Once, there were two types of diabetes. Most are familiar with type 1, formerly known as juvenile diabetes; and with type 2, which until recently generally only occurred in adults. However, a Norman man is getting a real life lesson about a form of diabetes that is neither type 1 nor type 2, but instead a little of both.
It's called Latent Autoimmune Diabetes in Adults or LADA. People with LADA show signs of both type 1 and type 2 diabetes, and it is often misdiagnosed as type 2.
Nathan Mobley, 35, of Norman doesn't look like the typical adult who might get diabetes. Quite thin and very health conscious, he first attributed his constant thirst and frequent urination to the dry weather.
"Also, I was feeling really tired a lot," said Mobley, "even though I was making a point of getting more sleep. I was so tired that I was taking naps during the weekend."
When the symptoms persisted, he decided to see his doctor.
"My general practitioner, at first, thought it was type 2. I think because of my age, but then later thought it might be type 1. Even then, though, he wasn't sure. So he referred me to the Harold Hamm Diabetes Center," Mobley said.
Dr. James Lane, an endocrinologist with the Harold Hamm Diabetes Center at the University of Oklahoma, ordered blood tests to measure both autoantibodies and insulin production. The results were convincing. Mobley had, not type 1 or type 2 diabetes, but instead type 1.5 - LADA.
Some believe LADA is actually a slower developing form of type 1 diabetes because patients like Mobley have the same antibodies that target and destroy the insulin-producing beta cells of the pancreas.
"Most people with LADA still produce their own insulin when first diagnosed, like those with type 2 diabetes. However, as LADA progresses, the beta cells of the patient's pancreas may no longer make insulin because their own immune system has destroyed them as in type 1 diabetes," said Lane.
In the early stages, patients with LADA do not typically require insulin. Instead, they control their blood glucose (sugar) levels with meal planning, physical activity and oral diabetes medication.
"I was always careful to make sure I didn't get too much sugar, didn't eat candy or sweets or drink soda. But now, I am much more aware of my overall nutrition – carbs, fats and protein," Mobley said. "Also, I was always pretty active, but now I do more focused exercise."
In addition, Mobley takes the oral medication metformin. The decision to take medication was not easy for Mobley because of his religious beliefs. He didn't even like to take pain medication, but he has learned that because of LADA, his body can't do it alone. He now uses the oral medication only when absolutely necessary.
Lane said that for most with LADA, insulin generally becomes essential to control blood glucose levels. Usually, this is several years after diagnosis.
Interestingly, the National Institute of Diabetes and Digestive and Kidney Diseases reports researchers estimate that as many as 10 percent of people diagnosed with type 2 diabetes have LADA. However, it may not be necessary to test all individuals with type 2 diabetes for LADA.
"It really depends upon each patient," Lane said. "For instance, it may not make sense to test in an extremely obese individual because the treatment for LADA would be much the same as the treatment for type 2 diabetes. However, in someone who is very lean and physically active like Mr. Mobley, the testing can help us better tailor treatment."
A 2008 Japanese study found that early treatment with insulin for patients with LADA may help them avoid total dependence on insulin longer better than oral medications. Mobley hopes to delay taking insulin as long as possible.
"Apparently, there will be a day when my insulin production cells have all been destroyed and I will have to take artificial insulin, but I am waiting as long as I can," he said.
The NIDDK points out another possible benefit to testing all patients for LADA is that medicines that are currently being developed to prevent or cure type 1 diabetes may also be effective against LADA.
"The ultimate goal would be to have a medication that would alter the underlying disease process," Lane said. "If we could do that – find a way to halt the destruction of the insulin-producing beta cells or to simply protect them – that would really be something. Of course, because there is some insulin-resistance as well with LADA, it provides unique challenges when aiming for a cure."