Warfarin-associated intracerebral hemorrhage after ischemic stroke.

Background And Purpose: The aim was to investigate the risk of intracerebral hemorrhage (ICH) in patients with ischemic stroke taking warfarin and whether this risk changed over time.

Methods: Between 2001 and 2008, the Swedish Stroke Register registered 12,790 patients with ischemic stroke discharged on warfarin. The patients was studied in two 4-year periods (inclusion 2001-2004: follow-up until 2005 and inclusion 2005-2008: follow-up until 2009) for which rates of subsequent ICH were calculated. Adjusted hazard ratios, comparing the second period with the first period, were estimated in Cox regression models.

Results: Of 6039 patients, 58 patients (1.0%) in the first period and 69 of 6751 patients (1.0%) in the second period had subsequent ICH. Annual rates of ICH ranged from 0.37% in the first period to 0.39% in the second period (adjusted hazard ratio, 1.04; 95% confidence interval, 0.73-1.48).

Conclusions: In this nationwide study, the risk of warfarin-associated ICH among ischemic stroke patients was low and did not change during the 2000s.