WASHINGTON—The regular use of aspirin significantly reduces overall risk of cancer and particularly lowers the risk of colorectal cancer and other gastrointestinal tract tumors, according to an analysis of data from two major, long-term epidemiologic studies. The findings were published online this week in JAMA Oncology.
According to researchers, aspirin should compliment—not replace—preventive cancer screening methods like colonoscopies.
"We now can recommend that many individuals consider taking aspirin to reduce their risk of colorectal cancer - particularly those with other reasons for regular use, such as heart disease prevention - but we are not at a point where we can make a general recommendation for overall cancer prevention," said Dr. Andrew Chan, senior report author and chief of the Clinical and Translational Epidemiology Unit at the Massachusetts General Hospital (MGH) Division of Gastroenterology in a press release.
"Our findings imply that aspirin use would be expected to prevent a significant number of colorectal cancers above and beyond those that would be prevented by screening and may have even greater benefit in settings in which the resources to devote to cancer screening are lacking."
Even though previous research has found that regular use of aspirin can prevent colorectal cancer, the effect of regular aspirin use on overall cancer risk has not been studied extensively.
For this investigation, researchers analyzed 32 years of data for nearly 136,000 participants in the Nurses' Health Study and the Health Professionals Follow-up Study. For purposes of this investigation, they defined regular use of aspirin as taking either a low-dose or standard aspirin tablet at least twice a week.
Researchers found that participants reporting regular aspirin use had a 3 percent absolute lower risk of developing any type of cancer compared to participants who did not report regular aspirin use. Moreover, the risk of colorectal cancer was reduced by 19 percent and the risk of gastrointestinal cancer was reduced by 15 percent in those who regularly used aspirin.
The protective benefit from aspirin appeared after five years of continuous usage of a dose between .5 and 1.5 standard aspirin tablets per week or one low-dose tablet per day.
Researchers concluded that regular aspirin use could prevent nearly 30,000 gastrointestinal tract tumors in the U.S. every year. Regular aspirin use could also prevent an additional 7,500 colorectal tumors among adults over 50 who undergo endoscopic screening and 9,800 tumors among those who are not screened.
"At this point, it would be very reasonable for individuals to discuss with their physicians the advisability of taking aspirin to prevent gastrointestinal cancer, particularly if they have risk factors such as a family history," said Dr. Chan. "But this should be done with the caveat that patients be well informed about the potential side effects of regular aspirin treatment and continue their regular screening tests. Furthermore, aspirin should not be viewed as a substitute for colonoscopy or other cancer screening tests."
