Management of type 2 diabetes: long-awaited evidence of benefits after blood sugar control
Prescrire international 8(43): 147-152
1999
ISSN/ISBN: 1167-7422 PMID: 11503841 Document Number: 510618
(1) The UKPDS trial was a very large, complex, comparative study with methodological weaknesses such as the absence of blinding. It showed that lowering the blood glucose level in patients with type 2 diabetes reduces the risk of clinical complications, especially diabetic microangiopathy. (2) In contrast, glycaemic control had no statistically significant impact on mortality. (3) Contrary to findings in a previous trial, glucose-lowering sulphonylureas and insulin did not increase cardiovascular morbidity or mortality in the UKPDS study. (4) Glibenclamide was the only drug tested that yielded a statistically significant reduction in the risk of clinical complications linked to type 2 diabetes. (5) Strict glycaemic control with a glucose-lowering sulphonylurea or insulin was associated with hypoglycaemic episodes in approximately a quarter of patients each year. (6) Metformin gave conflicting results that are difficult to explain: metformin reduced mortality in overweight patients with type 2 diabetes; but in diabetic patients poorly controlled by glucose-lowering sulphonylureas, mortality was higher in the group treated with the sulphonylurea + metformin combination than in the group that continued treatment with a sulphonylurea alone. (7) Currently, the results of the UKPDS trial are the only available clinical data on which to base the choice of treatment for type 2 diabetic patients aged between 25 and 65 years. When a glucose-lowering drug is considered necessary and is not contraindicated, the first-line choice is glibenclamide for diabetics who are not overweight, and metformin for those who are.