High Prevalence of Activated Protein C Resistance and Factor V Leiden Mutation in an Arab Population and Patients With Venous Thrombosis in Kuwait

Introduction: Activated protein C resistance (APC-R) because of clotting factor V Leiden mutation (FVL; Arg506Gln; G1691A) is a risk factor for the development of venous thromboembolic disorders (VTE). APC-R/FVL was reported to be very high in White patients with VTE (15% to 65%) and healthy populations (1% to 15%), and to be very low or absent in non-White patients. Studies on Arab patients and populations were very inconsistent. This study reports APC-R and FVL in Arabs living in Kuwait. Materials and Methods: Whole venous blood samples were collected from 400 patients with VTE and 200 healthy controls, all of whom were of Arab ethnicity living in Kuwait. The samples were used to separate plasma for an APC-R test, and DNA extraction for polymerase chain reaction and restricted fragment length polymorphism were performed. APC-R was on an automated hemostasis analyzer, and values less than 2.0 were reported as APC-R. Polymerase chain reaction and restricted fragment length polymorphism tests were performed using standard methods, and the results were reported as normal wild-type homozygous GG, FVL homozygous AA, or FVL heterozygous GA. Results: Sixty-three out of 400 patients (15.75%) and 4 out of 200 healthy controls (2%) had APC-R and at least one copy of FVL. Fifty-one patients and 4 controls were heterozygous whereas only 12 patients were homozygous. Conclusion: The prevalence of APC-R and FVL is quite high in Arabs living in Kuwait, being comparable with the prevalence reported in Whites, although being toward the lowest values reported there.