T1, T1.5 or T2?


Back in December 2017 I switched endocrinologists.

My old one labeled me T2 and kept giving me orals which helped some but not very much. After trying victoza and that not doing much, my old endo stopped all orals and put me on Novolog and kept the Victoza. My A1C went down some, bust still in the low 7 A1C range.

My new doc did antibody tests 12/19/2017 and found:

GAD-65 <5
IAA <5
IA2 < 1
CPEP 0.7

Unsure what time of day the cpep was run and if it was fasting or not.

He said Anything 0.8 or lower was clinically Type 1 and if I was on medicare, I’d meet the criteria for T1 but since I was already on insulin, further testing was a waste of time since it would be the same treatment. He also said that if it would help for insurance, he would re-label me T1.

I’m currently on a Dex G6 and omnipod but highly insulin resistant running anywhere from a low of 60 units per day of insulin to a max of 120 units depending on what I eat.

But now I want to branch out and talk about Diabetes on the boards and on facebook.

Just not sure how to label myself. Am I an insulin dependent T2 or a misdiagnosed T2 turned T1 (1.5)?

A1Cs have been pretty steady with the latest being 6.0 on 2/5/2019 but I’m not doing all that great on preventing highs and lows.

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So putting a type on what you have is somewhat of a tough call. You have a negative test for GAD antibodies, so in my understanding that rules out classic Type 1. You also have a test on the low normal end of the C-peptide range, hopefully this was a fasting blood test, otherwise I don’t think the C-Pep is valid. The fact that you have low levels of GAD and low normal C-Pep, would mean to me you have type 2 that has progressed to insulin dependence with a low to moderate amount of insulin resistance. Just as a point of comparison you are using double to triple the amount of insulin my 16 year old Type 1 son does.

In our diabetes travels I have met people that meet the classic definition of Type 1, 1.5 and 2. But I also know a couple of people that have a variant of Type 1.5 that includes a really high level of insulin resistance, think like having to take 500+ units of insulin a day. So there are outliers at each type definition.

The interesting thing, is that once you progress to insulin, regardless of type, you have more in common with the Type 1 crowd than not.


Thanks Chris. I think the reason my new endo didn’t do further testing was that because he knew I was already on insulin and wanted to continue that, so he said that the label was a moot issue since a T1 would be treated the same way.

I just wanted clarification when I write so that I know what to call myself and how to properly fill out my profile(s) on various boards.

And FWIW, I’m fairly certain that the blood work was fasting as I usually show up fasting when I’m not sure if fasting is needed or not.


That’s what I’d call it. I think “Type 1” is the old but still widely-used term for absolute insulin deficiency of auto-immune origin. Without the auto-antibodies showing up in your labs, that would indicate you don’t have type 1. Type 2 does tend to progress to insulin dependence as the overtaxed pancreas wears out.

That said, sometimes doctors will label an insulin-dependent type 2 as “type 1” for strategic reasons. Calling it type 1 may avoid problems with insurance and with visits to other doctors by making it clear that insulin is required. It can also avoid the false and undeserved stigma that some ignorant people attach to the type 2 label based on the incorrect and absurd notion that a person who has type 2 insulin somehow caused or deserves to have their disease because of their lifestyle choices. That’s as wrong as saying someone who has a heart attack or cancer deserves it and brought it on themselves because they didn’t eat right.


I thought the GAD test was not applicable for someone already taking insulin?

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That’s correct Kenrick