A warning that Asians are developing diabetes at very much younger age
Researchers at CUHK Medicine are warning that Asia has become the centre of a global epidemic of obesity and diabetes. Globally, some 415 million people were affected by diabetes in 2015, with an estimated 100 million in China alone.
What is more worrying, researchers add, is that people who get diabetes in Asia are not that overweight as compared with their counterparts in Europe and the US.
The Faculty has had more than 20 years of experience in research involving the understanding of the epidemiology of diabetes in Asia and has made substantial contributions to the prevention and treatment of diabetes and its complications.
But the work is continuing more vigorously than ever to study why Asia is at the centre of this global epidemic.
Professor Ronald MA from the Department of Medicine and Therapeutics and his team are now trying to find out why Asians who are not overweight or obese are falling victim to diabetes. ‘We are interested in finding out what it is… is it genetic, is it related to diet or to some environmental factors that are present, for example, pollutants?’, Professor MA says.
One particular area of concern for the scientists is that people in Asia are developing diabetes at a very much younger age.
Researchers at CUHK led a very large multi-national study in 2014 in which they evaluated more than 40,000 individuals with diabetes in nine Asian countries or regions and discovered, surprisingly, that about one-fifth of people with diabetes in these different countries were diagnosed before they reached the age of 40. In western countries most people diagnosed with diabetes are much older.
‘This finding has a very important bearing’, says Professor MA, ‘because those who get diabetes at a younger age are going be to exposed to high glucose for a long period of their life and, therefore, face increased risk of complications associated with diabetes, such as kidney damage and cardiovascular disease.’
Studies show that in general people with diabetes are two to four times more likely to suffer a heart attack or stroke.
And, what many don’t realise is that people with diabetes also have an increased risk of getting cancers, including liver cancer or colorectal cancer, Professor MA adds. Diabetes is also the leading cause of blindness in adults.
According to local statistics, complications arising from diabetes, such as kidney disease and heart disease, account for more than 50 percent of deaths and account for a very high proportion of healthcare costs associated with the management of diabetes.
In order to combat the rising burden associated with diabetes-related complications, one major research programme currently underway is focused on discovering genetic factors and other biomarkers than can predict the risk of diabetic complications. This multi-disciplinary project, led by Professor MA, is supported by the Theme-based research scheme from the University Grants Committee, and involves more than 40 researchers from CUHK as well as from other overseas collaborating research institutes. This project leverages on clinical data and samples accumulated over a 20-year period, and aims to transform the delivery of diabetes care so that treatment can be better individualized, as well as providing new insights for developing new drugs to treat diabetes and its complications.
For more than a decade, diabetes researchers at CUHK have sought to use genetic studies to improve our understanding of how best to prevent and treat diabetes and its related complications, and the characteristics that make Asians particularly prone to developing diabetes.
In 2013, the group discovered that a genetic variant - near a gene called PAX4 - is an important genetic factor for Type 2 diabetes for Asians. PAX4 is very important for the development of the pancreas and beta cells which are particularly important because they make insulin.
‘And we found that Asians have a higher risk of having this genetic variation near PAX4, thus making them at increased risk of diabetes and other complications associated with diabetes,’ Professor MA says.
This genetic variation, which is particularly common in the Asian population, is much less common in the European population.
There are presently around 80 genetic variants, or genetic factors, in the European population and comparatively few have been discovered in the Asian population, PAX4 being one of them. Professor MA is hoping to increase this list of Asian specific genetic variants in order to find out more.
‘It is important to note that not only are Asians at risk of getting diabetes, it is also a well-known fact that they are prone to kidney damage after developing diabetes’, Professor MA says. ‘So our research is focused on trying to find genes and other biomarkers that would allow us to identify who are at risk of developing kidney disease or who are at risk of developing cardiac disease so that we can tailor individual treatment for them - we call that personalised medicine or precision medicine.’
A question then arises…how does diet fit into all of this? A person’s diet is certainly an important risk factor for diabetes, says Professor MA. But it would be a matter of oversimplification to say that obesity and diabetes is simply a result of an unhealthy diet with high sugar, high calorie and high fat.
‘It’s more complicated than just saying yes, people who consume more sugary drinks, carbonated soda or fruit juices, for that matter, have a high risk of getting diabetes. Yes, we definitely need to educate the public and warn people against taking excessive sugar in their diet because it’s an important risk factor. But, it’s not the only risk factor,’ Professor MA stresses.
He points out that there are many people who are overweight but don’t get diabetes. This is partly because their pancreas can produce sufficient amounts of insulin to compensate. So the ability for the body to produce insulin is probably one of the most important determining factors for who will actually get diabetes. ‘Diabetes is very much a disease of both nature and nurture, a conflict or “mismatch” between our ancient genome and programmed physiology with our modern 21st Century lifestyle full of excesses,’ Professor MA notes. He believes that insights gained through studying the diabetes epidemic in Asia will have great implications on future strategies to treat and prevent diabetes globally.
Introduction of Research Team