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Morning BG Profile

R

Robbins

Member
Messages
20
Type of diabetes
Type 1
Hi, not new to the Forum, but new to MDI and posting on the Forum.

I have a query, which I guess is pretty basic knowledge, but can’t quite get my head around?


I have been testing again this morning to try and work out my profile from breakfast (8:00) to Lunch (13:00).


At the 2 hour mark after breakfast (10:00) my BG has risen 2mmol.

At 11:00 it has dropped 1mmol from the 10:00 reading.

At 12:00 is has dropped another 1mmol since 11:00, so now I’m effectively back to where I was at 8:00 a.m.

At 13:00 (Lunch) my reading is another 1mmol lower.


My questions are as follows:


  • Is a 2mmol spike after eating normal?

  • Is the above profile reasonably normal?

Now, all of the above seems absolutely fine to me, especially if you start the day at 5mmol, because you’re not getting above 7mmol, and not dropping below 4mmol

However, if you start the day at 8mmol as I did today, the figures read pretty rubbish.


So my last, and most important question really is, if I start the day at 8mmol, what can I actually do to get in range at all during the first 4 hours of the day?

I appreciate the answer is to get your waking levels to around 5mmol, but that’s easier said than done right?

Does taking the insulin earlier help this kind of profile?

I guess the obvious solution would be exercise, but not always convenient if you have to go to work?


Would be interested to hear some of your hack’s on the subject.


Cheers
 
Robbins said:
My questions are as follows:


  • Is a 2mmol spike after eating normal?

  • Is the above profile reasonably normal?
Click to expand...
The 2mmol spike is just what you want, and the above profile, returning you to the same level at four hours is exactly what you want. Dropping a further 1 mmol an hour later suggests that you may be running with too much basal insulin.

Starting the day at 8mmol when your target is 6mmol requires you to use a correction dose, which is based on your Insulin Sensitivity Factor. ISF is the number of mmol 1u will drop you. The "technical way" to get a start point for this is to use the rule of 100.

You divide 100 by your total daily insulin dose to get a result. This result is theoretically how much 1u of rapid acting insulin will reduce your blood glucose level in mmol/l.

If we assumed that your total daily dose is 45u (adding up all Rapid and Basal insulin), then your ISF according to this rule would be 100/45 = 2.2mmol.

Knowing this, you would then take you bg level before breakfast, work out how far it was from where you want to be, using the earlier example, 8 mmol/l is 2mmol/l too high. So you need to drop by 2mmol/l.

You know that 1u drops you 2.2mmol from the earlier calculation, so to get a 2 mmol drop you require 2/2.2 = 0.9u.

You would add this amount to the amount you have calculated for the carbs in your breakfast, the aim being to get your post breakfast level down to your target. If you aren't using a pump, you'd need to round a bit, and in that case, I would take 1u and expect to end up a little below the 6 target.

Bearing in mind that the Rule of 100 gives you a theoretical number, you might want to check, by experimenting and testing, that this number is correct. My Rule of 100 number is 2.4, but my reality is nearer 2.8, for example.
 
Thanks Tim, where I am confused is, I actually took additional insulin to correct the 8mmol (or so I thought).
I assumed that the additional 1mmol drop between the 4 and 5 hr mark was due to this additional amount of insulin, ie, the correction was happening at the end of its cycle.
So from what you say, that isnt the case, its probably not enough quick acting insulin, and my basal is too high?
How quickly normally would the correction dose work?

Cheers,
 
@Robbins, assuming you already bolus ahead of your food you could leave a longer duration (when 8mmol/l or above) between injecting and eating which may reduce the postprandial spike, in the book Think like a Pancreas the author goes into bolus timings when bg levels are on target, below or above your bg target range.
 
Hi Both, just wanted to say thanks for the above advice. Took my insulin 20 mins early, and tried my best to calculate the correction, so this morning looked like this:
8:00 8.1
10:00 7.6
11:00 7.3
12:00 7.5
13:00 6.6

Happy Days! Not perfect, but probably a PB as far as morning's go!
Will try and crack the afternoon's next week!

Cheers,
 
Looks a lot better @Robbins :)

Getting the bolus timing right can make such a huge difference.
 
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