There is always a lot of talk about A1C on this forum so I thought this article may interest some
A1c is just an average and it really tells you a blurred reality.
I used to do a1c testing in the lab and there are a lot of variables.
Firstly the test is actually testing glaciated hemoglobin.
For those of you who don’t know that term, it is the red stuff in your red blood cells.
When hemoglobin sits in sugar a portion of it becomes glycated. That’s just fancy for sugar bound to hemaglobin. This happens when a cell is first created and is locked in for its life.
So a red blood cell lives for 3 months. That’s how they get a average for your control over 3 months.
There is really no direct correlation to average sugars really.
Red blood cells are created at night more than day so your a1c is much more heavily effected by night sugars than daytime.
Also being dehydrated makes it higher. And your blood sugar at the time of the test will effect it too.
I did this myself. I went to work and tested myself at 6.6. My fasting sugar was 81. Then I ate lunch and purposely allowed myself to hit 190. I retested and my a1c was 7.1.
So what I’m sayin is. Go to the blood draw with stable sugar and make sure you drink a lot of water before.
Tighten up your night sugars.
But really it is only a rule of thumb.
When I was first diagnosed with Type II, I also found out I was severely anemic. The doctor said my hemoglobin was so low at 6.2 (normal is about 13-15) that the A1c test wasn’t accurate. Although it was high enough at 11.2 that she was certain I had diabetes and treated me for it. So yes, various factors can definitely influence the results.
That’s true. If your hgb is low then your aid will be lower because the test assumes you have an average hgb. Men are almost higher than women so a mans a1c is a little lower than a woman’s with the same glucose control.
In reality we need to use it as a rule of thumb.
If you make your own calculation it can help.
So if you have cgm and looks at 3 month average you will get say 120. If you are getting an a1c of 5.8 then you are pretty average. If there is a discrepancy then just know that going forward.
There is a lot of variation between individuals. AGP reports use a different equation, and give a different answer.
My targets and measure of control is TIR. Current endos are on board with TIR, but HbA1C is still run to keep them happy. My HbA1C is OK for comparing months long time periods, but is otherwise more of a curiosity.