Meet Type 1.5 Diabetes—the Overlooked Condition More Common in People Over 30
Receiving a diabetes diagnosis can be bittersweet. You may feel anxious and scared about what lies ahead and relieved knowing you’ll be connected with the right treatment. But what if the diagnosis isn’t spot on and the treatment doesn’t seem to be helping you in the long term? That’s what can happen for people with type 1.5 diabetes—a form of diabetes that’s sometimes overlooked or misidentified.
Clinically known as latent autoimmune diabetes in adults (LADA), this condition often looks a lot like type 2 diabetes, especially in its earlier stages. But in reality, it’s an autoimmune disease that eventually requires insulin, just like type 1 diabetes.
Because LADA usually appears in adulthood and develops gradually, many people with the condition are misdiagnosed with type 2 diabetes, which is a big problem that can delay the right treatment. Oral medications and lifestyle changes like diet and exercise that are typically prescribed to treat type 2 diabetes may not bring the improvements doctors expect to see, all the while the immune system continues to gradually attack cells in the pancreas that produce insulin. As a result, blood sugar isn’t in control and the body undergoes further harm.
Different types of diabetes require different treatment approaches, so getting the right diagnosis matters. Here’s what you should know about this condition, how it impacts the body, and why a proper diagnosis is so important.
How is LADA different from other types of diabetes?
To understand LADA, it’s helpful to understand how type 1 and type 2 diabetes work.
Type 1 diabetes is an autoimmune condition where the pancreas either makes very little insulin or no insulin because the immune system attacks important cells in the pancreas that produce insulin. Without insulin, blood sugar builds up in the bloodstream, often causing sharp spikes in blood sugar. People with this form of diabetes have to take insulin each day to survive. It can happen at any age, but typically develops in children or young adults.
“It’s an autoimmune condition where you have antibodies that attack the pancreatic beta cells— the cells that make insulin—and they destroy those cells,” Rozalina McCoy, MD, associate division chief for clinical research, Division of Endocrinology, Diabetes, and Nutrition at the University of Maryland School of Medicine tells SELF. “That is what causes insulin deficiency.”
Type 2 diabetes is a chronic condition where the body still produces insulin, but has trouble using it properly—this is known as insulin resistance and causes high blood sugar. “If your insulin doesn’t work as well, the glucose can’t get from the blood into the cells as efficiently, so blood sugar rises,” Dr. McCoy says. “This pathway is what leads to type 2 diabetes.”
Type 2 is way more common than type 1 diabetes and accounts for between 90% and 95% of people with diabetes. Some of the most common risk factors include having overweight, being physically active fewer than three times per week, being 45 or older, or having an immediate family member with the condition. Type 2 diabetes is usually managed with lifestyle changes and oral medications like Metformin that address the underlying insulin resistance, though some people eventually need insulin.
So where does LADA fit in?
LADA is sometimes called type 1.5 diabetes because it shares features of both type 1 and type 2 diabetes. Similar to type 1 diabetes, LADA is an autoimmune condition where your immune system mistakenly attacks important cells in the pancreas that produce insulin. But while type 1 diabetes usually appears suddenly in kids or young adults, LADA develops more gradually and is typically diagnosed in people who are 30 or older.
In the early stages, people with LADA are able to make enough insulin to keep their blood sugar levels somewhat close to a normal range. This is where things can get a bit complicated. Because the body is still producing insulin in the early stages of LADA for at least six months following diagnosis, people with this condition are often misdiagnosed with type 2 diabetes and prescribed oral medications like metformin and lifestyle changes.
That’s a big problem, because when someone has LADA, their body’s ability to produce insulin declines, and over time, those medications stop working.
“They ultimately, at some point, progress to needing insulin, just like type 1,” Dr. McCoy says. “But it happens in adulthood and it's latent, meaning it's slower.”
If someone with LADA is misdiagnosed with type 2 diabetes, they don’t know they need insulin and are instead left taking medications and trying lifestyle changes that don’t actually address the issues going on in their body. This could result in uncontrolled high blood sugar, which can increase the risk for strokes, heart attacks, ketoacidosis (a life-threatening diabetes complication), and other serious issues, Wilson Sze, MD, an endocrinologist at Houston Methodist, tells SELF.
“If you don’t produce enough insulin yourself, having uncontrolled diabetes and having persistently high blood sugars can really cause a lot of issues,” Dr. Sze says.
Usually, LADA is classified as a form of type 1 diabetes.
Because LADA is an autoimmune condition that requires insulin therapy, many physicians actually view it as a subset of type 1 diabetes rather than as a completely separate type of diabetes. Dr. McCoy is among them, explaining that LADA is simply type 1 diabetes in adults that take longer to develop a need for insulin therapy.
“The more we test for this in adults, the more we understand about the fact that type 1 diabetes is a heterogeneous disease—it's not the same in everybody,” Dr. McCoy says. “Across all ages there's variability in how long the period is from getting antibodies to those antibodies destroying the pancreatic cells and developing diabetes.”
A proper diagnosis is key in connecting people with the right treatment.
A type 2 diabetes diagnosis when someone actually has LADA can get in the way of proper treatment. Dr. Sze says that when people are in this scenario, they may go to their doctor saying that they’ve been working hard to do everything their doctor suggested to treat type 2 diabetes—like exercising more, eating a more nutritious diet, and taking prescribed oral medications—but they’re just not seeing results. To him, that’s a sign he should consider screening for LADA. “It's very easy for us to screen for type one or LADA,” he says. “It's just a blood test.”
To diagnose the condition, doctors typically start with fasting blood sugar, A1C, and glucose tolerance tests, all of which measure blood sugar levels and help confirm diabetes or prediabetes. Doctors also need to confirm the autoimmune response, which is evident through the presence of those autoantibodies that attack cells in the pancreas that we mentioned earlier.
Your endocrinologist will likely order blood tests that look for diabetes-related autoantibodies and they’ll also measure C-peptide levels, which indicate how much insulin the body is still making. If test results show low C-peptide levels and the presence of antibodies, there’s a good chance someone has LADA, not type 2 diabetes, Dr. Sze says.
“That's an indication that it's time to think outside the box and switch from oral medications or oral hypoglycemics to insulin therapy,” Dr. Sze says.
Signs to look out for
LADA can be easy to overlook because it develops later than life and often presents with the same signs as type 2 diabetes, including:
- increased thirst
- peeing more than usual
- weight loss seemingly for no reason
- feeling fatigued and tired
- blurry vision
- numbness or tingling in your hands and feet
Dr. Sze and Dr. McCoy also look for some other telling signs: someone with LADA may have a family history of type 1 diabetes, a BMI that’s a bit lower than typically seen in patients with type 2 diabetes, and they may have uncontrolled blood sugar even though they’re working really hard on diet and lifestyle changes and taking oral medication for type 2 diabetes. These signs let the physician know that someone may have an autoimmune condition where the pancreas simply isn’t making enough insulin, Dr. Sze says.
“If somebody's presentation and history aren't consistent with type two diabetes, they should be checked for type one diabetes or LADA, because the treatments are so different,” Dr. McCoy says.
Treatment can help avoid or delay complications.
The exact approach to treating LADA varies depending when someone is diagnosed and how far along they are in the condition’s progression at that point. Your doctor may prescribe oral medication and lifestyle changes like physical activity and healthy eating if the pancreas is still producing insulin. But eventually, as the body’s ability to produce insulin declines, insulin therapy will be needed. The timeline can vary, but sometimes this takes years, Dr. McCoy says.
As the condition progresses, it’s important that your doctor monitors you regularly to determine when treatment with insulin is necessary. “At some point people with LADA will need insulin and we don't want to miss that,” Dr. McCoy adds.