Friday, May 22, 2009

GLUCOSE CONTROL IN DIABETES. THE PENDULUM SWINGS AGAIN

Diabetologist and cardiologist differ in their approach to management of diabetics. This stems from the fact that diabetologists see patients with either no or multiple organ damage, and so use glucose levels as a means of judging effectiveness of diabetic control. They reason simply that insulin/sugar is the cause of the problem and so more insulin or less glucose should improve the problem. Cardiac boys on the other hand see diabetics with end organ ( in this case cardiac ) damage. They are more keen to see how treatment of diabetics can reduce end-organ damage. Lately (the last 5 years ) I see more diabetologist talking about major cardiac and cerebral vascular endpoints. This is good. We are almost singing from the same hymn sheet.
Except that now, when diabetologist try to recouncile glucose level control with end organ damage or effect, they end up with confusing results. And we are talking about large diabetic trials done by reknown workers. As a cardiologist, I watch from the side and try and draw conclusions.
On the one hand, we have the intensive control of glucose do harm people ( lets call them the "nay " people ) who feel that intensive glucose control may cause more deaths ( the ADVANCE Study ), or may make no difference ( the ACCORD and the VADT study ). On the other hand, there is the " yea " group who feels that intensive or good glucose control makes a difference in longterm cardiovascular mortality and morbidity ( UKPDS and PROACTIVE ).
In the recent May 23rd issue of Lancet, Dr Ray of Cambridge, did a meta-analysis ( a cheap way of doing a surrogate clinical trial ) on 33,000 patients with 160,000 patient years of followup, showed that intensive glucose level control, does reduce CV morbidity but not mortality, obviously at odds with ADVANCE. Interesting. But it is important to note that this is a meta-analysis, with all the flaws and shortcomings of a meta-analysis.
Whenever I am face with conflicting clinical data like this, I feel that the answer must lie somewhere in between as the individual patient is complex and we need to individualise therapy. It would appear that in some patients, I guess in those with recent onset diabetes, without end-organ involvement, intensive glucose control ( and here I think that the agents use are important ), may reduce longterm CV morbidity amd maybe mortality. In those patients with longstanding diabetes, with established end-organi damage, intensive glucose control may not reverse the end-organ damage, and intensive glucose control here may push you to the brink of hypoglycemia and its attendant risk.
However, I am only a cardiologist, and so probably will not have the final say in this matter. One thing that we can agree on is that the pendulum is still swinging and obviously more work needs to be done. We only hope that future diabetic work will focus not just on glycemic control but also on patient end-points.

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