ConditionHormones & metabolism
Latent Autoimmune Diabetes in Adults (LADA)
Latent autoimmune diabetes in adults (LADA), sometimes called type 1.5 diabetes, is a slow-developing form of autoimmune diabetes that starts in adulthood, usually after age 30. Like type 1 diabetes, the immune system attacks the insulin-making cells of the pancreas, but much more gradually, so people often manage without insulin for months or years and are first diagnosed with type 2. Positive diabetes antibodies confirm it. Most people with LADA eventually need insulin.
Also called: LADA, type 1.5 diabetes, slow-onset type 1 diabetes, latent autoimmune diabetes
At a glance
- What it is
- Autoimmune diabetes that develops slowly in adults.
- How common
- Thought to make up roughly 2 to 12 in 100 adults diagnosed with diabetes, varying by population.
- Clues
- Diagnosis after 30, normal or low body weight, poor response to tablets, other autoimmune conditions.
- Diagnosis
- Diabetes antibodies (especially GAD) and C-peptide to measure remaining insulin production.
- Treatment
- Lifestyle measures, certain tablets early on, and insulin as production falls.
When to get help
Call 911 or go to the ER
- Vomiting, belly pain, deep or fast breathing, fruity-smelling breath, confusion or extreme drowsiness, especially with high blood sugar (possible diabetic ketoacidosis)
- Blood sugar below 54 mg/dL (3.0 mmol/L) with confusion, or any severe low that needs someone else's help
See a doctor within a day or two
- Blood sugar staying above 300 mg/dL (16.7 mmol/L), or ketones in blood or urine
- Rapid weight loss, intense thirst and frequent urination despite diabetes tablets
Book a routine appointment
- Diabetes diagnosed after age 30 with a normal weight, or with type 1 diabetes or autoimmune disease in the family
- Blood sugar control worsening within months to a few years of diagnosis despite treatment
- Thyroid symptoms, gut symptoms, or vitamin B12 deficiency alongside diabetes (other autoimmune conditions)
What makes LADA different
| Type 1 diabetes | LADA | Type 2 diabetes | |
|---|---|---|---|
| Typical age at onset | Childhood to young adult, can be any age | Usually over 30 | Usually over 40 |
| Cause | Autoimmune destruction of beta cells, fast | Autoimmune destruction, slow | Insulin resistance with gradual beta-cell decline |
| Diabetes antibodies | Usually positive | Positive (often GAD) | Negative |
| Body weight | Usually normal | Often normal, can be overweight | Often overweight |
| Insulin at diagnosis | Needed | Usually not needed for at least 6 months | Not usually needed |
| Response to tablets | Poor | Good at first, then declines | Good for years |
| Ketoacidosis risk | High | Increases over time | Low |
LADA shares genetic and immune features with type 1 diabetes and some metabolic features with type 2 diabetes. Many experts now consider it a slower form of type 1 diabetes.
Symptoms
Symptoms develop gradually and are the same as other forms of diabetes:
- increased thirst and frequent urination
- tiredness
- blurred vision
- unintended weight loss
- slow-healing cuts and frequent infections
Some people have no symptoms and are diagnosed on a routine blood test.
Who might have LADA
Doctors consider testing for LADA when an adult with diabetes:
- is not overweight, or is younger at diagnosis
- has a personal or family history of autoimmune disease, such as Hashimoto's thyroiditis, celiac disease, vitiligo or type 1 diabetes
- loses weight unintentionally
- has blood sugar that rises quickly despite metformin or other tablets
- needs insulin within a few years of diagnosis
- lacks typical features of metabolic syndrome, such as high blood pressure and abnormal cholesterol
Diagnosis
LADA is usually defined by three features:
- Adult onset, typically after age 30
- Positive diabetes autoantibodies, most often to glutamic acid decarboxylase (GAD). Other antibodies (IA-2, ZnT8, islet cell antibodies) may also be tested
- No need for insulin for at least 6 months after diagnosis
C-peptide, measured in the blood, shows how much insulin the pancreas is still making. Low C-peptide predicts a sooner need for insulin and guides treatment. Higher antibody levels also predict faster progression.
Treatment
Treatment aims to control blood sugar, protect remaining insulin-producing cells, and prevent complications. An international expert consensus suggests tailoring treatment to C-peptide levels.
Higher C-peptide (more insulin production left)
- healthy eating, physical activity and weight management
- metformin
- medicines such as DPP-4 inhibitors, GLP-1 receptor agonists, or pioglitazone, which may help preserve beta-cell function
- SGLT2 inhibitors with caution, because of a higher risk of ketoacidosis as insulin production falls
- sulfonylureas are generally avoided, as they may speed up beta-cell loss
- insulin can be started early in some people
Low C-peptide
- insulin therapy, usually basal-bolus as in type 1 diabetes, often with continuous glucose monitoring
Monitoring
- HbA1c every 3 to 6 months
- C-peptide checks to track decline
- screening for thyroid disease, celiac disease and B12 deficiency
- routine diabetes care: eyes, kidneys, feet, blood pressure and cholesterol
Outlook
Most people with LADA eventually need insulin, often within 5 to 10 years, sometimes sooner. With good glucose control and regular screening, people with LADA can avoid complications as effectively as those with other types of diabetes. Being correctly diagnosed matters, because it avoids months or years of poor control on ineffective tablets and lowers the risk of diabetic ketoacidosis.
Frequently asked questions
What is LADA diabetes?
LADA is latent autoimmune diabetes in adults. It is an autoimmune form of diabetes, like type 1, that develops slowly in adults. Many people are first told they have type 2 diabetes, but antibody tests show the immune system is attacking the pancreas.
How is LADA different from type 2 diabetes?
LADA is caused by an autoimmune attack on insulin-producing cells, while type 2 diabetes mainly involves insulin resistance. People with LADA have positive diabetes antibodies, are often not overweight, and usually need insulin sooner than people with type 2.
How do you test for LADA?
A blood test for diabetes antibodies, especially GAD antibodies, confirms LADA. A C-peptide test measures how much insulin your body still makes, which helps decide whether and when insulin is needed.
Will I need insulin if I have LADA?
Most people with LADA eventually need insulin, often within several years of diagnosis. Some can manage for a while with lifestyle changes and certain tablets, but insulin should not be delayed once blood sugar control declines.
Why is it called type 1.5 diabetes?
It has features of both types. Like type 1, it is autoimmune and antibodies are present. Like type 2, it appears in adults and initially responds to tablets. "Type 1.5" is an informal name. The medical term is latent autoimmune diabetes in adults.
Sources
This guide was written from current patient and clinical guidance, including:
- American Diabetes Association: Standards of care in diabetes, classification and diagnosis
- International expert panel consensus: Management of latent autoimmune diabetes in adults (Diabetes, 2020)
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK): What is diabetes
- Diabetes UK: Latent autoimmune diabetes in adults
- MedlinePlus (US National Library of Medicine): Type 1 diabetes