BACKGROUND: Warfarin dosing is difficult to establish because of considerable interindividual variation. Thus, warfarin pharmacogenetics have attracted particular interest in relation to appropriate control of anticoagulation. METHODS AND RESULTS: The 200 eligible subjects were chosen from participants in a hospital cohort. Performance of a pharmacogenetic algorithm recently developed by the International Warfarin Pharmacogenetics Consortium (IWPC) was tested and compared with a clinical algorithm (without genotype data) by calculating the percentage of patients for whom the predicted dose deviated by less than 7 mg/week (1 mg/day) from the actual dose. The pharmacogenetic algorithm accurately identified a significantly (P<0.05) larger proportion of patients to achieve the target international normalized ratio than did the clinical algorithm (68% vs 36% for a low-dose group; and 21% vs 0% for a high-dose group). Also, an increase in warfarin dosage was found to be appropriate for the current status of alcohol drinking (4 mg/week, as against non-drinking) and smoking (3.3 mg/week, as against non-smoking). CONCLUSIONS: The IWPC pharmacogenetic algorithm has clinical application, particularly in identifying Japanese patients who require a low dosage of warfarin and are at greater risk of excessive anticoagulation.
BACKGROUND:Warfarin dosing is difficult to establish because of considerable interindividual variation. Thus, warfarin pharmacogenetics have attracted particular interest in relation to appropriate control of anticoagulation. METHODS AND RESULTS: The 200 eligible subjects were chosen from participants in a hospital cohort. Performance of a pharmacogenetic algorithm recently developed by the International Warfarin Pharmacogenetics Consortium (IWPC) was tested and compared with a clinical algorithm (without genotype data) by calculating the percentage of patients for whom the predicted dose deviated by less than 7 mg/week (1 mg/day) from the actual dose. The pharmacogenetic algorithm accurately identified a significantly (P<0.05) larger proportion of patients to achieve the target international normalized ratio than did the clinical algorithm (68% vs 36% for a low-dose group; and 21% vs 0% for a high-dose group). Also, an increase in warfarin dosage was found to be appropriate for the current status of alcohol drinking (4 mg/week, as against non-drinking) and smoking (3.3 mg/week, as against non-smoking). CONCLUSIONS: The IWPC pharmacogenetic algorithm has clinical application, particularly in identifying Japanese patients who require a low dosage of warfarin and are at greater risk of excessive anticoagulation.
Authors: Stacie M Bratton; Carrie M Mosher; Farid Khallouki; Moshe Finel; Michael H Court; Jeffery H Moran; Anna Radominska-Pandya Journal: J Pharmacol Exp Ther Date: 2011-10-04 Impact factor: 4.030
Authors: Vincent A Fusaro; Prasad Patil; Chih-Lin Chi; Charles F Contant; Peter J Tonellato Journal: Circulation Date: 2012-12-21 Impact factor: 29.690
Authors: Nianjun Liu; Marguerite R Irvin; Degui Zhi; Amit Patki; T Mark Beasley; Deborah A Nickerson; Charles E Hill; Jinbo Chen; Stephen E Kimmel; Nita A Limdi Journal: Pharmacogenomics Date: 2017-07-07 Impact factor: 2.533