OBJECTIVE: To determine the frequency, mechanism(s) and impact of recurrent traumatic brain injury (TBI) over a one year period.
DESIGN: Population-based TBI incidence and one-year outcomes study with embedded case control analysis. Participants: All participants (adults and children) who experienced a recurrent TBI (more than one) in the 12 months following an index injury and matched controls who sustained one TBI within the same period, enrolled in a population based TBI incidence and outcomes study.
METHODS: Details of all recurrent TBIs sustained within 12 months of the initial index injury were recorded. Each recurrent TBI case was matched to a case sustaining one TBI based on: age (±2 years), gender and index TBI severity. Cognitive ability, disability and post-concussion symptoms were assessed one year following the index injury.
RESULTS: 9.9% (n=72) of TBI cases experienced at least one recurrent TBI within the year following initial index injury. Males, people aged <35 years and those who had experienced a TBI prior to their index injury were at highest risk of recurrent TBI. Recurrent TBI cases reported significantly increased post-concussion symptoms at one year compared to the matched controls (n=72) sustaining one TBI. There was no difference in overall cognitive ability and disability between the two groups.
CONCLUSION: People experiencing recurrent TBIs are more likely to experience increased frequency and severity of post-concussion symptoms. Greater public awareness of the potential effects of recurrent brain injury is needed.