A fascinating article (Gooding HC et al. JAMA Pediatr doi:10.1001/jamapediatrics.2015.0168) studies a cross-sectional analysis of the National Health and Nutrition Examination Survery (NHANES) population and determines the frequency of the need for statin therapy for hyperlipidemia based on two separate guidelines.
- 2011 Integrated Guidelines for Cardiovascular Health and Risk Reduction in Children and Adolescents of the National Heart, Lung, and Blood Institute (Pediatrics 2011; 128 (sup 5): S213-S256) PEDS RECS
- 2013 Guidelines on the Treatment of Blood Cholesterol to Reduce Atherosclerotic Cardiovascular Risk in Adults from the American College of Cardiology and American Heart Association (Circulation 2014: 129 (25) (supl 2) S1-S45) ADULT GUIDELINES
Specifically, the design of the study focused on 17-21 year olds in which the guidelines had overlapping recommendations. While the NHANES population involved only 6338 patients, this representative sample was used to calculate the likelihood of statin therapy more broadly among the US population of 20.4 million in this age group.
- Among the cohort of 6338, 2.5% would qualify for statin treatment using PEDS RECS compared with 0.4% under ADULT GUIDELINES.
- This finding extrapolates to 483,500 patients nationwide compared with 78,200, respectively. This is a difference of more than 400,000 and reflects a 6-fold difference.
Why the discrepancy?
- ADULT GUIDELINES recommend use of statins only if LDL-C is >190. PEDS RECS extend to as low as 130 or 160 if additional risk factors (highly prevalent) are present, including hypertension, obesity, and smoking.
- ADULT GUIDELINES are based on randomized clinical trials, though “they advocate for physician’s judgement in areas where the evidence base is insufficient.” PEDS RECS use extrapolated evidence for lifetime risk of coronary vascular disease.
Bottomline: While these guidelines highlight differences among 17-21 year olds, the decision regarding statin therapy extends across the age spectrum in terms of whether a low or high threshold should be in place. Also, it is unfortunate that the additional modifiable risk factors (smoking, hypertension, and obesity) are so prevalent as to create this divergence in approach.
- NEJM 2015; 372: 1489-99. Alirocumab, a monoclonal antibody that inhibits PCSK9, lowered LDL 62% in patients receiving maximal statin therapy. Randomized, placebo-controlled study with 2341 patients.
- NEJM 205; 372: 1500-09. Evolocumab, a monoclonal antibody that inhibits PCSK9, lowered LDL 61% in two open-label randomized trials (n=4465).
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