Epidemiology, Clinical Characteristics and Outcomes of Patients With Severe Traumatic Brain Injury Treated by Emergency Medical Services in New Zealand: A Retrospective Observational Study

Abstract

AIM: This study aimed to characterise the epidemiology, clinical features and outcomes of adults with severe traumatic brain injury (sTBI) managed by emergency medical services (EMS) in New Zealand. Objectives included describing demographics, event and clinical characteristics, estimating national incidence, and 30-day mortality. METHODS: This retrospective observational study analysed EMS data from the Aotearoa New Zealand Paramedic Care Collection (ANZPaCC) between 1 January 2020 and 31 December 2022. Patients aged ≥16 years with head injury and a Glasgow Coma Scale score ≤8 were included. Descriptive statistics and age-standardised incidence rates were calculated by sex, ethnicity, age, rurality and socio-economic deprivation. RESULTS: EMS attended 630 sTBI patients over 3 years; most were male (n=430, 68.3%) and of European/Other ethnicity (n=398, 63.2%). sTBI incidence was higher among Māori than non-Māori (44.5-68.7 versus 28.6-35.6 per 100,000 person-years). Younger adults (≤45 years) had the highest rates. sTBIs in urban areas (n=485, 77%) and the most deprived quintile (n=213, 33.8%) were over-represented. Falls (n=217, 34.4%) and road traffic incidents (n=196, 31.0%) were the leading mechanisms. Thirty-day mortality was 37.8% (n=238). CONCLUSION: EMS working diagnoses of sTBI provide a valuable perspective on patient needs at the point of injury, capturing cases that may be missed in hospital-based datasets yet still influence transport decisions, destination selection and tertiary healthcare capacity. The data indicate that sTBI disproportionately affects Māori, younger adults, individuals living in socio-economically deprived areas and urban populations, highlighting health inequities and the need for targeted interventions, informed service planning and further research.