Cholesterol controversy

Recent guidelines (Pediatrics 2012; 130: 353-56) have recommended universal screening for hypercholesterolemia between ages 9-11 along with additional targeted screening.  These recommendations have been met with a number of criticisms (Pediatrics 2012; 130: 349-52).

In the first referenced commentary, the experts who issued the guidelines commissioned by the National Heart Lung and Blood Institute (NHBLI) claim that the criticism “misrepresent the evidence regarding screening and the specificity and rigor of the guideline development.”  In the second commentary, the guidelines are considered overly aggressive and not adequately founded on evidence-based medicine.  In addition, they cite two JAMA commentaries that also question the wisdom of the guidelines (JAMA 2012; 307: 257-58, & 259-60).

NHBLI recommendations:

▪  Universal screening of all 9-11 year-olds with a nonfasting lipid panel.

▪  Targeted screening of 2-8 year-olds and 12-16 year-olds with 2 fasting lipid profiles.  The targeted group are for those with diabetes, hypertension, BMI >95%, smoke cigarettes, have a parent with cholesterol >240 (or known dyslipidemia), 1st or 2nd degree relative (includes parents, aunts, uncles, and grandparents) with stroke or coronary artery disease <55 years for men or <65 for women.  According to the critical commentary, 30-40% of children will meet family history criteria and many more will meet other criteria.

▪  If LDL ≥130 mg/dL, then a “CHILD-1” diet is recommended.

▪  Individuals with abnormal screening are to have fasting lipid panels every 6-12 months indefinitely even if their values become acceptable.

Criticisms and responses by guideline authors in italics

▪  While the critics concede that cumulative exposure to high LDL and hypertension increase the risk of cardiovascular disease (CVD), they indicate that with the exception of a small number of individuals (rare homozygous familial hypercholesterolemia) that there is not proof that intervention in childhood is necessary.  The chain of evidence cited by the panel has “notably the absence of even observational evidence or modeling to estimate the clinical event benefits of screening for and intervening on these risk factors in children.”  Atherosclerosis is a lifelong process…Heterozygous familial hypercholesterolemia affects 1:500 and 51% of untreated men develop CV disease events by age 50 years… Accidental death studies (ages 15-30 years) have shown that a 30 mg/dL increase in non-HDL was equivalent to 2 years of vascular aging.  Bogalusa Heart Study showed that number of risk factors correlated with increased atherosclerosis at autopsy after accidental death.  Carotid intima media thickness in adulthood correlates with LDL levels obtained between 12-18 years of age.

▪  No quantification of potential harms such as neuroses, family conflict, CVD anxiety or from medication.  Among children with familial cardiovascular disease, interview studies have shown positive future health perceptions and effective coping.  ‘A study of universal CV risk screening in schools, accompanied by environmental change, showed improvements in healthy lifestyle behaviors and CV risk profiles.’  Risk of statin therapy, (only 0.8% of adolescents would be eligible per authors) has shown no adverse effects in children and adolescents.

The majority of the panel members…disclosed an extensive assortment of financial relationships with companies making lipid-lowering drugs and lipid-testing instruments.  Evidence regarding the efficacy and safety of these medications would not be available without academic partnership with industry.  Potential conflicts of interest were declared and vetted.

▪  Cost/cost-effectiveness. The present policy proposes an intervention applied to a healthy and asymptomatic population, with an enormous impact on costs and the potential to transform well children into patients with a chronic disease label. “Any intervention with nonzero benefit may be recommended, regardless of how much it costs and how much better health might be achieved by investing those resources elsewhere.”  There have been several studies exploring the cost-effectiveness of screening and management strategies for familial hypercholesterolemia (FH). In the Netherlands, a genetic screening program showed that new cases of FH gained 3.3 years of life at an average lifetime cost of US$8700 per year gained.  More complex cost-effectiveness modeling of treatment of children and adolescents has not yet been performed.

So who is right in this debate?

Previous related blog entry:

Cardiovascular disease for the entire family