Effects of Gender on Outcomes After Traumatic Brain Injury

Background: It has been reported that female gender may be an independent risk factor for poor outcome after traumatic brain injury (TBI). The goal of this study was to investigate gender differences in outcome after TBI. Methods: Between February 2002 and April 2010, 17 Austrian centers prospectively enrolled 863 patients with moderate and severe TBI into observational studies. Data on crash, treatment, and outcomes were collected. Data sets from patients who had isolated TBI were selected. Six-month outcomes were classified as "favorable" if Glasgow Outcome Scale scores were 5 or 4 and were classified as "unfavorable" if Glasgow Outcome Scale scores were 3 or less. The Rotterdam score was used to classify computed tomography (CT) findings. Univariate statistics (Fisher's exact test, t test, chi(2) test) and logistic regression were used to identify factors associated with hospital mortality and favorable outcome. Results: There were 134 female and 305 male patients. Hospital mortality was 39.6% for females and 32.5% for males (p = 0.16). Rates of unfavorable outcome were 58.7% for females and 53.4% for males (p = 0.09). There were no significant mortality differences between females and males for factors such as age groups, trauma mechanisms, Glasgow Coma Scale scores, lesions on the CT scan, or treatment factors. Logistic regression revealed that gender had no significant influence on mortality of unfavorable outcome. The differences in outcome were due to the higher mean age of females (61.4 vs. 50.4, p < 0.001) and possibly because of small differences in Glasgow Coma Scale scores and in CT scores. Conclusions: Female gender is not an independent risk factor for in-hospital mortality after TBI.