Aspirin but not statins is inversely related to gastric cancer with a duration-risk effect: results from the Stomach Cancer Pooling (StoP) Project Consortium

Abstract Background Aspirin and statins have been suggested to have potential chemopreventive effects against gastric cancer (GC), although results of previous studies have been inconsistent. Therefore, we aimed to investigate the association between the use of aspirin and statins, alone or in combination, and GC. Methods We conducted a pooled analysis of seven case-control studies within the Stomach cancer Pooling (StoP) Project, including 3220 cases and 9752 controls. Two-stage modelling analyses were used to estimate the associations between aspirin use, statin use, and combined use of the two drugs, and GC after adjusting for potential confounders. Results The pooled odds ratio (OR) of GC for aspirin users versus non-users was 0.72 (95% confidence interval [CI] = 0.54–0.95). The protective effect of aspirin appeared stronger in individuals without a GC family history (OR: 0.60, 95% CI: 0.37–0.95). The OR of GC decreased with increasing duration of aspirin use, with an OR of 0.41 (95% CI: 0.18–0.95) for durations ≥ 15 years. An inverse, non-statistically significant association with risk of GC was observed for use of statins alone (OR: 0.79, 95% CI: 0.52–1.18). Conclusions Our findings suggest that aspirin use, particularly long-term use, is associated with a reduced risk of GC, while a similar association was not observed with statins, possibly due to low frequency of use.