The Clinical Use Of Continuous Glucose Monitoring System In Impaired Glucose Regulation Subjects

The impaired glucose regulation is not only a state between normal glucose tolerance (NGT) and diabetes mellitus(DM), but also risk factor to develop DM and cardiovascular diseases (CVD ) . In IGR stage, blood glucose is higher than nomal glucose and also combined with macroangiopathy. many trials have proven that blood fluctuation is associated with those complications, so to get more detail and integrate glucose information is very important, the continuous glucose monitoring system (CGMS) has offered valuable assistant for investigating the blood glucose profile. In this study, we evaluate the accuracy of CGMS in outpatient condition and in rapid changing situation, and analyze the characters of daily glucose profiles in various glucose regulation subjects.Objective1. To evaluate the accuracy of MiniMed CGMS in outpatient condition.2. To assess the accuracy of the MiniMed continuous glucose monitoring system(CGMS) during rapid blood glucose changing condition.3. To investigate the characteristics of daily glucose profiles in various glucose regulation subjects using CGMS.Methods1. To analyze the data of CGMS from 28 inpatients and 30 outpatients, using correlation coefficient and error -grid analysis (EGA) to assess the accuracy of CGMS in outpatient condition.2. Totally 48 non-diabetes were participated in the study. Each one wore CGMS for three days, oral glucose tolerance tests were carried out on the third day, testing Omin, 30min,1h and 2h blood glucose. using correlation coefficient,EGA to assess the accuracy of CGMS in rapid blood glucose changing situation.3. Totally 10 I-IFG,10 I-IGT and 10 IFG/IGT subjects diagnosed by twice 75g oral glucose tolerance test (OGTT) were enrolled,meatime,10 normal glucose subjects were chosen for comparison. CGMS were carried out for 3 days in these subjects with daily customs fixed.Results1. ①The CGMS examination was well accepted in all patients. ②Over 95% of the paired value were qualified well and were interpretable by the CGMS program, both in the inpatient and outpatient groups. ③The Correlation coefficient, between sensor glucose and Capillary glucose values as well as plasma glucose values, were 0.94,0.85 in the inpatient group and 0.83, 0.84 in the outpatient group(P<0.001). ④Comparing the two groups, the mean absolute difference and relative difference, between sensor and plasma glucose values, had no differences (P>0.05) ,however, between sensor and capillary glucose values, the difference were observed (P<0.05) , but they were still in the acceptable range(mean relative differences≤20%). ⑤ EGA showed that 100% of the data fell in the A and B zones, both in the inpatient and outpatient condition.2. ①CGMS values and blood glucose values were correlated well in stable,rapid rising and falling glucose situation. ②Comparing to stable situation, the mean absolute difference and relative difference between CGMS and blood glucose were increased during rapid glucose changing condition (P<0.01) ,but they were still in the acceptable range. ③)EAG showed that 100% of the data fell into the A and B zones in all situations, ④blood glucose values preceded the CGMS values, irrespective of whether glucose is rising or falling, with a range of 6.37±4.33min.3. ①Compared to NGT group, the mean blood glucose of 24h and after meals mean glucose were higher in I-IFG,I-IGT and IFG/IGT groups (P＜0.01), especially for IFG/IGT group.②Compared to NGT, I-IFG groups, the increasingof blood glucose after meals and standard deviation of blood glucose were significant in I-IGT and IFG/IGT groups (P<0.01);mean values of daily deviation was increasing gradually, NGT, I-IFG,I-IGT and IFG/IGT. ③The blood glucose increased more quickly after breakfast in all groups. Compared to NGT group, the peak glucose values after meals were higher in I-IFG,I-IGT and IFG/IGT groups, especially for IFG/IGT group; The moments of glucose reaching peak values after meals were delayed in I-IGT and IFG/IGT groups.④In the 4 groups, the percentage of average postprandial TpG≥7.8mmol/L were 2.3±1.2%,18.4±2.5% 26.7±3.7% and 36.9±3.0%.Conclusion1. CGMS has great accuracy in blood glucose monitoring in outpatient condition.2. CGMS can provide an accurate reflection of blood glucose during rapid glucose changing condition and a small time lag were observed between them.3. ①CGMS data could accurately reflect daily 24h blood glucose profiles in various impaired glucose regulation. In IGR stage, the mean blood glucose values, deviation of blood glucose values in daytime and between daytime, as well as the percentage of TpG≥7.8mmol/L were higher than NGT group, especially for IFG/IGT group. This indicates it's necessary to take action in the early stage for IGR stage.