Cytochrome P450 2C9 gene polymorphism and warfarin maintenance dosage in pediatric patients: A systematic review and meta-analysis

Abstract

Aim: To assess the effect of Cytochrome P450 2C9 (CYP2C9) gene polymorphism on pediatric warfarin maintenance dosage requirement. Methods: A previously developed search strategy was conducted in PubMed, EMBASE, and the Cochrane Library. Eligible studies published prior to January 27, 2016, were identified and compared against strict inclusion/exclusion criteria. Required data were extracted, and researchers were consulted for additional data if needed. Review Manager version 5.2.3 software was used to analyze the relationship between CYP2C9 polymorphisms and warfarin maintenance doses in pediatric patients. Eight articles with a combined total of 507 pediatric patients were included in the meta-analysis. Results: Maintenance warfarin doses in patients with CYP2C9 *1/*2 genotype, CYP2C9 *1/*3 genotype, and CYP2C9 variant carriers which contain at least one variant allele (*2 or *3) were from 15% to 41% lower than doses in patients with the wild-type allele (CYP2C9 *1/*1): All differences were significant with P-values