Critics at odds with AAP on how to cut kids' heart disease risk

As data accumulate indicating that vascular disease starts decades before it becomes apparent in the form of a heart attack or stroke, physicians who treat children are increasingly looking for ways to start reducing this risk at an early age.

"We have a tremendous epidemic of obesity, and a lot of these kids now have type 2 diabetes. What is the best way to manage them?" asked Myles Abbott, MD, a board member of the American Academy of Pediatrics, although he was speaking personally.

To help answer that question, the AAP's Committee on Nutrition issued a clinical report about lipid screening and cardiovascular health during childhood in the July Pediatrics. The document emphasized lifestyle interventions at both the population and individual levels. It also advocated cholesterol screening for those at increased lifetime risk of cardiovascular disease.

The National Heart, Lung, and Blood Institute's Pediatric Cardiovascular Risk Reduction Initiative is working on its own set of guidelines due out early next year.

"I would like to see [AAP's guidelines] achieve a reasoned and rational approach to this whole area. Hopefully they will raise attention about risk factors for cardiovascular disease in general. These risk factors certainly occur in childhood and may be clustering in families," said Stephen R. Daniels, MD, PhD, the first author on the AAP guidelines. He also chairs the NHLBI's expert panel.

But starting to address the risk for a disease that most likely will not appear for decades is not without controversy. The AAP document urged that those age 8 or older with an LDL higher than 190 mg/dL be considered as possible candidates for cholesterol-lowering medication. Physicians seeing those whose levels are at 160 mg/dL with a family history or more than two other risk factors, or a level of 130 mg/dL and diabetes also should contemplate this intervention, it suggested.

The idea unleashed a firestorm of criticism. Several drugs are approved for this purpose in children and adolescents, but critics charge that data are too limited on their long-term efficacy and safety to make any recommendations that may expand their use.

"The guidelines are based on expert opinion, and they don't have the level of evidence to support them that I would like to see," said Thomas B. Newman, MD, MPH, professor of epidemiology, biostatistics and pediatrics at the University of California, San Francisco. "We don't know at what level of cholesterol and what age the benefits of medication exceed the risks and costs. We don't know what it means to be on these medications for decades, and we don't know whether there's an advantage to starting this young versus starting as an adult."

Concern also was expressed about the influence of possible conflicts of interest because the AAP's Friends of the Children Fund and several members of the panel received some funding from companies that manufacture these medications.

Those behind the guidelines, however, say the conflict of interest is less than perceived. Dr. Daniels said he has consulted Abbott Labs and Merck & Co. Inc., but not on cholesterol-lowering medications. Several committee members had no conflicts to report. "The Committee on Nutrition really has few relationships that would cause a conflict of interest, and the ones that exist are pretty minor," said Dr. Daniels, who also is the pediatrician-in-chief at the Children's Hospital in Aurora, Colo.

The committee also says available research supports this approach and that the studies that may answer the question conclusively would take too long and are unlikely ever to be attempted.

"We have to take the evidence as it exists. ... Some of the kinds of evidence that we would like, such as a direct decrease of myocardial infarction in adults, those studies would take 30 or 40 years. I think they are very unlikely to ever be done," Dr. Daniels said.

Many experts say the new guidelines do not expand statin use in children by very much and are not that different from the ones issued by the AAP about a decade ago or those from other organizations.

For instance, American Heart Assn. recommendations that were published April 10, 2007, in Circulation advised considering starting drug therapy at age 10. Cholesterol levels that would indicate a need to consider medication have been set high deliberately to capture the small number of children who most likely have a genetic condition that raises their cholesterol.

"They are a lot less different than people seem to be giving them credit for," said Samuel Gidding, MD, chief of pediatric cardiology at the Nemours/Alfred I. duPont Hospital for Children in Wilmington, Del. He also is a member of NHLBI's expert panel on this subject. "The main difference is the age at which treatment could start, but the number of children who would need treatment is extremely small. The recommendation really applies to a very select subgroup of children who are at extreme risk for premature heart disease."

Critics, though, would like to see less of a focus on cholesterol and more of an emphasis on the many factors, such as tobacco use or diet, that come together to increase cardiovascular disease risk. The guidelines due from NHLBI are expected to do just that.