Sex differences in mild traumatic brain injury: a multicenter propensity-matched two-year cohort analysis

Background Mild traumatic brain injury (mTBI) is often considered low risk, yet growing evidence suggests that outcomes may differ by sex, and when explored, also by gender. We examined sex-associated differences in structural injury, acute-care complications, and neuropsychiatric diagnoses for patients with mTBI. Methods This retrospective cohort study used the TriNetX Global Health Research Network to identify adults (≥18 years) diagnosed with mTBI (Glasgow Coma Scale 13–15) between 2010 and 2022. Patients were identified using ICD-10 codes (S06, S09, R40.2411–R40.2413), with exclusion of moderate and severe TBI. Outcomes were assessed at 1 month, 6 months, 1 year, and 2 years. Propensity score matching (1:1) was performed to balance demographic and clinical characteristics. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated using logistic regression. Results Among 26,829 patients with mTBI, 9,999 (37.3%) were female and 16,830 (62.7%) were male. After matching, 9,649 patients remained in each cohort. Female patients had significantly lower odds of intracranial lesions, including epidural hematoma (OR 0.59, 95% CI 0.46–0.76) and subdural hematoma (OR 0.79, 95% CI 0.73–0.87), as well as lower odds of mortality, intensive care unit admission, neurosurgical intervention, and systemic complications across follow-up. In contrast, females demonstrated higher odds of anxiety (OR range 1.86–1.95) and depression (OR range 1.63–1.81) at all time points. Conclusions In this large cohort, women with mTBI exhibited lower structural and acute-care burden but higher long-term neuropsychiatric sequelae. These findings highlight the importance of sex- and gender-informed approaches to acute risk stratification and longitudinal mental health follow-up after mTBI.