Hemorrhagic transformation in patients with acute ischaemic stroke and an indication for anticoagulation

Background and purpose: Intracerebral hemorrhage (ICH) can occur in patients following acute ischaemic stroke in the form of hemorrhagic transformation, and results in significant long-term morbidity and mortality. Anticoagulation theoretically increases risk. We evaluated stroke patients with an indication for anticoagulation to determine the factors associated with hemorrhagic transformation. Methods: Three-hundred and forty-five patients with ICD-9 codes indicating: (i) acute ischaemic stroke; and (ii) an indication for anticoagulation were screened. One-hundred and twenty-three met inclusion criteria. Data were collected retrospectively. Neuroimaging was reviewed for infarct volume and evidence of ICH. Hemorrhages were classified as: hemorrhagic conversion (petechiae) versus intracerebral hematoma (a space occupying lesion); symptomatic versus asymptomatic. Using multivariable logistic regression, we determined the hypothesized factors associated with intracerebral bleeding. Results: Age [odds ratio (OR)=1.50 per 10-year increment, 95% confidence interval (CI) 1.07-2.08], infarct volume (OR=1.10 per 10ccs, 95% CI 1.06-1.18) and worsening category of renal impairment by estimated glomerular filtration rate (eGFR; OR=1.95, 95% CI 1.04-3.66) were predictors of hemorrhagic transformation. Ninety- nine out of 123 patients were anticoagulated. Hemorrhage rates of patients on and off anticoagulation did not differ (25.3% vs. 20.8%; P=0.79); however, all intracerebral hematomas (n=7) and symptomatic bleeds (n=8) occurred in the anticoagulated group. Conclusions: The risk of hemorrhagic transformation in patients with acute ischaemic stroke and an indication for anticoagulation is multifactorial, and most closely associated with an individual's age, infarct volume and eGFR.