Age- and weight-adjusted warfarin initiation nomogram for ischaemic stroke patients
Version of Record online: 4 JUN 2012
© 2012 The Author(s) European Journal of Neurology © 2012 EFNS
European Journal of Neurology
Volume 19, Issue 12, pages 1547–1553, December 2012
How to Cite
Yoo, S.-H., Kwon, S. U., Jo, M.-W., Kang, D.-W. and Kim, J. S. (2012), Age- and weight-adjusted warfarin initiation nomogram for ischaemic stroke patients. European Journal of Neurology, 19: 1547–1553. doi: 10.1111/j.1468-1331.2012.03772.x
- Issue online: 17 NOV 2012
- Version of Record online: 4 JUN 2012
- Manuscript Accepted: 24 APR 2012
- Manuscript Received: 31 OCT 2011
- the Korea Health 21 Research and Development Project. Grant Number: A102065
- Korea Healthcare technology R&D Project. Grant Number: A070001
- ischaemic stroke;
- warfarin initiation nomogram
Specific guidelines for initial dosing of warfarin in ischaemic stroke patients have not been developed. Therefore, we have developed an age- and weight-adjusted warfarin initiation nomogram (AW-WIN) for ischaemic stroke patients and then evaluated the efficacy and safety of AW-WIN compared with physician-determined warfarin dosing (PDWD).
The age- and weight-adjusted warfarin initiation nomogram was administered to 104 acute ischaemic stroke patients between January 2008 and February 2009. A historical control group (PDWD) of 96 patients was selected from comparable patients who were discharged with warfarin during the previous year. Time-to-therapeutic international normalized ratios (INRs) and the incidence of excessive anticoagulation were compared in the AW-WIN and PDWD groups.
The general characteristics, risk factors, and stroke mechanism of the AW-WIN and PDWD groups did not differ significantly. The mean time to INR ≥ 2.0 was significantly shorter in the AW-WIN than in the PDWD group (4.9 ± 0.7 vs. 6.2 ± 0.8 days, P = 0.0008). After adjustment for potential confounding variables, the AW-WIN group reached target INR faster than the PDWD group (hazard ratio, 1.76; 95% confidence interval, 1.26–2.45; P = 0.001). The time-to-therapeutic INR ≥1.7 was shorter (P = 0.0002), the proportion of patients with therapeutic INR (2–3) at 5 days was higher (P = 0.002), and the rate of excessive anticoagulation of ≥3.5 INR during hospitalization was lower (P = 0.024) in the AW-WIN than in the PDWD group.
AW-WIN reduces the time to target INR and the risk of excessive anticoagulation. AW-WIN may be an efficient and safe method of anticoagulation during the acute phase of ischaemic stroke.