Wednesday 19th October 2011

The last couple of days have been an examples of the “quirks” that diabetes can throw into the mix, just to make things that little more complicated!

In my last post (or maybe the one before?!) I said that exercise lowers blood sugars. Now, this is the theory! Aside from a known exception this is the effect exercise SHOULD have on the blood sugar levels. Unfortunately, my body doesn’t seem to be aware of this! I’ll explain from the beginning, but before I do I will explain a little about how insulin works and the effects of exercise… In the words on Jennifer Aniston, “Here’s the science bit, concentrate!”

We eat food to give us energy and in our bodies that food is broken down into glucose. Glucose gives our cells the energy they need to function. But in order for our cells to utilize the glucose they need insulin: insulin acts as the key to allow glucose into the cells, without it the glucose floats around in the blood system doing all sorts of damage to the body’s organs.

As a diabetic, I need to give my body just the right amount of insulin to let the glucose into my cells; your bodies cleverly do this for you to an amazing level of precision. When the glucose can’t get into the cells a diabetic will feel lethargic and, if left untreated will start to lose weight rapidly as the body tries to get energy from whatever sources it can, beginning with the fat surrounding more muscles, before eating away at your muscles and eventually the organs themselves. The levels of glucose in the blood will rise to a dangerous level, generating ketones (which are a by-product of your body burning its own fat) and can eventually lead to a coma. When I was diagnosed I was very close to being comatose. My BG was 44.4; incredibly high!

But that’s an aside… A diabetic should only exercise when their BG levels are near to ‘normal’. This is because when you exercise, your cells use up energy. In order for the glucose in your blood there needs to be enough insulin in your body to allow the glucose into your cells. If a diabetic exercises when they do not have enough insulin to take the energy from the glucose available, the body begins to use the fat stores for energy, not a problem in itself for this short period, but it results in the BG levels rising instead of falling. A bit complex, and to be honest I think it does my good to write all of this down again; it’s easy to forget!

So now onto the last couple of days:

On Monday night, as I said I would, I tested my BG before bed, during the night (at around half 3 when a motor cyclist decided to do laps around our apartment building) and in the morning. This is what I found: before bed on Monday my BG was 269 (14.9), far too high so I corrected by giving myself 1.5 units of RAI. On waking I was 170 (9.4), still a little high but roughly consistent with my 3am test, which was 138 (7.6). I have converted into mmol/L because I still find it easier to analyse them in this format.

Given that I think my correction factor is 3mmol/L for every unit of insulin, giving myself 1.5 units of insulin with a BG level of 14.9 should mean that my BG levels stabilise at around 10.5. Mine went down to 7.6, which is a little lower than I would have anticipated. This, on its own, may mean my correction factor is incorrect and that actually 1 unit of insulin lowers my BG by more than 3 mmol/L, or, because it was more than four hours since my RAI dose, it could mean that my overnight basal dose is too high. (Rapid Acting Insulin has a profile of around 4 hours and the basal insulin’s job is to keep my BGs stable without food or RAI, the two work together as the graph below shows:)

BUT then, on waking, my BG had gone UP again, by 2 mmol/L which, on its own, would suggest that my basal dose is not high enough. Together, I have no idea what to do with these two bits of contradicting information! I need to continue as I am doing, and hopefully some sort of pattern will come to light.

But it doesn’t stop there. Last night, when I got in from work I went to the gym. I tested before I went and I was 166, a perfectly acceptable level to go to the gym on. So I went, and afterwards I was 169. I ate dinner and gave myself my RAI according to my App, reducing it by two units to allow for the exercise, the effects of which can last up to 24 hours.  Before bed I was 202, a little high but again because of exercising I decided not to correct, thinking my BGs would fall over night. But when I woke up at half past two and tested I was 334! And I have no idea why… It could be to do with my basal dose not being right, but 132 is a massive rise, much bigger even than the previous night. My App told me to correct, so I did and I woke up with a BG of 155: much more respectable but still a little higher than I ought to be.

So basically, as it stands, I’m a little stumped. I am going to try and repeat my tests tonight and see what happens. The only way to know for sure is to build up data over a period of time. It’s just frustrating, especially at this point, when it doesn’t look like there is any rhyme or reason to any of it! Even just in the space of 2 days my App sstats have changed. My % of hypoes has gone down to 9% but my ketone warnings have increased from 0 to 2%. Although it’s easy to be sneaky and try not to test at the times which may result in unwanted readings! For the sake of this bog at least, I will try to be honest with myself.

I was just thinking too how, psychologically, the new units of measurement give me a larger window of acceptable blood sugars: in mmol/L the acceptable range is 4 – 7; in mg/dL the equivalent is 72 – 126! While I know that they are the same a margin of 54 seems much easier than one of 3!