C-peptide?

[Orion]

What exactly does this test measure and is it a blood test? Would it tell you how much insulin your pancreas is still producing? My endo has never mentioned it, I presume it would be helpful info for treatment? Is it good idea to have it done?

[Harold]

The C-peptide blood test measures the amount of c-peptides in your blood. Since c-petides are made along with insulin by beta islet cells the amount of insulin to c-peptides are directly proportional. So yes it would tell how much insulin you are producing. The synthetic insulin you inject does not have c-peptides . Since you know you are a type 1 I don't believe it would change your treatment although it may determine which subtype you are. Here's a couple of links.

Fulminant Type 1 (http://64.233.167.104/search?q=cache:pj9DgW36FuUJ:www.medscape.com/viewarticle/487566+peptide&hl=en)
C-Peptide Test Overview (http://webcenter.health.webmd.netscape.com/hw/diabetes_1_2/tu2817.asp)

[rzrbks]

According to my CDE, the only reason to have it done MIGHT be to determine if you are indeed T1 or T1.5. It won't change your treatment.

Some Ins. companies are loath to pay for pumps for T2.

So it might be useful for Ins. purposes but won't change much of anything else.

[may]

I am type 2.
My Dr. does the test on "all" of his diabetic patients once a yr.

[hundredpercent]

What if C-peptide is normal, and insulin is low??

[Harold]

What if C-peptide is normal, and insulin is low??
C-peptide is a portion of insulin therefore released in equal amounts by the pancrease.

From WebMD (http://webcenter.health.webmd.netscape.com/hw/diabetes_1_2/tu2817.asp);
C-peptide testing can also help determine the cause of low blood sugar (hypoglycemia). There are several causes of hypoglycemia, including the excessive use of medication to treat diabetes or the presence of a noncancerous growth (tumor) in the pancreas called an insulinoma. Because man-made (synthetic) insulin does not contain C-peptide, a person with a low blood sugar level from the inappropriate use of insulin will have a low C-peptide level. An insulinoma causes the pancreas to release excessive amounts of insulin, which causes blood sugar levels to decrease (hypoglycemia). A person with an insulinoma will have a high level of C-peptide in the blood.

[hundredpercent]

I know that C-peptide is a portion of insuline. That is why am I confused with such a results of testing.

[may]

Some people believe, and rightfully so that their beta cells have been burned out. Some believe it can happen from certain diabetic medications. They won't take those medications, yet do they "really" even know where they stand with there C-peptide test results. I don't see how anyone can know there beta cells aren't working anymore without the test.
One of my questions is..if a persons beta cells are at 3.0, considered "good" should the Dr. put them on Isulins, or continue with the orals.
I know several type 2's that the Dr.s have switched off the orals, and put them on Humalog and Lantus. Their HA1C are lowered it appears..but aren't they putting more hormones into their bodies and thereby maybe making them eat more??
Thanks for comments in advance!

[MarkMunday]

What if C-peptide is normal, and insulin is low??
That does sound odd. Have you discussed this with your endo? To me, it suggests that your pancreas is producing lots of insulin but it isn't having the desired effect. Could you be insulin resistant? Or maybe this just happens in the honeymoon period.

Cheers,

Mark ;)

[hundredpercent]

That does sound odd. Have you discussed this with your endo? To me, it suggests that your pancreas is producing lots of insulin but it isn't having the desired effect. Could you be insulin resistant? Or maybe this just happens in the honeymoon period.

Cheers,

Mark ;)

No. Insulin is low, C-peptide is normal. Endo says nothing about it. Which is the possible longest period of honeymoon? One year?

[Harold]

Very interesting! Everything I've read sofar indicates that the C-peptide test is the standard for determining how much insulin the pancrease produces. Do you know what test, besides the c-peptide, were run to determine the low insulin level. Maybe one of the more medically trained would have a better idea or the resources to answer this intriguing condition.

Don't believe anyone has learned to tell how long a honeymoon period will last. Have heard a few say theirs lasted for as long as a year or year and a half.

[JasonSmithMT]

Very interesting! Everything I've read sofar indicates that the C-peptide test is the standard for determining how much insulin the pancrease produces. Do you know what test, besides the c-peptide, were run to determine the low insulin level. Maybe one of the more medically trained would have a better idea or the resources to answer this intriguing condition.

Don't believe anyone has learned to tell how long a honeymoon period will last. Have heard a few say theirs lasted for as long as a year or year and a half.

The lab can directly test for total insulin level in the blood and in many cases is the preferred method for gauging insulin secretion. What the test can't tell is if it is exogenous insulin or endogenous insulin ... i.e. insulin injected or insulin made by the body. This is where the C-peptide test comes in handy. C-peptide will closely represent the endogenous secretion of insulin for those that inject insulin. In theory, C-peptide and insulin is produced in equal amounts ... although it is not always the case as we see.

Jason

[may]

Now, I'm getting more confused.
I was told I was type 11, and have doctored for it for over 15..nearly 20 years.
First I was on orals and exercise.
The past few years I have been put on different insulins besides.
Currently is Lantus and Humalog.
They give me good low readings, and great if all your looking at is the HA1C result. I look at how I feal also, and am about to drop the Humalog...I know it is making me to hungry!
I used to take 75/25 twice a day before trying this regiment. I never felt hungry like I do now.
My last, and next to last C-Peptide was 3.0.

I grew up with Type 1 or Type 2.
A very nice link was placed here not long ago explaining type 1.5.
But I don't hear my Dr. using that or "just" insulin resistance.

In SIMPLE terms, maybe someone could help out with that.
Do insulin resistance people get meds?
And where does pre-diabetes fit in.

I did that 4-5 hr. test when they told me I was diabetic.
Don't they do that anymore.
I thought you either were or wern't diabetic!!

You thoughts appreciated.
Help us older diabetices out....sometimes the younger ones are so helpful!

[rzrbks]

I did that 4-5 hr. test when they told me I was diabetic.
Don't they do that anymore.
I thought you either were or wern't diabetic!!

Like every other disease, research has indicated that if the disease is caught early enough {pre-diabetes} then preventative actions may slow the growth of the disease for many years

Plus, the diagnostic tools are improving all the time and therefore, medical professionals are able to pinpoint disease growth better/faster.

Never heard of the 4-5 hr. test

I test before and at 2 hr after eating>>>> and pretty much when I think something might be "Off"

[may]

The 4-5 hr. test is a fasting glucose given in the Dr.s office to determine if your diabetic or not.

[rzrbks]

may

The 4-5 hr. test is a fasting glucose given in the Dr.s office to determine if your diabetic or not.


:o , Geez, I'd forgotten I had to do that one.

In my case though, they had already done that, sorta. 590/32.8 reading at the eye Dr.'s office about 5 or 6 hours since the last meal. :D

Then the PCP did one the next day at his office, and it was onto the Insulin I went :hypocrite :p

[may]

I am sorry to hear that....you certainly were "high"
Hope you are getting those numbers down, and doing well in your management...often it takes considerable time and work!

The oral glucose tolerance test (OGTT / GTT) is the test I was refering to
that may also be used to diagnose diabetes and pre-diabetes but, according to the American Diabetes Association, two tests (either the fasting glucose or the OGTT) should be done at different times in order to confirm the diagnosis. The OGTT involves a fasting glucose, followed by the patient drinking a standard amount of a glucose solution to "challenge" their system, followed by another glucose test two hours later.

In my part of the county I know the endos are still using the oral glucose tolerance test to diagnose. I would imagine the HA1C may be a good indicator also.

[rzrbks]

may
I am sorry to hear that....you certainly were "high"
Hope you are getting those numbers down,

Thanks for the words of encouragement. 1st A1c after Dx'd was 10.3, and that was after I'd been on insulin for several weeks. But in the last two years, worst A1c has been 5.7 :thumbsup:

That's why I can keep dodging the CDE and her recommendations on going on a pump. :D