Frequency and determinants for hemorrhagic transformation of cerebral infarction.

Background: Frequency and associated risk factors for hemorrhagic transformation (HT), a worrying complication of ischemic stroke (IS), are not clearly defined. Our aim was to estimate the overall frequency and risk factors for HT in a hospital-based population. Methods: A retrospective review of medical records of patients discharged from our department during the period 2004-2006 with a diagnosis of anterior IS. Demographic, clinical and hematological information was collected. Uni- and multivariate logistic regression analyses were used to estimate risk for spontaneous HT. Results: We included 240 patients (125 males, 52%), mean age at admission was 72.5 years. HT was observed in 29 patients (12%). At univariate analysis, consciousness impairment at admission (OR 5.6, 95% CI 1.3-28.2), the presence of early CT signs (OR 2.4, 95% CI 1.1-5.3), infarcts of medium-large size (OR 11.3, 95% CI 4.1-30.8), cardioembolic stroke (OR 2.3, 95% CI 1.1-5.2) and low total cholesterol levels (OR 3.3, 95% CI 1.3-8.2) were significantly associated with HT. At multivariate analysis, only infarct size (OR 10.2, 95% CI 3.2-32.1) was still significantly associated with HT. Conclusions: Frequency of HT in our study was 12%. Consistently with previous results, HT was associated with the size of ischemic area. As patients included in our study did not receive thrombolytic therapy, our results are applicable to those patients whom clinicians, working in a hospital setting, usually deal with.