Low-dose aspirin use and cancer-specific mortality: a meta-analysis of cohort studies

Background Considering the increased risk of bleeding caused by aspirin, and the observed benefit in all-cause mortality may be due to an improvement in cardiovascular-related mortality. We carried out this meta-analysis to estimate the association of low-dose aspirin use and risk of cancer-specific mortality. Methods We searched the PubMed and China National Knowledge Infrastructure (CNKI) databases for all articles within a range of published years from 1980 to 2018. Results Finally, 13 published cohort studies with 65 768 patients were available for estimating overall risk of cancer-specific mortality associating with post-diagnosis low-dose aspirin use, and 4 cohort studies were available for pre-diagnosis low-dose aspirin use with 16 654 patients. Overall, statistical evidence of significantly decreased cancer-specific mortality was found to be associated with post-diagnosis low-dose aspirin use (OR = 0.84, 95% CI = 0.75-0.93), but not with pre-diagnosis low-dose aspirin use. In terms of subgroup analyses by cancer type, post-diagnosis low-dose aspirin use was significantly with decreased cancer-specific mortality for digestive tract cancer including colorectal cancer, esophageal cancer and gastric cancer. Conclusion Our meta-analysis indicated that post-diagnosis but not pre-diagnosis low-dose aspirin use may reduce cancer-specific mortality.