Incidence and risk factors of gastrointestinal bleeding in patients on low-dose aspirin therapy after percutaneous coronary intervention in Japan

Background. Low-dose aspirin (LDA) is the most commonly prescribed antiplatelet agent for prevention of cardiovascular events following percutaneous coronary intervention (PCI). Long-term treatment with LDA has serious adverse effects, including gastrointestinal (GI) hemorrhage. Most studies have focused only on upper GI bleeding and few studies have evaluated the effect of LDA on total GI bleeding. Aims. The aims of this study were to investigate the incidence and risk factors of total GI bleeding within 30 days after PCI in Japanese patients taking LDA. Methods. A retrospective chart review was conducted for 364 patients undergoing LDA therapy following PCI at Osaka City University Hospital. A retrospective case-control study evaluated risk factors using the chi-squared test and logistic regression. Results. The incidence of total GI bleeding after PCI within 30 days was 4.3%. The source of the GI bleeding was located throughout the GI tract. Risk factors identified by univariate analysis were age ≥75 years, history of peptic ulcer disease, chronic renal failure, proton pump inhibitor use, and histamine H2 receptor antagonist use. By multivariate logistic regression only age ≥75 years (odds ratio = 5.26; 95% confidence interval: 1.13-24.51; p = 0.035) was found to be an independent risk factor of GI bleeding. Conclusions. The incidence of GI bleeding in patients undergoing LDA therapy following PCI is high. The bleeding episodes were located in the upper, middle, and lower GI tract. Age of ≥75 years was an independent risk factor for GI bleeding after PCI in patients on LDA therapy.