Aims: Traumatic Brain Injury (TBI) and stroke are the main causes of acquired brain injury. The differences in demographic profiles of stroke and TBI suggest that high-quality epidemiological studies of the two be compared. This study examined incidence of stroke and TBI by age and ethnicity in New Zealand.
Methods: Incidence rates are presented by age and ethnicity from two New Zealand population-based epidemiological studies (Brain Injury Outcomes New Zealand In the Community (BIONIC); and Auckland Regional Outcomes of Stroke Studies (ARCOS-IV)).
Results: Males and females had similar stroke risk, while males had 2x relative risk of mild TBI and 3x the relative risk of moderate/severe TBI compared to females. More TBI cases (35.6%) were identified through non-medical sources compared to stroke (3%). Incidence of TBI was greater than 5 times that of stroke. New Zealand European/Pākehā had the highest TBI incidence when less than 5 years of age, while Māori had the highest incidence after five years of age. For stroke, Pacific people and Māori had higher incidences until 75-84 years, after which Europeans had higher incidence.
Conclusions: Differences in TBI and stroke incidence suggest targeting prevention very differently for the two groups. Incidence profiles suggest TBI is much more common; and a need to target males and those of Māori ethnicity for TBI prevention.