OBJECTIVE: To determine if there are longer-term impacts on symptoms, health status, mood and behaviour 10-years following a mild traumatic brain injury (mTBI).

DESIGN: Prospective cohort study

SETTING: Community-based, civilian sample

PARTICIPANTS: Adults aged ≥16 years at follow up who experienced a mTBI 10-years ago, and an age and sex-matched non-injured control group.

INTERVENTIONS: Not applicable

MAIN OUTCOME MEASURES: MTBI cases and controls were asked to complete self-report assessments of functioning (WHODAS 2.0), symptoms (Rivermead Post-Concussion Symptom Questionnaire), health status (100-point scale), alcohol (AUDIT-C) and substance use (ASSIST), and whether they had engaged in any anti-social behaviours over the past 12-months. RESULTS: Data were analysed for 368 participants (184 mTBI cases and 184 age-sex matched controls). Just over a third of mTBI cases (64, 34.8%) reported that they were still affected by their index mTBI 10-years later. After adjusting for education and ethnicity, the mTBI group had statistically higher overall symptom burden (F=22.32, p<0.001, ηp2 =0.07) compared to controls. This difference remained after excluding those who experienced a recurrent TBI. The mTBI group were more than three times as likely to have engaged in anti-social behaviour during the previous 12-months (F=5.89, p=0.02). There were no group differences in health status, functioning, or problematic alcohol or substance use 10-years post-injury.

CONCLUSIONS: This study provides evidence of potential longer-term associations between mTBI, post-concussion symptoms and anti-social behaviour which warrants further evaluation. Future research should also examine if longer-term effects may be preventable with access to early rehabilitation post-injury.