title: Chemoprevention of colorectal cancer by aspirin: a cost-effectiveness analysis.
abstract: OBJECTIVE
  The aim of the study is to compare the cost-effectiveness of aspirin and colonoscopy in the prevention of colorectal cancer.
  
  
  METHODS
  A Markov process is used to follow a hypothetical cohort of 100,000 subjects aged 50 years until death. Four strategies are compared: (1) no intervention, (2) colonoscopy once per 10 years and every 3 years in subjects with polyps, (3) chemoprevention with 325 mg of daily aspirin, and (4) combination of the second and third strategies. The various strategies are compared calculating incremental cost-effectiveness ratios (ICERs).
  
  
  RESULTS
  The expected number of colorectal cancers is 5904 per 100,000 subjects. Colonoscopy prevents 4428 colorectal cancers and saves 7951 life-years at an ICER of $10,983 per life-year saved compared with no intervention. Aspirin prevents 2952 colorectal cancers and saves 5301 life-years at an ICER of $47,249 per life-year saved compared with no intervention. The cost of aspirin therapy plus management of aspirin-related complications was reported to be $172 per year per patient. Varying the annual aspirin-related costs between $50 and $200 results in ICER changes between $4617 and $57,080, with the 2 strategies breaking even at $70. Applying aspirin chemoprevention plus colonoscopy screening concomitantly yields an ICER of $227,607 per life-year saved compared with screening colonoscopy alone.
  
  
  CONCLUSIONS
  As compared with colonoscopy once per 10 years, the use of aspirin to prevent colorectal cancer saves fewer lives at higher costs. The high complication cost and the lower efficacy of aspirin render screening colonoscopy a more cost-effective strategy to prevent colorectal cancer.
authors.affiliation: Department of Veterans Affairs Medical Center, Albuquerque, New Mexico 87108, USA.
authors.forename: Saud
authors.initials: S
authors.lastname: Suleiman
authors.forename: Douglas K
authors.initials: DK
authors.lastname: Rex
authors.forename: Amnon
authors.initials: A
authors.lastname: Sonnenberg
mesh_terms: D000368:Aged; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000191:economics / Q000627:therapeutic use*; D001241:Aspirin / Q000191:economics / Q000627:therapeutic use*; D003113:Colonoscopy; D015179:Colorectal Neoplasms / Q000188:drug therapy / Q000191:economics / Q000517:prevention & control; D003362:Cost-Benefit Analysis; D006801:Humans; D008390:Markov Chains; D008875:Middle Aged
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D001241:Aspirin