Aspirin might reduce the incidence of pancreatic cancer: A meta-analysis of observational studies

Although there is evidence that non-steroidal anti-inflammatory drugs (NSAIDs) might be able to prevent pancreatic cancer, the findings from epidemiological studies have been inconsistent. In this paper, we conducted a meta-analysis of observational studies to examine this possibility. We searched PubMed and Embase for observational (cohort or case-control) studies examining the consumption of aspirin and other NSAIDs and the incidence of or mortality rates associated with pancreatic cancer. Twelve studies including approximately 258,000 participants in total were analysed. The administration of aspirin significantly reduced the incidence of pancreatic cancer (8 studies; odds ratio (OR) = 0.77; 95% confidence interval (CI) = 0.62 to 0.96; I(2) = 74.2%) but not the mortality associated with it (2 studies; OR = 0.94; 95% CI = 0.73 to 1.22). Specifically, frequent aspirin use was associated with reduced pancreatic cancer incidence (OR = 0.57; 95% CI = 0.39 to 0.83 for high frequency; OR = 0.57; 95% CI = 0.38 to 0.84 for medium frequency). The summary ORs regarding the incidence of pancreatic cancer and either non-aspirin NSAIDs use (OR = 1.08; 95% CI = 0.90 to 1.31) or overall NSAIDs use (OR = 0.97; 95% CI = 0.86 to 1.10) were not significant. In conclusion, aspirin use might reduce the incidence of pancreatic cancer; however, this finding should be interpreted with caution because of study heterogeneity.