Subcutaneous glucose monitoring with GlucoDay: comparison of the results to those obtained with the endocrine artificial pancreas.

Objective: This study was undertaken to assess the accuracy of GlucoDay- a portable detector of subcutaneous glucose--by comparing the results to those obtained by Biostator an established and reliable method for continuous glucose measurement in whole blood.

Design: Subjects with type 1 diabetes (n:6), subjects with type 2 diabetes (n:6), and six healthy controls were studied for 24 hours; they consumed three main meals. The GlucoDay was connected to the subjects by inserting a microfibre probe into the periumbilical subcutaneous area, whilst the Biostator was inserted by a double-lumen catheter into an antecubital vein. A third catheter was inserted into a separate vein for blood withdrawal to measure glucose by the hexokinase method.

Results: The three methods (GlucoDay-Biostator-hexokinase) were equally accurate in measuring glucose levels (p = 0.233, Kruskall-Wallis test). The glucose measurements performed with GlucoDay and Biostator were significantly correlated with those performed with hexokinase (p < 0.001, r2 = 66.65% and p < 0.001, r2 = 64.4%, respectively, using simple regression analysis).

Conclusions: Measurements of glucose fluctuations in the subcutaneous tissue with the GlucoDay were close to those in blood determined by the Biostator. GlucoDay is therefore a reliable method for continuous glucose monitoring and may prove useful for optimizating treatment in patients with type 1 or type 2 diabetes.