In a journal article published today in The Lancet, Professor Edwin Gale of the University of Bristol in the United Kingdom questions the current clinical definition and categorization of type 2 diabetes saying, “Type 2 diabetes is a disease in search of a definition. It has no hallmark clinical features, is generally diagnosed by default (no other cause for diabetes being evident)…”, he goes on to explain that people who are diagnosed with Type 2 diabetes don’t all have the same symptoms prior to diagnosis, and these symptoms vary widely between populations in clinical presentation and consequences; yet despite this, laboratory and clinical research is typically done as if type 2 diabetes were one disease with uniform characteristics.
Although what he is saying is not new, I think it is clinically relevant and timely. And I agree with him. As researchers and physicians, we can’t seem to fully understand the cause of type 2 diabetes and this is likely due to the fact that we are inappropriately lumping together several (if not many) different types of diabetes.
Our definition of type 2 diabetes is definitely too broad and I believe it is really several diseases that have a common denominator, hyperglycemia, or high blood sugar. In his article Dr. Gale proposes that until the origin of type 2 diabetes is understood, the name of type 2 diabetes should be changed to “idiopathic hyperglycemia,” and while I agree that a more descriptive term should be used to define the type of diabetes a patient has, I am not sure that, by itself, would be enough. We really need to do a better job in characterizing and studying these different types of diabetes in the research setting.
Because there are likely different forms of type 2 diabetes, in my practice I see a lot of variation in how the disease presents and progresses in my patients, but the effect on how I treat patients is not as significant as one could imagine. There is no single best treatment for diabetes and we have a limited number of therapies to offer patients. We frequently try them empirically, one after another, based upon what has been observed about their effectiveness over time. However, in the future as more therapies are developed, I think it will become imperative to know what type of diabetes we are dealing with more specifically, as the treatment may differ from type to type as we learn more, or the risk /benefit ratio or cost will require physicians to better select a patient for any given drug.
Right now I think our treatment guidelines for type 2 diabetes are rather loose and rely heavily on experience. However, until we better understand the different characteristics of type 2 diabetes we will not able to make more individual recommendations in the form of guidelines. So, in the meantime, treatments remain based upon physicians’ clinical experiences.