A1C-is it possible

[jeggeman31]

In the first week of October I had an A1C done via blood draw. It came back 6.6 (this was done by my family Dr) Well my Endo did another A1C test today via the kit that uses the blood from a finger stick, because they did not know I already had one done, and until they did it did not know they was going to do it.

Anyway that came back 6.2

Can an A1C drop like that in such a short amount of time? I know it is no huge drop, but my goal is to have an A1C below 6.0 and was just wondering what one is more like the true reading if in-fact it can't drop like that.

[Gabby123]

Mine went from a 6.0 to a 5.9 in 3 weeks.It mainly goes by the last 30 days also.

[Real4]

With two different tests, that difference is probably just noise; that is within the magin of error for the tests involved. Gabby though is also correct, although A1C is always touted as a 3 month average, it, by nature, a weighted average, and the most recent period has the most effect.

[Alice]

My endo told me that the test from blood that is drawn will always vary from the finger tip tests. She said both numbers are correct, just different blood sources. (Vein vs capillary?)

I had the finger-tip done within a few days of bloodwork...my fingertip was lower by about 4 points.

I think test will vary all the time anyway.

[belyro]

My endo told me that the test from blood that is drawn will always vary from the finger tip tests. She said both numbers are correct, just different blood sources. (Vein vs capillary?)

I had the finger-tip done within a few days of bloodwork...my fingertip was lower by about 4 points.

I think test will vary all the time anyway.

Ditto to this. My fingerstick test was lower by 4 points too.

[jeggeman31]

Thanks All

Well again I get hit with the "your message is to short" so I am typing this

[deansreef]

My A1C is 6.0 or less everytime In fact was only 6.1 one time and as low as 5.5. This is because of testing below 70 76 times out of 150 tests.

[tylerskillyness]

Hey, I'm new. my girlfriend today just tested 10... im so scared for her life. According to her mother you are doing well because anything under 6 is amazing so i hear.

[JJM335]

My endo told me that the test from blood that is drawn will always vary from the finger tip tests. She said both numbers are correct, just different blood sources. (Vein vs capillary?)


There are plenty of websites, books etc. that will quote tables correlating A1c and Mean Plasma Glucose (MPG). However these need to be interpreted with a bit of caution and it helps to understand the original published research on which these numbers are based.

This involved measuring A1c's for a large number of T1's and then measuring their MPG's. The first is relatively easy (although even here there are uncertainties, see below). To do the second ACCURATELY, you would need to hook all these T1's up to continuous monitoring over the 3 month period, or at least have them test 8+ times per day. In fact most T1D's won't do this, so instead, individuals were extensively monitored over 1 or 2 days out of a 3 month period. As any T1 knows, individual days can be far from typical!

Perhaps as a consequence of this, The data points (one for each individual T1) show a huge amount of scatter. To illustrate this I have pasted the actual figure from the key paper from which came the oft-quoted "fact" is that an A1c of 6.0 corresponds to a MPG of 7.6 (137). However, the 95% confidence interval is 3.8 mM. This says that you would expect 95% of individuals with an A1c of 6.0 to have a MPG of between 5.7 and 9.5 (or in US$ about 104 and 170). That's a huge difference.

A second difficulty is that the fingerstick and blood draw methods give different A1c numbers. The fingerstick values are on average 0.2 higher, so your numbers will appear to be WORSE using this method. To complicate things further the difference gets bigger the lower the numbers, as much as 0.5 for really good A1c values (in the 5's).

The A1c is a valuable indicator of control, and lower MPGs means less health problems. However, we should perhaps be careful when playing Liar's Poker with our A1c numbers!

My 2c


Joel