Most medics will tell you diabetes is split into two categories, type 1 and type 2. There are also a splattering of rarer diseases that could also be included under the diabetes banner, such as LADA and MODY.
But all that could be about to change. Researchers from Lund University Centre in Sweden and the Institute for Molecular Medicine Finland have found at least five clusters of diabetes, each with their own set of risks, symptoms, and causes. Future studies could add several more clusters to the list.
Group 1: Severe autoimmune diabetes (SAID), which affects otherwise healthy people from a young age. The body is unable to produce insulin.
Group 2: Severe insulin-deficient diabetes (SIDD), which is similar to SAID in terms of who it affects (the otherwise healthy young) but the immune system is not to blame.
Group 3: Severe insulin-resistant diabetes (SIRD), which affects overweight people who have built up severe insulin resistance.
Group 4: Mild obesity-related diabetes (MORD), which also affects overweight people but tends to develop earlier in life. It can be managed with lifestyle changes and metformin.
Group 5: Mild age-related diabetes (MARD), which affects the elderly and can also be managed with lifestyle changes and metformin. It is the largest of the five groups.
The team, led by Leif Groop, a professor of diabetes and endocrinology at Lund University in Sweden, came to this conclusion after monitoring the symptoms of 13,720 newly diagnosed patients aged 18 to 97. Their results were published in The Lancet Diabetes and Endocrinology earlier this week.
Diabetes is a chronic condition that is estimated to affect 425 million people worldwide. Though manageable, it is one of the leading causes of death, directly responsible for killing 1.6 million (2.8 percent) people in 2015.
The team hope this new research will help medics and patients manage the disease and alert them to possible complications their particular brand of diabetes might incur – for example, the team found that patients with group 2 diabetes appeared to be at greater risk of retinopathy, whereas patients with group 3 experienced the highest rates of kidney failure.
"This is the first step towards personalized treatment of diabetes,” Goop explained in a statement. "Current diagnostics and classification of diabetes are insufficient and unable to predict future complications or choice of treatment."
Victoria Salem, a consultant and clinical scientist at Imperial College London who was not involved in the study, agrees. "This is definitely the future of how we think about diabetes as a disease," she said in an interview with the BBC.
But she added, much more research was needed to explore these findings further. "There is still a massively unknown quantity – it may well be that worldwide there are 500 subgroups depending on genetic and local environment effects.”
The next step will be to embark on similar programs with people of different ethnic backgrounds. The researchers are already planning studies in China and India.