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HbA1c

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mjpater

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Can someone identify for me the entities involved in the units "%" and "mmol/mol" when expressing HbA1c values? Taking saline (sodium chloride) aqueous solutions as an example, a 10% solution would contain 10g of NaCl (sodium chloride) per 100 ml of water, assuming that the percentage was mass by volume. A 10 mmol/mol solution would contain 10 mmol of NaCl (i.e. about 0.085 g) per mol of water (i.e. 18 g).

I am not sure that this question is meaningful, because the two methods of expression appear to be on different bases. For example, HbA1c values below a certain level give negative values in terms of mmol/mol!
 
mjpater said:
am not sure that this question is meaningful, because the two methods of expression appear to be on different bases. For example, HbA1c values below a certain level give negative values in terms of mmol/mol!
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Hi there! You don't get a negative value actually, because there isn't a straight-line conversion from mmol to HbA1c. What happens is that the lower the mmol reading is, the nearer it gets to the HbA1c. If you want to convert average blood sugar levels, as taken with a meter of your own, to HbA1c, the calculation is (BloodSugar in mmol+4.29)/1.98 This is correct providing you have a fairly newish meter which is referenced to blood plasma - some older ones aren't, and the calculation has to be amended.
They are of course different currencies being used here, the one measuring the saturation level of glycated haemoglobin in % (although a new currency is now introduced measuring differently again, using IFCC units) HbA1c is an average over 2 to 3 months, with the last months blood sugar levels having the greatest affect, whereas your meter reads at a moment in time.
Good luck and welcome!
 
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