Scientific Studies of Glucose Control

The debate concerning the role of chronically raised blood glucose in the genesis of diabetic complications has raged since the 1930’s. Observational and cross sectional studies suggested that patients with lower blood glucose had lower rates of diabetic complications, but it was argued that these patients had a “milder” form of diabetes. Two large, prospective groups of studies have now been completed and as one leading author now states: “The debate about blood sugar control in diabetes is now ended”. The diabetes control and complications trial (D.C.C.T) from North America was a 10-year prospective study in 1443 Type 1 patients, of the effect of near normoglycaemia. The results show that the onset and progression of clinically important diabetic complications is reduced by between 46 to 76% (depending upon which complication) when compared with conventionally treated patients. The larger and longer studies of the UK prospective diabetes group have recently been recently published (U.K.P.D.S.). These multicentre studies of the effect of intensive blood sugar and blood pressure control in over 5000 people with Type 2 diabetes conclusively demonstrate that the rate of both micro and macrovascular complications are reduced with improved blood glucose and blood pressure control.

Assessment of Control

Glycaemic control is assessed and achieved by people monitoring their own glucose using capillary blood obtained usually from a finger prick, measured with sensing strips and meters. An estimate of the success of glycaemic control can be made by the measurement of the proportion of haemoglobin A1 that is joined with glucose. This is the haemoglobin A1c. The D.C.C.T gives us the target of helping Type 1 diabetes patients achieve fasting blood glucose of less than 7mmol, and a Haemoglobin A1c of less than 7.2%. The U.K.P.D.S gives us the target of helping Type 2 diabetes patients achieve fasting blood glucose of less than 7mmol, and a Haemoglobin A1c of less than 7.0%. Unfortunately, both studies have shown that there is increased hypoglycaemia and greater weight gain in the well-controlled groups. These two groups of studies are milestones in diabetes research and we now have the challenge of how we are going to achieve these targets for blood pressure and glycaemic control in the clinical environme

Achieving tight control