Assessing non-adjunctive CGM safety at home and in new markets (ANSHIN).

INTRODUCTION: Continuous glucose monitoring (CGM) can guide treatment for people with type 1 (T1D) and type 2 diabetes (T2D). The ANSHIN study assessed the impact of non-adjunctive CGM use in adults with diabetes using intensive insulin therapy (IIT). MATERIALS AND METHODS: This single-arm, prospective, interventional study enrolled adults with T1D or T2D who had not used CGM in the prior 6 months. Participants wore blinded CGMs (Dexcom G6) during a 20-day run-in phase, with treatment based on fingerstick glucose values, followed by a 16-week intervention phase and then a randomized 12-week extension phase with treatment based on CGM values. The primary outcome was change in HbA1c. Secondary outcomes were CGM metrics. Safety endpoints were the number of severe hypoglycaemic (SH) and diabetic ketoacidosis (DKA) events. RESULTS: Of the 77 adults enrolled, 63 completed the study. Those enrolled had mean (SD) baseline HbA1c of 9.8% (1.9%), 36% had T1D, and 44% were ≥65 years old. Mean HbA1c decreased by 1.3, 1.0 and 1.0 percentage points for participants with T1D, T2D or age ≥65, respectively (p < .001 for each). CGM-based metrics including time in range also improved significantly. SH events decreased from the run-in period (67.3 per 100 person-years) to the intervention period (17.0 per 100 person-years). Three DKA events unrelated to CGM use occurred during the total intervention period. CONCLUSIONS: Non-adjunctive use of the Dexcom G6 CGM system improved glycaemic control and was safe for adults using IIT.

Longitudinal analysis of users transitioning from the Dexcom G5 to the G6 RT-CGM system in Germany, Sweden and the United Kingdom (2018-2020).

AIMS: Regional variations in the adoption of diabetes technology may be reflected in population-level metrics of glycaemic control. In this observational study, we aimed to assess the glycaemic impacts of transitioning from the Dexcom G5 Real-Time Continuous Glucose Monitoring (RT-CGM) System to the Dexcom G6 in three European countries. METHODS: Anonymised RT-CGM data (uploaded to the Dexcom Clarity app) were from users in Germany, Sweden, and the United Kingdom (UK) who transitioned from G5 to G6 between 9-12 months after G6 launched in 2018. Primary endpoints were percent time in hypoglycaemia, percent time in range (TIR), user retention rates, device utilisation, and urgent low soon (ULS) alert utilisation. Metrics were computed for 3-month intervals in the 2-year study window. RESULTS: In all three countries, the transition from G5 to G6 was associated with a clear decrease in hypoglycaemia. In months 0-3 after transitioning, the median percent time 〈3 mmol/L (54 mg/dL) and 〈3.9 mmol/L (70 mg/dL) decreased by [0.12-0.28] and [0.40-0.43] percentage points, respectively, with another [0.11-0.21] and [0.34-0.65] percentage point decrease in months 3-6 in the three countries analysed. TIR and CGM utilisation were sustained or improved slightly across all countries. At the end of the study window, the retention rate was [88.8-94.8%] and ULS utilization was [83.9-86.9%] in the three countries analysed. CONCLUSIONS: Similar RT-CGM trends were observed across Germany, Sweden, and the UK. Improvements in hypoglycaemia occurred in all countries. The high retention of users may lead to sustained glycaemic benefits associated with RT-CGM use.

With or Without Residual C-Peptide, Patients with Type 2 Diabetes Realize Glycemic Benefits from Real-Time Continuous Glucose Monitoring.

Real-time continuous glucose monitoring (RT-CGM) is superior to blood glucose monitoring (BGM) for adults with insulin-treated type 2 diabetes (T2D); however, the utility of C-peptide levels for predicting the magnitude of the glycemic benefits is controversial. Data were from a subset of 147 participants in the MOBILE study who were treated with basal-only insulin and who had baseline C-peptide levels ≥0.5 ng/mL. Participants were randomized to treatment with either RT-CGM (n = 100) or BGM (n = 47). Between-group differences in hemoglobin A1c (HbA1c) and time in range (TIR) changes were assessed. The between-group difference in HbA1c favored the RT-CGM group (by 0.58 percentage points, P = 0.004 at 3 months and by 0.42 percentage points, P = 0.04 at 8 months). TIR was 16% higher, and time >180 mg/dL was 16% lower, in the RT-CGM group at 8 months (P = 0.002 for each). In T2D managed with basal insulin, RT-CGM benefits occur for those with residual insulin secretory capacity. Clinical Trial Identifier: NCT03566693.

Sustainable Use of a Real-Time Continuous Glucose Monitoring System from 2018 to 2020.

We aimed to describe patterns of continuous glucose monitoring (CGM) system use and glycemic outcomes from 2018 to 2020 in a large real-world cohort by analyzing anonymized data from US-based CGM users who transitioned from the G5 to the G6 System (Dexcom) in 2018. The main end points were persistent use, within-day and between-day utilization, hypoglycemia, time in range (TIR, 70-180 mg/dL [3.9-10 mmol/L]), and use of the optional calibration feature in 2019 and 2020. In a cohort of 31,034 individuals, rates of persistent use were high, with 27,932 (90.0%) and 26,861 (86.6%) continuing to upload data in 2019 and 2020, respectively. Compared with G5 use, G6 use was associated with higher device utilization, less hypoglycemia, higher TIR (in 2020), and >80% fewer calibrations in both 2019 and 2020 (P's < 0.001). High persistence and utilization of the G6 system may contribute to sustainable glycemic outcomes and decreased user burden.

Accuracy, Utilization, and Effectiveness Comparisons of Different Continuous Glucose Monitoring Systems.

BACKGROUND: Accuracy and feature sets of continuous glucose monitoring (CGM) systems may influence device utilization and outcomes. We compared clinical trial accuracy and real-world utilization and effectiveness of two different CGM systems. MATERIALS AND METHODS: Separately conducted accuracy studies of a fifth-generation and a sixth-generation CGM system involved 50 and 159 adults, respectively. For between-system performance comparisons, propensity score methods were utilized to balance cohort characteristics. Real-world outcomes were assessed in 10,000 anonymized patients who had switched from the fifth-generation to the sixth-generation system and had used connected mobile devices to upload data from both systems, allowing pairwise comparisons of device utilization and glucose concentration distributions. RESULTS: Propensity score-adjusted mean absolute relative differences for the fifth- and sixth-generation systems were 9.0% and 9.9%, and the percentages of values within ±20%/20 mg/dL were 93.1% and 92.5%, respectively. The sixth-generation system, but not the fifth-generation system, met accuracy criteria for interoperable CGM systems. Both systems had high real-world utilization rates (93.8% and 95.3% in the fifth- and sixth-generation systems, respectively). Use of the sixth-generation system was associated with fewer glucose values <55 mg/dL (<3.1 mmol/L) (0.7% vs. 1.1%, P < 0.001) and more values 70-180 mg/dL (3.9-10.0 mmol/L) (57.3% vs. 56.0%, P < 0.001) than the fifth-generation system. CONCLUSIONS: CGM performance outcomes can be compared through the propensity score analysis of clinical trial data and pairwise comparisons of real-world data. The systems compared here had nearly equivalent accuracy and utilization rates. Longer term biochemical and psychosocial benefits observed with the fifth-generation system are also expected with the sixth-generation system.

Performance of a Factory-Calibrated, Real-Time Continuous Glucose Monitoring System in Pediatric Participants With Type 1 Diabetes.

BACKGROUND: The perceived value and consistent use of continuous glucose monitoring (CGM) systems depends in part on their accuracy. We assessed the performance of a sixth-generation CGM system (Dexcom G6) in children and adolescents. METHODS: Forty-nine participants (6-17 years of age, mean ± SD of 13.5 ± 3.3 years), all with type 1 diabetes, enrolled and data were available from 37. Each participant wore 1 sensor for up to 10 days and was asked to undergo an in-clinic visit lasting 6-12 hours for frequent blood glucose (BG) sample testing on one of the sensor wear days. Estimated glucose values (EGVs) from the G6 system were compared with venous BG values measured with a laboratory reference instrument (YSI). RESULTS: The overall mean absolute relative difference (MARD) for 1387 EGV-YSI pairs was 7.7%, and the overall percentage of EGVs within 20% or 20 mg/dL of the YSI reference value (for YSI > or ⩽100 mg/dL, respectively, the "%20/20") was 96.2%. The %20/20 was 92.1% on Day 1 and 91.0% on Day 10 of sensor wear. For EGVs <70 mg/dL, 92.6% of the YSI values were within 20 mg/dL and for EGVs >250 mg/dL, 100% of the YSI values were within 20%. Differences between EGVs and YSI values in over 99.9% of the pairs posed no or only slight clinical risk as evaluated by surveillance error grid analysis. CONCLUSIONS: The accuracy of the G6 CGM system in pediatrics may encourage consistent use of the system and contribute to improved glycemic outcomes in this population.

The Effect of Reduced Self-Monitored Blood Glucose Testing After Adoption of Continuous Glucose Monitoring on Hemoglobin A1c and Time in Range.

The effectiveness of real-time continuous glucose monitoring (rtCGM) in adults with diabetes treated with insulin injections was evaluated in the 24-week DIAMOND clinical trial comparing rtCGM users to a control group using self-monitored blood glucose (SMBG) testing ( Clinicaltrials.gov : NCT02282397). All participants were instructed to use SMBG results for diabetes management decisions; however, SMBG testing frequency varied within the rtCGM group. This brief report evaluated how SMBG frequency changes in the rtCGM group were correlated with glycemic outcomes in the same trial. Baseline and end-of-study hemoglobin A1c (HbA1c) levels, percentages of CGM values in the 70-180 mg/dL target range (time in range [TIR]), mean of daily differences (MODD), and glycemic coefficients of variation (CVs) were compared. The rtCGM group analyzed included 175 participants-99 with type 1 diabetes (T1D) and 76 with type 2 diabetes (T2D). When comparing participants whose SMBG testing frequency decreased by >1/day versus ≤1/day, mean change in HbA1c was similar (-0.9 ± 0.7 percentage points in both groups, P = 0.59), as was change in TIR (+3.9 ± 14.3 vs. +5.7 ± 13.7 percentage points, respectively, P = 0.39). Likewise, when comparing participants in the highest and lowest quartiles of SMBG frequency reduction (≥2.2 vs. ≤0.4 fewer tests/day, respectively), changes in HbA1c (-0.8 ± 0.6 vs. -0.9 ± 0.6 percentage points, respectively, P = 0.52) and TIR (+4.8 ± 13.2 vs. +5.6 ± 12.7 percentage points, respectively, P = 0.98) were similar. The mean (standard deviation [SD]) change in MODD was -8.3 mg/dL (14.8) and -5.5 mg/dL (14.7) for participants who reduced their SMBG frequency by >1 test/day and ≤1 test/day, respectively; the mean (SD) change in CV was -3.6% (5.0) and -1.6% (5.1) for participants who reduced their SMBG frequency by >1 test/day and ≤1 test/day, respectively. These findings suggest that individuals who decrease the frequency of SMBG testing can effectively base some of their diabetes-related treatment decisions on glucose concentrations, trend information, and alarms provided by their rtCGM systems.

Continuous glucose monitors: use of waveform versus glycemic values in the improvements of glucose control, quality of life, and fear of hypoglycemia.

How patients are benefitting from continuous glucose monitoring (CGM) remains poorly understood. The focus on numerical glucose values persists, even though access to the glucose waveform and rate of change may contribute more to improved control. This pilot study compared outcomes of patients using CGMs with or without access to the numerical values on their CGM. Ten persons with type 1 diabetes, naïve to CGM use, enrolled in a 12-week study. Subjects were randomly assigned to either unmodified CGM receivers, or to CGM receivers that had their numerical values obscured but otherwise functioned normally. HbA1c, quality of life (QLI-D), and fear of hypoglycemia (HFS) were assessed, at baseline and at week 12. Baseline HbA1c for the entire group was 7.46 ± 1.27%. At week 12 the experimental group HbA1c reduction was 1.5 ± 0.9% (p < .05), the control group's reduction was 0.06 ± 0.61% (p > .05). Repeated measures testing revealed no significant difference in HbA1c reduction between groups. Both groups had reductions in HFS; these reductions were statistically significant within groups (p < .05), but not between groups. QLI-D indices demonstrated improvements (p < .05) in QLI-D total and the health and family subscales, but not between groups. The results of this pilot study suggest that benefits of CGM extend beyond reductions in HbA1c to reductions in fear of hypoglycemia and improvements in quality of life. The display of a numerical glucose value did not improve control when compared to numerically blinded units.