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Can I calculate my own HbA1c using blood glucose readings?

notafanofsugar

notafanofsugar

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everything good for me! getting better though x
Was reading this page on HbA1c and had a bit of a question...

If i took my blood glucose levels for 3 month straight and averaged it, could i technically work back my HBA1c?

Also, if this was possible, and I was able to average it, would it be an average of all my readings of each day, from day 1 to 90, added together and divided by 90?

Just wondered! :)
 
Re: Can I calculate my own HbA1c using blood glucose reading

It just doesn't work, at least for me, I have tried to calculate what my HbA1c will be but every time I am way out.

Some claim some success, but as I said it doesn't work for me.

The problem is the finger test and the A1c are so different, different units, different methods, one is instant one is not, one is an average the other is not and so on.

I can say that low reading finger tests over months will usually result in a low HbA1c and vice versa, but if you ever manage to get them to correspond exactly I would rush out and buy a Lottery ticket, your luck is in :D

H
 
Re: Can I calculate my own HbA1c using blood glucose reading

Yes, it's possible to estimate HbA1c based on average BG, and vice versa. There's a tool on this very site, and it's based on a simple regression.
Also, if this was possible, and I was able to average it, would it be an average of all my readings of each day, from day 1 to 90, added together and divided by 90?
Click to expand...
Well, no. You have to divide it by the number of observations.

The problem is the finger test and the A1c are so different, different units, different methods, one is instant one is not, one is an average the other is not and so on.
Click to expand...
Why would any of that matter? You're fitting a linear model with various predictors (here, just HbA1c).
However, it is true that it is an estimate rather than a conversion of equivalent units (1m = 3ft and such)
 
Re: Can I calculate my own HbA1c using blood glucose reading

My job is to model drug concentrations in the human body. Cancer drugs though, not insulin. If you don't experience much variability in youryour glucose readingsto then yes, the on-line calculators are accurate to a degree. The data used to form these calculations themselves have a lot of variability, up to 40%, which is massive, statistically.

The magnitude of an Hba1c measurement is a measure of how much glucose has been exposed to the red blood cells, not the average amount of glucose in the blood over the red blood cells' 120 day lifetime. If you were to draw a graph of blood glucose vs time (time on the x-axis), the exposure is the area under the curve (imagine shading in everything under the line on the graph) commonly abbreviated to AUC. It is the AUC that is directly related to Hba1c.

That being said, if you use these on-line average glucose to hba1c calculators and your results are quite different to what you calculated (I'd say more than 30% different), then this may indicate that you either have too much variability in your sugar levels or you're having unseen highs.
 
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