Over one million Australians are living with diabetes and 10% of these have type 1 diabetes mellitus (T1DM). The childhood incidence rate of T1DM in Australia (22.5 per 100,000 population) is one of the highest in the world [
1] and sits in the top 10 of countries compared across the globe [
2]. The population prevalence of type 2 diabetes mellitus (T2DM) in Australia is similar to European countries at 5%, however a higher incidence is seen in New Zealand (7.3%) and has also been demonstrated to be much higher in other countries, for example in Malaysia (17.9%) [
3]. Whilst the onset of T2DM is largely attributed to age and obesity with some evidence of predisposing genetic risk [
4], the aetiology of T1DM remains unknown. The process through which pancreatic beta cell destruction occurs is autoimmune however it is thought to occur in genetically susceptible individuals and a wide number of hypotheses regarding an environmental trigger have been studied but not yet proven [
5]. In Australia a higher prevalence of T2DM is known to be associated with low area socioeconomic status (SES) [
6] and potentially related to higher rates of obesity. In contrast to T2DM no association with low area SES has previously been demonstrated for T1DM [
7‐
9]. In Europe, Canada and the United States socioeconomically disadvantaged people have higher rates of morbidity and mortality in T1DM [
10‐
14]. However very little is currently known regarding T1DM prevalence in Australia and the disease outcome of treated end stage renal disease (ESRD) due to T1DM for people with low area SES, this regions Indigenous minority populations, Aboriginal and Torres Strait Islanders, and Maori and Pacific Islanders. This study is an exploration of social disparities in diabetes in relation to area SES and Aboriginal and Torres Strait Islander, Maori and Pacific Islander ethnicity.
In 2014, there were 25,626 people in Australia and New Zealand receiving renal replacement therapy for ESRD, and 37% of new cases (
n = 954) were attributed to diabetic nephropathy [
15]. In this region, people with low area SES are more likely to progress to ESRD due to kidney disease of any aetiology, but this disparity is most pronounced in diabetic nephropathy caused by T2DM [
16,
17] with a relative risk of progression to ESRD for the most disadvantaged decile versus the most advantaged decile of 2.38 [
17]. While studies from other countries have found a higher likelihood of ESRD due to T1DM for people with low SES [
18,
19] this has not previously been studied separately from T2DM in Australia. The incidence of T1DM in the Aboriginal and Torres Strait Islander population is reported to be 9 per 100,000 but this may be an underestimate because of lower levels of registration with the National Diabetes Services Scheme and underreporting of Indigenous status at diagnosis [
7]. Although the incidence of T1DM nephropathy has not previously been reported for Aboriginal and Torres Strait Islanders, Maori and Pacific Islanders, the incidence of progression to ESRD from chronic kidney disease in these populations due to any cause is much higher than the general population [
20]. It is also known that Aboriginal and Torres Strait Islanders, Maori and Pacific Islanders have a disproportionate burden of ESRD [
15] from diabetic nephropathy, which is attributed to a higher prevalence of T2DM but also to an increased likelihood of progressive renal disease [
20]. This has largely been attributed to individual behaviours [
20] however limited access to appropriate health care services is a strong determinant of health outcomes [
21].