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Type 2 C-peptide reading?

Alan9009

Alan9009

Well-Known Member
Messages
49
I recently had a C-peptide test carried out. It came back as 476 pmol/l and stated normal, no action needed. I am on Gliclazide 120mg (m.r.) Pioglitazone 30mg, Metformin 2000mg and Atorvastatin 20mg daily. I fasted for the test and did not take my evening or morning medication prior to the test. I had the test at 1pm in the afternoon, so I’m guessing my medication was not a heavily influencing factor in the test? Can anyone explain the C-peptide reading of 476 pmol/l in more/better detail? Also can it be done in laymens terms, as I’m not knowledgable in medical terms in any way?
 
Alan9009 said:
I recently had a C-peptide test carried out. It came back as 476 pmol/l and stated normal, no action needed. I am on Gliclazide 120mg (m.r.) Pioglitazone 30mg, Metformin 2000mg and Atorvastatin 20mg daily. I fasted for the test and did not take my evening or morning medication prior to the test. I had the test at 1pm in the afternoon, so I’m guessing my medication was not a heavily influencing factor in the test? Can anyone explain the C-peptide reading of 476 pmol/l in more/better detail? Also can it be done in laymens terms, as I’m not knowledgable in medical terms in any way?
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Hi. I've attached a jpg showing C-Peptide ranges and what they imply. A level of 476mmol implies T2 and 'normal'. C-Peptide measurement isn't a very exact science but high means T2 and low means T1 in general terms. The implication for you is that you have adequate insulin production although not overloaded with it as some are. It therefore means you may have some insulin resistance which a low-carb diet and exercise may help with. What is your BMI? BTW are you aware that Pioglitazone has some side effects which although not common can be serious. You may have been advised already but if not have a look at the NICE web page: https://bnf.nice.org.uk/drug/pioglitazone.html.
 
Alan9009 said:
I recently had a C-peptide test carried out. It came back as 476 pmol/l and stated normal, no action needed. I am on Gliclazide 120mg (m.r.) Pioglitazone 30mg, Metformin 2000mg and Atorvastatin 20mg daily. I fasted for the test and did not take my evening or morning medication prior to the test. I had the test at 1pm in the afternoon, so I’m guessing my medication was not a heavily influencing factor in the test? Can anyone explain the C-peptide reading of 476 pmol/l in more/better detail? Also can it be done in laymens terms, as I’m not knowledgable in medical terms in any way?
Click to expand...
Hi @Alan9009 The C-peptide test is a measure of how much insulin your pancreas produces under the test conditions (e.g., fasting, etc). It is cheaper and easier to do than directly measuring insulin production. To properly understand your result you should discuss with your healthcare team, not just this result, but in context of your overall diabetes and health control - did you have fasting blood glucose and HBAc1 done at the same time? Have you had GAD and other anitbodies tests? Do you have a meter and can regularly track your BG results?

A higher than normal C-peptide result is an indication of overproduction of insulin due to insulin resistance, typical in Type 2 diabetes but can be present in metabolic syndrome and pre-diabetes before overt diabetes happens. A lower than normal C-peptide result can be due to either pancreas beta cell autoimmune destruction as in Type 1 diabetes, or in case of severe or longstanding insulin resistance where the beta cells suffer from "burnout" - why some Type 2s may need to progress to injecting insulin. If not already explained to you it would be useful to ask your HCT why they ordered this test in your case.
 
Daibell said:
Hi. I've attached a jpg showing C-Peptide ranges and what they imply. A level of 476mmol implies T2 and 'normal'. C-Peptide measurement isn't a very exact science but high means T2 and low means T1 in general terms. The implication for you is that you have adequate insulin production although not overloaded with it as some are. It therefore means you may have some insulin resistance which a low-carb diet and exercise may help with. What is your BMI? BTW are you aware that Pioglitazone has some side effects which although not common can be serious. You may have been advised already but if not have a look at the NICE web page: https://bnf.nice.org.uk/drug/pioglitazone.html.
Click to expand...

Hi Daisybell,

My BMI was about 25.7 pre diabetes. It’s now about 24.5. I am tall and reasonably fit and always have been. I was rather shocked when diagnosed and didn’t fit the type 2 body type. Recently two other family members have been diagnosed with type two and type one, I’m assuming it’s genetic. My medication has been increased year on year and I’ve had trouble keeping my BG level down, given I exercise and have a reasonably low carb diet. That’s why I asked for the C-peptide test. Regarding Pioglitazone, yes I’ve read a bit about it’s side effects and know it’s banned in certain countries. It has helped get my BG down though. I don’t really have any say in what I’m prescribed, but I take on board your concerns and will raise this at my next meet with my DN meeting. Thanks for your reply/advice, it’s really appreciated.

Alan.
 
oldgreymare said:
Hi @Alan9009 The C-peptide test is a measure of how much insulin your pancreas produces under the test conditions (e.g., fasting, etc). It is cheaper and easier to do than directly measuring insulin production. To properly understand your result you should discuss with your healthcare team, not just this result, but in context of your overall diabetes and health control - did you have fasting blood glucose and HBAc1 done at the same time? Have you had GAD and other anitbodies tests? Do you have a meter and can regularly track your BG results?

A higher than normal C-peptide result is an indication of overproduction of insulin due to insulin resistance, typical in Type 2 diabetes but can be present in metabolic syndrome and pre-diabetes before overt diabetes happens. A lower than normal C-peptide result can be due to either pancreas beta cell autoimmune destruction as in Type 1 diabetes, or in case of severe or longstanding insulin resistance where the beta cells suffer from "burnout" - why some Type 2s may need to progress to injecting insulin. If not already explained to you it would be useful to ask your HCT why they ordered this test in your case.
Click to expand...

Hi Oldgreymare,

Thanks so much for your response. I have had regular HbA1c tests and am testing my blood regularly. I asked for a C-peptide test because my diabetes seems to be progressing at a fast rate and I am feeling very unwel. I get periods of feeling well, but I believe this is due to my medication combined with a low-carb diet. My diebetes gets worse around mid November every year - prompting me to question what is going on, with no obvious reason. I’ll be using your advice to help me understand my condition better, it all helps.

Kind regards, Alan.
 
Alan9009 said:
Hi Daisybell,

My BMI was about 25.7 pre diabetes. It’s now about 24.5. I am tall and reasonably fit and always have been. I was rather shocked when diagnosed and didn’t fit the type 2 body type. Recently two other family members have been diagnosed with type two and type one, I’m assuming it’s genetic. My medication has been increased year on year and I’ve had trouble keeping my BG level down, given I exercise and have a reasonably low carb diet. That’s why I asked for the C-peptide test. Regarding Pioglitazone, yes I’ve read a bit about it’s side effects and know it’s banned in certain countries. It has helped get my BG down though. I don’t really have any say in what I’m prescribed, but I take on board your concerns and will raise this at my next meet with my DN meeting. Thanks for your reply/advice, it’s really appreciated.

Alan.
Click to expand...
Hi. As a patient you always have a say in your treatment and the drugs prescribed and a right to refuse. At one point my GP was going to add Pioglitazone and I refused. Instead she added Sitagliptin in addition to my 320mg Gliclazide which although not as good has few side effects. It does look as though your pancreas is gradually declining with med increase possibly needed. Hopefully you can avoid insulin which I eventually went to.
 
oldgreymare said:
Hi @Alan9009 The C-peptide test is a measure of how much insulin your pancreas produces under the test conditions (e.g., fasting, etc). It is cheaper and easier to do than directly measuring insulin production. To properly understand your result you should discuss with your healthcare team, not just this result, but in context of your overall diabetes and health control - did you have fasting blood glucose and HBAc1 done at the same time? Have you had GAD and other anitbodies tests? Do you have a meter and can regularly track your BG results?

A higher than normal C-peptide result is an indication of overproduction of insulin due to insulin resistance, typical in Type 2 diabetes but can be present in metabolic syndrome and pre-diabetes before overt diabetes happens. A lower than normal C-peptide result can be due to either pancreas beta cell autoimmune destruction as in Type 1 diabetes, or in case of severe or longstanding insulin resistance where the beta cells suffer from "burnout" - why some Type 2s may need to progress to injecting insulin. If not already explained to you it would be useful to ask your HCT why they ordered this test in your case.
Click to expand...
I would add to beta cell destruction, damage caused by a virus. I believe this is more common than the medics accept which is why GAD can be negative but C-Peptide level low as it is in my case.
 
Daibell said:
I would add to beta cell destruction, damage caused by a virus. I believe this is more common than the medics accept which is why GAD can be negative but C-Peptide level low as it is in my case.
Click to expand...

I was going to try and get a GAD test done privately, which has been a bit of a palaver for one reason and another. I’m not sure about getting it done now though given my recent C-peptide result. I feel that getting it done, as it’s only about £100 may give me more insight into what’s going on with my pancreas.
 
Alan9009 said:
I was going to try and get a GAD test done privately, which has been a bit of a palaver for one reason and another. I’m not sure about getting it done now though given my recent C-peptide result. I feel that getting it done, as it’s only about £100 may give me more insight into what’s going on with my pancreas.
Click to expand...

Hi Daibel,

Has going onto insulin proved difficult for you?
 
Alan9009 said:
Hi Daibel,

Has going onto insulin proved difficult for you?
Click to expand...
I would get the GAD test done if you can although I still think the C-Peptide is more important. I've had both done privately; the GAD was negative but the C-Peptide low. I would say insulin is a nuisance and not a problem. When you get to the point where low-carbing and all the tablets aren't working you just don't know what to do. Insulin Basal/Bolus (two different insulins) and 5/6 injections per day sounds bad but 3 of those are when getting up or going to bed. You always have to be aware that there isn't hypo round the corner which means remembering to test if in doubt. You also must test before and during driving. The good news is that you can eat fairly freely and what you want although you may gain weight if you eat too many carbs and have large BS swings.
 
Daibell said:
I would get the GAD test done if you can although I still think the C-Peptide is more important. I've had both done privately; the GAD was negative but the C-Peptide low. I would say insulin is a nuisance and not a problem. When you get to the point where low-carbing and all the tablets aren't working you just don't know what to do. Insulin Basal/Bolus (two different insulins) and 5/6 injections per day sounds bad but 3 of those are when getting up or going to bed. You always have to be aware that there isn't hypo round the corner which means remembering to test if in doubt. You also must test before and during driving. The good news is that you can eat fairly freely and what you want although you may gain weight if you eat too many carbs and have large BS swings.
Click to expand...

Hi Daibell,

Thank you for your advice and sharing your experience. I’ve had it put to me today that insulin may be an option, by my DN. She is going to refer me to the diabetic specialist nurse for a consultation and to look at the viability of it.

Regards, Alan.
 
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