Adults diagnosed with type 2 diabetes in their 20s and 30s could be at greater risk of dying prematurely from a heart attack or stroke.

A study of nearly 750,000 Australians diagnosed with type 2 diabetes between 1997 and 2011 found the earlier the diagnosis, the higher their risk of dying from cardiovascular disease (CVD) or stroke.

During this 15-year period, those diagnosed with type 2 diabetes 10 years earlier than someone of the same age had a 30 to 60 per cent increased risk of death from any cause and from CVD respectively.

With the number of adolescents being diagnosed with diabetes increasing across the globe, the concerning findings have prompted calls for more “aggressive” intervention and prevention.

“Our findings suggest that younger onset type 2 diabetes increases mortality risk, and that this is mainly through earlier CVD mortality,” Professor Jonathan Shaw, Head of Clinical Diabetes Research at the Baker Institute said.

“Efforts to treat younger adults with type 2 diabetes more aggressively, and to delay the onset of type 2 diabetes might, therefore, reduce mortality,” he said.

Published in the journal Diabetologia, the study adds to a growing body of evidence suggesting earlier onset type 2 diabetes is associated with an increased risk of complications compared with later onset.

It’s not fully understood why age at diagnosis is related to mortality, although it’s thought the long exposure to toxic levels of glucose in the blood damages the heart.

“The biggest complication of having diabetes is having a heart attack… No organs like to be exposed to high glucose for a long time and people who have had it since their 20s have a long time of exposure,” lead author Professor Dianna Magliano said.

In Australia, those diagnosed with type 2 diabetes at age 10 to 39 years accounted for around nine per cent of all new cases in the year 2011.

The researchers warn similar trends have been found in many countries across the world “making young adults the fastest growing group for new onset type 2 diabetes”.

The good news is that simple lifestyle changes can prevent the onset of diabete, Professor Shaw said.

“A healthy diet and regular physical activity are essential tools at all ages to minimise the risks of developing diabetes and its cardiovascular complications. It should also be remembered that everyone can make a difference to their health trajectory by leading a healthy lifestyle,” he said.

-AAP