Accuracy of statin assignment using the 2013 AHA/ACC Cholesterol Guideline versus the 2001 NCEP ATP III guideline: correlation with atherosclerotic plaque imaging.

BACKGROUND: Accurate assignment of statin therapy is a major public health issue.

OBJECTIVES: The American Heart Association and the American College of Cardiology released a new guideline on the assessment of cardiovascular risk (GACR) to replace the 2001 National Cholesterol Education Program (NCEP) Adult Treatment Panel III recommendations. The aim of this study was to determine which method more accurately assigns statins to patients with features of coronary imaging known to have predictive value for cardiovascular events and whether more patients would be assigned to statins under the new method.

METHODS: The burden of coronary atherosclerosis on computed tomography angiography was measured in several ways on the basis of a 16-segment model. Whether to assign a given patient to statin therapy was compared between the NCEP and GACR guidelines.

RESULTS: A total of 3,076 subjects were studied (65.3% men, mean age 55.4 ± 10.3 years, mean age of women 58.9 ± 10.3 years). The probability of prescribing statins rose sharply with increasing plaque burden under the GACR compared with the NCEP guideline. Under the NCEP guideline, 59% of patients with ≥50% stenosis of the left main coronary artery and 40% of patients with ≥50% stenosis of other branches would not have been treated. The comparable results for the GACR were 19% and 10%. The use of low-density lipoprotein targets seriously degraded the accuracy of the NCEP guideline for statin assignment. The proportion of patients assigned to statin therapy was 15% higher under the GACR.

CONCLUSIONS: The new American Heart Association/American College of Cardiology guideline matches statin assignment to total plaque burden better than the older guidelines, with only a modest increase in the number of patients who were assigned statins.