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HBA1C & FBG Who controls who ?

HICHAM_T2

HICHAM_T2

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Morocco
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Type 2
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Hi I want to ask
Who controls who HbA1c control FBG or FBG control Hba1c ?
Thanks for everyone who curved this information


Hicham
 
Neither really
Hba1c and fbg will both give an indication of overall control but in different ways
Hba1c will be high if the average bg over the whole day is high. A high fbg may or may not lead on to a high BG across the day and therefore a high Hba1c- the only way to tell is to test across the whole day
 
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HbA1c is an effect caused by blood glucose levels including the fasting level.
 
Mr_Pot said:
HbA1c is an effect caused by blood glucose levels including the fasting level.
Click to expand...
Boo1979 said:
Neither really
Hba1c and fbg will both give an indication of overall control but in different ways
Hba1c will be high if the average bg over the whole day is high. A high fbg may or may not lead on to a high BG across the day and therefore a high Hba1c- the only way to tell is to test across the whole day
Click to expand...
Thanks a lot

Yes I know that the higher the blood glucose
Hba1c levels also high

But I know that the higher the hemoglobin A1C the more difficult the control BG and when. We have BG higher that mean difficult to control A1C

I think it's a closed loop
 
Neither. They don't compare.
I have never had a high FBG (always low to mid 5s) but I have had high post meal levels, so my HbA1c was not low. Some people have constant high FBGs but manage to get low HbA1cs.
 
Its only a closed loop because one reflects the other so they are dependent on each other as the the overall hba1c simply reflects and is dependent on the average Bg value
 
Bluetit1802 said:
Neither. They don't compare.
I have never had a high FBG (always low to mid 5s) but I have had high post meal levels, so my HbA1c was not low. Some people have constant high FBGs but manage to get low HbA1cs.
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How So ?the first time I hear this !
 
hichamgsm said:
How So ?the first time I hear this !
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I have never had a problem with fasting numbers or pre-meal and bedtime levels. That's the way I am. My post meal levels were too high and took up to 3 hours to return to base until I cut the carbs right down.
 
In the HbA1c test the glycation rate is an average measurement, there is no way of measuring which cells are glycated by fbg or by prandial glucose. This is a different test to a fasting glucose reading when we know we have not eaten for some hours so we can measure with a home glucometer.
 
I think the average will be between the top and lowest BG
Example
5 mmol and 7 mmol and 9 mmol = 21 mmol 21/3 = 7 mmol
 
I am the other way round, I have highish fasting levels and a lowish HBA1c. As others have said HBA1C is jusr the average of 24/7 over 8-12 weeks.
 
Alison Campbell said:
I am the other way round, I have highish fasting levels and a lowish HBA1c. As others have said HBA1C is jusr the average of 24/7 over 8-12 weeks.
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It may decline at some times dramatically
Maybe that's why

Between the sharp drop and the rise you will get an average result
Example
4 mmol + 10 mmol = 14/2 = 7
Do you have many hypo ?
 
This is not a linear relationship for some. My HbA1c is much higher than my meter predicts (My meter has been tested to be accurate), and I note that my fbg is quite low, but others with higher fbg's sometimes have lower HbA1c's than I do. This is one of the reasons I do one meal a day at least 5 out of 7 days, so that I can see if I am say below 5 for at least 2 thirds of the day and my food spike is minimal, and a go to bed say at 5.2 or below, this should be reflected in my next month's HbA1c (My home test A1CNow test says 34, which I would be happy with if translated in the lab test next month).

The length of life of the glycated sugar on the red blood cells is what the main variable is for HbA1c, and this might not be the same for all, but averages at circa every 3 months for life span.
 
Mbaker said:
My HbA1c is much higher than my meter predicts (My meter has been tested to be accurate), and I note that my fbg is quite low, but others with higher fbg's sometimes have lower HbA1c's than I do.
Click to expand...

Same with me. My FBG is low. My HbA1c is considerably higher than my meter averages and also my Libre readings. I self diagnose non-standard red blood cells and rely on my meter to tell me how I'm doing. My HbA1c is just for my nurse, but even though it doesn't fairly represent my control, it is useful to watch for trends..
 
Mbaker said:
This is not a linear relationship for some. My HbA1c is much higher than my meter predicts (My meter has been tested to be accurate), and I note that my fbg is quite low, but others with higher fbg's sometimes have lower HbA1c's than I do. This is one of the reasons I do one meal a day at least 5 out of 7 days, so that I can see if I am say below 5 for at least 2 thirds of the day and my food spike is minimal, and a go to bed say at 5.2 or below, this should be reflected in my next month's HbA1c (My home test A1CNow test says 34, which I would be happy with if translated in the lab test next month).

The length of life of the glycated sugar on the red blood cells is what the main variable is for HbA1c, and this might not be the same for all, but averages at circa every 3 months for life span.
Click to expand...
This seems to be a very logical reason
Home measurements may be inaccurate
 
Bluetit1802 said:
as may the HbA1c
Click to expand...

Indeed. On another thread about whether there were any country-wide stats on a1c, I'd posted a link to the Scottish Diabetes Surveys. I'm not into stats (my eyes glaze over when I see a spreadsheet), but was having a flick through it and noticed this caveat:

Screenshot_2018-03-11-16-19-04.png
 
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