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Dementia prevalence and incidence among the Indigenous and non-Indigenous populations of the Northern Territory

Med J Aust 2014; 200 (8): 465-469. || doi: 10.5694/mja13.11052

Summary

Objective: To estimate the prevalence and incidence of dementia in Northern Territory Indigenous and non-Indigenous populations.

Design, setting and participants: Four data sources were used to identify clients with a diagnosis of dementia, from 1 January 2008 to 31 December 2011. The data sources included hospital admissions, aged care services, primary care and death registration. A capture–recapture method was used to estimate prevalence and incidence, including both diagnosed and unknown cases.

Main outcome measures: Prevalence and incidence of dementia among the NT Indigenous and non-Indigenous populations.

Results: In 2011, the estimated prevalence in the NT Indigenous population aged 45 years and over was 3.7 per 100, and 1.1 per 100 in the corresponding NT non-Indigenous population. The age-adjusted prevalence for the NT Indigenous population was 6.5 per 100, compared with the NT non-Indigenous prevalence of 2.6 per 100, which was similar to the national rate. The prevalence rate ratios of NT Indigenous to NT non-Indigenous men and women, respectively, were: 6.5 and 5.5 for the 45–64-years age group, 4.0 and 4.1 for those aged 65–74 years and 2.1 and 1.9 for those aged 75 years and over. The age-adjusted incidence among the NT Indigenous population aged 45 years and over (27.3 per 1000 person-years) was higher than that among the NT non-Indigenous population (10.7 per 1000 person-years).

Conclusion: The NT Indigenous population has a much higher prevalence and incidence of dementia and younger onset of disease compared with their non-Indigenous counterparts. The results highlight the urgent need for interventions to moderate the emerging impact of dementia in the Australian Indigenous population.

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  • Shu Qin Li1
  • Steven L Guthridge1
  • Padmasiri Eswara Aratchige1
  • Michael P Lowe1
  • Zhiqiang Wang2
  • Yuejen Zhao1
  • Vicki Krause1

  • 1 Department of Health, Darwin, NT.
  • 2 School of Medicine, University of Queensland, Brisbane, QLD.

Correspondence: Shu.li@nt.gov.au

Acknowledgements: 

Zhiqiang Wang was supported by a National Health and Medical Research Council Fellowship (APP1042343).

Competing interests:

No relevant disclosures.

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