Low-dose aspirin reduces risk for many cancers

Issue: May 10, 2017

Adults who take low-dose aspirin over an extended period of time demonstrated lower mortality from many cancers, including breast cancer, prostate cancer and lung cancer, according to data presented at the American Association for Cancer Research Annual Meeting.

“Accumulating evidence suggests that aspirin not only reduces the risk for developing cancer, but may also play a strong role in reducing death of cancer,” Yin Cao, MPH, ScD, instructor in medicine at the clinical and translational epidemiology unit of Massachusetts General Hospital and Harvard Medical School, said in a press release.

Yin Cao

Aspirin’s role in the prevention of cardiovascular disease and colorectal cancer prompted the U.S. Preventive Services Task Force to recommend low-dose aspirin for adults aged 50 to 69 years.

Cao and colleagues explored the role of aspirin in overall mortality, as well as in certain cancers. Using data from the Nurses’ Health Study from 1980 to 2012 and the Health Professionals Follow-Up Study from 1986 to 2012, researchers assessed aspirin use at baseline and every 2 years thereafter in 86,206 women and 43,977 men.

At 32-years’ follow-up, 8,271 of 22,094 women and 4,591 of 14,749 men died of cancer.

Researchers observed benefits in dosages ranging from 0.5 aspirin tablets per week to seven tablets per week for at least 6 years.

Compared with nonregular aspirin use, overall mortality risk was 7% lower for women (RR = 0.93; 95% CI, 0.9-0.95) and 11% lower for men (RR = 0.89; 95% CI, 0.86-0.93) who used aspirin regularly. Cancer mortality risk also was 7% lower for women who regularly used aspirin (RR = 0.93; 95% CI, 0.89-0.97) and 15% lower for men (RR = 0.85; 95% CI, 0.8-0.9).

Aspirin use had a strong association with reduced mortality risk from colorectal cancer in both women (RR = 0.6; 95% CI, 0.59-0.81) and men (RR = 0.7; 95% CI, 0.57-0.85). Aspirin use conferred an 11% reduced risk for breast cancer mortality in women (RR = 0.89, 95% CI, 0.79-0.99), 23% reduced risk for prostate cancer mortality in men (RR = 0.77; 95% CI, 0.65-0.90), and a 14% reduced risk for lung cancer mortality in men (RR = 0.86; 95% CI, 0.74-0.99).

“These findings suggest that aspirin’s established benefits in cardiovascular disease and colorectal cancer reduction may extend to other common causes of death, including several major cancers,” Cao said.

Researchers acknowledged that the observational nature of this study made it less definitive than a randomized clinical trial.

“We need to conduct additional work to balance these benefits against the harms of use, such as gastrointestinal tract bleeding and hemorrhagic stroke,” Cao said. – by Chuck Gormley

Reference:

Cao, Y, et al. Abstract 3012. Presented at: AACR Annual Meeting; April 1-5, 2017; Washington, D.C.

Disclosure: The NIH funded this study. The researchers report no relevant financial disclosures.