Traumatic brain injury (TBI) is a significant cause of disability, but little is known about sex and gender differences after TBI. We aimed to analyze the association between sex/gender, and the broad range of care pathways, treatment characteristics, and outcomes following mild and moderate/severe TBI. We performed mixed-effects regression analyses in the prospective multi-center Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study, stratified for injury severity and age, and adjusted for baseline characteristics. Outcomes were various care pathway and treatment variables, and 6-month measures of functional outcome, health-related quality of life (HRQoL), post-concussion symptoms (PCS), and mental health symptoms. The study included 2862 adults (36% women) with mild (mTBI; Glasgow Coma Scale [GCS] score 13–15), and 1333 adults (26% women) with moderate/severe TBI (GCS score 3–12). Women were less likely to be admitted to the intensive care unit (ICU; odds ratios [OR] 0.6, 95% confidence interval [CI]: 0.4-0.8) following mTBI. Following moderate/severe TBI, women had a shorter median hospital stay (OR 0.7, 95% CI: 0.5-1.0). Following mTBI, women had poorer outcomes; lower Glasgow Outcome Scale Extended (GOSE; OR 1.4, 95% CI: 1.2-1.6), lower generic and disease-specific HRQoL, and more severe PCS, depression, and anxiety. Among them, women under age 45 and above age 65 years showed worse 6-month outcomes compared with men of the same age. Following moderate/severe TBI, there was no difference in GOSE (OR 0.9, 95% CI: 0.7-1.2), but women reported more severe PCS (OR 1.7, 95% CI: 1.1-2.6). Men and women differ in care pathways and outcomes following TBI. Women generally report worse 6-month outcomes, but the size of differences depend on TBI severity and age. Future studies should examine factors that explain these differences.

Patients with mild traumatic brain injury (mTBI) are at risk for post-concussion (PC) symptoms and post-traumatic stress disorder (PTSD). The co-occurrence of PC and PTSD symptoms after mTBI in relation to health-related quality of life (HRQoL), health care utilization, and return to work has not yet been investigated. PC and PTSD symptoms were measured six months post-TBI by respectively the Rivermead Post-Concussion Symptoms Questionnaire (RPQ) and the Post-Traumatic Stress Disorder Checklist for DSM-5 (PCL-5). Of the 1566 individuals after mTBI who met the inclusion criteria, 26.1% experienced PC symptoms (RPQ ≥16). Additionally, 9.8% experienced PTSD symptoms (PCL-5 ≥ 33), of which the vast majority (81%) also reported experiencing PC symptoms. Differences between patients with no/mild symptoms, with only PC, only PTSD, and both PC and PTSD symptoms in HRQoL, return to work, and rehabilitation were analyzed using logistic and linear regression analyses. Patients with PC and/or PTSD symptoms reported lower HRQoL, higher rates of rehabilitation, and lower return to work rates compared to patients with no/mild symptoms. Patients with both PC and PTSD symptoms reported significantly lower HRQoL (B = −2.73, CI = −4.65; −0.83, p < 0.001) compared to those with only PC symptoms, while there were no significant differences in their ongoing rehabilitation care (OR = 1.39, CI = 0.77–2.49, p = 0.272) and return to work rates (OR = 0.49, CI = 0.15–1.63, p = 0.246) at six months. These results underline the importance of the diagnosis and appropriate treatment of patients with mTBI, experiencing PC and/or PTSD symptoms.

After mild traumatic brain injury (mTBI), a substantial proportion of individuals do not fully recover on the Glasgow Outcome Scale Extended (GOSE) or experience persistent post-concussion symptoms (PPCS). We aimed to develop prognostic models for the GOSE and PPCS at 6 months after mTBI and to assess the prognostic value of different categories of predictors (clinical variables; questionnaires; computed tomography [CT]; blood biomarkers). From the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study, we included participants aged 16 or older with Glasgow Coma Score (GCS) 13-15. We used ordinal logistic regression to model the relationship between predictors and the GOSE, and linear regression to model the relationship between predictors and the Rivermead Post-concussion Symptoms Questionnaire (RPQ) total score. First, we studied a pre-specified Core model. Next, we extended the Core model with other clinical and sociodemographic variables available at presentation (Clinical model). The Clinical model was then extended with variables assessed before discharge from hospital: early post-concussion symptoms, CT variables, biomarkers, or all three categories (extended models). In a subset of patients mostly discharged home from the emergency department, the Clinical model was extended with 2-3–week post-concussion and mental health symptoms. Predictors were selected based on Akaike's Information Criterion. Performance of ordinal models was expressed as a concordance index (C) and performance of linear models as proportion of variance explained (R2). Bootstrap validation was used to correct for optimism. We included 2376 mTBI patients with 6-month GOSE and 1605 patients with 6-month RPQ. The Core and Clinical models for GOSE showed moderate discrimination (C = 0.68 95% confidence interval 0.68 to 0.70 and C = 0.70[0.69 to 0.71], respectively) and injury severity was the strongest predictor. The extended models had better discriminative ability (C = 0.71[0.69 to 0.72] with early symptoms; 0.71[0.70 to 0.72] with CT variables or with blood biomarkers; 0.72[0.71 to 0.73] with all three categories). The performance of models for RPQ was modest (R2 = 4% Core; R2 = 9% Clinical), and extensions with early symptoms increased the R2 to 12%. The 2-3-week models had better performance for both outcomes in the subset of participants with these symptoms measured (C = 0.74 [0.71 to 0.78] vs. C = 0.63[0.61 to 0.67] for GOSE; R2 = 37% vs. 6% for RPQ). In conclusion, the models based on variables available before discharge have moderate performance for the prediction of GOSE and poor performance for the prediction of PPCS. Symptoms assessed at 2-3 weeks are required for better predictive ability of both outcomes. The performance of the proposed models should be examined in independent cohorts.

Background: Post-concussion symptoms (PCS) are often reported as consequences of mild and moderate traumatic brain injury (TBI), but these symptoms are not well documented in severe TBI. There is a lack of agreement as to which factors and covariates affect the occurrence, frequency, and intensity of PCS among TBI severity groups. The present study therefore aims to examine the association between sociodemographic, premorbid, and injury-related factors and PCS. Methods: A total of 1391 individuals (65% male) from the CENTER-TBI study were included in the analyses. The occurrence, frequency (number of PCS), and intensity (severity) of PCS were assessed using the Rivermead Post-concussion Symptoms Questionnaire (RPQ) at six months after TBI. To examine the association between selected factors (age, sex, living situation, employment status, educational background, injury and TBI severity, and premorbid problems) and PCS, a zero-inflated negative binomial model (ZINB) for occurrence and frequency of PCS and a standard negative binomial regression (NB) for intensity were applied. Results: Of the total sample, 72% of individuals after TBI reported suffering from some form of PCS, with fatigue being the most frequent among all TBI severity groups, followed by forgetfulness, and poor concentration. Different factors contributed to the probability of occurrence, frequency, and intensity of PCS. While the occurrence of PCS seemed to be independent of the age and sex of the individuals, both the frequency and intensity of PCS are associated with them. Both injury and TBI severity influence the occurrence and frequency of PCS, but are associated less with its intensity (except “acute” symptoms such as nausea, vomiting, and headaches). Analyses focusing on the mTBI subgroup only yielded results comparable to those of the total sample. Discussion: In line with previous studies, the results support a multifactorial etiology of PCS and show the importance of differentiating between their occurrence, frequency, and intensity to better provide appropriate treatment for individual subgroups with different symptoms (e.g., multiple PCS or more intense PCS). Although PCS often occur in mild to moderate TBI, individuals after severe TBI also suffer from PCS or post-concussion-like symptoms that require appropriate treatment. The chosen statistical approaches (i.e., ZINB and NB models) permit an ameliorated differentiation between outcomes (occurrence, frequency, and intensity of PCS) and should be used more widely in TBI research.

Background: Traumatic brain injury (TBI) is associated with an increased risk of major depressive disorder (MDD) and post-traumatic stress disorder (PTSD). We aimed to identify predictors and develop models for the prediction of depression and PTSD symptoms at 6 months post-TBI. Methods: We analysed data from the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury study. We used linear regression to model the relationship between predictors and depression (Patient Health Questionnaire-9) and PTSD symptoms (PTSD Checklist for Diagnostic and Statistical Manual for Mental Health Disorders Fifth Edition). Predictors were selected based on Akaike’s Information Criterion. Additionally, we fitted logistic models for the endpoints ‘probable MDD’ and ‘probable PTSD’. We also examined the incremental prognostic value of 2–3 weeks of symptoms. Results: We included 2163 adults (76% Glasgow Coma Scale=13–15). Depending on the scoring criteria, 7–18% screened positive for probable MDD and about 10% for probable PTSD. For both outcomes, the selected models included psychiatric history, employment status, sex, injury cause, alcohol intoxication and total injury severity; and for depression symptoms also preinjury health and education. The performance of the models was modest (proportion of explained variance=R ² 8% and 7% for depression and PTSD, respectively). Symptoms assessed at 2–3 weeks had a large incremental prognostic value (delta R ² =0.25, 95% CI 0.24 to 0.26 for depression symptoms; delta R ² =0.30, 95% CI 0.29 to 0.31 for PTSD). Conclusion: Preinjury characteristics, such as psychiatric history and unemployment, and injury characteristics, such as violent injury cause, can increase the risk of mental health problems after TBI. The identification of patients at risk should be guided by early screening of mental health.