Multiple observational studies and large, randomized controlled trials indicate that non-steroidal anti-inflammatory drugs (NSAIDs) strongly reduce risk for colorectal neoplasms. However, the strengths of these findings suggest that NSAIDs may so mask various risk factor-colorectal neoplasm associations, that they may be undetectable among NSAID users. We investigated whether various risk factor-colorectal neoplasm associations differed by non-aspirin NSAID use using pooled data from three colonoscopy-based case-control studies of incident, sporadic colorectal adenoma conducted in Minnesota, North Carolina, and South Carolina between 1991 and 2002. Participants (n = 789 cases, 2,035 polyp-free controls) provided risk factor data prior to colonoscopy. The multivariable-adjusted odds ratios (OR) (95% confidence intervals [CI]) for those in the highest relative to the lowest quartiles of exposure, by regular non-aspirin NSAID non-use/use, respectively, were 1.57 (CI 0.96, 2.55) vs. 1.14 (0.37, 3.49) for total fat, 1.37 (CI 0.86, 2.18) vs. 0.70 (CI 0.23, 2.25) for saturated fat, 0.93 (CI 0.68, 1.28) vs. 1.30 (CI 0.61, 2.75) for calcium, 0.89 (CI 0.64, 1.23) vs. 1.38 (CI 0.65, 2.94) for total fruits and vegetables, 1.04 (CI 0.73, 1.49) vs. 0.70 (CI 0.31, 1.56) for total red and processed meats, and 0.85 (CI 0.65, 1.11) vs. 0.94 (CI 0.52,1.71) for physical activity. For current versus never smokers, the ORs (CIs) among regular non-NSAID users/non-users were 2.91 (CI 2.22, 3.82) vs. 1.75 (CI 0.90, 3.41), and for those who were obese versus those who were normal weight, they were 1.67 (CI 1.28, 2.17) vs. 1.19 (CI 0.69, 2.04). The associations of age, height, intakes of alcohol, dietary fiber, and total folate, hormone replacement therapy, and oxidative balance score with adenoma did not substantially differ according to NSAID use.
These findings suggest that regular non-aspirin NSAID use may mask, beyond simple confounding, associations of major risk factors with colorectal adenoma, and support routinely assessing such associations stratified by regular non-aspirin NSAID use.
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Summary, Public Health implications, Possible Future Directions 46
About this Master's Thesis
|Committee Chair / Thesis Advisor|
|Differences in Risk Factor-Colorectal Adenoma Associations According to Nonsteroidal Anti-inflammatory Drug Use ()||2018-08-28||