title: A new approach to test validity and clinical usefulness of the 2013 ACC/AHA guideline on statin therapy: A population-based study.
abstract: BACKGROUND
  The ACC/AHA released a new guideline on the assessment of cardiovascular risk and management of hypercholesterolemia that some controversy exists concerning its usefulness. We examined the clinical usefulness of this guideline in a high incidence population using novel measures.
  
  
  METHODS
  First, we validated the new risk equation in a cohort of 2372 men and 2781 women aged 40-75 years. Then, high risk individuals for cardiovascular diseases (CVDs) were identified according to the ACC/AHA guideline at baseline (as a predictor) and CVD outcomes were detected during a 10-year follow-up. Discrimination of the guideline was quantified and the quality of decisions was evaluated by Net Benefit Fraction index considering the harm, for false-positive, and benefit, for true-positive predictions. Finally, net number needed to treat (NNT) for statin was estimated, using test tradeoff index, in diabetic and non-diabetic subjects.
  
  
  RESULTS
  During follow-up, 726 CVD events including 298 hard CVDs occurred. The equation overestimated the risk by 57% in men and 48% in women. Based on the guideline, 73% of men and 44% of women were eligible for statin therapy. The lowest sensitivity was detected for intensive treatment in non-diabetic subgroups (82% in men and 41% in women; corresponding specificity, 52% and 90% respectively). The guideline had a significant net benefit for both moderate and intensive treatment, which resulted in estimated NNTs ranged 5-55; however, net benefit of intensive therapy was uncertain in non-diabetic women.
  
  
  CONCLUSIONS
  We objectively showed that the ACC/AHA recommendations could be useful in our population but with some overtreatment in women.
authors.affiliation: Prevention of Metabolic Disorders Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Department of Epidemiology, School of Public Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Davood
authors.initials: D
authors.lastname: Khalili
authors.affiliation: Prevention of Metabolic Disorders Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Samaneh
authors.initials: S
authors.lastname: Asgari
authors.affiliation: Prevention of Metabolic Disorders Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Electronic address: fzhadaegh@endocrine.ac.ir.
authors.forename: Farzad
authors.initials: F
authors.lastname: Hadaegh
authors.affiliation: Department of Public Health, Erasmus MC, Rotterdam, The Netherlands.
authors.forename: Ewout W
authors.initials: EW
authors.lastname: Steyerberg
authors.affiliation: The George Institute for Global Health, University of Oxford, Oxford, United Kingdom.
authors.forename: Kazem
authors.initials: K
authors.lastname: Rahimi
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Noushin
authors.initials: N
authors.lastname: Fahimfar
authors.affiliation: Endocrine Research Center, Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Fereidoun
authors.initials: F
authors.lastname: Azizi
mesh_terms: D000328:Adult; D000368:Aged; D000572:American Heart Association; D002309:Cardiology / Q000592:standards*; D002318:Cardiovascular Diseases / Q000139:chemically induced / Q000188:drug therapy / Q000453:epidemiology; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D011159:Population Surveillance / Q000379:methods; D017410:Practice Guidelines as Topic / Q000592:standards*; D011446:Prospective Studies; D015203:Reproducibility of Results; D012307:Risk Factors; D014481:United States / Q000453:epidemiology
chemical_list: D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors
keywords: Cardiovascular diseases; Net benefit; Number needed to treat; Prevention; Statins