A regular, small dose of aspirin may help prevent cancer in general and colorectal cancers in particular, say findings published in JAMA Oncology.
The US Preventive Services Task Force recently recommended taking aspirin regularly to stave off CVD and colorectal cancer (CRC).
Dr. Andrew T. Chan, of the Massachusetts General Hospital in Boston, MA, and coauthors examined the effect of aspirin on cancer among 135,965 participants registered in two large cohort studies of health care professionals in the US.
The Nurses' Health Study ran from 1980-2010, and the Health Professionals Follow-up Study ran from 1986-2012.
Weekly aspirin reduces CRC risk by 19%
The team looked at 20,414 cases of cancers among 88,084 women and 7,571 cancers among 47,881 men over a period of 32 years.
Among people who took 0.5-1.5 standard aspirin tablets a week, the prevalence of cancers overall was 3% lower, with a 15% reduced risk of GI tract cancers and a 19% lower risk of developing colorectal cancer.
Results suggest that the effectiveness of aspirin in preventing CRC is dose-dependent.
Regular use of aspirin did not correlate with a lower risk of breast, prostate, lung or other major cancers. What effect, if any, aspirin might have on other types of cancer risk remains unclear.
Findings suggest that aspirin may impact additional mechanisms that contribute to the formation of cancer in the GI tract. This could explain the stronger association of aspirin with a lower risk of gastrointestinal cancers.
Aspirin may prevent CRC whether people undergo screening or not. However, findings indicate that substantially more cases were prevented among people who did not undergo screening.
In the general population, the researchers suggest that regular aspirin use by people aged 50 years or over could prevent CRC in people who do not adhere to screening.
The team estimates that 17% of cases of CRC were prevented among people who did not undergo lower endoscopy and 8.5% of CRC cases among those who underwent the screening.
The authors recommend balancing the benefits of aspirin for CVD and cancer with potential harms, such as GI tract bleeding.
"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 US population, in whom screening adherence remains suboptimal."
In a linked comment, Dr. Ernest T. Hawk, of the University of Texas MD Anderson Cancer Center in Houston, and coauthors highlight the study's findings regarding aspirin's potential impact for the general population, as well as the value that aspirin can add to the screening process.
Aspirin use, they say, could complement colorectal cancer screening and could be beneficial regardless of endoscopy status.
Medical News Today reported recently that causes of CRC differ according to age.