Could Your Prediabetes Actually Be Type 1 Diabetes?
A diagnosis of prediabetes typically sets off a familiar course of action with your doctor: weight loss, exercise, and lifestyle changes to prevent the progression to type 2 diabetes. But what if there’s more to the story? According to Shore Physicians Group Endocrinologist Dr. Matthew Corcoran, some cases of prediabetes may actually be early stages of type 1 diabetes, an autoimmune condition that requires entirely different management.
This distinction matters more than ever because, for the first time, there’s a therapy available that can delay the progression of type 1 diabetes. Identifying the correct diagnosis early through screening is critical for ensuring patients receive appropriate care and can potentially benefit from this groundbreaking treatment. If you’ve been diagnosed with prediabetes, it’s important to have a discussion with your doctor to see if you should be screened for type 1 diabetes.
Type 1 vs. Type 2 Diabetes: Why It’s Not Always Obvious
One of the biggest challenges in adult endocrinology is that type 1 diabetes often seems to masquerade as type 2 diabetes. In fact, Dr. Corcoran sees about 25-30 patients a year who have been treated for type 2 and aren’t responding, only to discover they actually have type 1.
“Type 1 diabetes is often thought of as a disease diagnosed primarily in children, but about 30% of people with type 1 are diagnosed after the age of 25,” says Dr. Corcoran. “Adults with type 1 progress more slowly than children, so they don’t always present with the dramatic symptoms we associate with the disease,” Dr. Corcoran explains. “They may still make some insulin for years, which can mask the true diagnosis.”
There are red flags that can help primary care doctors and patients diagnosed with prediabetes or type 2 diabetes identify when it’s time to dig deeper:
- Family History: Having a first-degree relative (parent, sibling, or child) with type 1 diabetes increases your risk 15-fold.
- Other Autoimmune Conditions: Conditions like thyroid disease, rheumatoid arthritis, or celiac disease can raise the likelihood of type 1 diabetes.
- Lack of Response to Treatment: Patients who aren’t responding well to standard treatments for type 2 diabetes should consider further evaluation.
The Role of Antibody Testing
The key to identifying early type 1 diabetes lies in a simple blood test for specific antibodies. These antibodies indicate an autoimmune attack on the pancreas, which is characteristic of type 1 diabetes.
“I screen patients for type 1 about 5 to 10 times a week, and most are antibody negative, but about 5-10 percent are positive for at least one antibody. That’s when they need the help of an endocrinologist,” Dr. Corcoran says.
Type 1 diabetes usually presents in the following three stages, and the first two typically don’t have any symptoms.
- Stage 1: Antibody-positive, with normal glucose levels.
- Stage 2: Antibody-positive with an A1C between 5.7 – 6.4%, and fasting glucose of 100 to 125.
- Stage 3: Symptomatic type 1 diabetes requiring insulin, with a fasting glucose over 125 or hemoglobin A1C greater than 6.5%. (Currently, these patients are not a candidate for the new therapeutic.)
“By identifying type 1 early, we can help delay progression to stage 3 with a new immunotherapy that can delay type 1 diabetes onset by two years or more.”
What This Means for Patients and Providers
For patients, this highlights the importance of being aware of the possibility it could be type 1 and asking your doctor the right questions:
- “Is my prediabetes definitely type 2, or could it be early-stage type 1?”
- “Should I be tested for antibodies, especially given my family history or other autoimmune conditions?”
For primary care providers, it’s a call to action to include antibody testing when prediabetes or diabetes presents alongside risk factors like family history, autoimmune conditions or lack of response to treatment.
Dr. Corcoran emphasizes the importance of collaboration between primary care and endocrinology. “If we catch these cases early, we can prevent mismanagement and ensure patients are on the right treatment path.”
If you or a loved one have been diagnosed with prediabetes or type 2 diabetes and you have risk factors for type 1 diabetes, talk to your doctor about antibody testing. It’s a small step that could make a big difference.
Dr. Matthew Corcoran is an endocrinologist with Shore Physicians Group’s Division of Endocrinology, located at 18 W. New York Ave., Somers Point, NJ. Board-certified in Endocrinology, Diabetes, and Metabolism, he trained at Georgetown University School of Medicine and the University of Chicago hospitals. A leading expert in diabetes and exercise, Dr. Corcoran founded Diabetes Training Camp, a nonprofit focused on empowering individuals with type 1 diabetes through fitness and education. He has been recognized as a “Game Changer” by the American Diabetes Association and named a “Top Doctor” by Philadelphia Magazine from 2019–2021. To learn more about Dr. Corcoran and schedule an appointment, click here.
