Why Type 1.5 Diabetes is Type 1 in Disguise

The common school of thought in diabetes treatment has always been simple: Children get Type 1 diabetes and adults get Type 2. Over the past 15 years, there has been a realization in the medical community that this isn’t always the case.

Type 1 diabetics’ bodies don’t produce enough insulin to change glucose in their blood into energy. Oftentimes, this deficiency shows up in children. In Type 2 diabetes, the body builds resistance to insulin so that oral medications are required to keep blood sugars in the proper range. Because this resistance occurs over time, it is typically found in adults.

Endocrinologists have come to realize that adults can essentially develop late-onset Type 1 diabetes, a medical gray area sometimes referred to as Type 1.5 diabetes.

Adults with Type 1 Diabetes

Colleen Julius, RN, was diagnosed with thyroid cancer in 2006. While going through treatment for cancer, Julius noticed she wasn’t recovering as quickly or as fully as expected.

“I’m wondering why don’t I feel better. I should be recovering better than this,” recalled Julius, now an RN at ProMedica’s Mary Ellen Falzone Diabetes Center on the ProMedica Toledo Hospital campus.

After visiting an endocrinologist, she discovered her blood glucose level was 560 mg/dl (under 100 is normal for a fasting adult, according to the American Diabetes Association) and an A1C test measuring blood sugar stated her score was 13. An A1C score of 6.5 indicates a person is diabetic.


Colleen Julius, RN

With doctors assuming she had Type 2 because she was an adult, Julius was sent home with oral medications to keep her blood sugar levels in check. Less than a year later, her body had stopped producing insulin and she discovered she was actually a latent autoimmune diabetic (LADA), which has come to be known as Type 1.5.

John Brunner, MD, endocrinologist at ProMedica Endocrine and Diabetes Care Center, said Type 1.5 is not a legitimate, medical term.

“It’s sort of a medical slang term for patients that don’t act clearly like Type 2, seem to be insulin deficient, but they’re not classic Type 1s in the sense that they didn’t develop it when they were juveniles,” he said. “Initially, because they’re still making insulin, they look like Type 2. But over time, as you follow them, you discover that none of the oral, non-insulin injectables work.”

Dr. Brunner continued, “These people are really Type 1s in an adult’s body. It’s autoimmune destruction of the pancreas islet cells, but it occurs later in life so they look like they might be Type 2s, but they’re really Type 1s in disguise.”

“These people are really Type 1s in an adult’s body…they’re really Type 1s in disguise.”

Misdiagnosis can present a life-threatening situation, said Dr. Brunner, who estimates about 10 to 15% of patients referred to the diabetes center have LADA or Type 1.5 diabetes.

“The problem is that everybody thinks that all Type 1s are juveniles,” he said. “But you can get Type 1 diabetes at any age. That presentation at an older age is not as cataclysmic as it is in children, but people look at older people with diabetes and assume they have Type 2 diabetes. You just can’t do that.”

Being an Advocate, Spreading Awareness

Brunner said he makes certain his older patients with LADA know they must be their own advocates and that under no circumstances are they to be taken off insulin.

“I tell them, ‘When someone stops your insulin, that can be a medical emergency.’ You never stop your insulin, because you could go into ketoacidosis (a potentially fatal buildup of acids that result from a lack of insulin).”

Being informed of how the condition affects the body can help diabetics get an early indication that something isn’t right and see the proper medical professional.

“If they’re having to go on two or three medications to control their blood sugar, or if they’re normal weight and they’re wondering, ‘Why is it so much harder for me to get this under control?’ they probably should see an endocrinologist and get things looked into further,” Julius said. “Family doctors aren’t always aware of the 1.5. It doesn’t come up on their radar very much; they don’t deal with it very often. An endocrinologist is going to see that a little bit more.”

Julius said having LADA has greatly benefited her in her work at the center, where she’s been employed for two years.

“They know I understand what they’re dealing with,” she said. “I tell them I’ve had it for 10 years and I know some of the pitfalls. When people say, ‘When I feel low, I feel like eating everything in sight.’ I say, ‘Yeah, I know, that’s how I feel.’ I think people tend to listen to me a little bit better because I have walked in their shoes.”

Julius said she is able to let patients know that diabetes, although chronic, can be manageable.

“People have a lot of fears when they’re first diagnosed with diabetes; that they’ll have all of these complications,” she said. “It’s really not the case if you take care of it. I can tell them that I’ve kept my A1C in the range where it needs to be, I am not having any complications. It’s treatable, but it is something you deal with day by day by day. I can understand dealing with a chronic disease that doesn’t go away.”

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