A couple of years ago, it was reported that intensive treatment of type 2 diabetes, aiming for a hemoglobin A1c level below 6, increased cardiovascular events compared with patients aiming for an A1c between 7 and 7.9. The study was called ACCORD, and the glucose arm of the study was stopped early because of the excess deaths in the intensive-treatment group.
On the basis of this one study, a lot of doctors told their diabetes patients who had A1c values in the normal ranges that they were too low and they should attempt to get them higher!
They seemed to apply this advice to everyone with type 2, even though the patients in the ACCORD study were older (between 40 and 79 years), had had diabetes for a median of 10 years, and already had signs of heart disease or had several risk factors for heart disease.
I've previously discussed the ACCORD trial here, here, and here.
A conservative interpretation of the study was that aiming for a normal A1c might be harmful in older people with longstanding type 2 and pre-existing signs of or risk factors for cardiovascular disese but it would be OK for younger people who had recently been diagnosed. The idea was that if damage from high blood glucose levels has already been done, it may be too late to help by getting those levels down.
Another interpretation was that these people had been put on traditional high-carbohydrate American Diabetes Association diets, so they needed a lot of drugs to get their A1cs in normal ranges, and it was the combination of so many drugs that caused the increased cardiac events.
Another interpretation was that they'd brought the A1cs down too quickly, and that was what caused the harm.
And another was that the intensive-control group had more serious incidents of hypoglycemia.
Now comes a new interpretation of this study that says that those who were actually able to reach the normal A1c goals had lower rates of cardiovascular events. It was the patients who were unable to reach the goals despite the intensive treatment who had increased rates of cardiovascular events.
Mortality was greater in the intensive-treatment group only when the A1c was above 7.
The new interpretation was published in the May 2010 issue of Diabetes Care.
None of the mainstream analyses of the ACCORD study have suggested that instead of intensive treatment with drugs, patients might benefit by using lower-carb diets to get their A1c levels down. We know that works. Why can't the cardiologists understand it?
I think one thing the back-and-forth recommendations resulting from the ACCORD trial tell us is that we shouldn't forget to use common sense. If we're discussing treatment of a mentally compromised relative who is 99 and unable to understand why he shouldn't eat huge dishes of ice cream and chocolate sauce, perhaps trying to enforce a low-carb diet so the poor man would have no enjoyment in life wouldn't make sense.
One vision that haunts me is the description of an old diabetic woman in a nursing home. Everyone else got ice cream for dessert, and the nurses said, "You can't have ice cream because you are diabetic." The old woman cried all during dessert because she wanted the ice cream so much. That's cruel. Especially because they were probably stuffing her with starches like bread and potatoes.
But if we're still pretty healthy and able to manage our diabetes diet ourselves, and if we understand how harmful high blood glucose levels can be, we should make an effort to get the best A1c levels we can manage, even if some study shows that this might be harmful to some people.
We shouldn't reverse our treatment plan on the basis of one study, which is what the doctors who told all their type 2 patients to get their A1cs higher did. One study doesn't prove much. The study might have been poorly designed. The population studied might not be representative of the population as a whole, or it might not match your own situation (a study of 80-year-old male veterans might not apply to a 40-year old woman). The statistics used might have been faulty. The treatment in the study might have been different from what you are using.
There are many reasons that one study might be misleading. It's only consistent results that are significant. We shouldn't totally ignore any study. But we need to take them with a grain of salt.