Targeting Normal Values for Blood Glucose and A1C
I recently received an interesting question (which I paraphrase below):
Nondiabetics' mean blood sugar level is around 83 mg/dl, whereas our teachers and the ADA recommend keeping it between 80 to 120 mg/dl. This is allowing patients to leave it >30% higher than where they could have been with better control.
Is this not the reason of having a lot of vascular and neurological complications?
Are the advisors giving loose and harmful advice?
Is there a way to have a real fact and clinical study to base the advice for the benefit of people afflicted with diabetes?
The concern about targeting normal values for blood glucose and A1C in people with diabetes has always been the issue of provoking hypoglycemia if aiming for normal values.
Recently, there's been an additional concern identified when aiming for perfection: In patients with T2DM plus cardiovascular disease (or cardiovascular risk), aiming for lower values of A1C (below 6) increased the risk of death compared to aiming for higher values (between 7 & 8). See ACCORD and ADVANCE again. This result was absolutely surprising, and is still unclear as to why aiming for normal A1C would increase the risk of dying. The deaths weren't from hypoglycemia, BTW.
In a few very highly-motivated and very well-educated people, it is indeed reasonable to aim for normal values of BG and A1C -- if they are willing to do zillions of BG tests, and are willing to put up with the potential of severe hypoglycemia.
But I don't think the average person is that motivated, nor that educated. So the goals for the general population with diabetes will be somewhat higher than perfection - to avoid the risks of hypoglycemia and the possible risk of increased death.