Incidence and epidemiology of aneurysmal subarachnoid haemorrhage in Australian Aboriginal and Torres Strait Islanders; a ten-year population study

Abstract

Health disparity between Aboriginal and Torres Strait Islander (ATSI) Australians and non ATSI Australians is well established. Incidence and epidemiology of aneurysmal subarachnoid haemorrhage (aSAH) in the ATSI population is less well described. An observational, cross-sectional study was conducted to identify all acute spontaneous subarachnoid haemorrhage in the Hunter New England and Mid North Coast population of New South Wales, Australia. Population and baseline information was obtained from the Australian Consens data. The size of the population was 1.1 million. Over the 9.8 year period, 959 admissions for subarachnoid haemorrhage were identified, of which, 531 were due to aneurysm rupture. The ATSI population represented 6 % of the study population and had a higher incidence of aSAH (11.5 per 100,000 person years’ vs 5.8 per 100,000 person years). The mean age at presentation was 8.6 years younger than the non-ATSI group (48.8 years vs 57.4 years). The ATSI population had higher rates of smoking and family history of aneurysms, but lower rates of premorbid hypertension. The overall rate of hospitalization for aneurysmal subarachnoid haemorrhage was higher in the indigenous Australian group, especially in younger patients. Higher smoking rates could be a contributing factor.