Does sexual dimorphism influence outcome of traumatic brain injury patients? The answer is no!

Background. The protective effect of female gender on posttraumatic mortality or acute complications after traumatic brain injury (TBI) has been postulated. This effect might be seen if TBIs were analyzed by severity. To assess potential gender effects, we performed a retrospective case-controlled study matching female patients to male counterparts for overall injury severity; hemodynamic status at admission; and head, chest, and abdomen Abbreviated Injury Scale score. Methods: All female patients sustaining TBI admitted over 6.5 years were reviewed. An overall comparison between women (n = 914) and their male matched counterparts (n = 916) was performed. Patients were then stratified according to the severity of head injury on the basis of admission Glasgow Coma Scale (GCS) score into three groups: group 1, GCS score of 13 to 15 (788 female patients, 769 male patients); group 2, GCS score of 9 to 12 (40 female patients, 42 male patients); and group 3, GCS score < 9 (63 female patients, 87 male patients). Cohorts were compared for mortality or the development of acute respiratory distress syndrome, pneumonia, and systemic sepsis using standard definitions. A subset analysis was performed excluding patients with age above 50 years (789 women, 811 men) to exclude the effects of menopause on the results. Results: There was no statistically significant difference in outcome overall or in subset analysis of mild (group 1), moderate (group 2), or severe (group 3) TBI. The exclusion of patients older than 50 years showed no protective effect of female gender on outcome. Conclusion: Gender does not play a role in posttraumatic mortality or in the incidence of acute complications after any degree of TBI.