title: Effect of aspirin and NSAIDs on risk and survival from colorectal cancer.
abstract: BACKGROUND
  Previous studies have shown that aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs) lower colorectal cancer (CRC) risk. However, the lowest effective NSAID dose, treatment duration, and effects on survival are not defined. In a large population-based case-control study, we have explored the relationship between NSAID dose and duration, CRC risk and overall CRC-specific survival.
  
  
  METHODS
  The relationship between NSAID use and CRC risk was examined in 2279 cases and 2907 controls. Subjects completed food-frequency and lifestyle questionnaires. NSAID categories were low-dose aspirin (75 mg), non-aspirin NSAIDs (NA-NSAIDs) and any NSAID. Users were defined as taking >4 tablets/week for >1 month. ORs were calculated by logistic regression models and adjusted for potential confounding factors. Effect of NSAID use on all-cause and CRC-specific mortality was estimated using Logrank tests and Cox's hazard models.
  
  
  RESULTS
  In all, 354 cases (15.5%) were taking low-dose aspirin compared to 526 controls (18.1%). Low-dose aspirin use was associated with decreased CRC risk (OR 0.78 95% CI 0.65 to 0.92, p=0.004), evident after 1 year and increasing with duration of use (p(trend)=0.004). NA-NSAID and any NSAID use were also inversely associated with CRC. There was no demonstrable effect of NSAIDS on all-cause (HR 1.11, p=0.22, 0.94-1.33) or CRC-specific survival (HR 1.01, p=0.93, 0.83-1.23).
  
  
  CONCLUSIONS
  This is the first study to demonstrate a protective effect against CRC associated with the lowest dose of aspirin (75 mg per day) after only 5 years use in the general population. NSAID use prior to CRC diagnosis does not influence survival from the disease.
authors.affiliation: Colon Cancer Genetics Group and Academic Coloproctology, Institute of Genetics and Molecular Medicine, University of Edinburgh and MRC Human Genetics Unit, Western General Hospital, Edinburgh EH4 2XU, UK.
authors.forename: Farhat V N
authors.initials: FV
authors.lastname: Din
authors.forename: Evropi
authors.initials: E
authors.lastname: Theodoratou
authors.forename: Susan M
authors.initials: SM
authors.lastname: Farrington
authors.forename: Albert
authors.initials: A
authors.lastname: Tenesa
authors.forename: Rebecca A
authors.initials: RA
authors.lastname: Barnetson
authors.forename: Roseanne
authors.initials: R
authors.lastname: Cetnarskyj
authors.forename: Lesley
authors.initials: L
authors.lastname: Stark
authors.forename: Mary E
authors.initials: ME
authors.lastname: Porteous
authors.forename: Harry
authors.initials: H
authors.lastname: Campbell
authors.forename: Malcolm G
authors.initials: MG
authors.lastname: Dunlop
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage / Q000627:therapeutic use*; D016588:Anticarcinogenic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001241:Aspirin / Q000008:administration & dosage / Q000627:therapeutic use*; D015179:Colorectal Neoplasms / Q000453:epidemiology / Q000517:prevention & control*; D015986:Confounding Factors, Epidemiologic; D004032:Diet / Q000706:statistics & numerical data; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D008019:Life Style; D008297:Male; D008875:Middle Aged; D011203:Poverty / Q000706:statistics & numerical data; D012606:Scotland / Q000453:epidemiology; D012907:Smoking / Q000453:epidemiology; D055815:Young Adult
chemical_list: D000894:Anti-Inflammatory Agents, Non-Steroidal; D016588:Anticarcinogenic Agents; D001241:Aspirin