Relationship between non-steroidal anti-inflammatory drug use and Helicobacter pylori infection in bleeding or uncomplicated peptic ulcers: A case-control study

BACKGROUND AND AIMS: Non-steroidal anti-inflammatory drug (NSAID) use has been closely associated with an increased risk of bleeding peptic ulcers, while the prevalence of Helicobacter pylori infection has been reported to be lower in bleeding ulcers than in non-bleeding ones. However, whether an interaction exists between NSAID use and H. pylori infection has not clearly been elucidated yet. The aims of this study were to determine the frequency of NSAID use and H. pylori infection, to predict risk factors in bleeding peptic ulcers and to determine whether NSAID use and H. pylori infection interact with each other. METHODS: Ninety-six patients with bleeding ulcer were included in the study. The control group consisted of 106 patients with non-bleeding ulcer. Data were analyzed by using the chi-squared test, Fisher's exact test and logistic regression analysis with or without interaction term (H. pylori by NSAID). RESULTS: Non-steroidal anti-inflammatory drug use was significantly more common in patients with bleeding ulcers than in controls (79.2 vs 38.7%, unadjusted odds ratio (OR): 6.02, 95% confidence interval (CI): 3.21-11.29). The frequency of the H. pylori infection was significantly lower in patients with bleeding ulcers than in controls (66.7 vs 89.6%, unadjusted OR: 0.23, 95% CI: 0.10-0.49). In the logistic regression analysis with the interaction term, male sex (adjusted OR: 3.70, 95% CI: 1.65-8.29), multiplicity of ulcers (adjusted OR: 4.10, 95% CI: 1.02-16.45) and NSAID use (adjusted OR: 33.87, 95% CI: 4.36-262.97) were independent risk factors for bleeding ulcers. There was a negative interaction between H. pylori and NSAID use (adjusted OR: 0.09, 95% CI: 0.01-0.83). CONCLUSIONS: The negative interaction between the two variables suggests that the presence of H. pylori is associated with a lower risk of bleeding in ulcer patients taking NSAIDs.