Use of Continuous Glucose Monitoring in the Assessment and Management of Patients With Diabetes and Chronic Kidney Disease

Abstract

In developed countries, diabetes is the leading cause of chronic kidney disease (CKD) and accounts for 50% of incidence of end stage kidney disease. Despite declining prevalence of micro- and macrovascular complications, there are rising trends in renal replacement therapy in diabetes. Optimal glycemic control may reduce risk of progression of CKD and related death. However, assessing glycemic control in patients with advanced CKD and on dialysis (G4-5) can be challenging. Laboratory biomarkers, such as glycated haemoglobin (HbA1c), may be biased by abnormalities in blood haemoglobin, use of iron therapy and erythropoiesis-stimulating agents and chronic inflammation due to uraemia. Similarly, glycated albumin and fructosamine may be biased by abnormal protein turnover. Patients with advanced CKD exhibited heterogeneity in glycemic control ranging from severe insulin resistance to ‘burnt-out’ beta-cell function. They also had high risk of hypoglycaemia due to reduced renal gluconeogenesis, frequent use of insulin and dysregulation of counterregulatory hormones. Continuous glucose monitoring (CGM) systems measure glucose in interstitial fluid every few minutes and provide an alternative and more reliable method of glycemic assessment, including asymptomatic hypoglycaemia and hyperglycaemic excursions. Recent international guidelines recommended use of CGM-derived Glucose Management Index (GMI) in patients with advanced CKD although data are scarce in this population. Using CGM, patients with CKD were found to experience marked glycemic fluctuations with hypoglycemia due to loss of glucose and insulin during haemodialysis (HD) followed by hyperglycemia in the post-HD period. On the other hand, during peritoneal dialysis, patients may experience glycemic excursions with influx of glucose from dialysate solutions. These undesirable glucose exposure and variability may accelerate decline of residual renal function. Although CGM may improve the quality of glycemic monitoring and control in populations with CKD, further studies are needed to confirm the accuracy, optimal mode and frequency of CGM as well as their cost-effectiveness and user-acceptability in patients with advanced CKD and dialysis.

Continuous Glucose Monitoring and Reduced Diabetes-Related Hospitalizations in Patients with Type 2 Diabetes and CKD

“…24 Other publications support the important role that CGM can play in helping people with T2D and CKD stage 3-5 maintain glycemic control. 7,8,25 It is notable that while hospitalizations decreased a clinically meaningful and statistically significant amount, rates of hospitalization for acute dysglycemic events in this cohort of patients with CKD and T2D are still far higher than for patients with T2D, 2 underscoring the complexity of this population.…”

Applications of continuous glucose monitoring across settings and populations: Report from the 23rd Hong Kong diabetes and cardiovascular risk factors—East meets west symposium

“…Certain substances frequently encountered in advanced CKD could result in sensor interference. 33 Hypoxia or hyperoxia will falsely alter the reading of the glucoseoxidase-based glucose sensors by changing the concentration of oxygen at the initiation of the step-wise reaction chain. 34 Metabolites from icodextrin can result in falsely elevated glucose readings with glucose dehydrogenasepyrroloquinolinequinone glucometers in PD, 35 but mostly do not affect glucose-oxidase-based systems.…”

“…Minute‐to‐minute interstitial glucose is detected minute‐by‐minute by mostly glucose‐oxidase enzyme‐based sensors in the subcutaneous tissue. Certain substances frequently encountered in advanced CKD could result in sensor interference 33 . Hypoxia or hyperoxia will falsely alter the reading of the glucose‐oxidase‐based glucose sensors by changing the concentration of oxygen at the initiation of the step‐wise reaction chain 34 .…”

Evaluation of a Fourth-Generation Subcutaneous Real-Time Continuous Glucose Monitor (CGM) in Individuals With Diabetes on Peritoneal Dialysis

“…Peritoneal glucose exposure, especially hypertonic glucose solutions, induce greater interstitial glucose surge and glycemic variability ( 3 ). The accuracy of traditional glycemic markers (e.g., glycated hemoglobin [HbA 1c ]) is affected by use of iron and erythropoietin-stimulating agents ( 4 ). The latest Kidney Disease Improving Global Outcomes (KDIGO) guideline advocates the use of periodic continuous glucose monitoring (CGM) alongside HbA 1c in stage 4 to 5 chronic kidney disease ( 5 ).…”