Glycaemic instability is an underestimated problem in Type II diabetes

To assess the level of glycemic control by the measurement of 24 h blood glucose profiles and standard blood analyses under identical nutritional and physical activity conditions in type 2 diabetes patients and healthy, normoglycemic controls. RESEARCH DESIGN AND METHODS: A total of 11 male, type 2 diabetes patients and 11 healthy, matched controls participated in a 24 h continuous subcutaneous glucose monitoring (CGMS) assessment trial under strictly standardized dietary and physical activity conditions. In addition, fasting plasma glucose, insulin and HbA1c concentrations were measured, and an oral glucose tolerance test was performed to calculate indices of whole-body insulin sensitivity, oral glucose tolerance and/or glycemic control. RESULTS: In the healthy control group, hyperglycemia (blood glucose concentration =10 mmol/l) was hardly present (2+/-1 % or 0.4+/-0.2 / 24 h). However, in the type 2 diabetes patients hyperglycemia was experienced for as much as 55+/-7% of the time (13+/-2 h / 24 h) while using the same standardized diet. Breakfast-related hyperglycemia contributed most (46+/-7%, ANOVA, P<0.01) to the total amount of hyperglycemia and postprandial glycemic instability. In the diabetes patients, blood HbA1c contents correlated well with the duration of hyperglycemia and the postprandial glucose responses (P<0.05). CONCLUSIONS: CGMS measurements show that standard measures for glycemic control underestimate the amount of hyperglycemia prevalent during real-life conditions in type 2 diabetes. Given the macro- and microvascular damage caused by postprandial hyperglycemia, CGMS provides an excellent tool to evaluate alternative therapeutic strategies to reduce hyperglycemic blood glucose excursions