Considering the Importance of Personal and Injury Factors Influencing Outcome After Traumatic Brain Injury

Given the high variability in traumatic brain injury (TBI) outcomes and relative lack of examination of the influence of noninjury factors on outcome, this study aimed to examine factors associated with functional outcome at 1 and 2 years after moderate to severe TBI, including both preinjury and injury-related factors. Observational cohort study. Inpatient hospital recruitment with outpatient follow-up at 1 and 2 years post injury. Individuals with moderate to severe TBI were recruited prospectively into a Longitudinal Head Injury Outcome Study. Of the eligible 3253 individuals who were eligible, 1899 participants consented to the study (N=1899). Functional outcome was measured using the Glasgow Outcome Scale–Extended (GOS-E). 1476 participants (73.6% males) and 1365 participants (73% males) completed the GOS-E at 1 and 2 years post injury. They had a mean age at injury of 40 years and mean duration of post-traumatic amnesia (PTA) of 26 days. Good recovery, representing return to previous activities on the GOS-E (score 7-8), was present in 31% of participants at 1 year post injury and 33.5% at 2 years post injury. When predictor variables were entered into regression together, good outcome was significantly associated with not being from a culturally and linguistically diverse background and not having preinjury mental health or alcohol treatment, shorter PTA duration, and absence of limb injuries at both 1 and 2 years; higher education was also a significant predictor at 1 year post injury. Alongside consideration of injury severity, understanding and addressing preinjury factors is important to maximize outcomes.