Aspirin Use Does Not Cut Colorectal Cancer Risk
Large, six-year follow-up study shows no effect on invasive colon or rectal cancer
TUESDAY, Sept. 19 (HealthDay News) -- Aspirin use may have little effect on reducing the risk of colon cancer, according to findings from a prospective study of more than 91,000 women with a six-year follow-up. The results are published in the Sept. 15 issue of the American Journal of Epidemiology.
While the protective effect of aspirin use on cardiovascular disease has been well established, previous studies have shown conflicting results regarding colorectal cancer risk, according to Matthew Allison, M.D., M.P.H., from the University of California San Diego, and colleagues. The group used data from the Women's Health Initiative to re-examine aspirin use and colorectal cancer risk.
The investigators identified 631 cases of invasive cancer of the colon or rectum, and found no relationship with aspirin use and cancer risk. They note that their sample size was more than adequate to detect the 20 percent to 30 percent reduction in colorectal cancer risk reported in previous studies. A longer follow-up may be needed to see any effects, since colorectal cancer may develop over 20 years.
"Although we did not observe an effect of aspirin on the incidence of colorectal cancer, many other associations were present that have been demonstrated in previous studies," the authors write.