the matter isn't likely to be settled for decades.
In the meantime, the National Institutes of Health has convened a panel of experts to come up with new screening guidelines. The guidelines have been written, but the release date is uncertain, says Dr. Urbina, who served on the panel alongside Dr. McBride.
Although neither doctor is at liberty to reveal the revamped guidelines, Dr. Urbina would say that the committee did not reach "100% agreement" on the merits of universal screening.