What is Type 3c Diabetes?


A group of scientists is warning that doctors need to be more aware of a type of diabetes that has been newly studied in recent years, which they say is poorly understood by many doctors and commonly misdiagnosed. As a result, patients with this form of diabetes, called Type 3c, often aren’t getting the treatment they need.

By way of review: Type 1 diabetes, which often shows up in childhood or early adulthood, is an autoimmune disease affecting the insulin-producing cells of the pancreas. Type 2 diabetes, which has generally been associated with middle-aged and older people, is caused by the body’s inability to use insulin properly.

Type 3c, described in a new study in the journal Diabetes Care, stems from damage to a previously healthy pancreas, caused by such health issues as pancreatitis, a pancreatic tumor, cystic fibrosis or trauma. As a result, the pancreas no longer produces adequate amounts of insulin, digestive enzymes and other hormones. According to some earlier journal articles on Type 3c, most of the cases occur among people with chronic pancreatitis.

Yet, according to the study by a group of British scientists, doctors routinely mistake Type 3c diabetes for Type 2. Writing in the website The Conversation, one of the researchers said the study found that only 3 percent of people with Type 3c diabetes were correctly diagnosed.

The mistake can be mean they’re not getting the treatment they need.

“Small studies in specialist centers have found that most people with Type 3c diabetes need insulin and, unlike other diabetes types, can also benefit from taking digestive enzymes with food,” wrote the researcher, Andrew McGovern at the University of Surrey.

In order to find patients with Type 3c, the researchers looked at close to 38,000 adult patients who had been newly diagnosed with diabetes, and examined their records to see which ones had experienced some kind of pancreatic disease such as pancreatitis before developing diabetes. The number came to 559—more than the number of Type 1 diabetes cases. Of these, all but a small number of patients had been wrongly diagnosed with Type 2 diabetes, and weren’t getting enough insulin for their needs.

Type 3 diabetes “has worse glycemic control and a markedly greater requirement for insulin,” the journal article concluded.

How is this mistake made? Possibly one cause is that, like Type 2 diabetes, Type 3c typically occurs later in life. The study found that the median age for Type 3c was 59. And according to McGovern’s article in The Conversationalist, there can be a delay between the earlier pancreatic problem and the later diabetes.

“We found that the onset of Type 3c diabetes could occur long after onset of pancreas injury,” he wrote. “In many cases, more than a decade later. 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.”

This isn’t the first time that medical experts have raised the issue of whether Type 3c diabetes is receiving the attention it needs.

A 2013 article in the European Journal of Internal Medicine estimated the prevalence of Type 3c at 5 to 10 percent of all people with diabetes in Western populations.

“Its prevalence and clinical importance have been underestimated and underappreciated so far,” the authors wrote. In addition to managing a more complicated need for insulin, they said, doctors should routinely test for other problems, such as vitamin D deficiency.

And a 2016 article in the journal Diabetes, Metabolic Syndrome and Obesity: Targets and Therapy noted that there are no common treatment guidelines for Type 3c, making it more difficult for doctors to determine the right course of action.

Type 3c is recognized by the American Diabetes Association, but a search of its website for information yields no results.

The scientists who have been researching the disease are raising concerns, year after year, that not enough attention is being paid to it.

In The Conversation, McGovern concludes: “Our findings highlight the urgent need for improved recognition and diagnosis of this surprisingly common type of diabetes.”


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2 years ago

I was told at age 63 I had #2 diabetes. I took Cymbalta for 6 yrs (which was a HUGE mistake) for the Fibromyalgia I also have. So, 6 yrs later and 60 lbs added to my body I was pushed into diabetes. It is in my family, my Mother’s side. My Dr put me on Metformin and Glipizide….well, my blood sugar STILL runs in the 200’s which is not normal!! Then I was given higher dose of Metformin, plus Januvia which I got bad side effects from both. Next we try Jardiance, it made me deathly sick!! Then I… Read more »

5 years ago

There is another cause of type 3c, I had what you explained prior to my total pancretectomy. But after my total pancreatectomy at the age of 17 due to hereditary pancreatitis it became a whole mother ball game. I act like a type 1 in sense of control and my BG are always a constant rollercoaster. At first they called me type 1 due to TP, doctors still have not caught on to the whole type 3c thing and I am usually the one informing them of it. I think it’s due to there not being a code for it… Read more »

3 years ago
Reply to  Katie

I have this type after losing my pancreas to cancer. Its very frustrating not to have resources and no doctors who know anything about this condition! Would love to hear from others!

2 years ago
Reply to  Ajalayer

I have diabetes from my Mom’s side of the family, have uncles,aunts,cousins who are or were # 1 and # 2 ……..then I have on my Dad’s side very little diabetes but 2 uncles, my Grandpa and a Aunt who all got pancreatic cancer. So, not very good odds for me. I never realized your pancreas could be removed and you live.

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