To the Editor: The meta-analysis by Dr Mega and colleagues shows that among patients treated with clopidogrel for percutaneous coronary intervention, carriage of 1 reduced-function CYP2C19 allele is associated with an increased risk of major adverse cardiovascular events (hazard ratio [HR], 1.55; 95% confidence interval [CI], 1.11-2.17).1 Two methodological issues hamper the interpretation of the results.
Osnabrugge RLJ, Kappetein AP, Janssens ACJW. Carriage of Reduced-Function CYP2C19 Allele Among Patients Treated With Clopidogrel. JAMA. 2011;305(5):467-468. doi:10.1001/jama.2011.77