Once used to refer to unexplained glucose fluctuations in certain people, the term is now outdated and is more descriptive in modern diabetes care than defining a form of diabetes.
The term brittle diabetes formerly referred to people with diabetes who had extreme fluctuations in their blood sugar levels and weren’t able to manage the condition effectively.
While once believed to be a distinct form or subtype of diabetes, modern diabetes guidelines do not recognize it as a formal diagnosis or encourage its use. Today, the term is largely considered outdated. Though some still use it informally, it generally refers to those with frequent and severe glucose fluctuations who need more individualized care.
Instead, diabetes healthcare professionals focus on blood sugar management and helping people with diabetes better manage their condition.
Brittle diabetes is also known as labile diabetes, a rare form of the condition where glucose levels dramatically and without explanation go very high and very low despite one’s management.
Historically, the label of “brittle diabetes” first appeared in the pre-glucose meter days of the 1930s and was used to describe patients who regularly had very low blood sugars or diabetic ketoacidosis (DKA).
In the 70s and 80s, it evolved into a non-diagnostic term for any diabetes that was difficult to manage and characterized by extreme and unexplained glucose level swings.
Diabetes care since the advent of fast-acting analog insulins, insulin pumps, and continuous glucose monitors (CGMs) has made the brittle diabetes label largely outdated.
Neither the American Diabetes Association (ADA) nor the World Health Organization (WHO) recognize the term, and the ADA discourages its use. Many diabetes clinicians believe it’s a misnomer that only leads to confusion.
Well-respected members of the diabetes medical community agree that it’s a rare condition, and the term is mostly used incorrectly by both physicians and those with diabetes.
“I’ve mostly seen clinicians coin people ‘brittle’ when they just haven’t had the time, expertise, or inclination to figure out what is causing the ups and downs that some of their patients experience,” said Gary Scheiner, a certified diabetes care and education specialist with T1D himself. “That’s nothing more than a cop-out.”
In the past 20 years, Scheiner notes that more research has surfaced on the sub-classifications of diabetes, and it’s now clearer that many T1Ds still produce a tiny trace of insulin. Some have enough to provide a degree of stability, while others have less insulin and stability, he said.
Dr. George Grunberger, a Michigan endocrinologist who has been practicing for more than 40 years, told Healthline that the term has been mostly discarded in the past 15 years. In all his years of practice, he’s never had a patient with a true brittle diabetes diagnosis.
“In the simplest terms, if you can find a reason for the blood sugar swings, then it’s not brittle diabetes. That’s been a really difficult issue to tackle, because the problem you have is that both physicians and patients used it for so long without really understanding what they’re talking about.”
Dr. Robert Gabbay, former chief medical officer of the Joslin Diabetes Center, echoed his colleagues’ perspective.
He noted that he “rarely, if ever” hears an endo use the word “brittle” these days. He pointed out that primary care professionals mostly use it as a label for people who have difficulty managing their diabetes.
Gabbay doesn’t care for the term, he says, because he feels that it gives primary care physicians an easy excuse “not to delve deeper” when working on difficult cases. “It’s almost like saying, ‘I give up, you have brittle diabetes.'”
Gabbay says most people with difficult-to-manage diabetes can be sorted out and helped, although he does admit that there’s a small percentage who continue to have highly variable glucose levels despite all efforts to the contrary.
“That is a patient with a lot of glucose variability,” he said.
While the term is considered outdated, some clinicians still use it to describe unmanaged diabetes, particularly for those with diabetes who are hospitalized with severe high or low blood sugar levels.
This 2020 research points to those who may be described as having brittle diabetes as fitting into one of 4 general life-stage categories:
- Younger people with diabetes (more commonly females at birth) who may experience mental health issues related to an eating disorder, such as diabulemia.
- People who have another medical condition that affects insulin sensitivity and glucose levels, possibly a nutritional disease that leads to an insulin and glucose mismatch.
- Older adults who have mental and cognitive conditions such as dementia or Alzheimer’s, and are unable to self-manage their diabetes and experience severe glucose level instability.
- People with diabetes who cannot afford or get access to the insulin or diabetes medications and supplies they need to manage their condition.
Other possibilities for these
- mental health disorders
- lipohypertrophy on the skin resulting from repeated insulin injections over time, leading to less insulin absorption and blood sugar fluctuations
- food insecurity
Importantly, the latest research indicates that clinicians no longer commonly use the term “brittle diabetes” in diagnosing a type of diabetes.
The above categories and possible risk factors are more tied to those with T1D who may be less able to effectively manage their condition, even with insulin pump therapy and CGM technology.
While insulin pumps and CGM technology could be ways for those with diabetes to better monitor and manage fluctuating blood sugar levels, there may be alternatives for those with what’s described as “brittle diabetes.”
In 2023, the Food and Drug Administration (FDA) approved Lantidra (donislecel), the first
Islet cell transplantation and encapsulation aren’t new, but they are
The more recently approved therapy is known as donislecel, marketed as Lantidra. It involves a surgical procedure to transplant insulin-producing pancreatic islet cells from deceased organ donors into the pancreas, essentially serving as a sort of “cure” for diabetes.
It’s indicated for T1D treatment in adults, specifically for those unable to approach their target A1C because of “repeated episodes of severe hypoglycemia despite intensive diabetes management and education.”
There are several risks and possible side effects.
People who receive this therapy must take immunosuppression drugs, which can lead to other health and diabetes-related side effects, given their effect on the immune system and body overall.
The procedure is also very expensive, estimated at $300,000 per person, and it may not be covered by insurance because it’s so new and is considered experimental.
Your healthcare team can discuss this option with you if you’re possibly eligible and have experienced unstable glucose levels over time despite diabetes management efforts.
Brittle diabetes, or labile diabetes, is an outdated medical term that isn’t common in modern diabetes care.
Described as someone who has severe fluctuations in blood sugar levels despite their management, brittle diabetes is viewed by most in the diabetes community as a way to describe unstable glucose levels.
Your healthcare team can help develop your diabetes care plan and determine whether medication changes, mental health issues, or other medical conditions may be contributing to blood sugar fluctuations.
Options such as insulin pumps and CGM technology can help improve blood sugar management. If other treatment options aren’t working effectively, other advanced treatments, including islet cell transplantation, may be options in more extreme cases.