Adenomatous polyps are known precursor lesions for
colorectal cancer and some hyperplastic
polyps also have malignant potential. The use of
aspirin and nonsteroidal anti-inflammatory drugs (
NSAID) is associated with a reduced risk of
adenomatous polyps; however, less evidence exists with regard to
NSAID use and hyperplastic
polyp risk. We conducted a colonoscopy-based case-control study including 2,028
polyp cases (1,529 adenomatous and 499 hyperplastic) and 3,431
polyp-free controls. Multivariate logistic regression models were constructed to derived adjusted
ORs and 95% CIs as the measure of the association between
NSAID use and
polyp risk. Use of baby
aspirin, regular
aspirin, and nonaspirin
NSAIDs, were associated with a reduced risk of
adenomatous polyps (OR = 0.79, 95% CI: 0.66-0.93, OR = 0.73, 95% CI: 0.58-0.90, and OR = 0.67, 95% CI: 0.53-0.86, respectively). Baby
aspirin was also associated with a reduced risk of hyperplastic
polyps (OR = 0.74, 0.56-0.97). Although a dose response was seen with
adenoma risk and regular use of any
NSAIDs (less than 7 doses per week, 7 doses per week, and greater than 7 doses per week), a dose response was not seen with hyperplastic
polyps. We found no evidence of interaction between
NSAID dose and duration and
polyp risk. The use of any
NSAID regardless of type was associated with a reduced risk of
adenomatous polyps; however, regular
aspirin and
COX-2 inhibitors use was not associated with hyperplastic
polyp risk.