Continuous subcutaneous glucose monitoring in diabetic patients: A multicenter analysis

Abstract

OBJECTIVE - To evaluate the accuracy of a new subcutaneous glucose sensor (Glucoday; A. Menarini Diagnostics) compared with venous blood glucose measurement in type 1 and type 2 diabetic patients. RESEARCH DESIGN - A multicenter study was performed in 70 diabetic patients. A microdialysis fiber was inserted subcutaneously into the periumbelical region and perfused with a buffer solution. Glucose concentrations in the dialysate were then measured every 3 min by the glucose sensor over a 24-h period, during which nine venous blood samples were also collected throughout the day. RESULTS - Both the insertion of the fiber and the wearing of the device were well tolerated by the patients. Subcutaneous glucose levels were well correlated with venous glucose measurements (r = 0.9, P < 0.001) over a wide range (40-400 mg/dl) for up to 24 h, with a single-point calibration. An analysis of 381 data pairs showed a linear relationship between the GlucoDay and serial venous blood glucose levels, and 97% of the data fell in the A and B regions of the error grid analysis. Percentage bias between the GlucoDay and the blood venous levels was -2.0% in the hypoglycemic range (<70 mg/dl), 6.9% in the euglycemic range (70-180 mg/dl), and 11.2% in the hyperglycemic range (> 180 mg/dl). CONCLUSIONS - The GlucoDay system demonstrated high reliability and reported values that closely agreed with venous blood glucose measurements. The system was well tolerated and thus constitutes a relatively easy method to monitor glucose excursions in diabetic patients.