HBA1C vs Fasting Blood Glucose levels

NewTD2

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Is there a direct relationship between the fasting blood glucose levels with your HBA1C?

For example, if a fasting blood glucose level reads between 5-6 mmols/l, does it also mean a lower HBA1C?
 

KK123

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That is a very good question, I hope someone is able to answer it. I would presume that it is the fasting levels that mostly determine Hba1c levels as that presumably is the level that remains longest lasting in one's body?
 

Bluetit1802

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All I can say is I have never had average FBGs above the mid 5s, and the same for my pre-meal and bedtime levels. They have never been a problem for me almost since diagnosis.. As my post meal levels and HbA1c came down my FBG remained much as they have always been. So in my case there is no relationship whatsoever.
 

Rachox

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Mathematically if the HBA1c is literally an average of your blood sugar levels over three months. The fasting reading would have no more influence over the result than any other time of day. However I’m not sure it’s as simple as that!
 
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eggs11

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I am too wondering this - as suffer from DP and wondering how much it affects my HbA1c.
 

Bluetit1802

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I am too wondering this - as suffer from DP and wondering how much it affects my HbA1c.

Probably not a lot if the DP is short lived. If you are able to splash out on a Libre sensor this would tell you when you start to rise, by how much, and for how long. Failing that, extra tests?
 

eggs11

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Probably not a lot if the DP is short lived. If you are able to splash out on a Libre sensor this would tell you when you start to rise, by how much, and for how long. Failing that, extra tests?
I think a Libre is something I need to consider - is it painful to attach?
 

hankjam

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The FBG is a one off and may not be a true reflection of the daily average, so the relationship with HbAc1 is not likely to be a strong one.
 
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Freema

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Is there a direct relationship between the fasting blood glucose levels with your HBA1C?

For example, if a fasting blood glucose level reads between 5-6 mmols/l, does it also mean a lower HBA1C?

Lower than compared to what? My HbA1c is rather low compared to at what level my morning numbers are ... I think it differs from one person to the other, many in here has a much higher HbA1c than me but a much lower morning number around 4.5 than my average of around 5.8-6.0 mmol
 
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Mick1959

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I think a Libre is something I need to consider - is it painful to attach?
No! There is a loud click that makes me jump, but no pain. I get my husband to attach mine as I find it easier if you can use both hands. You learn so much.


I use a Freeestyle Libre, and as Bluetit1802 stated, there is no pain, but the loud click as you press the sensor into place using the applicator makes you jump the first time, as you steel yourself for the expected pain.

The first time I applied the sensor and lifted the applicator away, I thought I had not attached the sensor correctly and looked inside the applicator and on the floor for it, before checking the site I applied it to, to find it securely attached
 

Boo1979

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Is there a direct relationship between the fasting blood glucose levels with your HBA1C?

For example, if a fasting blood glucose level reads between 5-6 mmols/l, does it also mean a lower HBA1C?
Only if your FBG is truely indicative of your average control over the other 23-24 hours of the day, which is possible but v unlikely as there are too many variables at play that affect fbg specifically
 

Boo1979

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The first time I applied the sensor and lifted the applicator away, I thought I had not attached the sensor correctly and looked inside the applicator and on the floor for it, before checking the site I applied it to, to find it securely attached
Me too!
 

DavidGrahamJones

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Is there a direct relationship between the fasting blood glucose levels with your HBA1C?

For example, if a fasting blood glucose level reads between 5-6 mmols/l, does it also mean a lower HBA1C?

I don't think the relationship is direct. "Generally, FBS was a more accurate predictor for HbA1c compared with HbA1c as a predictor of FBS". (quoted from the ncbi.nlm link below. The discussion on this forum - https://www.diabetes.co.uk/forum/th...hip-between-hba1c-and-fasting-glucose.132200/ - seems to differ from this bit of research -
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3075530/.
 

britishpub

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I guess the 3 or 4 fasting tests you get every day, could be a reasonable indicator, but I doubt it would be an exact match.
 

Mbaker

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For me fbg in my case is for show and HbA1c for dough (those who have watched Bobby George at darts understand, otherwise apologies). I am beginning to see that the nuts (quite extreme amounts) in my diet keep my numbers in the low to mid 5's for extended times compared to other foods; I put this down to the fibre and the amount.
 
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Hiitsme

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I'm not sure for me there is much of a correlation. My fasting readings have climbed a bit over the last year but my HbA1c has only gone up 1 from 35 to 36. Before food readings mostly fine (often in 4's before evening meal) and often back to where I started by the 2 hour mark. Some people always seem to have very low fasting readings (on fasting reading page) but that doesn't necessarily mean that they have a very low HbA1c. I think I'm content with an HbA1c in mid 30's but I do get concerned when my fasting readings are in the 6's.
 

finsit

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Per couple of research studies i came across, they say a1c below 7% has stronger correlation with the postmeal levels, and as the a1c goes high, fasting levels contribute more.
 
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