Glycostator: a novel technology to summarize blood glucose control in patients with diabetes mellitus.
BACKGROUND
Glycostator is a diabetes management software package consisting of 3 indicators-"time-averaged glucose (TAG)," "virtual A1c (VA1c)," and "lability index"-all devised for statistical manipulation of capillary glucose data and assessment of overall glycemic control. The TAG approximates the average value of the function of blood glucose versus time, adding the element of time to the computation of the mean glucose value. It mitigates the major pitfall of the arithmetical averaging methods currently available in glucose-monitoring devices: bias toward glycemic extremes. With use of the TAG value and a linear function, Glycostator calculates VA1c, a statistical emulation of the laboratory hemoglobin A1c (HgbA1c).


METHODS
We examined the relationship between Glycostator-calculated VA1c and laboratory-determined HgbA1c in 57 patients.


RESULTS
Glycostator VA1c results were within 15% of concomitant laboratory HgbA1c values in 82% of the patients studied. Further analysis revealed that 60 to 90 days of testing and an average of 3 or more finger-stick glucose tests per day optimized the accuracy of the VA1c as a predictor of HgbA1c (91% of these patients' VA1c values were within 15% of the concomitant HgbA1c laboratory value).


CONCLUSIONS
In patients who test blood glucose frequently, VA1c complements HgbA1c as a measure of overall glucose control and has the advantage of being updated after each blood glucose test for patient and physician feedback. Glycostator parameters are calculated by using recurrence relation algorithms that can be easily implemented on currently available blood glucose monitors.
Harrell
R Mack
RM
North Broward Diabetes Center, Broward Health and Nova Southeastern University, Deerfield Beach, Florida 33064, USA.
Abensour
Daniel S
DS
D001786:Blood Glucose / Q000032:analysis*; D015190:Blood Glucose Self-Monitoring / Q000295:instrumentation / Q000379:methods; D003920:Diabetes Mellitus / Q000097:blood*; D001330:Electronic Data Processing / Q000295:instrumentation / Q000379:methods; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D018670:Monitoring, Ambulatory / Q000295:instrumentation* / Q000379:methods*; D012189:Retrospective Studies; D012984:Software; D013997:Time Factors
D001786:Blood Glucose; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human