Impact of VKORC1, CYP4F2 and NQO1 gene variants on warfarin dose requirement in Han Chinese patients with catheter ablation for atrial fibrillation.

BACKGROUND: The anticoagulation of atrial fibrillation catheter ablation during the perioperative stage does matter and should be treated with discretion. We aimed to assess impact of three important genes participating in vitamin K cycle (i.e. VKORC1 rs9923231, CYP4F2 rs2108622 and NQO1 rs1800566) on the daily stable warfarin dose requirement in Sichuan Han Chinese patients with catheter ablation of atrial fibrillation.

METHODS: A total of 222 atrial fibrillation patients taking stable warfarin therapy after catheter ablation operation were enrolled in this study. The study population included had high (≥2) risk according to the CHA2DS2-VASc risk score. Genotypes of VKORC1 rs9923231, CYP4F2 rs2108622 and NQO1 rs1800566 were analyzed by using the polymerase chain reaction restriction fragment length polymorphism method (PCR-RFLP). Multiple linear regression analysis was applied to depict the impact of VKORC1 rs9923231, CYP4F2 rs2108622 and NQO1 rs1800566 on the daily stable warfarin dose requirement.

RESULTS: Carriers of VKORC1 rs9923231 AG/GG genotypes required significantly higher warfarin dose (3.03 ± 0.28 mg/day, 7.19 mg/day, respectively) than AA carriers (2.52 ± 0.07 mg/day; P < 0.001). Carriers of CYP4F2 rs2108622 CT/TT genotypes required significantly higher warfarin dose (3.38 ± 0.22 mg/day, 2.79 ± 0.19 mg/day, respectively) than CC carriers (2.41 ± 0.08 mg/day; P < 0.001). However, the warfarin dose for carriers of NQO1 rs1800566 CT/TT genotypes (2.46 ± 0.24 mg/day, 3.01 ± 0.27 mg/day, respectively) was not significantly higher than that for the CC carriers (2.33 ± 0.1 mg/day). The multiple linear regression model including genotypes and demographic characteristics, could explain 20.1% of individual variations in the daily stable warfarin dose in Sichuan Han Chinese. VKORC1 rs9923231 contributed most (15%) to the individual variations in daily stable warfarin dose, while CYP4F2 rs2108622 contributed least (3%).

CONCLUSION: NQO1 rs1800566 is not a significant genetic factor of warfarin dose for Han Chinese, whereas VKORC1 rs9923231 and CYP4F2 rs2108622 are significant genetic factors, which could explain 15% and approximately 3% of individual variations in the daily stable warfarin dose respectively.