Stroke incidence and case-fatality among Indigenous and non-Indigenous populations in the Northern Territory of Australia, 1999-2011

Background: Stroke is a leading cause of death and disability in Australia. The impact of stroke on the Australia Indigenous people is, however, unclear.

Aim: This study describes hospital-based stroke incidence and case fatality in the Northern Territory population in Australia.

Methods: Retrospective study of Northern Territory residents with a first-ever stroke episode and case fatality among Northern Territory residents in 1999-2011.

Results: The rate ratio of age-adjusted stroke incidence between Indigenous and non-Indigenous populations was 2·8 for men and 2·7 for women, similar to those reported elsewhere in Australia. The rate ratio increased to 3·8 (95% confidence interval: 3·4-4·3) after adjusting for multiple risk factors. There was no change in annual incidence between 1999 and 2011 for either non-Indigenous (incidence rate ratio per year 1·01, 95% confidence interval: 1·00-1·03) or Indigenous people (incidence rate ratio: 1·00, 95% confidence interval: 0·98-1·02), although incidence did increase for non-Indigenous people in the 15-39 year age group (incidence rate ratio: 1·09, 95% confidence interval: 1·02-1·17) and for Indigenous people in the 40-64 year age group (incidence rate ratio: 1·03, 95% confidence interva1·00-1·06). The case fatality rate decreased from 22% in 1999 to 12% in 2011. In-hospital deaths were more common among; older and Indigenous people, for those with other chronic diseases, and from haemorrhagic stroke compared with ischemic stroke.

Conclusions: In the Northern Territory, as elsewhere in Australia, Indigenous Australians are more likely than other Australians to suffer a stroke. Lack of falling in incidence in the Northern Territory population highlights the importance for ongoing comprehensive primary and acute care in reducing risk factors and managing stroke patients.