As we enter National Diabetes Week, the long-term future of diabetes management in Australia is very much up for debate.
At the same time, we have a Parliamentary inquiry into diabetes care, as well as tenders for items on the National Diabetes Services Scheme (NDSS).
This year, Diabetes Australia is using National Diabetes Week to kick start Australia’s biggest conversation about the impact of diabetes in this country.
It is a conversation that is becoming of increasing importance. A 2017 global study of the epidemiology of type 2 diabetes found that while it is already the most common diabetes diagnosis, type 2 continues to increase in prevalence, incidence, and as a leading cause of human suffering and death.
At its core, diabetes is a condition where there is too much glucose in the blood. The body can’t make insulin, enough insulin or is not effectively using the insulin it does make.
Over time high glucose levels can damage blood vessels and nerves, resulting in long term health complications including heart, kidney, eye and foot damage.
In Australia, diabetes is usually detected using a simple blood test. Normally, a blood sample is taken from your vein and sent to a pathology lab for analysis.
Dr Ailie Connell, the Head of Unit, Chemical Pathology for Eastern Health, sat down with London Agency to discuss the importance of pathology in diagnosing and managing patients living with diabetes.
London Agency: What type of testing do you use to diagnose diabetes and why?
Dr Connell: We do two main tests to diagnose diabetes. In the general population, the most commonly used test is called an HbA1c. It measures how much glucose is stuck to your haemoglobin – a protein found in red blood cells.
The more glucose in your blood, the more is stuck to the haemoglobin, the higher the HbA1c is. Above a certain threshold – 48 mmol/mol (7%), this gives us the diagnosis of diabetes. This test can be done at any time of day, fed or fasted.
The other main test is used primarily in pregnancy, to diagnose Gestational Diabetes. This is called an oral Glucose Tolerance Test (oGTT or GTT for short). The patient must be fasting (for between 8 and 16 hours), and when they arrive, they have their blood taken, then they must drink a sugary drink – more sugary than most people have their cordial!
They then need to have two more blood tests – 1 hour after the drink, and 2 hours after, to see how their body responds to the glucose in the drink. As you can imagine, this is not a very popular test – we are always looking for alternate ways to diagnose Gestational Diabetes!
HbA1c testing is seen as the standard and the most utilised (MBS) service for diabetes diagnostic testing. Can you speak to how this test helps you in your work?
The previous method of testing for diabetes -an oGTT for everyone, was unpleasant, labour intensive, and very easy to do poorly.
Using the HbA1c test makes the work of our blood collectors simpler and more efficient, gives the lab one test instead of three to perform, and of course, is much better tolerated by the patient, which means they are more likely to have the test done, and be diagnosed early. Early diagnosis and management improves the outcomes for patients.
How important is the relationship between pathology and patient management of diabetes?
Patients like to know their HbA1c every three months – it gives them a yardstick, and a goal to work towards. A patient presented with an HbA1c under 7% will celebrate a little, and feel a sense of achievement and control of their diabetes.
Are there any misconceptions around pathology and its role in diabetes management?
Because getting a HbA1c result is “routine” for most doctors and patients, they do not know the work we do to ensure that the patient has a correct result, in a timely fashion.
There are many things that can falsely lower or raise a HbA1c, and it is our job to identify them. We also work hard to ensure our analysers are running perfectly, and I don’t think people see that aspect.
Are we seeing an increase in diabetes diagnosis?
Absolutely! There are two factors here. Firstly, a lovely study done in Fremantle, WA, showed that although (at the time) 8% of the population had diabetes, only around 4% were diagnosed.
Since that paper came out – although it is many years ago today – an increased awareness and testing hopefully means we are getting more people their diagnosis, and earlier, which will improve their long-term outcomes.
Secondly, it seems very likely that the absolute numbers of people with diabetes in the community – both diagnosed and not yet diagnosed – is also increasing.
We live in an obesogenic environment and the Australian Institute of Health and Welfare has shown that the number of overweight and obese people is increasing.
Obesity is one of the causes of type 2 diabetes, so it seems that diabetes would also be increasing, increasing the diagnosis rate.
How much harder would diabetes diagnosis and management be without pathology? Could you even do it?
I guess you would be using clinical history and examination to diagnose diabetes, however the symptoms come on slowly and subtly, so frequently by the time one had symptoms clear enough to make the diagnosis, it would be a late diagnosis, and the patient would be at much higher risk of complications.
In management, too, it would be hard to do without pathology. The doctor would have to base it on symptoms, so a patient’s HbA1c would be much harder. And pathology sits all through the management of diabetes.
We use tests for protein in the urine to measure kidney damage, we check lipids to reduce another risk factor for heart disease and stroke, and when the type of diabetes is not certain, we look for antibodies and hormone levels to try to define whether the diabetes is Type 1 or Type 2.
