Long-term use of aspirin was associated with a reduced risk for colorectal cancer, but an increased risk for gastrointestinal bleeding, highlighting the need to weigh the risks and benefits of prophylactic aspirin use, according to data presented at the Gastrointestinal Cancers Symposium.
Because data comparing the risks and benefits of long-term aspirin use are limited, Joseph Sung, MD, PhD, and Kevin K. F. Tsoi, PhD, of The Chinese University of Hong Kong, performed a population-based cohort study involving “a large cohort of 206,243 aspirin users compared with 482,966 non-users [who] were followed up to 14 years to document the incidence and mortality of colorectal cancer (CRC) and gastrointestinal bleeding (GIB) which might be related to the use of aspirin,” Sung told Healio Gastroenterology.
The aspirin users took daily aspirin for at least 6 months (mean dose, 80 mg per day; mean duration, 7.7 years), and the controls were matched by age and sex.
Overall, 5,776 (2.8%) of the aspirin users received a CRC diagnosis, and 2,097 (1.02%) died of CRC. In comparison, 16,483 (3.41%) controls received a CRC diagnosis, and 7,963 (1.65%) died of CRC.
Cox-proportional hazard regression analysis showed aspirin use was associated with “a modest but significant” reduced risk for CRC-related mortality (HR = 0.65; 95% CI = 0.62-0.69).
“Hence aspirin reduced CRC mortality by 35%,” Sung said.
However, 11,187 (5.42%) of the aspirin users had GI bleeding, and 841 (0.41%) died. In comparison, 15,186 (3.14%) controls had GI bleeding, and 1,682 (0.35%) died.
Cox-proportional hazard regression analysis showed aspirin use was also associated with “a modest but significant” increased risk for GI bleeding-related mortality (HR = 1.24; 95% CI = 1.14-1.35).
“Aspirin increased bleeding related mortality by 24%,” Sung said. "We conclude that aspirin as a prophylactic medication is a two-edged sword. Considerations of prophylactic use of aspirin should balance the benefit and the risk of this medication in specific populations.” – by Adam Leitenberger
Sung J, Tsoi KK. Abstract 527. Presented at: Gastrointestinal Cancers Symposium; Jan. 19-21, 2017; San Francisco.
Disclosures: The researchers report no relevant financial disclosures.
Editor's note: This article was updated on January 26 with additional information from the study author.