Does Cholesterol Screening Do More Than Stigmatize Children?

OPINION by DR. NORTIN HADLER

The American Academy of Pediatrics (AAP) has just issued guidelines for cardiovascular risk reduction in children and adolescents. I have grave reservations about the recommendation in the guidelines for “universal” lipid screening at age 9.

This is a recommendation that targets youngsters who are well and whose family history does not suggest a hereditary disease of lipid metabolism. That’s nearly all children. Screening is a wonderful idea, but — as has become painfully clear in recent years — it is difficult to carry out in a way that benefits the individual, let alone the general public.

To be beneficial, any screening test must be accurate, the disease sought must be important and, if found, we must be able to do something about it. Effective screening for lipid abnormalities, such as cholesterol, is particularly challenged by all three criteria:

  • Firstly, cholesterol is not a disease; it is a normal and essential body constituent. Yes, the blood level correlates with incremental risk of developing atherosclerosis (hardening of the arteries), but the increment in risk is far from dramatic. Therefore, one is screening for a surrogate of atherosclerosis, not the disease itself, and not a particularly accurate surrogate.
  • Secondly, atherosclerosis is a disease of aging. It can be viewed as graying of our arteries. We know that the graying starts in the 20s in men, including in the majority of men who are now enjoying a degree of longevity that their father’s generation considered exceptional. These men, too, will die, often from the consequences of atherosclerosis, but decades later than their father’s generation. The goal for the health of the public is not to prevent atherosclerosis but to prevent its consequences before one arrives at a ripe old age. Only a few are so fated and cholesterol level is a woefully inadequate way to spot them.
  • Thirdly, the guideline panel is recommending universal screening based on scientific evidence that it considers sufficient. That is an overstatement pertaining to adults; it is a gross overstatement when it comes to universal screening benefiting a child who is labeled as having high cholesterol. It has been exceedingly difficult to demonstrate that lowering the cholesterol of adults who are otherwise well actually does anything for their well-being. The Cochrane collaboration recently reviewed this data, concluding, “Caution should be taken in prescribing statins for primary prevention among people at low cardiovascular risk.”  I do not share the temerity of the Pediatric Expert Panel in its willingness to throw such caution to the wind.

Clinical guidelines and the expert panels that draft them have come under considerable criticism in the past couple of years. Some guideline panels rely simply on the collective judgment of the panel members. Many attempt a detailed review of the scientific literature and cull those studies that are deemed sound enough to be informative.

This is the principle of evidence-based medicine and is the exercise undertaken by the American Academy of Pediatrics’ panel. If they had come across scientific studies that are methodologically sound with results that are consistent and compelling, they would have offered a “strong recommendation.” If there was no informative science, only opinions, they would have offered “no recommendation.” In between is the scientific evidence that can’t be ignored but is considered too lacking in quality to be compelling. If the evidence is deemed more persuasive, it is “recommended”; less persuasive and it’s deemed “optional.” That’s what the AAP panel means by its “recommendation” for universal lipid screening at age 9.

Realize the difference between “recommended” and a lesser rating of “optional” relies on “a consensus of the expert panel.” This judgment is heavily value laden.

Many of the more influential clinical guidelines have been drafted by thought leaders who have active, considerable and stated financial relationships with pharmaceutical firms and other entities that stand to gain substantially if the recommendations are followed. That is the case for the Pediatric Guidelines Panel; only six of the 14 members denied such relationships.

Last March, a committee of the Institute of Medicine of the National Academies issues a report titled, “Clinical Practice Guidelines We Can Trust,” dissecting and decrying the influence of conflicts of interest on the content of guidelines. For example, guidelines put forth by successive expert panels of the American College of Cardiology/American Heart Association have shifted from considering the same or similar evidence that once was worthy of the “optional” rating to now be worthy of a “recommended” rating. This caused Terrence Shaneyfelt and Robert Centor to assert in a 2009 article in the Journal of the American Medical Association that “too many current guidelines have become marketing and opinion-based pieces, delivering directive rather than assistive statements.”

“So what?” you might ask. “Shouldn’t we screen these children and treat many so we can be safe rather than sorry?”

But there are downsides. One relates to the rare catastrophic muscle disease and common musculoskeletal discomfort that plagues treatment in adults, not to mention fears about cataracts and diabetes. But more predictable is “negative labeling.” We will be taking children who feel well, even invincible, and laying on the notion that they have a time-bomb on board, a metabolic blight threatening their future. If that doesn’t weigh heavily on the child, it will on the parent. By what science, and by what right, can we be guided to do that.

I discuss much of this in great detail as it relates to adults in two of my recent books:

*** Dr. Nortin Hadler is professor of medicine and microbiology/immunology at the University of North Carolina at Chapel Hill, and an attending rheumatologist at University of North Carolina Hospitals.