Implementation of genotype-guided dosing of warfarin with point-of-care genetic testing in three UK clinics: a matched cohort study

Jorgensen, Andrea L ORCID: 0000-0002-6977-9337, Prince, Clare, Fitzgerald, Gai, Hanson, Anita, Downing, Jennife ORCID: 0000-0001-7691-1167, Reynolds, Julia, Zhang, J Eunice ORCID: 0000-0003-1813-2207, Alfirevic, Ana ORCID: 0000-0002-2801-9817 and Pirmohamed, Munir ORCID: 0000-0002-7534-7266
(2019) Implementation of genotype-guided dosing of warfarin with point-of-care genetic testing in three UK clinics: a matched cohort study. BMC Medicine, 17 (1). 76-.

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Background:Warfarin is a widely used oral anticoagulant. Determining the correct dose required to maintain theinternational normalised ratio (INR) within a therapeutic range can be challenging. In a previous trial, we showedthat a dosing algorithm incorporating point-of-care genotyping information (‘POCT-GGD’approach) led to improvedanticoagulation control. To determine whether this approach could translate into clinical practice, we undertook animplementation project using a matched cohort design.Methods:At three clinics (implementation group;n= 119), initial doses were calculated using the POCT-GGDapproach; at another three matched clinics (control group;n= 93), patients were dosed according to the clinic’sroutine practice. We also utilised data on 640 patients obtained from routinely collected data at comparableclinics. Primary outcome was percentage time in target INR range. Patients and staff from the implementationgroup also provided questionnaire feedback on POCT-GGD.Results:Mean percentage time in INR target range was 55.25% in the control group and 62.74% in theimplementation group; therefore, 7.49% (95% CI 3.41–11.57%) higher in the implementation group (p=0.0004). Overall, patients and staff viewed POCT-GGD positively, suggesting minor adjustments to allow smoothimplementation into practice.Conclusions:In the first demonstration of the implementation of genotype-guided dosing, we show thatwarfarin dosing determined using an algorithm incorporating genetic and clinical factors can be implementedsmoothly into clinic, to ensure target INR range is reached sooner and maintained. The findings are like ourprevious randomised controlled trial, providing an alternative method for improving the risk-benefit ofwarfarin use in daily practice.

Item Type: Article
Uncontrolled Keywords: Anticoagulation, Warfarin, Genotype-guided dosing, Pharmacogenetics, Implementation study, Point-of-care
Depositing User: Symplectic Admin
Date Deposited: 09 Apr 2019 10:07
Last Modified: 19 Jan 2023 00:54
DOI: 10.1186/s12916-019-1308-7
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