What Is Latent Autoimmune Diabetes in Adults (LADA)?

Latent autoimmune diabetes in adults (LADA) is an autoimmune condition affecting insulin function similar to type 1 diabetes, with the major difference being that LADA sets in during adulthood, usually after age 30. Also called type 1.5 diabetes, LADA is often initially misdiagnosed as type 2, as symptoms may be similar. If you're following an active lifestyle, in a healthy weight range for your body, and have been diagnosed with type 2 diabetes, it is possible you could actually have LADA. In fact, LADA may account for up to 10% of cases of diabetes, regardless of type.

While LADA may at first be managed through lifestyle changes such as diet and exercise, the condition will eventually require insulin therapy, though insulin may not be required for months or even years after your initial diagnosis. LADA is a lifelong condition and isn't reversible, as is generally the case for type 2 diabetes.

LADA Symptoms

LADA can strike later in life than typical type 1 diabetes. Symptoms may be quite vague, but usually mimic those of both type 1 and type 2 and include the following:

• Increased thirst and dry mouth, even with regular fluid intake
• Frequent urination
• Extreme fatigue
• Unexplained weight loss
• Extreme hunger
• Blurry vision
• Tingling nerves

Symptoms of LADA may come on rather slowly, throughout the course of several months, as opposed to symptoms of type 1, which can appear suddenly. In contrast, symptoms of type 2 diabetes also come on slowly. There are further crossovers between the symptoms of the three types:

Complications

Although at initial presentation patients with LADA may appear to have more beta-cell function in the pancreas than in those with type 1, this can rapidly decline, requiring quick intervention via insulin injections. If left untreated, blood glucose levels may soar too high in the absence of adequate insulin. As a result, the body will start to break down fat for fuel as no glucose can get into the cells—a dangerous condition called diabetic ketoacidosis.

Just as with type 1 and type 2 diabetes, other complications may arise with LADA beyond ketoacidosis, including: 

• Diabetic retinopathy
• Diabetic neuropathy
• Diabetic nephropathy
• Cardiovascular complications, such as stroke and acute coronary events

Causes

To understand the causes of LADA, it can be helpful to distinguish between the various types of diabetes.

Type 1 diabetes is an autoimmune condition, in which the body mistakenly views its own cells as foreign, in this case, the beta cells of the pancreas, which are responsible for producing insulin. As a result, insulin production shuts down and the body must rely on an external source of insulin to remove glucose from the bloodstream, usually in the form of insulin injections.

Type 2 diabetes is marked by the body's increasing resistance to the effects of insulin. Type 2 diabetes is considered a lifestyle disease, which are preventable chronic diseases that often arise as a result of lifestyle factors such as obesity, a diet rich in simple carbohydrates, and inactivity.

LADA, or type 1.5 diabetes, is primarily categorized as an autoimmune condition, though it may also be marked by varying degrees of insulin resistance, linking its origins to type 2 diabetes as well.

The autoimmune origins of LADA are still unknown, researchers have correlated the following factors in most cases of LADA:

• A family history of autoimmune conditions
• A genetic predisposition to type 1 or type 2 diabetes

Thyroid disease is also common comorbidity with LADA, meaning that the two conditions often coexist, though it is not known if one causes the other.

Diagnosis

Because LADA occurs in adults, it is often initially diagnosed as type 2 diabetes. Diagnosing patients with LADA can still be fairly tricky and may take time, and type 1.5 diabetes is still not officially recognized by all practitioners. Patients diagnosed with LADA tend to exhibit the following conditions:

• Over the age of 30
• Less likely to be overweight, with a BMI below 25 and a low waist-to-hip ratio
• The presence of antibodies such as glutamic acid decarboxylase 65 (GAD) antibody and/or others
• The presence of a low-to-normal C-peptide count (a substance made along with insulin in the pancreas that can show how much insulin your body makes)

Lab Testing

The following lab tests may be useful for diagnosis of LADA:

• Fasting plasma glucose test: A blood test occurring after you've fasted for eight hours
• Oral glucose tolerance test: A blood test occurring after you've fasted for eight hours and two hours after you've consumed a glucose drink
• Random glucose tolerance test: A blood test that looks at glucose levels without fasting
• C-peptide test
• GAD antibody and other LADA-specific antibody testing

Treatment

Type 1.5 diabetes is usually a lifelong condition. The goal of treatment is to support the body's natural insulin production for as long as possible.

At first, LADA may be best managed by lifestyle changes such as diet and exercise to help control your body's glucose levels, but as your insulin production declines, you may need to take insulin shots. The timeline for insulin support varies with each individual but usually occurs within five years of diagnosis.

Treatment methods also include taking oral diabetes medications to help control blood sugar and using medication to support your current insulin output. Work with an endocrinologist to create a customized plan that works for you.

A Word From Verywell

You may feel isolated, confused, frustrated, and/or in shock or denial about your LADA diagnosis, but know that you're not alone. Seek out a support group in your area or online for others diagnosed with LADA. While there is no current cure, there are numerous advances in insulin therapies and monitoring devices that can fit into your everyday lifestyle and make the disease more manageable.

While it can be overwhelming, a LADA diagnosis is not a death sentence. Surround yourself with supportive care providers, such as an endocrinologist and certified diabetes educator, who can both help create a management plan that works for you. Aim to keep stress to a minimum and practice good self-care. With time, you'll get to know your disease and how to care for yourself.