Can C-Peptide Levels Improve?

By Determined2006 Latest Reply 2018-09-06 22:52:02 -0500
Started 2010-01-13 11:24:28 -0600

Hello everyone. I put this question under Type 2 even though the doctor still doesn't know what type I am yet. Here is my question and story.

I was diagnosed with Type 2 in 2006, but after a long time of uncontrolled sugars, mistreatments, etc, my sugars spun out of control. I finally switched endos and my new endo took an A1C and C-Peptide test on my first visit. Based on both tests, he determined that I was Type 1 and placed me on insulin. It devastated my life!

I have been on insulin for 3 months now and sugars are under control. So, I went to my endo yesterday, where he took another A1C and he said my levels were amazingly better, better than he thought it could be. Now he questions if I am Type 1 or just an insulin dependent Type 2. He has also ordered another C-Peptide test and I get the results next week.

I am really awaiting the C-Peptide results. My question is is it possible for the C-Peptide to improve once sugars are under control? If my A1C has improved, can my C-Peptide improve too? Could I really only be Type 2 and not Type 1?

4 replies

kdroberts 2010-01-13 12:42:28 -0600 Report

You are stumbling onto some interesting and tricky ground.

The short answer is no, c-peptide levels will not improve with an improved A1c. But as you may have guessed, there is a long and not well understood answer.

C-peptide is basically the other half of insulin from the pancreas. Insulin starts off as proinsulin which then splits into insulin and c-peptide. So, anyone who has low or no insulin production will have a low c-petide level. That can be a type 1, type 2 or any other type. A type 1 does not produce insulin because of an autoimmunce attack on the pancreas and it's not uncommon immediately after diagnosis and the start of insulin therapy for the pancreas to gain a temporary lease of life and churn out some insulin for a few hours/days/weeks. If this happened to you the signs would be shortly after starting insulin your requirement would suddenly be a lot lower than it was and then it would pretty suddenly increase shortly after. This is not often seen in type 2's who have lost insulin production because their pancreas has basically burned out rather than what happens to a type 1. What was your initial c-peptide level?

The easiest way to test for type 1 is do antibody tests, insulin, GAD65, DAG67 are good ones. Without some more testing it's very hard to know if you are 100% a type 1 or type 2, or another type like 1.5 or MODY.

emilyseevee 2018-09-06 22:52:02 -0500 Report

I just got my levels back and I'm struggling to understand them
Panc Islet Cells are Negative (<1:1-)
C-Peptide (ng/mL) (L) <0.1 (1.1-4.4-)
GAD-65 Autoab (U/mL) <5.00.(0-5.0-)
IA-2 Autoab (U/mL) (H) 1.9

Cheetaone 2016-09-22 11:22:58 -0500 Report

I'm trying to figure this same thing out. I had a c peptide done in 2014 which was .82 but when it was done in August 2016 it was .23. What in the world

Determined2006 2010-01-14 11:26:51 -0600 Report

Thanks for your reply. My doctor ran more tests and I should know the results by early nexct week. It will be interesting to see where I am. Maybe 1.5? I don't know. But, I am realy anxious about this.