International consensus on diagnostic standards and reporting guidelines are needed urgently to address the spiralling global diabetes epidemic, says one of Australia’s most influential diabetes experts.
And Professor Paul Zimmet, Professor of Diabetes at Monash University warns against reliance on fasting blood plasma glucose alone to diagnose diabetes and prediabetes, saying it could miss up to 25% of diabetes cases – and a whopping 50-100% of prediabetes cases.
The founder of IDI and later Director Emeritus of the Baker IDI Heart and Diabetes Institute, and head of the WHO Collaborating Centre for the Epidemiology of Diabetes Mellitus, was talking to the limbic following the release of a paper he co-authored which reveals diabetes mellitus prevalence statistics are significantly under-represented.
“Diabetes mellitus is one of the most important public health challenges of the 21st century,” they wrote in the Perspectives section of Nature Reviews Endocrinology. “Until the past decade, it has been seriously underrated as a global health threat. Major gaps exist in efforts to comprehend the burden nationally and globally, especially in developing nations, due to a lack of accurate data for monitoring and surveillance.”
Professor Zimmet said he had no doubt that diabetes mellitus was one of the largest health epidemics the world had ever faced, collecting reliable data on the burden of the disease was needed for more than just awareness raising.
“We need to be able to allocate appropriate health resources to where they are needed, and to do this we must have reliable prevalence rates and uniform diagnostic criteria,” he told the limbic. “And we have to look at it in the overall context at a global level; otherwise it’s just apples and oranges.”
He said the problem was compounded by the range of different methods and criteria now used to diagnose diabetes mellitus, including fasting blood plasma glucose (FPG), haemoglobin A1c (HbA1c), and the oral glucose tolerance test (OGTT), and the fact that some ethnic groups have different benchmarks for blood glucose levels.
Professor Zimmet said the OGTT test, once considered the gold standard, had lost favour over the years, partly due to the fact that it required patients to attend a pathology clinic for more than two hours.
The FGP is a popular choice for many clinicians, but he points out that it may not always be the best single test.
“Not only does it under-diagnose, but it misses 25% of diabetes mellitus cases and prediabetes by about 50-100%,” he said. “We need to confirm that the haemoglobin A1c really aligns well with the glucose tolerance test and then it should be utilised if there is any doubt remaining after the FGP.”
While this may help improve diagnostics, he said it was only a short-term fix.
“We need to sit down and agree on a global set of standards for diagnosis and then establish a reporting process which will help us to accurately estimate the figures globally,” he said.
“This is an epidemic that needs urgent attention.”