How often did you test c-peptide & antibodies?

I’ve read that some people here present negative on antibodies at first, then later on, present positive. I’m curious for those who took a while, how often did you test antibodies? I’m wondering if, considering my results, it would be worth it to retest again.

Quick background: I’ve been experiencing problems with blood sugar for the past 7 months. I get postprandial spikes over 200 and sometimes have rebounds that go as low as 50. This is new for me; I did not experience fluctuations like this a year ago.
I originally got everything lab tested over 3 months ago at the beginning of August. FBG 90 and hba1c 5.2 (so that’s normal as I expected). I took an OGTT which showed 233 at 1 hour and 50 exactly at the 3rd hour. I did another OGTT with insulin which showed I made a below average amount of insulin, and same glucose response. C-peptide at the time was 0.6. No antibodies though. (Slim male. I exercise 4x/week. I eat very healthy, and gluten free btw because I do have Celiac).

For the past month, my FBG has been higher (ranges 98-106 in the morning, when previously I used to be in the mid-80s to low 90s). I realize this could just be the dawn phenomenon (well what it looks like for a very early stage LADA at least). So I decided to retake the c-peptide. I intentionally carbo-loaded heavy for the 4 days leading up to the test (definitely ate more carbs this time than last time). I got 0.6 again. The literal exact same as last time. I’m considering testing hba1c and antibodies again but I might just wait several more months to save money though.

How often did you test your antibodies? Considering my FBG is up and my c peptide is the same, would you recommend another hba1c / antibodies, or continue waiting?
Don’t get me wrong – I’m not exactly rushing or even wanting to be a diabetic. Diagnostically, I don’t even meet T2 standards (unless you count the 200+ postprandial). But I would like to get this problem under control and have a way to combat these BG spikes. And in my mind, IF I’m early LADA, I’d rather just get this out of the way with.

I was tested while in dka in icu for antibodies which were pos for gad. C peptide was tested when I was first in dka at my doc office, he would never give me that result.

And in hospital, it was very low and then again 2 months after maybe, and later in a research trial, it was non existent by then. I have forgotten the levels something like .o something.

My D went undiagnosed for at least two years by numerous docs and then was misdiagnosed by my own doc while I was already in dka. I wish I had had the chance to treat early and avoid what happened.

I hope you get this figured out. Eating lower carb could help with those highs and lows.

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I have had diabetes for 46 years plus. I have never been tested for either.

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I was tested once to qualify for my pump and CGM. It was later suggested after move related change of endo that it would be interesting to retest. I declined, since the only change to treatment that could result is loss of coverage for the pump and CGM.

I’ve been a Type 1 for 65 years. Never tested for either


I wouldn’t need to get a c-pep or antibody with those numbers.
I would reduce my carbs so I don’t get the high, that then goes too low. Commonly called a sugar crash. It’s possible you are developing reactive hypoglycaemia. There can also be other reasons, so if you continue to see below 60, I would seek a medical dx

I think if you are a type 1, antibodies don’t show up later if they were negative to start, and if you already have diabetes from the attack on your cells from the antibodies that are tested for??? I could be wrong about that but I believe they might even be at the highest earlier versus later. I have heard of type 1’s that have had diabetes for years that their antibody test can go to zero or almost zero as there is nothing much to attack anymore.

I don’t mean you can’t get antibodies later, and hence type 1 later. It’s just that if you are having blood sugar issues and it is from the process that starts the destruction of insulin producing cells, you would already have those antibodies.

However there are some strange forms of diabetes out there. One is where you have negative antibodies but you don’t make insulin. My DE is one of those, negative antibodies but doesn’t make any insulin. They have not a clue why. One of those unexplained phenomena. You could fit into this category. I really don’t know how long it takes when this happens to lose all your insulin producing cells.

Sometimes loss of insulin producing cells can be explained by trauma to the pancreas or steroid use. In both those cases some people can get back the production of insulin over time.

Keep in mind I don’t know what tests you had. There are several antibody tests and a lot of time they just test the most common. The GAD test.

I think it has to be many years of type 1 at the point where you need insulin and have almost none left etc. by the time antibodies no longer show up. Mine were positive while in dka with next to no insulin production.

Also I believe it has been suggested if not proven that even in long term type 1 the body is still trying to make beta cells which is why people on immune therapies often have an easier time with bg management.

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My endo says “one and done”. Once levels are established there is no need to test again unless an insurance company wants new data.

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I recently switched to new pump, and with new insurance. Been type 1 since childhood. Insurance company wanted C-peptide, so it was the first one done after 50+ years of T1D.

Not on medicare, but c-peptide test is also required for insulin pump coverage.

As far as I know, anti-bodies never tested.

When I went on Medicare they required a C-peptide for diabetes coverage.


I also was diagnosed a long, long time ago and these tests were not available. Over the years, there was never a need for the test.
Although, when I volunteered for the Viactye stem cell study, I had to be tested to make sure I was not making any insulin. Shocking news, no insulin! They just tested for c-peptides not antibodies. Just don’t know much about these tests and how necessary it would be to continue testing. Since things are heading down the diabetes track, it seems like it is inevitable.

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Diagnosed T2 26 years ago and become insulin dependent 5 years later. I have never been tested for antibodies, but my Endo includes a c-peptide on all my quarterly blood tests - consistently < 0.01 since going on the pump 8 years ago. Prior to going on the pump my A1c would occasionally go above 10 and my c-peptide would go up to 0.6.

I was tested once because I demanded it from a diabetes fellow and she complied to prove me wrong. I was right. This is how a lot of Lada folks are being discovered.


I was diagnosed in 1986 (extreme DKA, BG 998), and I don’t think that I’ve ever been tested, not even for pump or CGM coverage. The endo said that I needed the CGM, and the CGM data made the argument for the pump. The endo gave the orders, and that was +3 years ago. When did c-peptide tests become available?

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I was diagnosed in 1982, and the diagnosis was confirmed by a test no more complicated than sticking Testape in my urine and having it turn jet black immediately.

Two years later,I had a C-Peptide test in the 1984, it was part of screening required for enrolling in the DCCT study. That said, I chose not to go into the DCCT study (at the time if you were in the “control” group you were not allowed to do home bg testing, which I was already doing. Very shortly afterwards they changed their tune and allowed home bg testing for all in the study) and I don’t know what the result of the C-peptide test was (presumably it showed I was producing no insulin).

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I’ve never had these tests either. Diagnosed in '89 by my school nurse who did a urinalysis dip on me, because I had lost enough weight to weigh less in 3rd grade than when I started at the school for pre-school… And had all the classic symptoms. She took me straight to the hospital where they confirmed with a simple glucose test. It was over 1,500 mg/dl. A record at that particular hospital, given all the hushed tones and gasping amongst the med students.

I had ketones, but I didn’t go into the miserably sick DKA until they administered insulin.

No other confirmation was ever required. I guess things have changed since.

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I had them originally when diagnosed but I’ve never have been asked to have them done again. I have had the same insurance but am on Medicare and that insurance is now a secondary insurance.

I was tested twice. Once for a clinical research trial of a potential treatment for peripheral diabetic neuropathy and the second was to qualify for the Faustmann Lab BCG trial. I have had type 1 since May 1975 and have no measurable C-peptide.

I wasn’t tested either because I had the classic type 1 symptoms and onset.
My first urgent care doc thought I could be type 2. However. 6’3 and 155 lbs.
as soon as I saw an endo he diagnosed me as type 1 in Dka and admitted me to the hospital.
However I did a inhaled insulin study in 99 and they tested antibodies and I was positive. It was a requirement to get in the study.