Abstract

*Gordana Bukara – Radujkovic

ABSTRACT

Introduction/aim. Through retroactive analysis and statistical processing of the data obtained in the original research conducted in 2016, we want to establish which of the modern parameters of good metabolic control (Time In Range -TIR, Coefficient of Variation – CV and Area Under the Curve below limit - AUC) had the greatest influence on glycated hemoglobin A1C - HbA1c, and whether it is in accordance with modern diagnostic recommendations for the treatment of type 1 diabetes mellitus in the pediatric population. The subjects in the original research were using a professional type of device for continuous monitoring, a blind type of device, and did not have immediate real-time insight into the glycemic values measured by the same, so they could not affect the results obtained. Methods. 24 children with type 1 diabetes mellitus (10 boys and 14 girls), aged 5 to 18 years old (average 12.0 ± 3.3), with an average duration of diabetes of 2.5 years, participated in the study. All subjects were treated with multiple daily insulin injections – MDI. According to the study protocol, the subjects were expected to perform control laboratory tests (HbA1c) and certain anthropometric measurements (height, weight, Body Mass Index - BMI) before the beginning of the examination. Each subject had to use a device for professional glucose monitoring once a month for seven days, three times over a three-month period. After each use of the device, the results were discussed with the subject, and if necessary, insulin doses were changed and advice was given on proper nutrition. After three months, HbA1c was again measured in the laboratory. Statistical analysis. Initial HbA1c was 7.78±1.17 (min.: 5.5%; max.: 10%). During the period of using the professional device for continuous glucose monitoring, there was a decrease in laboratory-measured HbA1c, and after three months the laboratory-measured average value was 7.34±0.84 (min.: 5.60%; max.: 8.90%). The highest correlation coefficient and the only one that shows statistical significance in connection with laboratory measured HbA1c after three months is the time spent in the target range or TIR, and this correlation is negative. A linear regression model of the dependence of HbA1c on variables (TIR, CV, AUC below) was set up. The obtained R value of 0.820 (R2=0.673) tells us that the regression of HbA1c 67.3% is influenced by these three variables, the statistically significant of which is TIR (t=-5.411, p?0.01). Conclusion. Subsequent statistical processing of the results showed that the decrease of HbA1c in the original research was most influenced by TIR, which coincides with modern methods and diagnostic recommendations. CV, as well as AUC did not show a direct impact on HbA1c, but did show an impact on TIR, which can be explained by the imperfections of the research itself. Through statistical analysis in this paper, we have shown that all parameters are related and that one depends on the other, so a TIR of 70% does not mean that there is no variability or hypoglycemic episodes, and therefore clinicians must observe all the data obtained using CGM devices in order to determine a good therapy.