Effects of Clopidogrel and Proton Pump Inhibitors on Cardiovascular Events in Patients with Type 2 Diabetes Mellitus after Bare Metal Stent Implantation: A Nationwide Cohort Study.

Background: To investigate whether there is an increased risk of cardiovascular (CV) events in patients with diabetes associated with adding proton pump inhibitors (PPIs) to clopidogrel (CLO) therapy after bare-metal stent (BMS) deployment.

Methods: We used the National Health Insurance Research Database to conduct this retrospective cohort study. We enrolled 6,757 patients with diabetes who underwent BMS deployment and received CLO with/without PPIs for 90 days (6,243 in the CLO subgroup and 514 in the CLO plus PPI subgroup). The endpoints were acute coronary syndrome and re-admission for revascularization (PCI or coronary artery bypass graft surgery) after 3, 6, and 12 months.

Results: The patients who received CLO with PPIs had no significant increase in adverse CV events compared to those without PPIs within 1 year after BMS deployment [3-month hazard ratio (HR) = 0.87, 95% confidence interval (CI), 0.65-1.15; 6 months, HR = 0.95, 95% CI, 0.78-1.15; 1 year, HR = 0.60, 95% CI, 0.81-1.12].

Conclusions: In patients with diabetes undergoing BMS deployment, there was no evidence of an increased risk of CV events among concomitant users of CLO and PPIs. Our results indicate that the use of PPIs may not modify the protective effect of CLO after BMS implantation.