Letter to the Editor regarding "Accuracy and Reliability of the Sinocare iCan i3 Continuous Glucose Monitoring System".

In recent years, meters for continuous monitoring of interstitial fluid glucose have been introduced to help people with type 1 diabetes mellitus (T1DM) to achieve better control of their disease. The objective of this project was to summarise the evidence on the clinical effectiveness and cost-effectiveness of the MiniMed(®) Paradigm™ Veo system (Medtronic Inc., Northridge, CA, USA) and the Vibe™ (Animas(®) Corporation, West Chester, PA, USA) and G4(®) PLATINUM CGM (continuous glucose monitoring) system (Dexcom Inc., San Diego, CA, USA) in comparison with multiple daily insulin injections (MDIs) or continuous subcutaneous insulin infusion (CSII), both with either self-monitoring of blood glucose (SMBG) or CGM, for the management of T1DM in adults and children. A systematic review was conducted in accordance with the principles of the Centre for Reviews and Dissemination guidance and the National Institute for Health and Care Excellence Diagnostic Assessment Programme manual. We searched 14 databases, three trial registries and two conference proceedings from study inception up to September 2014. In addition, reference lists of relevant systematic reviews were checked. In the absence of randomised controlled trials directly comparing Veo or an integrated CSII + CGM system, such as Vibe, with comparator interventions, indirect treatment comparisons were performed if possible. A commercially available cost-effectiveness model, the IMS Centre for Outcomes Research and Effectiveness diabetes model version 8.5 (IMS Health, Danbury, CT, USA), was used for this assessment. This model is an internet-based, interactive simulation model that predicts the long-term health outcomes and costs associated with the management of T1DM and type 2 diabetes. The model consists of 15 submodels designed to simulate diabetes-related complications, non-specific mortality and costs over time. As the model simulates individual patients over time, it updates risk factors and complications to account for disease progression. Fifty-four publications resulting from 19 studies were included in the review. Overall, the evidence suggests that the Veo system reduces hypoglycaemic events more than other treatments, without any differences in other outcomes, including glycated haemoglobin (HbA1c) levels. We also found significant results in favour of the integrated CSII + CGM system over MDIs with SMBG with regard to HbA1c levels and quality of life. However, the evidence base was poor. The quality of the included studies was generally low, often with only one study comparing treatments in a specific population at a specific follow-up time. In particular, there was only one study comparing Veo with an integrated CSII + CGM system and only one study comparing Veo with a CSII + SMBG system in a mixed population. Cost-effectiveness analyses indicated that MDI + SMBG is the option most likely to be cost-effective, given the current threshold of £30,000 per quality-adjusted life-year gained, whereas integrated CSII + CGM systems and Veo are dominated and extendedly dominated, respectively, by stand-alone, non-integrated CSII with CGM. Scenario analyses did not alter these conclusions. No cost-effectiveness modelling was conducted for children or pregnant women. The Veo system does appear to be better than the other systems considered at reducing hypoglycaemic events. However, in adults, it is unlikely to be cost-effective. Integrated systems are also generally unlikely to be cost-effective given that stand-alone systems are cheaper and, possibly, no less effective. However, evidence in this regard is generally lacking, in particular for children. Future trials in specific child, adolescent and adult populations should include longer term follow-up and ratings on the European Quality of Life-5 Dimensions scale at various time points with a view to informing improved cost-effectiveness modelling. PROSPERO Registration Number CRD42014013764. The National Institute for Health Research Health Technology Assessment programme.

The accuracy of the GlucoWatch G2 Biographer (GW2B; Cygnus, Inc., Redwood City, CA) was assessed in children and adolescents with type 1 diabetes mellitus (T1DM). During a 24-h clinical research center stay, 89 children and adolescents with T1DM (3.5-17.7 years old) wore 174 GW2Bs and had frequent serum glucose determinations during the day and night and during insulin-induced hypoglycemia and meal-induced hyperglycemia, resulting in 3672 GW2B-reference glucose pairs. The median relative absolute difference between the GW2B and reference glucose values was 16% (25th, 75th percentiles = 7%, 29%). The proposed International Organisation for Standardisation criteria were met for 60% of sensor values. Accuracy was better at higher serum glucose levels than low glucose levels. Accuracy degraded slightly as the sensor aged. Time of day, subject age, gender, or body mass index did not impact GW2B accuracy. There were no cases of serious skin reactions. Although the accuracy of this generation of sensor does not approach that of current home glucose meters, the majority of sensor glucose values are within 20% of the serum glucose. This level of accuracy may be sufficient for detecting trends and modifying diabetes management. Further longitudinal outpatient studies are needed to assess the utility of the GW2B as a management tool to improve glycemic control and decrease the incidence of severe hypoglycemia in children with diabetes.

This study aimed at evaluating and comparing the performance of a new generation of continuous glucose monitoring (CGM) system versus other CGM systems, under daily lifelike conditions. A total of 10 subjects (7 female) were enrolled in this study. Each subject wore two Dexcom G4™ CGM systems in parallel for the sensor lifetime specified by the manufacturer (7 days) to allow assessment of sensor-to-sensor precision. Capillary blood glucose (BG) measurements were performed at least once per hour during daytime and once at night. Glucose excursions were induced on two occasions. Performance was assessed by calculating the mean absolute relative difference (MARD) between CGM readings and paired capillary BG readings and precision absolute relative difference (PARD), i.e., differences between paired CGM readings. Overall aggregate MARD was 11.0% (n = 2392). Aggregate MARD for BG <70 mg/dl was 13.7%; for BG between 70 and 180 mg/dl, MARD was 11.4%; and for BG >180 mg/dl, MARD was 8.5%. Aggregate PARD was 7.3%, improving from 11.6% on day 1 to 5.2% on day 7. The Dexcom G4 CGM system showed good overall MARD compared with results reported for other commercially available CGM systems. In the hypoglycemic range, where CGM performance is often reported to be low, the Dexcom G4 CGM system achieved better MARD than that reported for other CGM systems in the hypoglycemic range. In the hyperglycemic range, the MARD was comparable to that reported for other CGM systems, whereas during induced glucose excursions, the MARD was similar or slightly worse than that reported for other CGM systems. Overall PARD was 7.3%, improving markedly with sensor life time.

The continuous glucose monitoring system showed to be a very safe, well-tolerated and highly accurate method, with a low complication rate. It is a good method to identify glucose excursion and postprandial hyperglycemia, and to improve metabolic changes in therapeutic strategies, with a significant impact on the A1c levels of pediatric diabetic patients. The efficacy of the continuous glucose monitoring system in detecting hypoglycemia is still unclear in the medical literature.

Currently, patients with diabetes may choose between two major types of system for glucose measurement: blood glucose monitoring (BGM) systems measuring glucose within capillary blood and continuous glucose monitoring (CGM) systems measuring glucose within interstitial fluid. Although BGM and CGM systems offer different functionality, both types of system are intended to help users achieve improved glucose control. Another area in which BGM and CGM systems differ is measurement accuracy. In the literature, BGM system accuracy is assessed mainly according to ISO 15197:2013 accuracy requirements, whereas CGM accuracy has hitherto mainly been assessed by MARD, although often results from additional analyses such as bias analysis or error grid analysis are provided. The intention of this review is to provide a comparison of different approaches used to determine the accuracy of BGM and CGM systems and factors that should be considered when using these different measures of accuracy to make comparisons between the analytical performance (ie, accuracy) of BGM and CGM systems. In addition, real-world implications of accuracy and its relevance are discussed.

Glycemic control in critically ill patients has been the topic of an interesting debate during the last decade. An accurate continuous glucose monitoring system is essential to better understand this field. This prospective study thus evaluates the accuracy and technical feasibility of a continuous glucose monitoring system using intravascular microdialysis. Thirty patients undergoing cardiac surgery were monitored using a triple-lumen central venous catheter (Eirus TLC; Eirus Medical AB, Solna, Sweden) with an integrated microdialysis function. The catheter functions as a central venous catheter, enabling blood sampling and administration of infusions and medication while simultaneously providing continuous glucose monitoring. The patients were monitored for up to 48 h postoperatively. As reference, arterial blood gas samples were taken every hour and analyzed in a blood gas analyzer. Six hundred seven paired samples were obtained for analysis. Using Clarke Error Grid analysis, 100% of the paired samples were in Zones A+B, and 97% were in Zone A. Mean difference (bias) was -0.12 mmol/L, and mean absolute relative difference was 5.6%. Of the paired samples, 97.5% were correct according to International Organization for Standardization criteria. Bland-Altman analysis showed bias ± limits of agreement were -0.12 ± 0.7 mmol/L. No hypoglycemic episodes were observed. Central venous microdialysis is an accurate and reliable method for continuous blood glucose monitoring up to 48 h in patients undergoing cardiac surgery. With the microdialysis function integrated in a central venous catheter, no extra device for the continuous glucose monitoring is required. The system may be useful in critically ill patients.

To evaluate the accuracy, utility and complications of continuous glucose monitoring system in children and adolescents with type 1 diabetes. This retrospective study assessed 16 type 1 diabetic patients (16.12+/-4.41 years) submitted to continuous glucose monitoring system (Medtronic; Northridge, CA) for 72 hours. The following parameters were analyzed: mean capillary glucose level and mean glucose value measured by the continuous glucose monitoring system; glucose excursions (continuous glucose monitoring system vs. capillary glucose measurement), postprandial hyperglycemia (NR < 140 mg/dl), nocturnal hypoglycemia, complications (trauma, local infection, disconnection) and therapeutic management after continuous glucose monitoring. A1c levels were measured at the beginning and after 3 months of the study. The mean capillary glucose values were 214.3+/-66.5 mg/dl vs. 207.6+/-54.6 mg/dl by continuous glucose monitoring system, with a significant correlation (p = 0.001). The correlation coefficient and mean absolute error were 0.86+/-0.21 and 12.6% of the median, respectively. The continuous glucose monitoring system was significantly more efficient in detecting glucose excursion than fingerstick capillary blood sampling (p = 0.04; W = 74), and postprandial hyperglycemia was identified in 60% of type 1 diabetic patients with a median value of 157 mg/dl (< 140 mg/dl). Nocturnal hypoglycemia was detected in 46.7% of these patients. The evaluation of A1c levels in eight (50%) patients before continuous glucose monitoring and after 3 months showed a significantly lower level of A1c in this population (8.18+/-1.5 vs. 7.28+/-1.3; p = 0.034). The therapeutic management of type 1 diabetes was changed in 100% of patients. No complications were detected in 93.7% of patients. The continuous glucose monitoring system showed to be a very safe, well-tolerated and highly accurate method, with a low complication rate. It is a good method to identify glucose excursion and postprandial hyperglycemia, and to improve metabolic changes in therapeutic strategies, with a significant impact on the A1c levels of pediatric diabetic patients. The efficacy of the continuous glucose monitoring system in detecting hypoglycemia is still unclear in the medical literature.

Continuous glucose monitoring has been proposed to optimize glucose control in critically ill patients. To achieve strict glucose regulation, accurate and reliable continuous glucose-monitoring systems are essential. Evaluation of a subcutaneous continuous glucose-monitoring system for use in critically ill patients. Pooled-data analysis of two prospective, randomized, controlled trials. An eight-bed medical intensive care unit of a university hospital. A total of 174 critically ill patients on intensive insulin therapy. Subcutaneous continuous glucose monitoring. Two thousand forty-five continuous glucose-monitoring system sensor glucose values were compared with arterial reference blood glucose levels, determined by a blood gas analyzer. Continuous glucose monitoring data were recorded continuously for up to 72 hrs by using a subcutaneous continuous glucose-monitoring sensor. The correlation of both methods and differences between continuous glucose-monitoring systems and reference values were calculated, as well as the conformity of continuous glucose-monitoring values with the International Organization for Standardization criteria (<0.83 mmol/L [15 mg/dL] difference for glucose values ≤ 4.12 mmol/L [≤ 75 mg/dL] and <20% difference for glucose values >4.12 mmol/L [>75 mg/dL]). The Pearson correlation coefficient was 0.92, showing strong correlation between the two methods. The intraclass correlation coefficient was 0.92, indicating that 92% of the variability is due to subjects and measurement occasions. Mean difference between continuous glucose-monitoring system and reference values was -0.10 mmol/L (confidence interval: -0.13 to -0.07) (-2 mg/dL [confidence interval: -2 to -1]) (continuous glucose-monitoring system minus reference) and absolute difference 0.44 mmol/L (confidence interval: 0.41-0.47) (8 mg/dL [confidence interval: 7-8]). According to the insulin titration error grid analysis, 99.1% of continuous glucose-monitoring system values were in the acceptable treatment zone. No continuous glucose-monitoring system measurements were found in the life-threatening zone, and 92.9% of the continuous glucose-monitoring system glucose values met the International Organization for Standardization criteria. The subcutaneous continuous glucose-monitoring system is reliable for use in critically ill patients and showed glucose values with a strong correlation to arterial reference blood glucose levels, determined by a blood gas analyzer.

Introduction: Continuous Glucose Monitoring (CGM) systems have evolved significantly, transforming the management of diabetes and expanding into various other fields. Originally developed to aid in diabetes management, CGM systems now offer real-time glucose tracking, providing insights into glycemic control, preventing hypoglycemia, and optimizing therapeutic decisions. These systems are used in type 1 and type 2 diabetes management, pregnancy, sports, and critical care. Despite their benefits, challenges such as cost and integration into routine care remain. Future research will be crucial to fully understand the long-term impact and cost-effectiveness of CGM systems. Aim of the study: This study aims to present the diverse applications and integrated benefits of Continuous Glucose Monitoring (CGM) systems. It focuses on their role in improving diabetes management, enhancing pregnancy outcomes, supporting athletic performance, and optimizing care in critical conditions. Materials and methods: A literature review was conducted using PubMed as the primary database. The search terms included: "continuous glucose monitoring", “CGM”, “diabetes mellitus", “diabetes mellitus type 1”, “diabetes mellitus type 2”. Conclusion: Continuous glucose monitoring (CGM) systems have significantly advanced diabetes care, offering precise, real-time glycemic data that support individualized treatment. This review highlights CGM’s broadening applications across diverse populations, including non-diabetic individuals, pregnant women, athletes, and critically ill patients. While strong evidence supports CGM’s clinical and behavioral benefits, further research is required to optimize cost-effectiveness, long-term outcomes, and broader implementation strategies. CGM represents a transformative tool in both chronic disease management and personalized health monitoring.

Continuous glucose monitoring systems - Current status and future perspectives of the flagship technologies in biosensor research -

This study is aimed at comparing the performance of three continuous glucose monitoring (CGM) systems following the Clinical and Laboratory Standards Institute's POCT05-A guideline, which provides recommendations for performance evaluation of CGM systems. A total of 12 subjects with type 1 diabetes were enrolled in this study. Each subject wore six CGM systems in parallel, two sensors of each CGM system [FreeStyle Navigator™ (Navigator), MiniMed Guardian® REAL-Time with Enlite sensor (Guardian), DexCom™ Seven® Plus 3rd generation (Seven Plus)]. Each sensor was used for the lifetime specified by the manufacturer. To follow POCT05-A recommendations, glucose excursions were induced on two separate occasions, and venous and capillary blood glucose (BG) concentrations were obtained every 15 min for five consecutive hours. Capillary BG concentrations were measured at least once per hour during the day and once at night. Parameters investigated were CGM-to-BG differences [mean absolute relative difference (MARD)] and sensor-to-sensor differences [precision absolute relative difference (PARD)]. Compared with capillary BG reference readings, the Navigator showed the lowest MARD, with 12.1% overall and 24.6% in the hypoglycemic range; for the Guardian and the Seven Plus, MARD was 16.2%/34.9% and 16.3%/32.7%, respectively. PARD also was lowest for the Navigator (9.6%/9.8%), followed by the Seven Plus (16.7%/25.5%) and the Guardian (18.1%/20.2%). During induced glucose excursions, MARD between CGM and BG was, again, lowest for the Navigator (14.3%), followed by the Seven Plus (15.8%) and the Guardian (19.2%). In this study, two sensors of each of the three CGM systems were compared in a setting following POCT05-A recommendations. The Navigator CGM system achieved more accurate results than the Guardian or the Seven Plus with respect to MARD and PARD. Performance in the hypoglycemic range was markedly worse for all CGM systems when compared with BG results.

IntroductionThe present study was aimed to evaluate the performance and safety of the Glunovo® real-time continuous glucose monitoring system (CGMS) in monitoring interstitial fluid glucose in adult participants with diabetes (at least 18 years old) using venous blood glucose as control.MethodsThis was a multicenter, self-controlled clinical trial, conducted in participants with diabetes from China, between March 2019 to October 2019. The CGMS was used by all the participants for a 14-day wear-in period. The real-time glucose values measured by Glunovo® CGMS were compared with venous blood glucose values measured by the Entwicklung, Konstruktion und Fertigung (EKF) blood glucose detector. The primary outcomes were the consistency rate of CGMS readings and venous blood glucose values (20/20% standard).ResultsA total of 78 participants (41 men, 37 women) and 156 CGMS sensors were included in the study. Among the included participants, 25 and 53 participants had type 1 and type 2 diabetes, respectively, with median age of 52.50 years (range 32–62 years). The overall agreement rate (20/20%) was 89.71% (95% CI 89.18–90.24%). It was observed that 99.08% (95% CI 98.91–99.24%) and 99.82% (95% CI 99.74–99.89%) of the measuring points fell within the A + B zones of the Clarke error grid analysis and Parkes/consensus error grid analysis, respectively. The mean absolute relative difference was 10.30% ± 4.86%. The probability of a glucose measurement falling within a range, when stratified by venous glucose measurements, ranged from 7.14% for 19.44–22.22 mmol/L to 79.21% for 4.44–6.67 mmol/L. There were 73 (41.24%) and 27 (57.45%) successful CGMS alarms for hypoglycemic and hyperglycemic events, respectively.ConclusionFrom the results, Glunovo® CGMS had excellent accuracy and limited clinical risk compared with venous blood glucose in the range of 2.2–22.2 mmol/L over 14 days.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13300-021-01171-2.

Evaluation of Metabolic Control Using a Continuous Subcutaneous Glucose Monitoring System in Patients with Type 1 Diabetes Mellitus who Achieved Insulin Independence after Islet Cell Transplantation

Diabetes Technology & TherapeuticsVol. 2, No. supplement 1 Orginal ArticlesContinuous Glucose Monitoring in Previously Unstudied Population SubgroupsTodd M. Gross and Anna ter VeerTodd M. GrossSearch for more papers by this author and Anna ter VeerSearch for more papers by this authorPublished Online:5 Jul 2004https://doi.org/10.1089/15209150050214096AboutSectionsPDF/EPUB Permissions & CitationsPermissionsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookTwitterLinked InRedditEmail FiguresReferencesRelatedDetailsCited byA Standard Approach to Continuous Glucose Monitor Data in Pregnancy for the Study of Fetal Growth and Infant Outcomes Teri L. Hernandez and Linda A. Barbour29 January 2013 | Diabetes Technology & Therapeutics, Vol. 15, No. 2Continuous Glucose Monitoring in Pregnancy: New Frontiers in Clinical Applications and Research1 November 2012 | Journal of Diabetes Science and Technology, Vol. 6, No. 6The Correlation and Accuracy of Glucose Levels between Interstitial Fluid and Venous Plasma by Continuous Glucose Monitoring SystemKorean Diabetes Journal, Vol. 34, No. 6Continuous Glucose Monitoring System in Free-Living Healthy Subjects: Results from a Pilot Study Giuseppe Derosa, Sibilla A.T. Salvadeo, Roberto Mereu, Angela D'Angelo, Leonardina Ciccarelli, Mario N. Piccinni, Ilaria Ferrari, Alessia Gravina, Pamela Maffioli, and Carmine Tinelli6 March 2009 | Diabetes Technology & Therapeutics, Vol. 11, No. 3Preclinical In Vivo Study of a Fluorescence Affinity Sensor for Short-Term Continuous Glucose Monitoring in a Small and Large Animal Model Ralph Dutt-Ballerstadt, Colton Evans, Ashok Gowda, and Roger McNichols13 September 2010 | Diabetes Technology & Therapeutics, Vol. 10, No. 6How to Assess and Compare the Accuracy of Continuous Glucose Monitors? I.M.E. Wentholt, A.A.M. Hart, J.B.L. Hoekstra, and J.H. DeVries8 February 2008 | Diabetes Technology & Therapeutics, Vol. 10, No. 2Future Management Approaches12 July 2013Accuracy of continuous nocturnal glucose monitoring after 48 and 72 hours in type 2 diabetes patients on combined oral and insulin therapyDiabetes & Metabolism, Vol. 30, No. 6Nocturnal hypoglycaemia in type 1 diabetes?consequences and assessment1 January 2004 | Diabetes/Metabolism Research and Reviews, Vol. 20, No. S2The Continuous Glucose Monitoring System During Pregnancy of Women with Type 1 Diabetes Mellitus: Accuracy Assessment Anneloes Kerssen, Harold W. De Valk, and Gerard H.A. Visser12 October 2004 | Diabetes Technology & Therapeutics, Vol. 6, No. 5The Public Health Impact of the MiniMed Continuous Glucose Monitoring System (CGMS®)—An Assessment of the Literature Dale R. Tavris and Azadeh Shoaibi25 August 2004 | Diabetes Technology & Therapeutics, Vol. 6, No. 4Experience with the Continuous Glucose Monitoring System® in a Medical Intensive Care Unit Philip A. Goldberg, Mark D. Siegel, Raymond R. Russell, Robert S. Sherwin, Joshua I. Halickman, Dawn A. Cooper, James D. Dziura, and Silvio E. Inzucchi5 July 2004 | Diabetes Technology & Therapeutics, Vol. 6, No. 3Glucose sensors: toward closed loop insulin deliveryEndocrinology and Metabolism Clinics of North America, Vol. 33, No. 1Enregistrement de la glycémie en continu : quelles retombées ?Annales d'Endocrinologie, Vol. 65Performance assessment of the Medtronic-MiniMed Continuous Glucose Monitoring System and its use for measurement of glycaemic control in Type 1 diabetic subjectsDiabetic Medicine, Vol. 20, No. 12The Accuracy of the CGMS™ in Children with Type 1 Diabetes: Results of the Diabetes Research in Children Network (DirecNet) Accuracy Study5 July 2004 | Diabetes Technology & Therapeutics, Vol. 5, No. 5Accuracy of the continuous glucose monitoring system in inpatient and outpatient conditionsDiabetes & Metabolism, Vol. 29, No. 2Clinical Performance of CGMS in Type 1 Diabetic Patients Treated by Continuous Subcutaneous Insulin Infusion Using Insulin AnalogsDiabetes Care, Vol. 26, No. 3Biosensors for in vivo glucose measurement: can we cross the experimental stageBiosensors and Bioelectronics, Vol. 17, No. 11-12Reproducibility of Glucose Measurements Using the Glucose SensorDiabetes Care, Vol. 25, No. 7Continuous Monitoring of the Subcutaneous Glucose Level in Freely Moving Normal and Diabetic Rats and in Humans with Type 1 Diabetes Reza Jamali, Johnny Ludvigsson, and Simin Mohseni5 July 2004 | Diabetes Technology & Therapeutics, Vol. 4, No. 3What's ahead in glucose monitoring?30 June 2015 | Postgraduate Medicine, Vol. 109, No. 4New technologies and therapeutic approaches for the management of pediatric diabetesCurrent Diabetes Reports, Vol. 1, No. 1 Volume 2Issue supplement 1Dec 2000 To cite this article:Todd M. Gross and Anna ter Veer.Continuous Glucose Monitoring in Previously Unstudied Population Subgroups.Diabetes Technology & Therapeutics.Dec 2000.27-34.http://doi.org/10.1089/15209150050214096Published in Volume: 2 Issue supplement 1: July 5, 2004PDF download

Continuous glucose monitoring (CGM) systems are more informative than the traditional self-monitoring of capillary blood glucose (BG). Although advances in CGM technology have significantly improved the clinical utility of CGM devices compared with earlier versions, it is often difficult to assess the accuracy and precision of current devices due to differences in assessment protocols and reporting of results. Because CGM sensor accuracy can impact both the clinical utility and patient acceptance of CGM use, it is important to consider the performance characteristics seen in the current systems when assessing the clinical value of this technology. Moreover, standardization of the metrics used to assess CGM accuracy and precision are needed to help developers, clinicians, and patients make informed decisions regarding the CGM systems they are considering. In this chapter, we discuss the most commonly used methods for the assessment of CGM system performance, the accuracy and reliability of current CGM systems, and the remaining unsolved technological and physiological hurdles.