title: Using the coronary artery calcium score to guide statin therapy: a cost-effectiveness analysis.
abstract: BACKGROUND
  The coronary artery calcium (CAC) score predicts future coronary heart disease (CHD) events and could be used to guide primary prevention interventions, but CAC measurement has costs and exposes patients to low-dose radiation.
  
  
  RESULTS
  We estimated the cost-effectiveness of measuring CAC and prescribing statin therapy based on the resulting score under a range of assumptions using an established model enhanced with CAC distribution and risk estimates from the Multi-Ethnic Study of Atherosclerosis. Ten years of statin treatment for 10,000 55-year-old women with high cholesterol (10-year CHD risk, 7.5%) was projected to prevent 32 myocardial infarctions, cause 70 cases of statin-induced myopathy, and add 1108 years to total life expectancy. Measuring CAC and targeting statin treatment to the 2500 women with CAC>0 would provide 45% of the benefit (+501 life-years), but CAC measurement would cost $2.25 million and cause 9 radiation-induced cancers. Treat all was preferable to CAC screening in this scenario and across a broad range of other scenarios (CHD risk, 2.5%-15%) when statin assumptions were favorable ($0.13 per pill and no quality of life penalty). When statin assumptions were less favorable ($1.00 per pill and disutility=0.00384), CAC screening with statin treatment for persons with CAC>0 was cost-effective (<$50 000 per quality-adjusted life-year) in this scenario, in 55-year-old men with CHD risk 7.5%, and in other intermediate risk scenarios (CHD risk, 5%-10%). Our results were critically sensitive to statin cost and disutility and relatively robust to other assumptions. Alternate CAC treatment thresholds (>100 or >300) were generally not cost-effective.
  
  
  CONCLUSIONS
  CAC testing in intermediate risk patients can be cost-effective but only if statins are costly or significantly affect quality of life.
authors.affiliation: Department of Epidemiology and Biostatistics.
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Pletcher
authors.forename: Michael
authors.initials: M
authors.lastname: Pignone
authors.forename: Stephanie
authors.initials: S
authors.lastname: Earnshaw
authors.forename: Cheryl
authors.initials: C
authors.lastname: McDade
authors.forename: Kathryn A
authors.initials: KA
authors.lastname: Phillips
authors.forename: Reto
authors.initials: R
authors.lastname: Auer
authors.forename: Lydia
authors.initials: L
authors.lastname: Zablotska
authors.forename: Philip
authors.initials: P
authors.lastname: Greenland
mesh_terms: D000924:Anticholesteremic Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000191:economics*; D002118:Calcium / Q000097:blood*; D003198:Computer Simulation; D003327:Coronary Disease / Q000175:diagnosis* / Q000517:prevention & control; D003331:Coronary Vessels / Q000378:metabolism / Q000528:radiation effects; D003362:Cost-Benefit Analysis; D003658:Decision Making, Computer-Assisted; D054796:Drug Dosage Calculations; D005260:Female; D006801:Humans; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors / Q000008:administration & dosage / Q000009:adverse effects / Q000191:economics*; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D009135:Muscular Diseases / Q000209:etiology; D011322:Primary Prevention; D011839:Radiation, Ionizing; D014057:Tomography, X-Ray Computed
chemical_list: D000924:Anticholesteremic Agents; D019161:Hydroxymethylglutaryl-CoA Reductase Inhibitors; D002118:Calcium
keywords: atherosclerosis; calcium; coronary artery disease; economics; statins, HMG-CoA