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Published on: June 18, 2021

Death and disability from warfarin-associated intracranial and extracranial hemorrhages

Margaret C Fang1, Alan S Go, Yuchiao Chang

  • 1The Department of Medicine, Hospitalist Group, University of California, San Francisco, Calif 94143, USA. mfang@medicine.ucsf.edu

The American Journal of Medicine
|August 7, 2007
PubMed

Insights

Warfarin-associated intracranial hemorrhages are far more deadly than extracranial ones, causing 90% of deaths and most disability in atrial fibrillation patients. Clinicians should prioritize intracranial hemorrhage risk when considering anticoagulation.

Area of Science:

  • Cardiology
  • Neurology
  • Pharmacology

Background:

  • Warfarin is a common anticoagulant for atrial fibrillation.
  • Hemorrhagic complications are a known risk of warfarin therapy.
  • Outcomes of warfarin-associated hemorrhages, particularly intracranial versus extracranial, are not well-defined.

Purpose of the Study:

  • To examine the rates of death and disability from warfarin-associated intracranial and extracranial hemorrhages.
  • To compare outcomes between intracranial and extracranial hemorrhages in patients with atrial fibrillation.

Main Methods:

  • A cohort of 13,559 adults with nonvalvular atrial fibrillation was assembled.
  • Patients hospitalized for warfarin-associated intracranial and major extracranial hemorrhage were identified.
  • Functional disability and 30-day mortality were assessed via medical chart review and death certificates.

Main Results:

  • Intracranial hemorrhages led to severe disability or death in 76% of patients at discharge, versus 3% for extracranial hemorrhages.
  • Of 40 deaths within 30 days, 88% resulted from intracranial hemorrhages.
  • Intracranial events were strongly associated with 30-day mortality (OR 20.8) compared to extracranial hemorrhages.

Conclusions:

  • Intracranial hemorrhages account for approximately 90% of warfarin-associated hemorrhage deaths in atrial fibrillation patients.
  • Intracranial hemorrhages cause the majority of disability among survivors.
  • The risk of intracranial hemorrhage should be weighed more heavily than all major hemorrhages when considering warfarin therapy.
Abstract

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