Purpose: Nonsteroidal anti-inflammatory drugs (NSAIDs) play protective roles in gastric carcinogenesis. However, the interaction between NSAIDs and Helicobacter pylori (H pylori) infection and the number needed to treat to prevent gastric cancer remains unclear.
Patients and methods: We conducted a nationwide retrospective cohort study based on data from the Taiwan National Health Insurance Database. Hospitalized patients with a primary diagnosis of peptic ulcer disease were selected. Overall, 52,161 patients were divided into non-NSAID user and regular NSAID user cohorts. Standardized incidence ratios (SIRs), cumulative incidences, and hazard ratios (HRs) were calculated.
Results: Patients with peptic ulcers who never used NSAIDs had higher risk of gastric cancer compared with the general population (SIR, 2.11; 95% CI, 2.07 to 2.15), but regular NSAID use conferred lower risk (SIR, 0.79; 95% CI, 0.77 to 0.81). The protective role of NSAID use was observed in patients with gastric ulcer, but not in patients with non-H pylori-associated duodenal ulcer. On multivariate analysis, regular NSAID use was an independent protective factor for gastric cancer development (HR, 0.79 for each incremental year; P < .001), especially in H pylori-associated patients (HR, 0.52 for each incremental year; P < .001). Among patients with H pylori-infected gastric ulcers, the NNT to prevent a gastric cancer was 50.
Conclusion: Regular NSAID use may be a feasible way to prevent gastric cancer, at least in patients with gastric ulcers, and especially in H pylori-infected subjects.