Long-term aspirin use is linked to lower risk for developing gastrointestinal tract cancers, according to US researchers.
Their study found regular low doses of aspirin for at least six years was associated with a modestly reduced overall cancer risk, primarily due to a lower risk for gastrointestinal tract cancer, especially colorectal cancers.
“Regular aspirin use may prevent a substantial proportion of colorectal cancers”
Researchers from Boston’s Massachusetts General Hospital looked at the association of aspirin with cancer among 135,965 women and men enrolled in two large US studies of health care professionals.
The authors documented 20,414 cancers among 88,084 women and 7,571 cancers among 47,881 men during a 32-year follow-up.
Regular use of aspirin twice or more per week was linked with a 3% lower risk for overall cancers, which was mostly due to a 15% lower risk for gastrointestinal tract cancers and a 19% lower risk for cancers of the colon and rectum.
However, regular use of aspirin was not associated with a lower risk for other major cancers, such as breast, prostate or lung, the authors report in the journal JAMA Oncology.
“This interesting study provides further evidence of the effectiveness of aspirin”
The researchers suggest that, for the gastrointestinal tract, aspirin may influence additional mechanisms important for the formation of cancer – explaining the stronger association of aspirin for a lower risk of gastrointestinal cancers.
The authors suggested regular aspirin use could prevent 17% of colorectal cancers among those who did not undergo lower endoscopy and 8.5% among those who underwent lower endoscopy.
They suggested that aspirin could be a “potential low-cost alternative” to colorectal screening.
“Long-term aspirin use was associated with a modest but significantly reduced risk for overall cancer, especially gastrointestinal tract tumors,” they said.
“Regular aspirin use may prevent a substantial proportion of colorectal cancers and complement the benefits of screening,” they added.
In response to the study, Bowel Cancer UK chief executive Deborah Alsina said: “This interesting study provides further evidence of the effectiveness of aspirin in helping to reduce the risk of colorectal (bowel) cancer, particularly if taken regularly by people over the age of 50.
“We also know from other studies that it can be particularly effective in people at higher risk of the disease, such as those with Lynch Syndrome,” she said. “However, in the UK we are still waiting for clarity over dosage and duration that aspirin should be taken for.”