Debugging Unexpected Blood Sugar Highs

Every time I get things working, as far as balancing food and insulin, something changes and I get knocked back to square one. And, surprise, surprise, it has happened again.

Out of the blue, last week, I started seeing highs after meals using doses of insulin that up until then had matched specific food inputs perfectly. Over the week they've gotten worse until yesterday I spent most of the day well over 150 mg/dl and partly over 200, though I used more insulin yesterday than I've ever before used in one day.

I checked the Usual Suspects that I always consider when my blood sugar goes blooey on insulin, which I'll list here:

1. Meter problem: I tested highs on two different meters with strips from two batches and they matched within 4 mg/dl. No meter problem. (Of course, I washed my hands after seeing the first high, to make sure I didn't have sugary fingers.)

2. Insulin problem: Because I use very small doses of insulin, one vial or pen can last me a very long time. But over the past two years I've learned that any vial of insulin that gets used 3 times a day can deteriorate after six weeks, even if I've only used 100 units out of the 300 in the bottle. Sometimes I can see tiny crystals in the previously clear insulin. Sometimes I can't see anything, but replacing the vial or pen solves the problem of mysterious highs.

I replaced both my R and my Novolog pen with new ones. The problem did not go away.

3. Getting Sick? Sometimes we see rises in blood sugar days before we get sick.

I did end up developing a nasty viral outbreak in my mouth this past week, which is something I get from time to time. But I'm not sure that would be enough to cause the dramatic deterioration I'm seeing. I've had it before without seeing highs. And the outbreak is clearing up while the blood sugars are getting worse.

4. Carb Creep/Wrong Carb Insulin Ratio: Is that 30 grams of carbs really 60? Sometimes we get sloppy with our carb counting.

I thought that might be the problem, but yesterday I weighed portions and had a very good idea of what I was eating and saw crazy high numbers. More importantly, the timing of the highs was really strange--with the highest reading almost 3 hours after eating and injecting Novolog. When I did a Novolog correction at 3 hours, I ended up with a wicked low an hour later. This is NOT the usual pattern I see at all, but it does require further investigation.

5. A Change in Meds or Supplements: Any medication or supplement we take, whether for diabetes or not, can impact on our blood sugar.

In this case there were two obvious suspects. The high blood sugars started before I stopped taking Metformin again, and ideally I should have NOT stopped taking metformin when I developed highs, because my blood sugar will go up a bit without metformin, though not a lot. But I had no choice, as the Metformin was giving me continual burning stomach pain and I was also feeling very exhausted after taking it, which is something that had gone away when I stopped taking it before. So I decided that I had to stop taking it, because it was clearly not helping me out anymore.

But that said, I had stopped taking Metformin for several months only a few months ago without seeing dramatic highs. Usually I see a rise of about 10 mg/dl in fasting blood sugar and maybe of 20 mg/dl after eating when I am not taking Metformin. In the past, to correct for this I had only had to add another unit or so to my dose at meals, and 1.5 unit of NPH at night to knock down the fasting blood sugar. This was nothing like the 50-70 mg/dl rise I have been seeing this past week.

A I blogged earlier, I have also recently started taking 1000 IU of Vitamin E, which initially was causing lows which stopped after a week or so. Then after reading up about Vitamin E I added 2 Calcium/Magnesium supplement pills to my daily regimen, since it turns out that without available Cal/Mag Vitamin D may store metals in your bones. Hmmmmm. Needs further investigation!

6. Too Much Insulin Causing IR? It's one of the ironies of insulin use that if you use too much insulin the body may get into a counter-regulatory mode where surges fight and flight hormones push blood sugar up out of the low range and the body becomes more insulin resistant out of self-protection. I have always had a huge problem with unwanted counter-regulation in the past, which is characteristic of MODY-2, the kind of genetic diabetes I'm currently being tested for.

So this idea isn't so far fetched. When I figured out the right dose of Lantus to use to avoid hypos last year, I saw very high post-prandial numbers--and that was why I stopped the Lantus. I have been using increasing doses of NPH for the past month to try to get my always high fasting bg down and had added a unit or two every morning, too. Requires investigation.

7. Deteriorating Beta Cells: While this is not a likely explanation, we can't rule out that something may have caused my beta cells to shut down or otherwise misbehave. I don't think this is likely, because the last time I stopped using insulin (with a very low carb diet) my post-prandial control was a lot better than it had been 2 years ago when I started insulin, suggesting that beta cell rest had given me more function in my beta cells, not less.

Into Debugging Mode!

Since I come from a computer engineering background, I'm familiar with the techniques used to debug problems that develop in large, complex, poorly documented systems. So now it's time to sort out what might be causing these highs.

Key to doing this is the basic debugging concept: When there are multiple possible causes for a poorly understood problem, go back to something that works (if possible) and then change one thing at a time and see if you can reproduce the problem. Start with the most likely and work back to the least likely.

So here's what I'm gong to do:

1. Cut out everything that looks like it might be causing the problem: the Vitamin E/Cal/Mag supplementation, carbs, and NPH. I can do this because I am fortunate to still have some natural insulin production left. A Type 1 could not cut out a basal insulin, because cutting out the basal could make them very, very sick.

2. Cut carbs way, way down and stick to foods where I'm certain about the carb count. My most recent stint of low carbing wasn't that long ago. I was able to stay between 95-120 most of the time if I kept my carbs under 12 grams per meal and 6 at breakfast, a la Bernstein diabetes diet. I have some other problems that this diet makes worse, but for now I'm going to eat that way to get to an acceptable baseline. It mostly eliminates the problems caused by mismatching insulin to meals.

3. Add back one suspicious element at a time to see if I can determine what is causing the problem. Here's my thinking:

a. Add nighttime NPH. I started using NPH at night when I was off Metformin before because without Metformin my fasting blood sugar is always around 100 or more. It did not seem to cause a rise in my day time blood sugars. Because my fasting bg on a Bernstein diet will quickly go up to 110-120 mg/dl I want to address the high fasting value first before doing anything else.

If after doing this I don't see daytime highs:

b. Raise the number of carbs I eat in each meal gradually using my old reliable R insulin and my usual Non-Met carb/insulin ratio (1:10-1:12). Use measured portions of foods I'm familiar with. This should quickly tell me if using the wrong carb/insulin ratio was the problem.

If this solves the problem of daytime highs:

c. Add back the Vitamin D and Calcium/Magnesium.

If this doesn't cause daytime highs:

d. Add back the morning NPH dose.

Obviously, if one of these elements DOES cause the daytime highs, I'll have to stop using it.

I should wait a couple days before introducing each element.

Obviously, this is all a pain in the neck, but when I'm done, I should have a better idea of what is going on. I hope! If the problem was that I'm really about to come down with a cold, I might add everything back in and not reproduce the problem, but that works too.

Any other debugging suggestions from you folks who live with this crap day in and day out?