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Published on: February 28, 2012
Genetic influence on bleeding and over-anticoagulation risk in patients undergoing warfarin treatment after heart
Ling Zhou1, Yinglong Ding2, Yuan Gao1
1Department of Pharmacy, Soochow University, Suzhou, China.
Background: Warfarin acts in heart valve replacement patients to minimize thromboembolic complications. We investigated whether patients can be distinguished based on their genotypes to efficiently and safely administer warfarin therapy after heart valve replacements.Research design and methods: A retrospective analysis was conducted in patients with warfarin therapy who underwent elective heart valve replacements between January 2013 and September 2018. The patients were divided into normal, sensitive, and highly sensitive bins based on their CYP2C9 and VKORC1 genotypes. The primary endpoints were over-anticoagulation and overt bleeding.Results: 375 patients were enrolled, with 65 classified as normal, 281 as sensitive, and 29 as highly sensitive responders. Compared with normal responders, sensitive and highly sensitive responders spent more time on over-anticoagulation in the first 28 (P < 0.001) and 90 (P = 0.001) days; experienced more frequent bleeding events in the first 28 days (P = 0.029; OR, 2.18; 95% CI, 1.15-4.13); required lower warfarin doses to obtain stable INR (P < 0.001); had higher warfarin sensitivity indices (P < 0.001).Conclusion: Predicting evidence have been obtained with CYP2C9 and VKORC1 genotypes in identifying heart valve replacement patients with higher efficient sensitivity and with a higher risk of bleeding and over-anticoagulation.
Background: Warfarin acts in heart valve replacement patients to minimize thromboembolic complications. We investigated whether patients can be distinguished based on their genotypes to efficiently and safely administer warfarin therapy after heart valve replacements.Research design and methods: A retrospective analysis was conducted in patients with warfarin therapy who underwent elective heart valve replacements between January 2013 and September 2018. The patients were divided into normal, sensitive, and highly sensitive bins based on their CYP2C9 and VKORC1 genotypes. The primary endpoints were over-anticoagulation and overt bleeding.Results: 375 patients were enrolled, with 65 classified as normal, 281 as sensitive, and 29 as highly sensitive responders. Compared with normal responders, sensitive and highly sensitive responders spent more time on over-anticoagulation in the first 28 (P < 0.001) and 90 (P = 0.001) days; experienced more frequent bleeding events in the first 28 days (P = 0.029; OR, 2.18; 95% CI, 1.15-4.13); required lower warfarin doses to obtain stable INR (P < 0.001); had higher warfarin sensitivity indices (P < 0.001).Conclusion: Predicting evidence have been obtained with CYP2C9 and VKORC1 genotypes in identifying heart valve replacement patients with higher efficient sensitivity and with a higher risk of bleeding and over-anticoagulation.
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