January 16, 2019 by Laura Pincus and Patty Shillington
Diabetes May Have 5 Types, New Study Suggests
While many people recognize the difference between type 1 and type 2 diabetes, a newly published study from northern Europe further categorizes diabetes into five distinct types.
Researchers analyzed data from nearly 9,000 diabetic patients in Sweden. They reviewed six variables to subdivide these patients into groups. The variables included the age of diabetes onset, the presence of known autoimmune antibodies, body mass index (BMI), levels of glycated hemoglobin (A1C) to determine average blood sugar over 12 weeks, pancreatic function in response to glucose and a measurement of insulin resistance based on that response. From this review, they named five categories of diabetes and suggested that the risk of complications and response to available treatments were determined by these variables.
5 Diabetes Types
Severe Autoimmune Diabetes (SAID)
Of these five categories, type 1 (also known as juvenile diabetes) and its adult-onset counterpart, known as latent autoimmune diabetes (LADA), would be grouped together as severe autoimmune diabetes, or SAID. In both conditions, insulin production in the pancreas stops in response to antibodies. Patients in this category benefit from insulin.
The other four categories named in the Swedish study re-classify conditions currently seen in type 2 diabetes.
Severe Insulin-Deficient Diabetes (SIDD)
The most severe of these types, researchers determined, is severe insulin-deficient diabetes, or SIDD. This condition mirrors type 1 diabetes in that there is little-to-no insulin produced, but the antibodies that would make it an autoimmune disease are lacking. Also, body mass index is not a factor in this condition. Researchers found that this group had the highest incidence of diabetic eye disease. They also determined this group likely would benefit from insulin therapy.
Severe Insulin-Resistant Diabetes (SIRD)
Researchers named a third condition as severe insulin-resistant diabetes, or SIRD. This condition had ties to obesity and showed a lack of response by the body’s cells to insulin. Patients with these characteristics, researchers found, were most susceptible to developing liver disease, chronic kidney disease and diabetic kidney disease. The research also indicated these patients would be helped most by diabetes medications, such as metformin, that prevent excessive sugar from entering the bloodstream.
Mild Obesity-Related Diabetes (MORD)
This mild form of diabetes is related to a high body mass index and can be managed effectively, researchers say, with diabetes medications and with diet, exercise and other lifestyle changes.
Mild Age-Related Diabetes (MARD)
This mild condition occurs with age, when the pancreas can’t keep up with the body’s demands for insulin. Like MORD, this type of diabetes is best controlled with medications and lifestyle changes.
A Doctor’s Reaction to the Study
“This categorization of diabetes isn’t really new, as we’ve known for some time that patients have not always fit exactly in either the type 1 or type 2 categories,” said Pascual De Santis, M.D., a Baptist Health Medical Group endocrinologist. “What’s helpful with this study is that it attempts to provide a tool for clinicians to make treatment decisions for those patients who haven’t fit into the traditional two types of diabetes. The categorization is attractive for research purposes and for future clinical practice as well.”
But, Dr. De Santis says that the application of this new research to clinical practice in North America is not likely to be soon. He says that there is little likelihood that doctors will have the same variables tested in this study available to them at the time they make a clinical decision. Additionally, he warns that the study was based on an analysis of a genetically similar population that does not resemble the American population.
“We still must look at individual patients’ ethnicity, body mass index, age, the presence of antibodies and how dramatic their symptoms are to determine the best course of treatment,” he said. “While this research attempts to replace our intuitive categorization of diabetes with a more systematic approach, at this point, clinical judgment still prevails.”