Risk factors of hemorrhagic transformation in different locations and its relation to clinical outcomes of patients with acute ischemic stroke following intravenous thrombolysis

Abstract

To investigate the risk factors of hemorrhagic transformation (HT) in different cerebral regions and to explore its relation to clinical outcomes of patients with acute ischemic stroke after intravenous thrombolysis therapy. The clinical, laboratory, and radiological data of 292 consecutive acute ischemic stroke patients undergoing intravenous thrombolysis therapy in Second Affiliated Hospital, Zhejiang University School of Medicine from June 2009 to May 2013 was retrospectively analyzed. Deep HT was defined as HT located in basal ganglia, internal capsule, external capsule and thalamus, otherwise the lesion was defined as non-deep HT. Patients were divided into 3 groups [Deep HT(n=47), non-deep HT(n=82), non HT(n=8)] and the differences in clinical and demographic characteristics were compared by using one-way analysis of variance and Ξ2-test. Multivariable logistic regression models were used to determine the independent risk factors of HT in different cerebral regions and clinical outcomes. Age, baseline National Institutes of Health Stroke Scale (NIHSS) score, baseline systolic blood pressure and the frequency of atrial fibrillation were different among three groups. Logistic regression analysis revealed that baseline NIHSS score (OR=1.126, 95%CI:1.063-1.193, P<0.001) and baseline systolic blood pressure (OR=0.982, 95%CI:0.967-0.998, P=0.020) were independent risk factors of deep HT. Multivariate analysis also found that deep HT was an independent predictor of functional outcome after thrombolysis (OR=0.291, 95%CI:0.133-0.640, P=0.002). Baseline NIHSS score and systolic blood pressure are predictors for deep hemorrhagic transformation, which indicates the poor functional outcome of patients with acute ischemic stroke following thrombolytic therapy.