The Association between Co-Administration of Omeprazole and Clopidogrel and Cardiovascular Outcomes

Abstract

Objective: To examine whether co-administration of clopidogrel and omeprazole affects the clinical outcomes of clopidogrel treatment. Design and Methods: A retrospective cross-sectional study of 4078 patients after a percutaneous coronary intervention and stent implantation. Seven hundred twenty-three clopidogrel-treated patients who fulfilled the inclusion criteria of the study were included: 318 treated only with clopidogrel; 405 treated with clopidogrel and omeprazole (study group). The interaction between the drugs was examined in relation to adverse clinical outcomes such as all-cause mortality, Major Adverse Cardiovascular Events (MACE) and cardiac hospitalizations during one year. Results: No significant difference was detected between the groups regarding the primary outcomes of the study. Regression models adjusted to basic characteristics and clinical variables showed a significant association between the study group and the primary outcomes through interactions with specific covariates: “all-cause mortality” through interaction with the covariate ethnicity (not-Jewish) (OR = 43.12, 95% CI 1.19-1567.8, P = 0.04), “MACE” through interaction with the covariates gender (female) and complicated angioplasty (OR= 9.36, 95% CI 2.04-42.94, P= 0.04); and “cardiac hospitalizations” through interaction with the covariates extent of artery stenosis and hypertension (OR= 2.65, 95% CI 1.043-6.76, P = 0.04). Conclusion: Addition of omeprazole to clopidogrel may be associated with increased incidence of negative clinical outcomes, including death and MACE. These findings underscore the need for conduction of prospective randomized controlled trials that will examine the association between addition of omeprazole to clopidogrel and the incidence of clinical outcomes.