BOSTON, March 3 (UPI) -- Long-term use of aspirin lowers overall cancer rates, most significantly because of its preventive effects against gastrointestinal cancers, according to a large study of people taking the drug.
Use of aspirin at least twice per week was linked to decreases in the risks for gastrointestinal cancers, which include cancers of the colon and rectum. It was not associated with lower risks for other cancers such as breast, prostate or lung, researchers at Massachusetts General Hospital reported.
Previous research has shown aspirin can reduce the risk for colon cancer, and a large study on the drug's ability to prevent cancer relapse is underway in Europe, with researchers planning to follow up to 11,000 participants for more than a decade.
"Aspirin may be a potential low-cost alternative to endoscopic CRC [colorectal cancer] screening in resource-limited settings or a complement in settings in which such programs are already implemented, including the general U.S. population, in whom screening adherence remains suboptimal," researchers write in the study, published in JAMA Oncology.
For the study, researchers reviewed the records of 135,965 healthcare professionals -- 88,084 women and 47,881 men -- who participated in the Nurses Health Study from 1980 to 2010 and the Health Professionals Follow-up Study from 1986 to 2012.
Among the participants, 20,414 cancers were diagnosed in the women and 7,571 were diagnosed among men. Regular use of aspirin twice or more per week was associated with a 3 percent lower risk for all cancer. For gastrointestinal cancer, though, the risk went down by 15 percent, and the risk for colorectal cancers -- both colon and rectal -- decreased by 19 percent.
"Perhaps the most important and unique contributions of this study are the team's assessment of aspirin's potential population-wide impact and its absolute benefits in the context of screening," researchers not involved in the study wrote in an editorial, also published in JAMA Oncology. "This finding is important because it suggests that aspirin use may complement CRC screening and may have an absolute benefit regardless of endoscopy status, a critical insight that few other studies have provided thus far."