The relationship between glycosylated hemoglobin, time-in-range and glycemic variability in type 1 diabetes patients under flash glucose monitoring

Abstract Aims Continuous glucose monitoring (CGM) overcomes the limitations of glycated hemoglobin (HbA1c). This study was to investigate the relationship between CGM metrics and laboratory HbA1c in pregnant women with type 1 diabetes. Methods An observational study enrolled pregnant women with type 1 diabetes who wore CGM devices during pregnancy and postpartum from 11 hospitals in China from January 2015 to June 2019. CGM data were collected to calculate time-in-range (TIR), time above range (TAR), time below range (TBR), and glycemic variability parameters. Relationships between the CGM metrics and HbA1c were explored. Linear and curvilinear regressions were conducted to investigate the best-fitting model to clarify the influence of HbA1c on the TIR-HbA1c relationship during pregnancy. Results A total of 272 CGM data and corresponding HbA1c from 98 pregnant women with type 1 diabetes and their clinical characteristics were analyzed in this study. Mean HbA1c and TIR were 6.49±1.29% and 76.16±17.97% during pregnancy, respectively. HbA1c was moderately correlated with TIR 3.5-7.8(R= -0.429, P=0.001), mean glucose (R= 0.405, P=0.001) and TAR 7.8 (R=0.435, P=0.001), but was weakly correlated with TBR 3.5 (R=0.034, P=0.001) during pregnancy. On average, a 1% (11 mmol/mol) decrease in HbA1c corresponded to an 8.5% increase in TIR 3.5-7.8. During pregnancy, HbA1c of 6.0%, 6.5% and 7.0% were equivalent to a TIR 3.5-7.8 of 78%, 74%, and 69%, respectively. Conclusions We found that there was a moderate correlation between HbA1c and TIR 3.5-7.8 during pregnancy. To achieve the HbA1c target <6.0%, pregnant women with type 1 diabetes should strive for TIR 3.5-7.8 >78% (18h 43min) during pregnancy.

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Hybrid Closed-Loop Insulin Delivery Systems for People With Type 1 Diabetes

Canadian Journal of Health Technologies ◽

10.51731/cjht.2021.89 ◽

2021 ◽

Vol 1 (6) ◽

Author(s):

Health Technology Assessment Team

Keyword(s):

Type 1 Diabetes ◽

Closed Loop ◽

Glucose Monitoring ◽

Glycemic Variability ◽

Insulin Delivery ◽

Monitoring Methods ◽

Expert Review ◽

Expert Review Panel ◽

Time In Range

The CADTH Health Technology Expert Review Panel (HTERP) suggests that hybrid closed-loop insulin delivery (HCL) systems hold promise for the care of people with type 1 diabetes. HTERP considers that, at present, there are insufficient long-term data on clinically relevant and patient-important outcomes to recommend how extensive the role of HCL systems should be in care. HTERP recommends the collection of robust and comparative data for consideration of future reassessments that compare HCL systems to existing insulin delivery and glucose monitoring methods in terms of glycated hemoglobin (hemoglobin A1C); time-in-range; time above and below range; glycemic variability; quality of life; patient, parent or caregiver, and health care provider satisfaction; diabetes-related complications; discontinuation rates; and health system impact. Robust data are collected in well-designed comparative studies that are, among other considerations, of sufficient duration to ensure a clinically meaningful outcome assessment.

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Impact of COVID-19 Lockdown on Glycemic Control in Adults with Type 1 Diabetes Mellitus

Journal of the Endocrine Society ◽

10.1210/jendso/bvaa149 ◽

2020 ◽

Vol 4 (12) ◽

Author(s):

Begoña Pla ◽

Alfonso Arranz ◽

Carolina Knott ◽

Miguel Sampedro ◽

Sara Jiménez ◽

...

Keyword(s):

Diabetes Mellitus ◽

Type 1 Diabetes ◽

Glycemic Control ◽

Type 1 Diabetes Mellitus ◽

Glycosylated Hemoglobin ◽

Glucose Monitoring ◽

Glycemic Variability ◽

Glucose Management ◽

The Impact

Abstract Aim To examine the impact of the lockdown caused by the COVID-19 pandemic on both the glycemic control and the daily habits of a group of patients with type 1 diabetes mellitus (T1DM) using flash continuous glucose monitoring devices (flash CGMs). Methods Retrospective analysis based on all the information gathered in virtual consultations from a cohort of 50 adult patients with T1DM with follow-up at our site. We compared their CGM metrics during lockdown with their own previous data before the pandemic occurred, as well as the potential psychological and therapeutic changes. Results We observed a reduction of average glucose values: 160.26 ± 22.55 mg/dL vs 150 ± 20.96 mg/dL, P = .0009; estimated glycosylated hemoglobin: 7.21 ± 0.78% vs 6.83 ± 0.71%, P = .0005; glucose management indicator 7.15 ± 0.57% vs 6.88 ± 0.49%; P = .0003, and glycemic variability: 40.74 ± 6.66 vs 36.43 ± 6.09 P < .0001. Time in range showed an improvement: 57.46 ± 11.85% vs a 65.76 ± 12.09%, P < .0001, without an increase in percentage of time in hypoglycemia. Conclusions COVID-19 lockdown was associated with an improvement in glycemic control in patients with T1DM using CGMs.

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Improved Time in Range and Glycemic Variability With Sotagliflozin in Combination With Insulin in Adults With Type 1 Diabetes: A Pooled Analysis of 24-Week Continuous Glucose Monitoring Data From the inTandem Program

Diabetes Care ◽

10.2337/dc18-2149 ◽

2019 ◽

Vol 42 (5) ◽

pp. 919-930 ◽

Cited By ~ 23

Author(s):

Thomas Danne ◽

Bertrand Cariou ◽

John B. Buse ◽

Satish K. Garg ◽

Julio Rosenstock ◽

...

Keyword(s):

Type 1 Diabetes ◽

Continuous Glucose Monitoring ◽

Glucose Monitoring ◽

Glycemic Variability ◽

Pooled Analysis ◽

Monitoring Data ◽

Time In Range

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Exploring the inter-subject variability in the relationship between glucose monitoring metrics and glycated hemoglobin for pediatric patients with type 1 diabetes

Journal of Pediatric Endocrinology and Metabolism ◽

10.1515/jpem-2020-0725 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Pietro Bosoni ◽

Valeria Calcaterra ◽

Valentina Tibollo ◽

Alberto Malovini ◽

Gianvincenzo Zuccotti ◽

...

Keyword(s):

Type 1 Diabetes ◽

Glycated Hemoglobin ◽

Glucose Monitoring ◽

Daily Injection ◽

Target Range ◽

Freestyle Libre ◽

Subject Variability ◽

Time In Range ◽

The Relationship

Abstract Objectives Despite the widespread diffusion of continuous glucose monitoring (CGM) systems, which includes both real-time CGM (rtCGM) and intermittently scanned CGM (isCGM), an effective application of CGM technology in clinical practice is still limited. The study aimed to investigate the relationship between isCGM-derived glycemic metrics and glycated hemoglobin (HbA1c), identifying overall CGM targets and exploring the inter-subject variability. Methods A group of 27 children and adolescents with type 1 diabetes under multiple daily injection insulin-therapy was enrolled. All participants used the isCGM Abbott’s FreeStyle Libre system on average for eight months, and clinical data were collected from the Advanced Intelligent Distant-Glucose Monitoring platform. Starting from each HbA1c exam date, windows of past 30, 60, and 90 days were considered to compute several CGM metrics. The relationships between HbA1c and each metric were explored through linear mixed models, adopting an HbA1c target of 7%. Results Time in Range and Time in Target Range show a negative relationship with HbA1c (R2>0.88) whereas Time Above Range and Time Severely Above Range show a positive relationship (R2>0.75). Focusing on Time in Range in 30-day windows, random effect represented by the patient’s specific intercept reveals a high variability compared to the overall population intercept. Conclusions This study confirms the relationship between several CGM metrics and HbA1c; it also highlights the importance of an individualized interpretation of the CGM data.

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