KUMJ | VOL. 15 | NO. 3 | ISSUE 59 | JULY-SEPT. 2017
Optimal Starting Dose of Warfarin for Treatment of Deep Vein Thrombosis in Nepalese Context, A Retrospective-Prospective Institutional Review
Shrestha BK, Karmacharya RM, Devbhandari M, Tuladhar SM
Abstract: Background
Deep vein thrombosis (DVT) requires an early establishment of effective
anticoagulation in order to reduce harms and cost of concomitant treatments.
Selection of the right warfarin dose at the start of treatment is important.
Objective
To know ideal starting dose of warfarin in adult with Deep Vein Thrombosis of our
population.
Method
This is a retrospective-prospective single institution based analytical study including
Deep Vein Thrombosis in adults from January 2015 to November 2017. On the first
half (January 1, 2015 to July 31, 2016) of the study period, the cases were given
3mg of warfarin as initial dose (Group 1); while in the second half (August 1, 2016
to November 31, 2017) cases were given 5mg as the initial dose (Group 2). Two
sequential International Normalisation Ratio (INR) within therapeutic range is
considered as target attained.
Result
There were total of 63 patients (M:F=1:1.03) of which 85.7% (n=54) cases were acute
deep vein thrombosis and 14.3% were chronic cases. Mean final dose of warfarin was
6.03 mg; where it was 6.50 mg in group 1 and 5.63 mg in group 2, p=0.11. Difference
between final dose and starting dose it was found to be 3.5 mg in Group 1 while that
was only 0.63 mg in Group 2 (p<0.01).
Conclusion
Lesser change in dose of warfarin from its initial starting dose (5 mg) was noticed
in group 2. Warfarin 6 mg as ideal starting dose can be recommended but larger,
multicentric and follow up studies are essential to substantiate the findings.
Keyword : Deep vein thrombosis, International normalisation ratio, Warfarin