A Matched Case-control Study of the Association between Low-dose Aspirin and Peptic Ulcers in Patients without a History of Peptic Ulcers

Background: Long-term administration of low-dose aspirin (LDA) is associated with greater risk of adverse events, including gastro duodenal ulcers. This study aimed to assess the risk factors and efficacy of medications to prevent the development of peptic ulcer disease in Japanese patients without prior history of peptic ulceration. Methods: We conducted a matched case-control study using esophagogastroduodenoscopy records collected from January through December 2010. We enrolled 219 consecutive outpatients receiving LDA (100 mg) and 219 ageand sex-matched controls who did not receive LDA and did not have a prior history of peptic ulcer. Clinical parameters, reason for endoscopy, and endoscopic findings were analyzed. Results: A significantly higher number of patients receiving LDA compared to those not receiving LDA were diagnosed endoscopically with peptic ulceration (20 [9.1%] vs. 7 [3.2%]; odds ratio [OR], 3.0; 95% confidence interval [CI], 1.26−7.35; p=0.016). Multiple logistic regression analysis identified male sex, abdominal symptoms, and non-steroidal anti-inflammatory drug (NSAID) and LDA use and PPI use as risk and protective factors, respectively, for peptic ulcer (OR, 4.7, 95% CI, 1.28−17.64, p=0.020; OR, 2.5, 95% CI, 1.01−6.12, p=0.047; OR, 6.8, 95% CI, 1.72−26.40, p=0.006; OR, 9.72; 95% CI, 2.64−35.72, p=0.006; and OR, 0.1, 95% CI, 0.04−0.57, p=0.006, respectively). Conclusion: LDA and NSAID use increases the risk of peptic ulcer even in patients without peptic ulcer history; proton pump inhibitors reduce the risk of developing gastric or duodenal ulcers. These results may help identify patients who require interventions for the prevention of NSAIDor LDA-induced peptic ulcers.