wellness tips

Diabetes study partially halted due to deaths

March 1, 2008 at 6:24 pm · Filed under Health Issues

I promised a couple of weeks ago to comment on the ACCORD type 2 diabetes study, part of which was halted due to increased deaths in the arm of the study that was trying to aggressively lower blood-sugar levels to those of non-diabetics. This result was surprising to many, as it was widely expected that very low blood-sugar levels would improve health outcomes rather than increase risk of death.

The ACCORD trial (ACCORD stands for Action to Control Cardiovascular Risk in Diabetes) was launched in 2001, and involved over 10,000 people from the US and Canada that had suffered from Type 2 Diabetes for at least 10 years, and were at high risk for heart disease. One of the questions asked by the study was whether or not lowering blood-glucose (sugar) aggressively was more effective than lowering it less aggressively, using hemoglobin A1c as the measure. One group was asked to try and maintain an HbA1c reading of less than 6%, and another group, between 7 and 7.9%, which is the current diabetic treatment goal. Hemoglobin A1c is a useful measure because it can tell a physician how well blood-sugar levels have been controlled over a period of weeks. There were 20% more deaths in the group that were asked to maintain a hbA1c of 6%, and as such, that part of the study was halted.

So, what might explain these surprising results? I think it is important to remember that Type 2 Diabetes is not only a disease of high blood-sugar and of triglycerides being inappropriately deposited in muscle and liver cells, but also
a disease of high blood insulin levels due to insulin resistance. Insulin is damaging to arteries, and paving the way for heart disease. Those in the “aggressive” arm of the study were asked to lower blood-sugar to very low levels, and many used insulin and insulin pumps to be successful at that task. Type 2 Diabetics by definition have high insulin levels, and to achieve the goals of the study, some were taking more. I think that it is very plausible that very high insulin levels may have accelerated the cardiovascular disease, possibly prompting more deaths. Not only that, but we also know that high insulin levels promote the conversion of carbohydrates into triglycerides in the liver, further increasing insulin resistance and obesity. In my opinion, treating Type 2 Diabetes with insulin would make the whole cycle worse.

In the next few weeks I want to look more closely at obesity, heart disease, and diabetes as I am becoming more and more convinced that these are different manifestations all coming from a similar cause.

National Heart Lung and Blood Institute Questions and Answers
Action to Control Cardiovascular Risk in Diabetes (ACCORD) Trial Feb. 6, 2008.

ACCORD February 6, 2008, ACCORD Study Announcement

Helen Branswell Death halts part of diabetes study The Star.Com Feb 06, 2008.

Gina Kolata Diabetes Study Partially Halted After Deaths New York Times, February 7, 2008.

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