
January 30, 2005
LADA and MODY
Question from Austin, Texas, USA:
I was diagnosed with diabetes about seven years ago at age 33. At time of diagnosis, I had fasting sugars around 400 mg/dl [22.2 mmol/L] and had lost 60 pounds. My internist assumed I had type 2 and tried various combinations of medications to no avail and eventually put me on insulin. Recently, my insulin requirements have gone up dramatically, so my diabetes team tried Glucophage again. All it did was make me sick to my stomach, so I asked to have a C-Peptide and GAD 65 antibody tests run. My GAD 65 was 2.2 U/mL (normal range less than 0.5) and my C-Peptide level was 0.9 ng/ml (normal range 1.1 to 5.0).
Based on what I can determine from this, I’m GAD antibody positive, and below the line on insulin production. I asked the doctor, but he said I was not positive for GAD 65 antibody, but would still be classified as LADA. Am I misreading this?
Answer:
LADA is still a form of type 1 diabetes. You have type 1 diabetes. The antibody levels are positive and you have a low level of a marker for insulin secretion. The difference between LADA and usual type 1 diabetes is that the evolution of LADA is slower up front. Years after the diagnosis, there may not be much difference as both result in frank loss of insulin secretion and need for insulin.
JTL