I've read a number of studies about the somewhat different prognoses for people with a diagnosis of type 1 diabetes who have different antibody statuses. For instance, a longer honeymoon is associated with being positive for fewer antibodies. Lower A1cs are associated with being antibody negative. A higher recurrence risk (risk of a family member being diagnosed) is associated with antibody negative type 1 diabetes. And certain antibodies are more associated with certain genes.
Because of the age at which I was diagnosed- 17 years old- as well as because of who all was involved in my diagnosis, I was antibody tested at diagnosis. That is why I can tell you with a high degree of certainty that I have autoimmune diabetes.
But many people who are diagnosed with diabetes are diagnosed by doctors who feel certain of the diabetes type and never test.
In this study I read recently, participants were tested for five diabetes antibodies- the more antibodies tested, the better the chance of finding everybody who's positive for at least one.
More commonly people are only tested for three or four. The ones done most often are the ones I was positive for- the GAD and ICA 512. The ZnT8 I've heard good things about but seems to be too new of a test. Insulin antibodies sometimes turn positive from people having diabetes.
I was tested by both of the hospitals I was at at diagnosis for the same three antibodies.
The results were:
ICA 512 at hospital 1 was 0.952 with normal being less than 0.070.
ICA 512 at hospital 2 was 46.8 u/ml with normal being less than 0.8 u/ml.
I consider this the antibody that caused my diabetes. ICA 512 is most commonly found in younger people dx'd with type 1 diabetes.
Insulin antibody at both hospitals was undetectable.
GAD 65 at hospital 1 was 0.058 with normal being less than 0.050.
GAD 65 at hospital 2 was 4.1 U/mL with normal being 1.0 or less.
GAD-65 is the most common antibody in older people dx'd with type 1. It is frequently found in cases of LADA. As you can see, my levels of this antibody were only somewhat high.
I did have what I guess was a slow onset, but I was not dx'd early by any means.
How about you or your family member? Were you or they tested at diagnosis? What antibodies were you tested for, and what were the results? Did they have a honeymoon?