Sunday, April 29, 2012

Pet Peeve

Nope, it's not dumb comments from strangers who don't have diabetes. Not dumb comments from family that doesn't have diabetes. Not dumb comments from people with type 2 diabetes. It's people with type 1 diabetes.

And it's not when people assume that their diabetes management scheme is the best or the one I'm using (how often do I have to hear about pumps?!) And it's not when people assume that I want to give money to their cause (no thank you) or that I support it, whatever it is. Or when they make some unsupported blanket statement such as "type 1 diabetes is on the rise" or "the A1c measures average glucose".

Nope, the people who get to me are ones who think diabetes is easy to manage, and that complications happen to the unworthy, to those who just didn't put in the effort.

My diabetes management has been hard. I mean it. My Dexcom data currently shows that the time of day for which I have the greatest glucose variability, and the highest average sensor glucose is..... 4 AM.  Yeah- the time of day when I haven't eaten in many hours, I'm not exercising (I'm pretty much always asleep in bed at 4 AM), and you would think there are no variables. But no. At 4 AM, the standard deviation on my blood sugar is twice what it will be at noon. Wanna know why? It's because, at 4 AM (right before I typically wake up and eat or inject before going back to sleep) is when I am least likely to have checked my blood sugar in the previous three hours.
When I went on the Guardian, my first CGM, in 2008, I thought the overnight data was gonna be really useful in adjusting my Lantus dose. I'd know, in the mornings, whether my highs had been rebounds from low or what. Unfortunately, what I found was that almost every single night, my blood sugar was both low and high. It could go low and then high, or it could just as easily go high and then low. The variability was much greater than I had suspected. So I relaxed on my target for morning blood sugar numbers- no point in aiming for a blood sugar below 120 at wake up if most nights my blood sugar has been both 60 above and below what I wake up with.
These days my night time blood sugar shifts directions less frequently and often moves more slowly, but it is still difficult to figure out.
My blood sugar average is lower than the average for a type 1 adult, and so is my daily range. I have more hypoglycemia, and less hyperglycemia than the average. I have a lot of volatility to my numbers. The absolute value of the first derivative of my blood sugar in terms of mg/dl per minute is usually about 3.

Putting my own blood sugar difficulties aside for a moment, I find it instructive to look at why 7% was chosen as the target A1c. It's because that was the average A1c in the intervention group in the DCCT, the group that had lowered risk of complication and death, and the goal A1c they used was 6%.  That means roughly half of them didn't make it down to 7% despite intensive work at diabetes control. Furthermore, after the study ended, despite what they knew, the average A1c in the intervention group rose to 8.7%. If it had been easy to keep it at 7.0%, it would've stayed there.
That's my first point.

My second point is on the usefulness of diabetes control. I am not going to argue with anybody who says that somebody who has repeat episodes of DKA is doing a bad job of diabetes management (unless maybe it's euglycemic DKA). I am also not going to argue with anybody who says that on average, people with pretty much any measure of diabetes control take longer to develop complications and develop fewer complications overall. I have a big argument ready for anybody who claims that a level of diabetes control sufficient to prevent all serious complications is easily doable for everybody.
In study after study that I have read on various complications, A1c has been one of the more minor risk factors for developing the complication. Some of this isn't all that convincing because the average A1c in the diabetes group has been above 8% or even 9%, and the A1c is not really a great measure of average blood sugar or blood sugar control (see this recent article). But what to make of studies like this, where the average A1c is 7% but the rate of complications is more than half? Or that when I went to look at A1cs in diabetics getting vitrectomies, all of the studies I found included patients with A1cs below 6%? Depending on the complication and duration of diabetes, it's not hard to find prevalence studies on type 1 diabetics showing complication rates in excess of 80 or even 90 percent.
Joslin medalists aren't in that group, with overall fairly low complication rates after 50 years of diabetes. Their average A1c is above 7% now. The correlation among the Joslin medalists between their current A1c and retinopathy is nonexistant (same average A1c between those with and without retinopathy). Same for neuropathy. The correlation among Joslin medalists between A1c and nephropathy didn't reach the level of statistical significance, but I'm willing to say it exists (average A1c in those with nephropathy was 0.3% higher). Heart disease also showed a correlation that didn't reach the level of statistical significance but that also probably exists.
That means that the average A1c in a group of diabetics that made it more than 50 years on insulin was over 7% now, when their A1cs are probably lower than they have been for most of the last 50 years, if advances in diabetes care have made any differences in their lives. At an average of 7.2%, it is lower than the average for most diabetes cohorts I've seen. The two complications that really didn't correlate with A1c were the most common ones (eye and nerve disease). The two complications that almost correlated with A1c were the more dangerous two (heart and kidney disease). See Data Here

It is very possible for any type 1 diabetic to ignore their diabetes or otherwise mismanage their diabetes such that they will be able to cause their own premature deaths, possibly with diabetes complications on the way. It is not currently possible for all type 1 diabetics to prevent their own deaths from diabetes complications nor their development of diabetes complications.

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