Is Tight Control of Diabetes Essential?

I’ve posted, several times, reports of studies showing how important it is to keep a tight control of your blood sugar, if you’re diabetic. Now a study posted online by the New England Journal of Medicine shows that aggressive glucose control in previously poorly-controlled type 2 diabetes did not lessen cardiovascular risk.

Almost 1,800 military veterans with an average age of 60 and poorly-controlled diabetes were randomly assigned to either intensive or standard glucose control treatment. If they had other cardiovascular risks, these were treated identically in both groups of patients.

At baseline, the HbA1c was, on average, 9.4%, showing how poorly controlled the subjects were. After 5.4 years the HbA1c was 8.4% in the standard treatment group, and 6.9% in the intensive–therapy group. Although the average HbA1c level was 1.5 percentage points lower in the intensive-treatment group than in the standard group by 6 months into the study, both groups had similar rates of major cardiovascular events (chiefly heart attack, stroke, heart failure, cardiac death) by the end of the follow-up period. Moreover, there were no significant differences between the two treatment groups with regard to microvascular complications of diabetes (e.g. kidney and eye changes).

This is the third study that has failed to show a drop in cardiovascular risk after intensive glucose control, according to the principal investigator. He speculates that earlier treatment in the course of diabetes, or a longer follow-up, might have altered the findings. The first link above refers to my report of a study that started early in after diagnosis and had a 10-year follow-up; the benefits of tight control were quite clear. As a diabetic myself, I’m a firm believer in pretty tight control (as long as it doesn’t interfere too much with your lifestyle!).