One-year clinical outcome in patients with acute coronary syndrome treated with concomitant use of clopidogrel and proton pump inhibitors: results from a regional cohort study

OBJECTIVES We sought to compare the 1-year risk of re-hospitalization for acute coronary syndrome (ACS) between patients taking clopidogrel with proton pump inhibitors (PPIs) vs. clopidogrel without PPIs. MATERIALS AND METHODS We conducted a retrospective cohort study among 3896 patients with ACS, at low risk for gastrointestinal bleeding, discharged from all hospitals of the Emilia-Romagna region of Italy during the period January-August 2008. Patients' consumption of clopidogrel and PPIs at hospital discharge and follow-up was based on pharmacy refill data. Of these 3896 patients, 90% (n = 3519) were prescribed PPIs at hospital discharge and/or at some time during follow-up. RESULTS At 1-year follow-up, hospitalization for ACS occurred in 15% of patients taking clopidogrel with PPIs vs. 3.4% of those taking clopidogrel without PPIs (P