From the Department of Medical Sciences, Uppsala University, Uppsala, Sweden (S.Å., K.M.H., A.T.); Department of Statistics, Umeå University, Umeå, Sweden (M.E.); and AstraZeneca R&D, Mölndal, Sweden (K.M.H.). firstname.lastname@example.org.
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.
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.
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).
In this nationwide study, the risk of warfarin-associated ICH among ischemic stroke patients was low and did not change during the 2000s.