Also known as the HbA1c, hemoglobin A1c, or Glycosylated (or glycated) hemoglobin test.  This is a blood test that measures the average blood glucose levels over the past 2-3 months.  Glucose can bind to the hemoglobin which is found in the red blood cells.  This causes some sort of modification of the molecule in the blood cell which is I guess what is measured, in a percentage. What is important to understand about this number is that it is an average.  Meaning if your blood sugar is fairly stable you could get a certain resulting number, but you could also get the same exact number if you have a lot of highs and a lot of lows.  Overall, this test is used to predict if you are in good control of your diabetes or not.  A normal number could tell you that you are in good control, but a high number definitely says you are not in control and are at a much higher risk of horrible complications that are much worse than just dealing with the daily annoyances of diabetes alone.  Anytime you have bad highs it increases those risks, which is why I think the A1c test is kind of tricky.

side note: I have wondered since the extra glucose messes up the red blood cells, I wonder if it affects how oxygen, and how much of it, is carried through the blood stream (since it is also carried by the hemoglobin) which is kind of an issue for some of us cystics with messed up lungs.  I’m going to look more into that someday. But if I find that is true I am going to get even more pissed at the CF docs who put off CFRD testing (not mine luckily). *sigh*

Apparently a “normal” person would have an A1c level at about 5.0%.  My doctors suggest an A1c of 6.5% or a little lower, normal would be ideal, but that is darned hard to reach.  My docs find that above 6.5% it seems to really affect the CF lungs.  To me I really couldn’t understand what that number meant until I found a calculator online that could translate the number into something I was familiar seeing on my little meter tester thingy I use every day.  Here’s one I like, it goes both ways from A1c% to mg/dl.
http://www.accu-chek.com/us/rewrite/content/en_US/4.1.2:20/article/ACCM_general_article_2422.htm
Here’s a little chart on dLife:
http://www.dlife.com/dLife/do/ShowContent/blood_sugar_management/testing/a1c_conversion.html

154 mg/dl is the magic average number.  Personally, what I try to do is make sure I am at a safe, but lower number (preferably 85-95) through out the night since I am spending 8-9 hours at that level.  Recently with my Continuous Monitor I have found I am having a strange spike at 2:30-3am which means I am going to need to change my basal insulin rate at that time… but that is a whole different story.

Once last year I scored a 6.0% on my A1c test (yes, it went on the refrigerator)… I really doubt I am there again, it took a lot of hard work and discipline, but here is some tricks of how I did it…  Having a lower level for many hours while I am asleep made it easier to get to my goal A1c level.  When I spike at meals, I try to keep it under 200 mg/dl at the two hour mark by counting my carb intake as close as I can (IMPOSSIBLE when on evil evil prednisone), but I make corrections at the 2 hour mark if I have to (my pump figures out the calculation taking in consideration how much active insulin I already have in my system, which is why I am such an advocate of the pump, it does all the brainpower).  I have played with my numbers and found at my of 1 unit of insulin (which is an unbelievably small amount, it’s like a few drops!) for every 8 grams of carbs and my correction or sensitivity rate of 1 unit to 25 mg/dl (how much my bg number will drop with one unit of insulin), If I miss calculate my carb intake by 20 (two macroon cookies, who ever eats just two cookies?!) my blood sugar level will go up 62.5 points (mg/dl). HOLY!  That means I need to keep quite a close eye on things.  It never used to be that way when I was on shots, I was on a 1:15 ratio…. but then again, I was never in control of things on shots.

Back when I was out of control, my A1c level (at least the first one I really paid attention to) was 9.3%.  That number alone wasn’t enough to scare me.  But it should have.  The toll it took on my poor body was too much for it to handle and I have not escaped a few complications.  Nothing too scary, but annoying enough to get put on a few extra medications.  I wish I would have known then what I know now.