BREAKING NEWS
A New Type of Diabetes
You may have seen headlines this week about a new type of diabetes. Experts are worried that people with diabetes arising from pancreatic diseases are being misdiagnosed, which may impact on a person’s long-term health and wellbeing.
What is type 3c diabetes?
Diabetes is classified as 1) insulin-dependent or type 1 diabetes, 2) non-insulin-dependent or type 2 diabetes, 3) gestational (pregnancy) diabetes and 4) diabetes associated with other syndromes/conditions. Type 3c diabetes (pancreatogenic diabetes or diabetes of the exocrine pancreas), as suggested by the name, refers to diabetes due to diseases of the exocrine pancreas (category four above). Decreased insulin production is a feature of type 3c diabetes. While type 3c diabetes may be news to the community at large at this time, researchers have hypothesised, for well over a decade, that non-endocrine pancreatic disease leads to the development of diabetes.
Which pancreatic diseases cause type 3c diabetes?
Pancreatitis (acute, relapsing or chronic pancreatitis of any cause), pancreatectomy/trauma, neoplasia, cystic fibrosis, hemochromatosis & fibrocalculous pancreatopathy) may lead to type 3c diabetes. Most (approx. 80%) cases arise following chronic pancreatitis (chronic inflammation of the pancreas that does not heal or improve, which worsens over time and leads to permanent damage).
What does the pancreas do?
The pancreas is an organ (or gland) located across the back of the abdomen, behind the stomach, which connects to the first section of the small intestine (the duodenum) at one end and the liver at the other. It mainly consists of exocrine tissue which produces pancreatic enzymes (digestive juices) which aid digestion. Around 5% of the pancreas is made up of endocrine cells (islets of Langerhans), which produce hormones that regulate pancreatic secretions and control blood sugar. Insulin is an important hormone produced by the pancreas. It’s secreted into the blood where it regulates the body’s glucose (sugar) levels.
What causes type 1 and type 2 diabetes?
Different causes give rise to types 1 and 2 diabetes. Type 1 diabetes is an autoimmune condition of unknown cause(s), where the body’s immune system destroys pancreatic insulin producing cells, eventually eliminating insulin production from the body. Type 2 diabetes is a progressive condition where the body becomes increasingly resistant to the normal effects of insulin and/or gradually loses the capacity to produce enough insulin.
Are there any other differences?
A number of other differences distinguish types 1, 2 and 3c diabetes, apart from differences in their underlying causes:
Type 1 Diabetes
Accounts for 10 – 15% of all cases of diabetes. Symptoms usually start in childhood or young adulthood and onset is very abrupt. Symptoms are very obvious (excessive thirst, increased urination, unexplained weight loss, weakness/fatigue, blurred vision), causing people to seek medical advice. Type 1 diabetes cannot be prevented or cured and it’s not linked to modifiable lifestyle factors.
Type 1 diabetes is managed with insulin injections given several times a day or delivered by an insulin pump. Episodes of low blood sugar levels (hypoglycaemia) are common.
Type 2 Diabetes
Accounts for 85 – 90% of all cases of diabetes. Type 2 diabetes develops over a long period of time. It occurs more often in people with a family history of type 2 diabetes and/or from certain ethnic backgrounds. Traditionally diagnosed in adults over 45, it is increasingly occurring at younger ages (ie children, adolescents & young adults). Some people have no symptoms at diagnosis, while others initially present with complications of diabetes (heart attack, vision problems, foot ulcer). Modifiable lifestyle factors are linked to type 2 diabetes and onset can be prevented or delayed by a healthy lifestyle.
Management initially includes lifestyle modification (regular physical activity, healthy eating & weight reduction) alone or in addition medications. As the condition tends to be progressive, over time most people need oral medications and/or insulin injections in addition to lifestyle changes.
Type 3e Diabetes
The true incidence of type 3e diabetes is unknown (estimated incidence: 5-10% in Western populations).
There are currently no management guidelines for type 3c diabetes. Even so, lifetime diabetes management and monitoring is imperative, as it is for people with types 1 or 2 diabetes, to avoid the long-term complications of diabetes.
What are the complications of diabetes?
People with diabetes, of any type, are at risk of microvascular and macrovascular complications caused by high blood sugar levels. Microvascular complications include damage to the eyes (retinopathy) which may lead to blindness, damage to the kidneys (nephropathy) leading to renal failure and need for dialysis and damage to nerves (neuropathy) leading to impotence and diabetic foot disorders (including infections leading to amputation). Macrovascular complications include cardiovascular diseases (heart attacks, strokes, insufficient blood flow to legs). Large randomized-controlled trials show that good control of blood sugar levels (metabolic control) in both types 1 and 2 diabetes can delay the onset and progression of diabetes related complications.
Why should I care about type 3 diabetes?
A recent UK study investigating the GP records of over 2.3 million Brits over 10 years, reported that diabetes arising from pancreatic diseases is more common than previously thought. In this study, the number of new onset type 3c diabetes cases exceeded type 1 diabetes cases. Only 2.7% of type 3c diabetes cases were correctly diagnosed, with most misdiagnosed as type 2 diabetes. Features of type 3c diabetes included poorer blood sugar control (glycaemic) and a more urgent need for insulin. Within 5 years, insulin use was around 4% in people with type 2 diabetes, 21% in people with type 3c diabetes following acute pancreatitis and 46% in people with diabetes following chronic pancreatitis.
These results emphasise the importance of early identification of type 3c diabetes. Early diagnosis will enable good blood glucose management which helps minimise potential diabetes complications (see above). Lastly, while type 1 and 2 diabetes increase the risk of developing pancreatic cancer, it is thought that type 3c diabetes signals future pancreatic cancer in at least 30% of people.
Further Reading
Article in The Australian (newspaper) http://www.theaustralian.com.au/news/latest-news/concern-type-3-diabetes-being-misdiagnosed/news-story/7c3810501e3b2f12530a86feb47bd90a
Read about the pancreas here https://www.medicalnewstoday.com/articles/10011.php
Original research paper https://www.ncbi.nlm.nih.gov/labs/articles/28860126/
[Note this is a medical paper]
Read about the medical management of type 3 diabetes here https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5003514/pdf/dmso-9-311.pdf
[Note this is a medical paper (2016 review)]