Body mass index is a risk factor for hemorrhagic transformation in older ischemic stroke patients after intravenous thrombolysis: a single center retrospective study

Background: The aim of our study was to determine whether body mass index is a predictor of hemorrhagic transformation in acute ischemic stroke patients after intravenous thrombolysis. Methods: A retrospective observational study was conducted to recruit 261 participants from a single center in China (67.0% males, median age 65 years). A head computed tomography scan was performed after 24 hours to evaluate hemorrhagic transformation occurrence, and a computed tomography scan was performed immediately in cases of clinical worsening. Multivariate logistic regression was used to estimate the association between risk factors and hemorrhagic transformation in acute ischemic stroke patients after intravenous administration of recombinant tissue plasminogen activator. Results: Of 261 patients, 40 (15.3%) developed hemorrhagic transformation (55% males, median age 70 years). Body mass index was higher in patients with hemorrhagic transformation than in patients without hemorrhagic transformation (25.7 vs 23.7; P value, 0.013). The multivariate logistic regression model showed that body mass index was an independent predictor of hemorrhagic transformation in patients aged ≥ 73 years (odds ratio, 1.74; 95% confidence interval, 1.22-2.49) but not in patients aged < 73 years (odds ratio, 1.01; 95% confidence interval, 0.87-1.18). In addition, the odds ratio was 5.16 (95% confidence interval, 2.21-12.04) when the body mass index was ≥ 25 kg/m2 compared to a body mass index < 25 kg/m2. Conclusions: The present study demonstrated that body mass index was an independent predictor of hemorrhagic transformation in older acute ischemic stroke patients after intravenous thrombolysis. Keywords: Body mass index, Hemorrhagic transformation, Intravenous thrombolysis, Ischemic stroke, Older patients.