Purpose: The US Food and Drug Administration (FDA) issued three safety announcements between January 2009 and October 2010 warning against concomitant use of clopidogrel and proton pump inhibitors (PPIs) due to a potential drug-drug interaction that may attenuate clopidogrel's antiplatelet activity. This primary objective of this study was to examine trends in concomitant clopidogrel/PPI use among acute coronary syndrome (ACS) inpatients in the US between 2000 and 2016, in relation to the FDA safety communications.
Methods: Adult inpatients with a primary diagnosis of ACS were identified from the Cerner Health Facts® database. The standardized (age, sex, race, and census region) prevalence of clopidogrel use with PPIs was calculated yearly and quarterly. Findings were stratified by PPIs' potential to inhibit clopidogrel's activity and by age.
Results: A total of 204,533 inpatients were identified. In 2008, the prevalence of concomitant clopidogrel and PPI treatment was 34.9%, decreasing to 24.4 and 16.4% in 2009 and 2010, respectively, with the decline being similar across age groups. Treatment with inhibiting PPIs (omeprazole and esomeprazole) and clopidogrel has continued to decrease since 2010, with a prevalence of 0.8% in 2016. A similar reduction was not observed with clopidogrel and non-inhibiting PPIs (pantoprazole, lansoprazole, rabeprazole, and dexlansoprazole). During the FDA warning period, the combined treatment with clopidogrel and H2 receptor antagonists, an alternative to PPIs suggested by the FDA, temporarily increased from 7.8% in 2008 to 12.8 and 14.5% in 2009 and 2010, respectively.
Conclusions: Findings suggest that clinical practice recommendations made by the FDA were followed. Further research is needed to determine how changes in drug labels and the availability of new drugs may have influenced the observed trends.
Keywords: Acute coronary syndrome; Clopidogrel; Drug utilization; Medical records; Proton pump inhibitors.