Swedish scientists are challenging how we think of diabetes, suggesting it is five conditions instead of two, and paving the way for more personalised treatment.

“Current diagnostics and classification of diabetes are insufficient and unable to predict future complications or choice of treatment,” says Leif Groop, a physician and professor of diabetes and endocrinology at Lund University in Sweden. Groop initiated the study of 13,720 newly diagnosed diabetes patients between ages 18 to 97. Groop’s team collated the measurements of insulin resistance, insulin secretion, blood sugar levels (BMI, HbA1c, GADA, HOMA-B and HOMA-IR), age of diagnosis, and more, over a decade, to develop five distinct new types of diabetes that he believes more accurately define the disease.

“Today, diagnoses are performed by measuring blood sugar. A more accurate diagnosis can be made by also considering the factors accounted for in [the new categorisation],” Groop says, specifically, the unique secondary diseases that often accompany diabetes, which the team used to define the new categories:

• Group 1: Severe autoimmune diabetes. This type would correspond to Type 1 diabetes and a rarer subtype, called latent autoimmune diabetes. This type of diabetes tends to occur at an early age with poor metabolic control, impaired insulin production, as well as with the presence of GADA antibodies.
• Group 2: Severe insulin-deficient diabetes. This group would include patients with high HbA1C, impaired insulin secretion, moderate insulin resistance, and a high incidence of retinopathy, a diabetic eye disease.
• Group 3: Severe insulin-resistant diabetes. This type of diabetes would be characterised by obesity and severe insulin resistance. In the study, this group had the highest incidence of kidney damage, a common secondary disease.
• Group 4: Mild obesity-related diabetes. This group would include obese patients who fall ill with diabetes at a relatively young age.
• Group 5: Mild age-related diabetes. Group 5 would form the largest group (about 40% of all global cases by Groop’s estimate) and consist of the most elderly patients.

Groop says patients who would fall into Group 3 stand to gain the most from this new categorisation, as they are currently the most likely to be treated incorrectly.

“This will enable earlier treatment to prevent complications in patients who are most at risk of being affected,” says the study’s lead author, Emma Ahlqvist, of Lund University.

The researchers expanded the analysis in studies spanning Sweden and Finland, finding similar conclusions. They plan to launch similar studies in China and India, to determine if this categorisation holds up for patients of different ethnic backgrounds — some of which (Indians) are ethnically more prone to insulin resistance. India has earned the dubious nickname of ‘diabetes capital of the world,’ with 10.4% of the population diagnosed with either Type 1 diabetes, Type 2 diabetes, or one of the handful of rarer versions of the disease, such as LADA, MODY and secondary diabetes.

Whether or not this new definition of diabetes is ever adopted by the World Health Organization or national bodies, it’s encouraging to see researchers thinking outside the box to address a public health problem that only shows signs of growing — especially since two-thirds of the most popular diabetes medicines in India are less than effective.