11 Responses

  1. tmana
    tmana June 11, 2008 at 10:27 am | | Reply

    I would think a linear relationship would only be accurate if the test subjects were wearing CGMs and the results compared to CGM output as calibrated by fingertip testing, since that would be the best way to reliably catch the postprandial peaks most likely to cause hemoglobin to become glycosylated…

    One concern I have is the transition from the old test to the new test, because “…the new test results in a “normal range” for A1C that is 1.5 to 2% lower than the range everyone has become used to. For instance, what we call a 7% A1C would be reported as a 5% A1C with the new standard.” (

    This is likely to put a false sense of success and security on PWDs whose therapy is not bringing them within the standards of care — as well as an initial lassitude on the part of health care professionals who have not been clued into the new ranges, once their labs start coming back with the new numbers.

  2. mollyjade
    mollyjade June 11, 2008 at 2:03 pm | | Reply

    My doctors have always done this. “Your a1c is X, which is about equivalent to a blood glucose reading of Y.” That’s all they’re doing here, right? It’s just a change in the units, not a change in the chemistry of the test they’re running?

  3. Scott
    Scott June 11, 2008 at 4:36 pm | | Reply

    Another case of too many geeks coming up with a perfectly viable and useful test, but then not having ANY understanding of how to interface with the end users.

    It would be like saying, “wow, running that marathon took a long time, almost 408.7 dumbunits….” instead of saying 4 hours or whatever…Yes, we could measure time in dumbunits, and the ADA (American Dumbunit Association) could invent a nice little red calculator to convert dumbunits into hours and minutes…but what type of dingbat would even think of NOT using the standard measure…

    Sorry, personal peeve, I have to deal every day with technically intelligent people who couldn’t scrap up an ounce of common sense to save their lives…


  4. simone
    simone June 12, 2008 at 3:45 am | | Reply

    I think that many diabetics do not know what an hba1c actually is.
    It is not the soluble sugar that is running around in our veins . It is the haemoglobin which has become glycated ie a sugar molecule has attached itself to a particular haemoglobin.We actually have various forms of haemoglobin for example hba1b, hba1a1 and hba1a2.
    If a diabetic has an hba1c of 7% I think it means that 7 per cent of his hba1c has become glycated. I personally do not agree to give it the same value of glucose measurments (either mmol/l or mg/dl ) because we are basically measuring a different substance.

  5. Russell Scott
    Russell Scott June 12, 2008 at 6:27 am | | Reply

    If you can translate your A1C to the eAC how can it be more accurate?

  6. kevin
    kevin June 12, 2008 at 10:04 am | | Reply

    How much money has been spent on this so far and how much will be spent going forward? Also, how much of this money is actually our money (federal grant dollars, donations, etc…? And is this the best use of a finite resource – cash? I’m not saying yes or no to this since it’s just a number and an additional calculation (that we already deliver to patients as a mean blood glucose plus the A1c) so it’s not a big deal to change the math.

    There should always be a business case made when something like this comes up and cost is a real consideration when there are so many other things we can spend money on to improve diabetes care.

  7. David Edelman
    David Edelman June 12, 2008 at 10:13 am | | Reply

    Amy, thanks for posting this. I think people should also be aware that you can’t directly compare HbA1cs between people. Some people run higher or lower in their A1cs. I’ve been doing a number of researcher interviewers and a few have mentioned that two people with similar control can have A1cs that differ by as much as a full point.

    This is why some people with A1cs of around 6.0 can have complications much soon than you would guess. They may simply be running higher than the A1c suggests. If we’re going to use A1c as a marker, I think it’s important to note that it may not translate to your average glucose very well.

  8. DL
    DL June 12, 2008 at 10:43 am | | Reply

    Diabetes is all about change. You change your basals, your bolus, injection site, type of meds. Your numbers continually change, as do your emotions, hormones, stress, physical activity levels. The idea of changing from A1C to eAG shouldn’t be that hard to handle..and it’s about helping people relate the average 3 months numbers to something they understand (the numbers they hopefully see daily or multiple times daily).

    Yes, the general public and uneducated PWDs may see this as another change, but that’s the glories of new research and our wonderful experts out there. Just think, over two decades ago insurance companies didn’t want to cover home BG meters because they didn’t think it was necessary (similar to the CGM reimbursement debate today). I think referencing the eAG will make PWD work harder to adjust their regimens so they will see results they understand immediately (not just “this A1C means you are at higher risk for complications”)

  9. camille johnson
    camille johnson June 13, 2008 at 10:49 am | | Reply

    I’ll bet there’s money, and lots of it, to be made in the switch.

    Diabetes has to be one of TOP financial cows in all of medical-land. [I'm still trying to figure out shy insulin doesn't have a generic by now. And don't even get me started on sticks!] They’ve got us pegges as suckers because we are so desparate for better care. This may well be just one more gimmick.

  10. Tom Ross
    Tom Ross June 23, 2008 at 2:02 am | | Reply

    I think the relationship between glucose tests and A1c tests is being turned on its head here. We don’t take an A1c test to figure out what our average glucose has been lately, any more than we climb on a bathroom scale to figure out what our average calorie intake has been.

    The reason we care how sugary our blood has been lately is that sugary blood promotes glycation (bonding of sugar onto proteins), and glycation promotes degenerative disease.

    What we really need to be concerned about is how much glycation has been going on in us lately, and the A1c test measures that directly, so A1c is the real measure of how we’re doing. Glucose monitoring is just a means to an end; it’s useful to the extent that it helps us in our effort to reduce glycation.

    If we turn the thing around, and pretend that the A1c is just a means to an end, a tool for estimating average glucose, we’re confusing the issue (and distracting patients from what they should be focused on).

    If a lot of patients don’t get what the A1c test is about, I doubt it’s because the subject hasn’t been sufficiently dumbed down for them. More likely it has been dumbed down too much. People who set out to dumb anything down never seem to end up making it clearer — they just make it seem vague, boring, and unimportant. Anyone taking an A1c test should be given a leaflet that explains what the test measures and why it’s an important thing to measure. It wouldn’t have to be a very long leaflet; the issue really isn’t all that complicated.

  11. JuST Jen
    JuST Jen August 5, 2008 at 1:11 pm | | Reply

    Hemoglobin A1C actually IS a change in the chemistry, both in the molecule being measured and in the method used to detect the molecule. Hemoglobin A1C, as some others have pointed out, is a measure of how much hemoglobin is glycated (the standardized term for glycosolated or glycolyzed). Glycated means that glucose has associated with some of the hemoglobin in your red blood cells. The more glucose you have in the liquid portion of your blood (called plasma), the more opportunity for your hemoglobin to become glycated.

    All diabetics know that a high glucose level is bad for you. But, no matter how often you measure your glucose level throughout the day, you can not know how high or low your glucose actually was when you weren’t measuring it. Certainly, if you measure only your fasting glucose, you could get a very false sense of security. So, it may have been a little high in the morning—so what!! Here’s what—if it is high in the morning, it was likely very high at night (after you had that piece of pie when nobody was looking). If you are really good, you may even measure 2 or 3 times a day. You will likely still not catch your peak glucose level in one of those measures, so will not really know how well you are doing.

    Well, maybe you say you know how you are doing because of how you feel, right? Actually, you will probably only know when you are at an extreme level, or when it is too late to correct a severe problem. One example of this is the nerve damage that is often associated with diabetes, called diabetic neuropathy. This can cause your feet to always feel like ice, no matter what you do, cause unhalting pain in the feet or hands, eventually numbness. This doesn’t sound so bad until you have to live with it day in and day out.

    Then, along comes the hemogolobin A1C test. A1C is not cleared quickly from your blood stream like glucose can be. Once the hemoglobin is glycated, it will remain until after the blood cells die and even longer while the released hemoglobin is being cleared from your body. Because of this, the test is a better measure of glycemic control; i.e., whether your plasma glucose level is generally at a good level. This is overall what will determine the detrimental effects of glucose on your body, such as diabetic neuropathy. Your doctor may try to equate this to an average glucose level for you, just to help you understand what the test means. In those terms, A1C is a measure of how well you have controlled your glucose level over that past 3 months or so.

    Does this mean you should stop monitoring your glucose and have just the A1C test done? Absolutely not. You still need to know what your glucose level is NOW in order to make adjustments NOW that can affect your A1C going forward.

    How often you should have this test done depends upon how well you are currently controlled.

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