Time in Range Analysis and Glucose Variability in Type 1 Diabetic Patients with Different Stages of Chronic Kidney Disease

The aim: to assess the relationships between glucose variability (GV) parameters and renal function in patients with type 1 diabetes (T1D) at different stages of chronic kidney disease (CKD). Materials and Methods: We observed 127 patients with T1D, 48 M/79 F, from 18 to 72 years of age. Patients were divided into 5 groups: 1) no signs of CKD (CKD0), n=27; 2) CKD С1-C2, n=67; 3) CKD С3-C4, n=26; 5) CKD С5 (hemodialysis, n=7). Time in ranges and GV parameters: Mean Amplitude of Glucose Excursions (MAGE), Lability Index (LI), Low Blood Glucose Index (LBGI), High Blood Glucose Index (HBGI), 2-hour Continuous Overlapping Net Glycemic Action (CONGA), and Mean Absolute Glucose (MAG) were derived from 72-hour continuous glucose monitoring. Results: As compared to patients without CKD, the values of MAGE, LI, HBGI were increased significantly in patients with CKD C1-C2 (all p<0.05). No differences were found in all GV parameters between CKD C3-C4 and CKD0 groups. In patients on hemodialysis time in hyperglycemic range, MAGE, LI, CONGA and HBGI were significantly higher as compared to other groups (all p<0.05). In patients with CKD C3-C5 there were negative correlations between HBGI, CONGA and estimated glomerular filtration rate (eGFR). In patients with eGFR >60 ml/min/1.73m2 HbA1c levels correlated positively with mean monitored glucose, time in hyperglycemic range, HBGI, CONGA, MAGE, LI, and MAG. On the contrary, in patients with lower eGFR none of GV parameters correlated with HbA1c. Conclusions: The results demonstrate non-linear relationships between eGFR and GV parameters in patients with T1D.