Brittle Diabetes

Brittle diabetes is a term healthcare providers may use to describe diabetes that’s especially difficult to manage. It causes severe swings in blood sugar levels that often result in hospitalizations. Brittle diabetes has several possible causes, and its treatment largely depends on the cause.


What is brittle diabetes?

Brittle diabetes is diabetes that’s especially difficult to manage and often disrupts your everyday life. People with brittle diabetes have severe swings in glucose (sugar) levels. The swings can cause frequent episodes of low blood sugar (hypoglycemia) and/or high blood sugar (hyperglycemia). These episodes may result in frequent hospitalizations.

Brittle diabetes isn’t an official medical diagnosis — it’s just a way to describe difficult-to-manage diabetes. Healthcare providers may also call it labile diabetes or unstable diabetes.

Brittle diabetes mainly affects people with Type 1 diabetes. But it can affect those with insulin-dependent Type 2 diabetes as well. Brittle diabetes often happens due to other physical and/or mental health conditions.


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Symptoms and Causes

What causes brittle diabetes?

There are several possible causes of brittle diabetes. This is because several factors can affect your blood sugar — blood sugar management is a complex process. Many people with diabetes learn to predict some of these impacts with time and practice. But in the case of brittle diabetes, these issues are often difficult or impossible to predict, leading to glucose swings.

In general, the four categories of brittle diabetes causes include:

  • Coexisting physical health conditions.
  • Coexisting mental health conditions.
  • Aging and memory loss.
  • Lack of access to insulin and food insecurity.

Physical conditions that can cause brittle diabetes

Physical conditions that can lead to frequent episodes of high blood sugar include:

These conditions typically cause insulin resistance, which raises blood sugar levels.

Physical conditions that can lead to frequent low blood sugar episodes include:

Certain medications, like long-term use of corticosteroids, can also lead to brittle diabetes.

Mental health conditions that can cause brittle diabetes

A variety of mental health conditions can lead to brittle diabetes for different reasons. Examples include:

Aging and brittle diabetes

Aging and issues with memory (like mild cognitive impairment or dementia) can negatively affect your ability to self-manage diabetes. You may be more likely to:

These issues can lead to frequent high and/or low blood sugar episodes.

Lack of access to insulin and food insecurity

A lack of insulin access — typically due to high costs — can lead to rationing insulin. This frequently leads to diabetes-related ketoacidosis (DKA) and even death.

Food insecurity also often leads to blood sugar instability. Food insecurity refers to the uncertain or limited access to adequate and safe foods. It’s associated with higher A1C levels in both people with Type 1 and Type 2 diabetes.

What are the symptoms of brittle diabetes?

People with brittle diabetes experience sudden and frequent changes in glucose levels. The swings lead to frequent low blood sugar and/or high blood sugar.

Symptoms of low blood sugar

Symptoms of low blood sugar include:

  • Shaking or trembling.
  • Weakness.
  • Sweating and chills.
  • Extreme hunger (polyphagia).
  • Faster heart rate.
  • Dizziness or lightheadedness.
  • Confusion or trouble concentrating.
  • Anxiety or irritability.
  • Tingling or numbness in your lips, tongue or cheeks.

Signs of severe low blood sugar include:

Symptoms of high blood sugar

Early symptoms of high blood sugar include:

Symptoms of long-term high blood sugar include:


What are the complications of brittle diabetes?

Long-term and/or severe episodes of low or high blood sugar that people experience with brittle diabetes can lead to certain complications.

Low blood sugar complications

If you have frequent low blood sugar (hypoglycemia) episodes, you’re at risk of developing hypoglycemia unawareness. This happens when you don’t experience symptoms of low blood sugar because your body is used to having low blood sugar.

If you have hypoglycemia unawareness, you’re more likely to have severe episodes and need medical help. Severe hypoglycemia is life-threatening. In rare cases, it can result in a coma and/or death if it isn’t treated.

High blood sugar complications

Untreated high blood sugar can lead to diabetes-related ketoacidosis (DKA), an acute (sudden and severe) complication of diabetes. Symptoms include:

DKA is life-threatening and requires immediate medical attention.

Frequent high blood sugar episodes over time also increase your risk for diabetes complications, like:

Diagnosis and Tests

How is brittle diabetes diagnosed?

Brittle diabetes isn’t an official medical diagnosis, so there isn’t a formal diagnosis process. Your healthcare provider’s main concern will be finding the underlying cause of frequent glucose level swings.

To do this, your healthcare provider may ask you several questions about your diabetes management. They’ll thoroughly analyze the trends in your glucose levels. They’ll also do a physical exam and may recommend certain tests, like blood tests, imaging tests and psychological evaluations.


Management and Treatment

How is brittle diabetes treated?

The treatment for brittle diabetes largely depends on the underlying cause. For example, treating celiac disease with a strict gluten-free eating plan can resolve frequent low blood sugar episodes. Treating thyrotoxicosis with medication or thyroid surgery can resolve frequent high blood sugar episodes.

Other causes, like gastroparesis, substance use disorders and dementia, for example, may be more difficult to treat or manage.

In general, your healthcare provider may recommend the following strategies to better manage brittle diabetes:

  • Using a continuous glucose monitoring (CGM) device that can alert you when you have high or low glucose levels.
  • Doing more frequent manual blood sugar checks.
  • Having a service dog (called a diabetes alert dog) that’s specially trained to alert you when you have low and high blood sugar.
  • Seeing a mental health professional, like a psychologist, to help you manage mental health concerns that affect diabetes management.
  • Relying on loved ones or at-home nurse aides to help you manage your diabetes.
  • Working with a social worker to find solutions to a lack of insulin access and food insecurity.
  • Using an insulin pump for more precise insulin dosing and adjustments.

In severe cases of brittle diabetes in which the underlying cause isn’t manageable, you may be eligible to receive a pancreas transplant. This typically allows you to no longer have diabetes.


Can I prevent brittle diabetes?

Brittle diabetes isn’t always preventable. But one of the best things you can do to try to prevent it is to see your healthcare providers regularly, including your endocrinologist and primary care physician (PCP). This allows you to stay up to date on your diabetes management — which will change over time — and your overall health.

Outlook / Prognosis

What is the outlook for brittle diabetes?

Brittle diabetes often leads to frequent hospitalizations for severe low blood sugar and/or DKA. It can also result in:

  • Low quality of life.
  • Long-term diabetes complications.
  • Issues maintaining employment.
  • Strain on relationships.
  • Issues with becoming pregnant or maintaining a pregnancy.

If you have brittle diabetes, it’s crucial to see your healthcare provider regularly to figure out strategies to best manage your blood sugar levels. With proper treatment, diabetes technology and support, many cases of brittle diabetes are manageable.

What is the life expectancy for someone with brittle diabetes?

There are many possible causes and severity levels of brittle diabetes. So researchers don’t know how much brittle diabetes affects life expectancy. But because it’s associated with an increased likelihood of long-term diabetes complications, it may lower your life expectancy. In addition, left untreated, severe low blood sugar and DKA are fatal. It’s important to get care right away if you have these conditions.

Living With

When should I see my healthcare provider if I have brittle diabetes?

It’s crucial to see your healthcare providers regularly if you have brittle diabetes, especially if you have a chronic coexisting condition that’s causing the blood sugar swings. If you notice significant changes in your blood sugar levels, see your provider.

When should I go to the ER?

If you have signs of DKA, go to the nearest emergency room. If you have severe low blood sugar, call 911 or your local emergency service number.

A note from Cleveland Clinic

Brittle diabetes happens when other conditions or situations make diabetes extra challenging to manage. Having brittle diabetes isn’t your fault. But there are steps you can take to better manage it, like seeing your healthcare provider regularly and following your diabetes management plan closely. You’ll likely need to lean on loved ones for support, too.

Medically Reviewed

Last reviewed on 02/06/2024.

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