Association between use of low-dose aspirin and detection of colorectal polyps and cancer in a screening setting

Dig Liver Dis. 2023 Aug;55(8):1126-1132. doi: 10.1016/j.dld.2023.01.156. Epub 2023 Feb 6.

Abstract

Background: The possible protective effect of aspirin on risk of colorectal cancer (CRC) is still highly debated.

Methods: We used data from Bowel Cancer Screening in Norway, a trial randomizing individuals from general population, aged 50-74 years, to flexible sigmoidoscopy or faecal immunochemical test (FIT), to study the association between aspirin use and detection of CRC and two CRC precursors: adenomas and advanced serrated lesions (ASL). Prescriptions of low-dose aspirin were obtained from Norwegian prescription database. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs).

Results: Among 64,889 screening participants (24,159 sigmoidoscopy, 40,730 FIT), 314 (0.5%) had CRC, 6,208 (9.6%) adenoma and 659 (1.0%) ASL. Overall and short-term use (<3 years) of low-dose aspirin, versus no use, were not associated with any colorectal lesion. Long-term use (≥3 years) was associated with lower detection of CRC (overall OR 0.66, 95%CI 0.46-0.93; sigmoidoscopy: 0.56, 0.33-0.97; FIT: 0.72, 0.45-1.15), adenomas in sigmoidoscopy arm (overall OR 0.95, 95%CI 0.87-1.03; sigmoidoscopy: 0.89, 0.80-0.99; FIT: 1.03, 0.89-1.18), but not ASLs. We did not observe significant differences in the effect of aspirin according to the location of colorectal lesions.

Conclusion: Our results suggest that long-term use of aspirin might have a protective effect against adenomas and colorectal cancer, but not ASLs.

Keywords: Aspirin; Colorectal cancer; Colorectal polyps.

MeSH terms

  • Adenoma* / diagnosis
  • Adenoma* / epidemiology
  • Adenoma* / prevention & control
  • Aspirin
  • Colonic Polyps* / pathology
  • Colonoscopy
  • Colorectal Neoplasms* / diagnosis
  • Colorectal Neoplasms* / epidemiology
  • Colorectal Neoplasms* / prevention & control
  • Early Detection of Cancer / methods
  • Humans
  • Mass Screening
  • Occult Blood
  • Sigmoidoscopy

Substances

  • Aspirin