Activated Protein C Resistance and Factor V Leiden Mutation in Patients with Arterial Ischemic Stroke

ABSTRACT

BACKGROUND: In the western hemisphere, resistance to activated protein C (APCR) is the most common risk factor for venous thromboembolic disease. A one-point mutation in the coagulation factor V that renders it APCR is found in more than 90% of patients with APC-resistant venous thrombosis. In Hispanic and Caucasian patients with arterial ischemic stroke, the prevalence of APC-R is approximately 10%. To determine the prevalence of APC resistance and its causative factor V mutation (Arg 506 Gln) in Koreans, we screened a group of Korean ischemic stroke patients. METHODS: We evaluated 60 Korean patients with arterial ischemic stroke diagnosed by either magnetic resonance neu-roimaging, conventional angiogram, or both, after 2 weeks of symptom onset. The mean age of the subjects was 59.2 years (13-82 years). APC resistance was expressed as a ratio of the activated partial thromboplastin time (aPTT) with and without adding APC to the subject's plasma. The presence of the factor V Leiden (Arg 506 Gln) mutation was determined by a direct polymerase chain reaction-based assay on peripheral blood leukocytes. RESULTS: Only one patient (n=1/60, 1.6%) had APC resistance and none were found to have the factor V Leiden (Arg 506 Gln) mutation. CONCLUSIONS: APCR and the factor V Leiden mutation do not seem to be a significant genetic risk factor for arterial ischemic stroke in Koreans.