Blood tests

Why The HbA1c Sucks

So the other week I was thinking about the relevance of the a1c, how it is applied in a clinical setting and how we as people with diabetes are often judged by our clinicians and also our peers.

insulin pump

insulin pump

As technology gets more sophisticated such as pumps, cgms’s, software will have access to more data than we have ever had.

Traditionally the a1c is the benchmark that we refer too, we talk about it, we feel guilty about it when it is a higher number than we hoped for and feel pure elation when we get a magic number.

Now I don’t need to explain to many that our control can at times resemble something similar to a Manhattan whilst occasionally it will resemble something smoother, more controlled and it is the latter that we all strive for.

So what the heck are you going on about Mike? Well let’s put this simply. Using the a1c sucks as a measurement. It is next to useless as an informative evaluation tool. Why Mike?

Let’s take person A and person B. Both have a a1c of 7% and they both test their blood at least 4 times a day whilst following similar treatment plans.

So person A has many highs and many lows, so when combined and averaged out equals 7%. It may make person A tired more often, possibly with more complications, whilst possessing lack of confidence maintaining control, not generally not feeling quite as healthy as they would like to be.



Person B on the other hand, tends not to swing so low and keeps the highs at bay which again equates to 7%. The day-to-day deviation is less, which means a graph would resemble more like a subtle wave.

So with that my theory is that the A1c is fundamentally flawed. Everyone who has the same percentage will likely have very different control patterns if we were able to map it out.

So how do we go about measuring our control? Unfortunately I do not have that answer of the top of my head yet? Do we look to advance the A1c test? The technology behind it?

Or do we look for another test? Blood test with different markers? I don’t know if this is even possible. Did I mention that I do not have a degree in biomedical science. 🙂

How would you like to have diabetes measured? Perhaps more reliance on cgms’s? If that were an option.

Let me know what ideas you have? Do you agree with my reasoning as to why I feel the traditional a1c test is flawed?

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9 Responses to Why The HbA1c Sucks

  1. J.A. Neitzel March 25, 2011 at 11:06 pm #


    Interesting perspective. I don’t know whether I agree or disagree outright. That said, even though my A1Cs do give me a good idea of my progress or lack thereof, my doctor & both know that I have a bigger than ideal standard deviation in my BGs.

    So, in the end, I suppose my doctor & I (? maybe all of us ?) simply have to *_also_* consider the 90 days worth of BG values that feed my resulting A1C. Sure, I got a bit of a yo-yo effect.

    But I think knowing our A1Cs is probably better than not knowing them. Eh? Granted, they are just numbers. So, it’s up to us to put them into perspective in the grand scheme of things that affect our living w/ diabetes from day to day 🙂


    • mike March 28, 2011 at 10:58 am #

      Hi Jeff, I understand where you are coming from. Possibly for the main, if we have some information available then it will be better than none at all.

      It seems that at times our care is based on myths, uninformed clinicians and countless fairytales. 【ツ】


  2. Bernard Farrell March 28, 2011 at 1:29 am #

    Mike, some company contacted me that’s working on an A1C alternative called glycated albumin. I’ve not looked into it, but they claimed it gives better results than an A1c. For those of us with CGMs we have the advantage of looking at their reports to get an average and a standard deviation, showing how ‘tight’ that average is. Until CGMs are more universal I don’t think we’re going to come up with something better.

    • mike March 28, 2011 at 11:00 am #

      Hey Bernard.. That would be cool. Fingers crossed it could be developed.

      In terms of long term management, I guess you can’t go wrong with a CGM..

      Here’s to hope 【ツ】

  3. Tim March 28, 2011 at 10:43 am #

    You’re right Mike – A1C does suck. It completely misses a whole lot of revealing data and is a very crude way of finding out how an individual is doing with their diabetes. Though, as my mother said, if you don’t have anything better to suggest then be quiet. So I’m going to be quiet.

    • mike March 28, 2011 at 11:02 am #

      I agree, as I have very little to contribute to biomedical services except my blood..

      Back to the drawing board.. 😉

  4. Scott K. Johnson April 17, 2011 at 8:44 pm #

    I have no bright ideas to contribute, just wanted to say that I also agree. I hate how we are measured by our peers even more so than by the medical professionals.

    I also think that it’s better to have it (the A1C) than nothing at all, right?

  5. Adienne April 18, 2011 at 12:19 am #

    I agree, A1c is better than nothing. I think that if you get your result you just need to be aware if it is a good one. ie if you are person A or person B. Person B clearly has a good result with his A1c of 7% but person A who also has 7% but swings, can really take no notice of his result as it is just a measure of swings really. Person A would be better with a result of 8% but with no swings and can work from there to bring it down to a good 7%.
    No idea if that was waffle or if it make sense.
    I also agree you can’t go wrong with a CGM which is what my daughter has and we wouldn’t be without it.

    Pumps & CGM for all I reckon 🙂


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