Optimal timing of resumption of warfarin after intracranial hemorrhage

Stroke. 2010 Dec;41(12):2860-6. doi: 10.1161/STROKEAHA.110.593087. Epub 2010 Oct 28.


Background and purpose: The optimum timing of resumption of anticoagulation after warfarin-related intracranial hemorrhage in patients with indication for continued anticoagulation is uncertain. We performed a large retrospective cohort study to obtain more precise risk estimates.

Methods: We reviewed charts of 2869 consecutive patients with objectively verified intracranial hemorrhage over 6 years at 3 tertiary centers. We calculated the daily risk of intracranial hemorrhage or ischemic stroke with and without resumption of warfarin; we focused on patients who survived the first week and had cardiac indication for anticoagulation or previous stroke. Using a Cox model, we estimated rates for these 2 adverse events in relation to different time points of resumed anticoagulation. The combined risk of either a new intracranial hemorrhage or an ischemic stroke was calculated for a range of warfarin resumption times.

Results: We identified warfarin-associated intracranial hemorrhage in 234 patients (8.2%), of whom 177 patients (76%) survived the first week and had follow-up information available; the median follow-up time was 69 weeks (interquartile range [IQR] 19-144). Fifty-nine patients resumed warfarin after a median of 5.6 weeks (IQR 2.6-17). The hazard ratio for recurrent intracranial hemorrhage with resumption of warfarin was 5.6 (95% CI, 1.8-17.2), and for ischemic stroke it was 0.11 (95% CI, 0.014-0.89). The combined risk of recurrent intracranial hemorrhage or ischemic stroke reached a nadir if warfarin was resumed after approximately 10 to 30 weeks.

Conclusions: The optimal timing for resumption of warfarin therapy appears to be between 10 and 30 weeks after warfarin-related intracranial hemorrhage.

Publication types

  • Multicenter Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Anticoagulants / administration & dosage
  • Anticoagulants / adverse effects*
  • Anticoagulants / therapeutic use*
  • Brain Ischemia / epidemiology
  • Brain Ischemia / prevention & control
  • Cerebral Hemorrhage / chemically induced*
  • Cohort Studies
  • Female
  • Fibrinolytic Agents / adverse effects
  • Fibrinolytic Agents / therapeutic use
  • Humans
  • International Normalized Ratio
  • Male
  • Middle Aged
  • Proportional Hazards Models
  • Recurrence
  • Retrospective Studies
  • Risk Assessment
  • Stroke / epidemiology
  • Stroke / prevention & control
  • Time Factors
  • Warfarin / administration & dosage
  • Warfarin / adverse effects*
  • Warfarin / therapeutic use*


  • Anticoagulants
  • Fibrinolytic Agents
  • Warfarin