Proton Pump Inhibitor for Gastrointestinal Bleeding in Patients with Myocardial Infarction on Dual-Antiplatelet Therapy: A Nationwide Cohort Study.

Background: Guidelines provide various recommendations for the use of proton pump inhibitors (PPI) to prevent upper gastrointestinal (UGI) bleeding in acute myocardial infarction (MI) treatment with dual antiplatelet therapy (DAPT). We evaluated the effects of PPIs in reducing the risk of severe UGI bleeding in patients with MI receiving DAPT.

Methods: This retrospective cohort study included patients admitted for acute MI between 2014 and 2018, based on a nationwide health claims database in Korea. Primary outcome was admission for severe UGI bleeding requiring transfusion within 1 year of MI diagnosis. A multivariable Cox regression model was used to calculate the association between PPI use and severe UGI bleeding risk.

Results: Of 100,556 patients with MI on DAPT (mean age, 63.7 years; 75.4% men), 37% were prescribed PPIs. Based on risk assessment for UGI bleeding, among 6,392 (6.4%) high-risk and 94,164 (93.6%) low-risk patients, 50.5% and 35.8% received PPIs, respectively. Overall, 0.5% of the patients experienced severe UGI bleeding within 1 year after MI. The use of PPI was associated with a reduced risk of severe UGI bleeding (hazard ratio [HR], 0.57; 95% confidence interval [CI], 0.47-0.70; P < 0.001). The benefits of PPIs were consistent in high-risk (HR, 0.71; 95% CI, 0.45-1.13; P = 0.147) and low-risk (HR, 0.54; 95% CI, 0.43-0.68; P < 0.001) patients (P for interaction = 0.481).

Conclusions: Among Korean patients with MI receiving DAPT, PPIs were underutilized, even among those at high risk of severe UGI bleeding. Nonetheless, PPI use reduced severe UGI bleeding in low- and high-risk groups.