Tuesday, June 22, 2010

I Guess This Is What My High School Math Teacher Was Talking About.

As a diabetic, and especially as a T1, my life is ruled by math - but really, just numbers in general. Keeping track of everything (glucose readings, insulin doses, food consumed, exercise, stress, etc.) was extremely overwhelming before I had an insulin pump and CGM to help record and remind me of some of my numbers.  I am also lucky, in that the "math" part of my health care can usually be done by my insulin pump.  However, in those rare moments that a pump malfunctions, I need to know the equations necessary to keep my insulin doses in check. 

In the diabetes world, numbers are often viewed as a gauge of how well you've been taking care of yourself – except, are they? Here’s a look at the D-numbers that make an appearance in my daily life.
  1. 15 to 25 – the amount of blood tests (pricking my finger) I do each day
  2. 13 – the number of different basal rates* I have throughout the day
  3. 1:5 – my insulin to carbohydrate ratio at lunch time (there are different ratios for other times of day)
  4. 15 – the minimum amount of minutes I need to wait between taking insulin for food, and actually getting to eat it
  5. 1:20 over 100 – the correction factor I use when figuring out how much insulin to take for a high glucose reading
  6. $732.56 - the amount of money Walgreens says my insurance saved me - on ONE MONTH'S worth of test strips
  7. 5 - the frequency, in minutes, that my CGM (continuous glucose monitor) checks my blood sugar
  8. 140 – my 30-day blood glucose average, according to my glucose meter
  9. 7.1 – my last A1C result
Some of these numbers have a lot going on in the background. Take number 5, for example – my correction factor. If I do a blood test and see 225, that’s definitely out of range (which, for me, I consider 80 – 120). But, I have to think about why I might be at that number – did I count the carbs exactly right in the food I ate? When WAS the last time I ate? Was I higher than this previously, and I’m actually mid-drop? Is my insulin pump actually delivering insulin, or did the cannula get clogged? Am I feeling especially stressed? All of these factors could have played a part.

Then, there’s the last item on the list – my A1C result from April. (The full name for the test is a Hemoglobin A1C test, which is a indication of your average blood glucose levels over the past 3-ish months. The recommended range is 4 – 7.  To put this in perspective, a 6 correlates to an average BG number of about 122.) I have been working very, very hard to bring my A1C down. Previous to this last test, I had pretty consistently come in at the 8 – 9 range. 7.1 was huge for me.

However, I can’t help but feel that A1C testing, in general, is flawed. So much rides on this one number. For most, it feels like a report card for “how well” you’ve done managing your diabetes, and is the benchmark for most of the medical community. Bad A1C?  You must not be working hard enough!

To some extent, this can be true - but not for every case, and not for every person.  An A1C result is only an average. This means that someone who consistently had a BG of 122, which mild or no fluctuation, has the same A1C result as someone who pings between 50 and 200 all the time – and the fluctuations are dangerous. 

The logical side of myself knows that the numbers are meant as tools to help – not as a measurement of whether I am a "good diabetic" or "bad diabetic". But, I often can’t bring myself to get past the feeling that they are just that - grades.  I want the numbers to reflect how hard I’m working, and they just don’t always do that. Some days feel like I’m fighting a war I can’t ever win. But, I just have to learn from the experience, and come out swinging - ready for the next battle.

*For those who are unfamiliar, a basal rate (not to be confused with "basil" - which would be much more delicious than insulin) is the rate of a continuous supply of insulin, provided by an insulin pump.  Different activities and times of day require different amounts of insulin, in order to maintain steady blood glucose levels.  What kinds of things can affect your blood glucose level?  That's for another day, and another post.  :)


  1. instead of sugar sticking our red blood cells, our effort should. then instead of our a1c being the average of our blood sugars, it would be the average of how much effort we put into managing our blood sugars. then my a1c would be much worse than it already it is. HA. maybe i'll stick with the way things are... :o) PS. i hate math too. it ruined my GPA in college.

  2. Is your insulin-to-carb ratio in No. 3 a typo at 1:5 at lunchtime? Mine is 1:15 at lunchtime, a pretty significant difference. Am I just ridiculously sensitive to insulin?

  3. Lisa - sadly, that is not a typo. My ratio really is 1:5. I've gotten more and more insulin resistant over time. I'm the odd one out, not you. :)

  4. Kim,our numbers are very close for most of your list. I am an insulin resistant T1 and my ratios are usually 1:4 at breakfast and 1:6 the rest of the day. This summer my ratio is 1:7 because I am having too many lows. I use less insulin in the summer.

    Sounds like some of the people here are not too pleased with math. Lol! I was a college math teacher for 34 years. Maybe I have wandered into the wrong neighborhood. Yikes!!! I better get outta here, fast! (See you on the Juvenation site, Kim.)


  5. Richard - Math teachers are welcome here too! (My sister-in-law counts among them!) :) Thanks for reading.


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