Diabetes
Type 2 diabetes is a significant health problem among Indigenous people, but it is not possible to reach a single estimate of the prevalence. Mortality statistics provide an indication of the substantial impact of diabetes among Indigenous people, and despite their limitations, hospitalisation data also confirm the much greater impact of the condition among Indigenous people than non-Indigenous people.
Extent of diabetes among Indigenous people
Diabetes/high sugar levels were reported by 6% of Indigenous people who participated in the 2004-2005 NATSIHS [1]. These problems were reported more frequently by Indigenous people living in remote areas (9%) than by those living in non-remote areas (5%). The proportions represent a slight, but not statistically significant, increase from those reported to the 2001 NHS. Bearing in mind the fact that for every person with identified diabetes there is likely to be another person with diabetes not yet diagnosed, these estimates are similar to those made in a major review of evidence from a variety of epidemiological studies that concluded that the overall prevalence among Indigenous people was between 10% and 30% [2].
After adjusting for differences in the age structures of the two populations, diabetes/high sugar levels were around 3.4 times more common for Indigenous than for non-Indigenous people [1]. The ratio between Indigenous and non-Indigenous females (4.1) was higher than that between Indigenous and non-Indigenous males (2.9).
Overall, a lower proportion of Torres Strait Islander (5%) than Aboriginal people (6%) reported having diabetes/high sugar levels (the difference is not statistically significant), but the proportion was 11% for Torres Strait Islanders living in the Torres Strait area [1].
The prevalence of diabetes increases with age, with the increase occurring at much younger ages among Indigenous people – the prevalence reported by Indigenous people aged 35-44 years was around 5 times that reported by non-Indigenous people (Table 1) [1].
Table 1 Diabetes: proportions of people reporting diabetes/high sugar levels as a 'long-term health condition', by Indigenous status, and Indigenous:non-Indigenous ratios, Australia, 2004-2005
Age group (years) |
Indigenous people |
Non-Indigenous people |
Ratio |
15-24 |
1.0 |
0.5 |
2.0 |
25-34 |
4.3 |
0.6 |
7.2 |
35-44 |
10.0 |
2.0 |
5.0 |
45-54 |
20.7 |
4.0 |
5.2 |
55+ |
32.1 |
11.6 |
2.8 |
Source: Australian Bureau of Statistics, 2006 [1]
Note: Ratio is the Indigenous proportion divided by the non-Indigenous proportion.
Few reports have been published about gestational diabetes mellitus (GDM), but information from the Northern Territory Midwives’ Collection found that around 6.3% of Indigenous women in the Territory developed GDM, compared with 4.1% of non-Indigenous women [4]. After allowance is made for the younger ages generally of the Indigenous women compared with the non-Indigenous women, the level of GDM among Indigenous women was 2.3 times that among non-Indigenous women.
As is the case with most health conditions, hospitalisation rates are not an accurate reflection of the burden of diabetes in the community. This is reflected in the fact that diabetes was recorded as the principal diagnosis in only 2% of episodes of hospitalisation for both Indigenous males and females in 2003-04 [5]. Of these episodes, 17% were for type 1 diabetes. (Of course, diabetes also contributed to many other episodes of hospitalisation, for which it wasn't recorded as the principal diagnosis.)
Despite this limitation of the data, the higher levels of diabetes among Indigenous than among non-Indigenous people are reflected in hospitalisation figures. Australia-wide in 2003-04, age-adjusted hospitalisation rates of Indigenous males and females for type 2 diabetes as the principal diagnosis were eight and ten times higher than those of non-Indigenous males and females [5]. As well as admissions for diabetes as a principal diagnosis, the condition was also reported frequently as an additional diagnosis in admissions for care involving dialysis, cardiovascular disease (including ischaemic heart disease and stroke), respiratory disease, and for bacterial diseases.
Diabetes is a major contributor to Indigenous mortality, being responsible for more than 8% of deaths of Indigenous people living in Qld, WA, SA and the NT in 1999-2003 [6]. The numbers of deaths from ‘endocrine, nutritional and metabolic diseases’ (almost 90% of which were due to diabetes) were 7.5 times higher for Indigenous males than the number expected from rates for non-Indigenous males and 10.5 times higher than expected for Indigenous females. Among people aged 35-54 years, the death rate of Indigenous males was between 23 times the rate of non-Indigenous males and the rate of Indigenous females 37 times that of non-Indigenous females [6].
References
1 Australian Bureau of Statistics (2006) National Aboriginal and Torres Strait Islander Health Survey, Australia 2004-05. (ABS Cat. no. 4715.0) Canberra: Australian Bureau of Statistics
2 De Courten M, Hodge A, et al. (1998) Review of the epidemiology, aetiology, pathogenesis and preventability of diabetes in Aboriginal and Torres Strait Islander populations. Canberra: Commonwealth Department of Health and Family Services
3 Australian Bureau of Statistics (2003) Australian demographic statistics quarterly: March quarter 2003. (ABS catalogue no. 3101.0) Canberra: Australian Bureau of Statistics
4 Markey P, Weeramanthri T, Guthridge S (1996) Diabetes in the Northern Territory. Darwin: Diabetes Australia, Northern Territory
5 Australian Institute of Health and Welfare (2005) Australian hospital statistics 2003-04. (Health service series no. 23) Canberra: Australian Institute of Health and Welfare
6 Australian Bureau of Statistics, Australian Institute of Health and Welfare (2005) The health and welfare of Australia's Aboriginal and Torres Strait Islander peoples 2005. (ABS catalogue no. 4704.0) Canberra: Australian Institute of Health and Welfare and the Australian Bureau of Statistics
This web site contains PDF documents that require the most current version of Adobe Reader to view. To download click on the icon below.
