Traditionally, diabetes mellitus is broken down into two main types: type one and two. But there exists a recently identified third classification: Type 3c diabetes, which many in the public are unaware off. Also known as “Diabetes of the Exocrine Pancreas”, this rare sub-type of diabetes is caused mainly by pancreatic damage.

Researchers are worried that the lack of awareness towards Type 3c diabetes by both the public and healthcare professionals, have led to an increased likelihood of Type 3c diabetes being wrongly diagnosed as Type 2 diabetes. Part of the British research team’s latest study revealed that only 3% of people (from a sample of two million) were correctly identified as having Type 3c diabetes.

The newly identified Type 3c diabetes

Although all three types of diabetes mellitus occur due to the lack of insulin circulating within the system, they differ greatly in terms of mechanism, causation and treatment. Type 1 diabetes is caused by an autoimmune dysfunction leading to the body’s immune system destroying insulin producing cells of the pancreas. The condition usually develops early on in life (childhood or early adulthood) and will require insulin treatment. Meanwhile, Type 2 diabetes results from the pancreas’ inability to cope with the insulin demand of the body. In contrast, Type 2 diabetes usually occurs in older individuals and is associated with metabolic syndromes.

On the other hand, Type 3c diabetes occurs because of damage to the pancreas from inflammation (pancreatitis), tumour growths or pancreatic surgery. More than just the inability to produce insulin, Type 3c diabetes patients also have reduced production of pancreatic digestive enzymes; another hallmark of Type 3c diabetes.

Just as the treatment for Type 1 and Type 2 diabetes differs, so does the treatment for Type 3c diabetes. Nonetheless, the frequent misdiagnosis of Type 3c diabetes as Type 2 diabetes has resulted in incorrect treatment regime are not as effective at maintaining the patient’s blood surge levels.

“Several drugs used for Type 2 diabetes, such as gliclazide, may not be as effective in Type 3c diabetes,” remarked Andrew McGovern, one of the key researchers from the University of Surry carrying out the study on diabetes Type 3c. McGovern went on to add, “Misdiagnosis, therefore, can waste time and money attempting ineffective treatments while exposing the patient to high blood sugar levels.”

Patients with type 3c diabetes are more likely to require insulin to help control their blood sugar levels.
Patients with type 3c diabetes are more likely to require insulin to help control their blood sugar levels.

Unlike Type 1 and 2, patients with Type 3c diabetes require insulin and supplementary digestive enzymes. The digestive enzymes are usually taken as a tablet with meals and snacks. Early small studies have already shown that Type 3c diabetes patients can benefit greatly from this form of treatment.

Affected adults

Patients who have had a history of pancreatitis, pancreatic cancer and tumours and pancreatic surgery, were at a higher risk of developing Type 3c diabetes. Current data does not show the number of people with disease of pancreas who go on to develop diabetes, nor does it detail the duration between the pancreatic insult and the onset of Type 3c diabetes.

But surprisingly, the data does reveal that Type 3c diabetes is more common in adults than Type 1 diabetes. Among the study populations, 1% of all new cases of diabetes in adults were Type 1 diabetes compared to the marginally higher 1.6% for type 3c diabetes.

More worryingly, patients with Type 3c diabetes were twice as likely to have poorer blood sugar control than those with Type 2 diabetes. Much of this is attributed to the mechanism of Type 3c diabetes with patients being five to ten times more likely to require insulin to maintain a healthy blood sugar level.

For many patients unknowingly suffering from Type 3c diabetes, the duration between pancreatic injury and onset of diabetes may be more than a decade. McGovern explained, “This long lag may be one of the reasons the two events are not often thought of as being linked, and the diagnosis of Type 3c diabetes is being overlooked.”

While the thought of a new type of diabetes may be daunting for many, there is solace in knowing that it can be just as easily treated as Type 1 and 2 diabetes. At this point, the best thing the medical community can do is to improve its recognition and awareness of Type 3c diabetes. Taking a step in that direction, the American Diabetes Association has updated its Standards of Medical Care for 2017 to include “diseases of the exocrine pancreas” under “specific types of diabetes due to other causes”. MIMS

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