After an intracerebral hemorrhage, the risk of recurrent hemorrhage when warfarin is restarted may be lower than the risk of VTE if warfarin therapy is not reinitiated, investigators report.

After an intracerebral hemorrhage (ICH) necessitates warfarin discontinuation, the risk of recurrent hemorrhage when warfarin is restarted may be lower than the risk of thromboembolic events if warfarin therapy is not reinitiated, investigators report.

"However," the study team at the Mayo Clinic, Rochester, Minnesota advises in the October issue of the Archives of Neurology, "the clinician deciding whether to restart anticoagulation therapy after an episode of warfarin-associated ICH should weigh other factors, including the patient's risk of falls, general medical condition, and other risk factors for systemic hemorrhage."

"Patients without these risks may benefit from reinstitution of warfarin therapy. Failure to do so might unnecessarily subject them to thromboembolic complications," Dr. Daniel O. Claassen and colleagues advise.

They compared the outcome of 23 patients who restarted warfarin therapy with those of 25 patients who did not restart therapy after a warfarin-associated ICH.

The mean follow up was 43 months (range, 1-108 months), which is apparently the longest clinical follow-up of patients presenting with warfarin-associated ICH.

Of the 23 patients who resumed warfarin, one had a recurrent nontraumatic warfarin-associated ICH, two had traumatic intracerebral hemorrhages, and two had major extracranial hemorrhages. Of the 25 patients who did not restart warfarin, three had a thromboembolic stroke, one had a pulmonary embolism, and one had a distal arterial embolus.

"Our study results confirm the poor outcomes of patients with warfarin-associated ICH and the frequent adverse effects attributable to warfarin," the investigators write.

Dr. Claassen and colleagues note that "although there were no statistically significant differences, the observational results of our study suggest that recurrent primary ICH after reinstitution of warfarin therapy occurs less frequently than does recurrent thromboembolic events in patients who do not restart warfarin therapy."

However, "reinitiating anticoagulation therapy was also associated with an increased risk of traumatic ICH and extracranial hemorrhagic complications," they add.

Arch Neurol 2008;65:1313-1318