9 June 2008
By Gina Kolata
Rein on sugar doesn’t cut diabetics’ mortality risk
The results provide more details and bolster findings reported in February, when one of the studies, by the National Institutes of Health, ended prematurely. At that time, researchers surprised diabetes experts with the announcement that study participants who were rigorously controlling their blood sugar actually had a higher death rate than those whose blood sugar control was less stringent.
Now the federal researchers are publishing detailed data from that study for the first time. Researchers in the second study, from Australia and involving participants from 20 countries, are also publishing their results on blood sugar and cardiovascular disease. That study did not find an increase in deaths, but neither did it find any protection from cardiovascular disease with rigorous blood sugar control.
Thus both studies failed to confirm a dearly held hypothesis that people with Type 2 diabetes could be protected from cardiovascular disease if they strictly controlled their blood sugar.
It was a hypothesis that seemed almost obvious. Cardiovascular disease accounts for 65 percent of deaths among people with Type 2 diabetes. And since diabetes is characterized by high levels of blood sugar, the hope was that if people with diabetes could just get their blood sugar as close to normal as possible, their cardiovascular disease rate would be nearly normal as well.
The two studies were presented Friday in San Francisco at the annual meeting of the American Diabetes Association and will be published next week in The New England Journal of Medicine. The Journal lifted its embargoes to coincide with the presentations at the meeting. A third study, similar but smaller, by the Department of Veterans Affairs, will be presented at the meeting on Sunday.
Diabetes researchers say that the message is that patients should obtain at least moderate control of blood sugar to protect against eye, kidney and nerve disease.
But for heart disease, they say, the only proven method of preventing complications is to give statins to control cholesterol, drugs to control blood pressure and aspirin to control blood clotting, and encourage people to lose weight and exercise.