Significant increase in clopidogrel use across U.S. children's hospitals.

The primary aim of this study was to describe the use of the antiplatelet agent clopidogrel in pediatric tertiary care hospitals and to evaluate how it has changed over time. This retrospective cohort study of pediatric inpatients from 2000 to 2009 used the Pediatric Health Information System database (PHIS) which contains data from 42 U.S. tertiary care children's hospitals. Pharmacy billing codes were used to identify hospital admissions during which clopidogrel was administered. Patient demographics and concurrent use of other anticoagulant and antiplatelet drugs were collected. The International Classification of Diseases, ninth edition (ICD-9) codes were used to categorize admissions by potential indications for antiplatelet drugs and to identify bleeding and thrombotic events. From 2001 to 2009, clopidogrel use increased 15-fold, from 6 to 89.5 per 100,000 admissions. Patients with cardiac disease accounted for the largest proportion (75%), followed by stroke (9.4%) and Kawasaki disease (6.1%). Among those with cardiac disease, hypoplastic left heart syndrome (38%) and pulmonary artery anomalies (37%) were the most common. Aspirin was used concurrently during 52% of the admissions, enoxaparin during 9%, and warfarin during 5%. The use of clopidogrel is increasing rapidly among children with cardiovascular diseases. This population has a high risk of bleeding, thrombosis, and mortality. It therefore is imperative that future studies continue to evaluate the safety and efficacy of clopidogrel for these children.