Reference values of glycemic variability indicators based on data from professional continuous glucose monitoring
Authors:   Tyumen State Medical University, Tyumen, Sudnitsyna A. S. , Suplotova L. A. ,   Tyumen State Medical University, Tyumen, Romanova N. V. ,   Regional Clinical Hospital No. 2, Tyumen, Sidorenko K. A. ,   Regional Clinical Hospital No. 2, Tyumen
Published: February 2021

Glycemia variability (GV) is an important factor in assessing the quality of glycemic control, as it contributes to the development of micro- and macrovascular complications of diabetes. Currently, there are mathematical methods for assessing GV, obtained using data from professional continuous glucose monitoring (PCGM). PCGM is one of the most modern, innovative technologies that allow assessing the quality of glycemic control and GV in patients with diabetes. The widespread clinical use of PCGM and the interpretation of the data obtained are limited by the lack of generally accepted reference values, as well as by the cost of technology. Reference ranges are needed to interpret the PCGM data in order to improve the quality of glycemic control in patients with carbohydrate metabolic disorders. Aim. Determine the reference ranges for glycemic variability indicators based on the data of professional continuous glucose monitoring to assess the quality of glycemic control. Materials and methods. We studied a population of people without carbohydrate metabolism disorders. A portable Medtronic iPro2 system (USA) was used for PCGM. A sensor was introduced into the subcutaneous fat of the subject, with the help of which 288 glucose measurements were made per day. Calibration was carried out by the subject himself 4 times a day using an individual glucometer. GV parameters were calculated using the Care Link iPro2 Medtronic and EasyGV version 9.0 programs in order to work out the reference ranges. The duration of the study inclusion period was 2 months. The observation period of the participants was 6 days. Results. As a result of the study, the following reference ranges were obtained: the median sensor glucose was 5.0 [4.8; 5.4] mmol/l, TIR – 98.0% [95.0; 99.0], TAR – 0.0% [0.0; 0.0], TBR – 1.5% [1.0; 5.0], GMI – 5.4% [5.3; 5.6], CV – 13.6% [11.6; 15.1], SD – 0.7 mmol/l [0.6; 0.9], MAGE – 1.5 mmol/l [1.2; 1.7], MAG – 0.7 mmol/l/hour [0.6; 0.9], M-Value – 3.7 mmol/l [1.8; 4.4], J-index – 10.4 [9.4; 13.1], CONGA – 4.6 mmol/l [4.5; 5.0], HBGI – 0.7 [0.6; 0.9], LBGI – 2.9 [1.5; 3.2], ADRR – 1.1 [1.0; 2.3]. When conducting a comparative analysis of indicators of glycemic variability, it was found that there were no statistically significant differences depending on age, gender and BMI. Only TBR had statistically significant gender differences (p = 0.007). When carrying out the correlation analysis, only GMI, sensor glucose, M-value, J-index, CONGA, LBGI indicators were statistically significantly correlated with all indicators of the time spent in the ranges. Conclusion. In the course of the study, reference ranges for GV indicators were determined – TIR, TAR, TBR, GMI, CV, sensor glucose, SD, MAGE, MAG, M-Value, J-index, CONGA, HBGI, LBGI, ADRR in the russian population. The obtained values will help physicians in the interpretation of the PNMG data, the wider use of the method in clinical practice, and the expansion of diagnostic capabilities for disorders of carbohydrate metabolism.