A systematic review of factors contributing to outcomes in patients with traumatic brain injury

Aim and objective. To review, systematically, factors contributing to outcomes in patients with traumatic brain injury. Background. Traumatic brain injury is a leading cause of death and disability. Several studies have determined the significant predictors of outcomes after traumatic brain injury. The comprehensive identification of these reliable factors for traumatic brain injury is critical to both clinical practice and research. Design. Systematic literature review. Methods. Eligible studies that combined at least two variables to predict outcomes in patient with traumatic brain injury were identified via electronic database searches, footnote chasing and contact with clinical experts. Quality of selected studies was assessed in terms of internal and external validity using 15 questions. Two reviewers independently examined titles, abstracts and whether each met the predefined inclusion criteria. Results. A total of 46 studies which met review criteria were finally selected. Most studies satisfied internal validity in terms of validity of research variables and multivariate analysis, but few were validated externally. The following factors were significantly associated with unfavourable outcomes: sociodemographic factors such as older age, male gender, lower level of education; clinical factors such as lower Glasgow Coma Scale score, injury caused by motor vehicle crash, hypotension, hypoxia, increased intracranial pressure, no pupil reaction, hypo‐ or hyperglycaemia, anaemia, coagulopathy, hypo‐ or hyperthermia, abnormal level of electrolytes, duration of coma; higher level of computed tomography classification by Marshall category; type of intracerebral lesions. Conclusion. Further studies on integrating the sociodemographic factors, the course of the clinical condition and a unified CT scoring system, are recommended for the evaluation and improvement of the prognosis of traumatic brain injury. Relevance to clinical practice. A systematic review of factors contributing to outcome for patients with traumatic brain injury will be invaluable in triage criteria, injury prognostication, care and discharge planning, resource use and patient and family counselling.