Latent Autoimmune Diabetes of Adults - LADA or Diabetes Type 1.5
Most people are familiar with the fact that there two types of diabetes: Diabetes Type 1 and Diabetes Type 2. But there is another sub-type known as "latent autoimmune diabetes of adults" and is loosely termed Diabetes Type 1.5, or sometimes abbreviated as LADA.
Some say that latent autoimmune diabetes of adults may comprise of 10% of the diabetic population, which would make it more common than the traditional Type 1.
Diabetes Type 1 typically occurs in juveniles. Hence it was formally known as "juvenile diabetes". And Type 2 is formerly known as "adult onset" diabetes which occurs later in life when metabolic syndrome and insulin resistance sets in.
Now we know that anybody at any age can develop Type 1 diabetes. And people are developing Type 2 diabetes earlier and earlier including teenagers. Hence the terms "juvenile" and "adult onset" diabetes are being replaced with the usage of the terms "Type 1" and "Type 2" diabetes instead.
However, the term "Latent Autoimmune Diabetes of Adult" refers to those who develop Type 1 type as an adult and have the slower progressing form of Type 1.
Jenny Ruhl writes on her site ...
"Up to 20% of people diagnosed with Type 2 diabetes are not overweight. If you are one of them, it's worth doing some research to make sure that you don't, in fact, have one of the forms of what are often called "Type 1.5" diabetes, forms of diabetes that many doctors do not know about."
Type 1 Diabetes and Type 2 Diabetes
The pathology of the Type 1 and Type 2 diabetes are quite different. Type 1 diabetes is an autoimmune disease where the immune system misbehaves and attacks insulin or the beta cells of the pancreas, which are responsible for producing insulin. Insulin is an hormone that allows the glucose fuel from the bloodstream to enter into the cells for energy.
It is needed for our body to store fat and build muscles. It is needed for the body to survive. Prior to discovery of insulin injections in 1920's, people with Type 1 diabetes would die due to the lack of insulin. Dr. Frederick Banting and John Macleod was awarded the Nobel Prize for the therapeutic use of insulin. You can read how insulin was discovered on NobelPrize.org
Type 2 diabetes is different in that it is not an autoimmune disease. Consuming too much sugar or too much calories for the body's need causes the cells to no longer listen to the command of insulin to let glucose fuel in. This is known as insulin resistant and is part of the metabolic syndrome. In Type 2, the body is able to produce insulin and may even produce a lot of it. But the cells are not responding the effects of insulin. Often insulin resistance is characterized by abdominal fat.
In both cases, the lack of insulin of Type 1 and the insulin resistance of Type 2 results in high blood sugar since the sugar (glucose) fuel is not able to enter into the cells and is left stranded in the bloodstream.
Anne Angelone writes that ...
"Some individuals are at a healthy body weight, exercise regularly, and eat a healthy diet yet can’t seem to control their consistently high blood sugar levels. With type 1.5 diabetes an autoimmune reaction destroys cells of the pancreas, but the pancreas still secretes insulin—autoimmune damage is not advanced enough to shut down insulin function." [reference]
How is Diabetes Diagnosed
The official criteria for diagnosing diabetes are listed on the WebMD linked here. Most commonly, the fasting blood sugar blood test or the hemoglobin A1C are used.
Because our blood sugar depends on when and what type of food you have just eaten, the fasting blood sugar test is done at least after eight or ten hours without food.
The hemoglobin A1C test measures what percentage of your red blood cell has been glycated, or damaged by sugars. Glycated means that sugar has stuck onto the red blood cells. Sometime this test is called the Glycohemoglobin A1c test. We don't want sugars sticking to our red blood cells. So 6.5% or higher percentage of glycated red blood cells indicates diabetes. And 5.7 to 6.4% is pre-diabetic.
Whereas the fasting blood glucose tests indicates the blood glucose at the day of the blood draw which can be affected by stress level and other variable factors; the Hemoglobin A1C test indicates the average blood sugar level of the last 2 to 3 months. However, the hemoglobin A1C test results can also be affected by whether your blood cells are long-lived or short-lived.
Other tests that may provide useful information as to your glucose control are ...
- Random Blood Sugar test where several random measurements are made without regards to when you have eaten. Since healthy individuals' blood glucose do not vary widely throughout the day, wide variance can indicate a problem.
- Two-hour postprandial blood sugar measures your blood sugar two hours after a meal.
- Oral glucose tolerance test is a series of measurement of your blood sugar after you drink a glucose solution. Some say this test is very accurate as it is affected by the macro-nutrient composition of your meals a day or two prior to the test.
Chris Kresser also mentions that it is important to know how many hours in the day the blood sugar is above the damaging level of 140 mg/dl (7.7 mmol/L). [reference]
How do you know if it is latent autoimmune diabetes of adult?
Classifying the diabetes as type 1 or type 2 or latent autoimmune diabetes of adult (LADA) is more complicated. Typically type 2 diabetes are obese with abdominal fat and have metabolic syndrome with insulin resistance. Typically type 1 diabetics and LADA are typically thin and slender. However, there are LADA diabetics that are overweight. And LADA can also be somewhat insulin resistant like Type 2. Quite often LADA diabetics are labelled incorrectly as Type 2 simply due to their adult age of diagnosis.
In both Type 1 and LADA, the immune system is attacking the beta cells of the pancreas. The speed of destruction is faster in Type 1 and slower in LADA. Type 1 has a rapid progression to insulin dependence in terms of days or weeks. Whereas LADA takes months or years.
A blog article writes ...
"In young Type 1s a person can go from normal to completely whacked in a week. People with LADA may take up to a decade to lose all their insulin-secreting capacity."
The common way to determine if it is LADA or Type 2, is the diabetes-related antibodies tests which includes Islet Cell Cytoplasmic Autoantibodies (ICA), Glutamic Acid Decarboxylase Autoantibodies (GADA), Insulinoma-Associated-2 Autoantibodies (1A-2A), and Insulin Autoantibodies (IAA).
Presence of immune antibodies indicates latent autoimmune diabetes of adult or type 1. Type 2 does not have these antibodies.
The insulin C-peptide test can measure the amount of insulin secretion and hence an indication of residual beta cell function. C-peptide is typically low with LADA, but higher or normal in Type 2.
Diabetes Forecast has a chart of the three types of diabetes.
There is a good article showing the biomarker comparison of the different types of diabetes. It writes that LADA is ...
"characterized predominantly by adult age at onset (30–40 years), nonobese body type, and initial response to OHA gradually leading to insulin dependency, characteristically low C-peptide levels, and marked presence of GAD autoantibodies. "
And is more frequent in males than in females.
Symptoms of Latent Autoimmune Diabetes of Adults
The symptoms of Latent Autoimmune Diabetes of Adults is the same as for Type 1 diabetes.
Diabetes results in high blood sugar. In the long term, the high blood sugar can cause damage to virtually all organs which comes in contact with the blood supply as the excessive sugar will glycate with the proteins in our organs.
The Type 1 and LADA diabetic condition manifests itself with symptoms such as are frequent urination, increased thirst, increased hunger, and weight loss.
Since the body wants to get rid of that damaging sugar in our bloodstream, there is increased thirst to cause us to drink a lot of water. It tries to expel the sugar via our urine resulting in frequent urination. This diuretic action may cause the body to lose nutrients.
Since there is a lack of insulin, our cells are not getting the glucose fuel energy. Hence there may be increased hunger and large appetite. Weight may decrease as the body can not fuel itself. Furthermore, the body may cannibalize itself by stealing protein from the muscles and converting it to sugar for energy.
Causes of latent autoimmune diabetes of adults
As with all autoimmune diseases, there is a genetic predisposition as well is an environmental triggers for Type 1 and latent autoimmune diabetes of adults. While some believe that LADA is a separate sub-type of diabetes, other believe that LADA is just a mild form of Type 1.
We know that in both LADA and Type 1, the immune system is attacking the pancreas. But why that is the case is unclear.
One unproven theories is that the immune system attacking the casein protein of cow's milk mistakenly attacks the beta cells due to its close molecular similarity.
Some are classifying LADA as being closer to Type 1 as opposed to Type 2. All types of diabetes (including LADA) are increasing. SFGate has article on the rise of Type 1 in adults. We know that Type 2 diabetes is increasing with the increase in obesity. But why are Type 1 and LADA increasing as well. Scientific American calls it a diabetes mystery and list several suspects include gluten, hygiene hypothesis, and infections.
Treatment for Latent Autoimmune Diabetes of Adults
When diagnosed early, LADA may not require insulin injection because the pancreas can still produce some insulin. However, they may reach the point of requiring insulin injection faster than Type 2.
Some estimates that people with LADA may need insulin injections (or an insulin pump) around three to 12 years after diagnoses. Other say an average of 4 years. And others say within 6 years. The amount of time may depend on the amount of antibodies present.
Early management of LADA is to eat a diet low in refined carbs / sugars and regular exercise. But for those with diabetic neurophathy, one has to be careful not to over-exert too strenuously as blood vessels are more fragile. Because exercise can reduces blood sugar, insulin-dependent individuals need to monitor their glucose careful and may need to reduce insulin dosage. Check with your doctor first.
Refined carbohydrates and sugar simulates insulin production the most. If you want to preserve your beta cells, don't ask it to pump out a huge dose of insulin to "cover" the carbohydrates just eaten. Carbohydrates raises blood sugar abruptly. Limiting them will reduce blood sugar spikes.
This means eating mainly non-starchy vegetables and some lean protein and healthy fats. There is a big different between refined carbohydrates and non-starchy vegetables. Check the glycemic index of foods to see which ones raises blood sugar faster. Eat low glycemic index foods. Non-starchy vegetables as they are low in the glycemic index; so eat a lot of those. Refined carbohydrates and sugar such as cookies, bread, flour, and sodas are to be avoided.
Exercise will improve insulin sensitivity. Hence, your cells will respond to insulin better and not as much insulin is needed to provide the same results.
Some clinician may prescribe Metformin which suppresses glucose production by the liver, or they may prescribe Sulfonylurea which attempts to increase insulin production. Because these drugs may have side effects and increased risk of metabolic disorders, other clinicians believe that people with LADA should skip these dangerous drugs and proceed with insulin injection instead.
There is evidence that early treatment with insulin may help preserver whatever insulin producing cells are remaining.
Diabetes Forecast article writes ...
"For people with LADA, there is already some evidence that early insulin treatment may keep beta cells in the business of producing insulin, at least for a while"
Opinions of treatment methodology vary and obvious will depend on the specific circumstance of your case. You should do your own research and consult with your medical practitioner.
If insulin is not "dosed correctly", there is a risk of hypoglycemia which can result in lost of consciousness and be life-threatening. Anyone injecting insulin should carry a glucagon kit, fast-acting food sugars, and medical identification. And family members should know how to use these in the event that the diabetic can not do it themselves.
There is also a risk of hyperglycemia, which left untreated, can lead to a deadly state called diabetic keto-acidosis. Urine test strip can be used to check urine for ketones.
Article was written in December 2012 and is only opinion at the time of writing. Author is not a medical professional and this is not medical advice. Please consult with medical professional as appropriate.