Type 1 diabetes rate high, but not getting worse
Australia has so far proved immune to the international trend toward rising rates of type 1 diabetes.
While the prevalence of type 1 diabetes in Australia is well above the developed country average, the national incidence of the lifelong condition has remained broadly stable since the turn of the century, unlike the experience in many other countries.
Type 1 diabetes data collated and analysed by the Australian Institute of Health and Welfare show that 2367 people were diagnosed with the disorder in 2011 – half of them aged 18 years or younger.
The rate of incidence in 2011 was 11.1 cases per 100,000, just a little above the annual average of 10.9 recorded between 2000 and 2011.
Institute spokeswoman Susana Senes said type 1 diabetes developed when the immune system destroyed insulin-producing cells in the pancreas. Researchers believe this is the result of an interaction between genetic and environmental factors, though it is still not known exactly what causes this to happen.
The AIHW figures highlight the extent to which the affliction, which requires regular doses of insulin to manage, appears in the early years of life.
Between 2000 and 2011, 22 per cent of all type 1 diabetes diagnoses were in people aged 19 years or younger, and a further 12 per cent were in people in their 20s.
By comparison, less than 9 per cent were diagnosed in their 30s, and little more than 4 per cent were 40 years or older.
The peak age group for diagnosis was the 10 to 14 years age group, where the rate of incidence reached 32 per 100,000 – a rate five times greater than that experienced among those in their early 40s, Ms Senes said.
While the rates of diagnosis have remained relatively stable, they are still high by international standards.
According to the AIHW, the average annual incidence of type 1 diabetes diagnosis among children aged 14 years or younger between 2000 and 2011 was 23 new cases per 100,000 children, compared with the OECD average of 17 per 100,000 – though the Australian rate was comparable to that in the United States and Canada.
The Institute’s analysis showed type 1 diabetes, like its type 2 cousin, is more common in men that women (incidence of 13 per 100,000 in males compared with 8 per 100,000 in females).
But it is less common among Indigenous Australian than the general population, and the incidence is greater in cities and large towns than in remote areas.