Dexcom G6 Continuous Glucose Monitoring Research Articles

Accuracy of Real Time Continuous Glucose Monitoring during Different Liquid Solution Challenges in Healthy Adults: A Randomized Controlled Cross-Over Trial.

Continuous glucose monitoring (CGM) represents an integral of modern diabetes management, however, there is still a lack of sensor performance data when rapidly consuming different liquids and thus changing total body water. 18 healthy adults (ten females, age: 23.1 ± 1.8 years, BMI 22.2 ± 2.1 kg·m−2) performed four trial visits consisting of oral ingestion (12 mL per kg body mass) of either a 0.9% sodium chloride, 5% glucose or Ringer’s solution and a control visit, in which no liquid was administered (control). Sensor glucose levels (Dexcom G6, Dexcom Inc., San Diego, CA, USA) were obtained at rest and in 10-min intervals for a period of 120 min after solution consumption and compared against reference capillary blood glucose measurements. The overall MedARD [IQR] was 7.1% [3.3–10.8]; during control 5.9% [2.7–10.8], sodium chloride 5.0% [2.7–10.2], 5% glucose 11.0% [5.3–21.6] and Ringer’s 7.5% [3.1–13.2] (p < 0.0001). The overall bias [95% LoA] was 4.3 mg·dL−1 [−19 to 28]; during control 3.9 mg·dL−1 [−11 to 18], sodium chloride 4.8 mg·dL−1 [−9 to 19], 5% glucose 3.6 mg·dL−1 [−33 to 41] and Ringer’s solution 4.9 mg·dL−1 [−13 to 23]. The Dexcom G6 CGM system detects glucose with very good accuracy during liquid solution challenges in normoglycemic individuals, however, our data suggest that in people without diabetes, sensor performance is influenced by different solutions.

Hypoglycemia in Prospective Multicenter Study of Pregnancies with Pre-Existing Type 1 Diabetes on Sensor-Augmented Pump Therapy: The LOIS-P Study.

Background: Pregnancies in type 1 diabetes are high risk, and data in the United States are limited regarding continuous glucose monitoring (CGM)-based hypoglycemia throughout pregnancy while on sensor-augmented insulin pump therapy. Materials and Methods: Pregnant women with type 1 diabetes in the LOIS-P Study (Longitudinal Observation of Insulin use and glucose Sensor metrics in Pregnant women with type 1 diabetes using continuous glucose monitors and insulin pumps) were enrolled before 17 weeks gestation at three U.S. centers and we used their personal insulin pump and a study Dexcom G6 CGM. We analyzed data of 25 pregnant women for CGM hypoglycemia based on international consensus guidelines for percentage time <63 and 54 mg/dL, hypoglycemic events and prolonged hypoglycemia events for 24-h, daytime, and overnight periods, and severe hypoglycemia (SH) episodes. Results: For a 24-h period, biweekly median percentage of time <63 mg/dL ranged from 0.8% at biweek 4-5 to 3.7% at biweek 14-15 with high variability throughout pregnancy. Median percentage of time <63 and 54 mg/dL was higher overnight than daytime (P < 0.01). Hypoglycemic events occurred throughout the pregnancy, ranged 1-4 events per 2 weeks, significantly decreased after the 20th week, and occurred predominantly during daytime (P < 0.01). For overnight period, hypoglycemia and events were more concentrated from 12 to 3 am. Seven prolonged hypoglycemia events without any associated SH occurred in four participants (16%), primarily overnight. Three participants experienced a single episode of SH. Conclusions: Our results suggest a higher overall risk of hypoglycemia throughout pregnancy during the overnight period with continued daytime risk of hypoglycemic events in pregnancies complicated by type 1 diabetes.

Protocol for a feasibility randomised control trial for continuous glucose monitoring in patients with type 1 diabetes at first-level hospitals in rural Malawi

IntroductionThe majority of people living with type 1 diabetes (PLWT1D) struggle to access high-quality care in low-income countries (LICs), and lack access to technologies, including continuous glucose monitoring (CGM), that...

Clustering of Hypoglycemia Events in Patients With Hyperinsulinism: Extension of the Digital Phenotype Through Retrospective Data Analysis.

BackgroundHyperinsulinism (HI) due to excess and dysregulated insulin secretion is the most common cause of severe and recurrent hypoglycemia in childhood. High cerebral glucose use in the early hours results in a high risk of hypoglycemia in people with diabetes and carries a significant risk of brain injury. Prevention of hypoglycemia is the cornerstone of the management of HI, but the risk of hypoglycemia at night or the timing of hypoglycemia in children with HI has not been studied; thus, the digital phenotype remains incomplete and management suboptimal.ObjectiveThis study aims to quantify the timing of hypoglycemia in patients with HI to describe glycemic variability and to extend the digital phenotype. This will facilitate future work using computational modeling to enable behavior change and reduce exposure of patients with HI to injurious hypoglycemic events.MethodsPatients underwent continuous glucose monitoring (CGM) with a Dexcom G4 or G6 CGM device as part of their clinical assessment for either HI (N=23) or idiopathic ketotic hypoglycemia (IKH; N=24). The CGM data were analyzed for temporal trends. Hypoglycemia was defined as glucose levels <3.5 mmol/L.ResultsA total of 449 hypoglycemic events totaling 15,610 minutes were captured over 237 days from 47 patients (29 males; mean age 70 months, SD 53). The mean length of hypoglycemic events was 35 minutes. There was a clear tendency for hypoglycemia in the early hours (3-7 AM), particularly for patients with HI older than 10 months who experienced hypoglycemia 7.6% (1480/19,370 minutes) of time in this period compared with 2.6% (2405/92,840 minutes) of time outside this period (P<.001). This tendency was less pronounced in patients with HI who were younger than 10 months, patients with a negative genetic test result, and patients with IKH. Despite real-time CGM, there were 42 hypoglycemic events from 13 separate patients with HI lasting >30 minutes.ConclusionsThis is the first study to have taken the first step in extending the digital phenotype of HI by describing the glycemic trends and identifying the timing of hypoglycemia measured by CGM. We have identified the early hours as a time of high hypoglycemia risk for patients with HI and demonstrated that simple provision of CGM data to patients is not sufficient to eliminate hypoglycemia. Future work in HI should concentrate on the early hours as a period of high risk for hypoglycemia and must target personalized hypoglycemia predictions. Focus must move to the human-computer interaction as an aspect of the digital phenotype that is susceptible to change rather than simple mathematical modeling to produce small improvements in hypoglycemia prediction accuracy.

Use of factory-calibrated real-time continuous glucose monitoring improves time in target and HbA1c in a multiethnic cohort of adolescents and young adults with type 1 diabetes: the MILLENNIALS study

OBJECTIVE International type 1 diabetes registries have shown that HbA1c levels are highest in young people with type 1 diabetes; however, improving their glycemic control remains a challenge. We propose that use of the factory-calibrated Dexcom G6 CGM system would improve glycemic control in this cohort. RESEARCH DESIGN AND METHODS We conducted a randomized crossover trial in young people with type 1 diabetes (16–24 years old) comparing the Dexcom G6 CGM system and self-monitoring of blood glucose (SMBG). Participants were assigned to the interventions in random order during two 8-week study periods. During SMBG, blinded continuous glucose monitoring (CGM) was worn by each participant for 10 days at the start, week 4, and week 7 of the control period. HbA1c measurements were drawn after enrollment and before and after each treatment period. The primary outcome was time in range 70–180 mg/dL. RESULTS Time in range was significantly higher during CGM compared with control (35.7 ± 13.5% vs. 24.6 ± 9.3%; mean difference 11.1% [95% CI 7.0–15.2]; P CONCLUSIONS CGM use in young people with type 1 diabetes improves time in target and HbA1c levels compared with SMBG.

Accuracy of Dexcom G6 Continuous Glucose Monitoring in Non-Critically Ill Hospitalized Patients With Diabetes.

OBJECTIVEAdvances in continuous glucose monitoring (CGM) have transformed ambulatory diabetes management. Until recently, inpatient use of CGM has remained investigational, with limited data on its accuracy in the hospital setting.RESEARCH DESIGN AND METHODSTo analyze the accuracy of Dexcom G6, we compared retrospective matched-pair CGM and capillary point-of-care (POC) glucose data from three inpatient CGM studies (two interventional and one observational) in general medicine and surgery patients with diabetes treated with insulin. Analysis of accuracy metrics included mean absolute relative difference (MARD), median absolute relative difference (ARD), and proportion of CGM values within 15, 20, and 30% or 15, 20, and 30 mg/dL of POC reference values for blood glucose >100 mg/dL or ≤100 mg/dL, respectively (% 15/15, % 20/20, % 30/30). Clinical reliability was assessed with Clarke error grid (CEG) analyses.RESULTSA total of 218 patients were included (96% with type 2 diabetes) with a mean age of 60.6 ± 12 years. The overall MARD (n = 4,067 matched glucose pairs) was 12.8%, and median ARD was 10.1% (interquartile range 4.6, 17.6]. The proportions of readings meeting % 15/15, % 20/20, and % 30/30 criteria were 68.7, 81.7, and 93.8%, respectively. CEG analysis showed 98.7% of all values in zones A and B. MARD and median ARD were higher in the case of hypoglycemia (<70 mg/dL) and severe anemia (hemoglobin <7 g/dL).CONCLUSIONSOur results indicate that CGM technology is a reliable tool for hospital use and may help improve glucose monitoring in non–critically ill hospitalized patients with diabetes.

619-P: Comparison of Dexcom G6 Continuous Glucose Monitoring and Point-of-Care Blood Glucose Testing in Hospitalized Patients with Diabetes

This prospective observational study compared the performance of the Dexcom G6 continuous glucose monitor (CGM) and point-of-care (POC) blood glucose (BG) testing in a non-ICU setting. Methods: We placed a blinded Dexcom G6 on 91 insulin-treated adult medicine and surgery patients (age 57±10 years, BMI 35±10 kg/m2, HbA1c 9.2±2.1%), with a median hospital length of stay of 8.0 days (min, max 2.0, 33.0), and total daily insulin dose of 45±29 U/day, to compare inpatient glycemic control metrics as measured by POC and CGM. Results: CGM mean absolute relative difference (MARD) was 12.5% with 98.9% of glucose values falling into Clark Error Grid zone A or B for matched POC and CGM glucose pairs. Compared to POC, a greater percentage of patients were identified by CGM to have hypoglycemia 2 hours (5.6% vs. 0%) and severe hyperglycemia >250 mg/dl (73% vs. 66%). Differences in glycemic metrics between POC and CGM are shown in the Table. Conclusion: Dexcom G6 detected more overall, nocturnal and prolonged hypoglycemia in hospitalized non-ICU patients with diabetes than POC testing. Future prospective studies are needed to determine the benefits of real-time CGM in improving inpatient diabetes care and in reducing hypoglycemia and hyperglycemia in hospitalized patients with diabetes. Disclosure G. M. Davis: None. P. Vellanki: Consultant; Self; Boehringer Ingelheim Pharmaceuticals, Inc. F. J. Pasquel: Consultant; Self; Boehringer Ingelheim Pharmaceuticals, Inc., Research Support; Self; Dexcom, Inc., Merck & Co., Inc. L. Peng: None. G. E. Umpierrez: Research Support; Self; AstraZeneca, Dexcom, Inc., Novo Nordisk. A. Migdal: None. M. A. Urrutia: None. K. Zamudio-coronado: None. M. C. Perez-guzman: None. B. S. Albury: None. S. Cardona: None. R. J. Galindo: Consultant; Self; Abbott Diabetes, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Novo Nordisk, Sanofi US, Valeritas, Inc., Research Support; Self; Dexcom, Inc., Novo Nordisk. T. Idrees: None. Funding Dexcom, Inc.

609-P: Comparison of Dexcom G6 Continuous Glucose Monitoring Performance between Abdomen and Upper Arm Placement in Hospitalized Patients with Diabetes

Dexcom G6 is a continuous glucose monitoring (CGM) device FDA approved for use on the abdomen in adults and children ±2 years. Comparative data of Dexcom G6 placed in the upper arm and abdomen in hospitalized patients has not been reported. Accordingly, we conducted a prospective study evaluating Dexcom G6 in the abdomen and upper arm in 91 insulin treated adult medicine and surgery patients (age 57±10 years, BMI 35±10, HbA1c 9.2±2.1%), with hospital length of stay of 8.0 (min, max 2.0, 33.0) days, and mean total insulin dose of 45±29 U/day. Study end points included differences between insertion sites on mean daily blood glucose, time in target range (70-180 mg/dl), time below range (<70 and <54 mg/dl), time above range (>180 and >250 mg/dl), glycemic variability and proportion of patients with nocturnal and prolonged hypoglycemia. We found a good concordance correlation coefficient between arm and abdomen of 0.915 (95% CI: 0.907, 0.923).Conclusion: Our results indicate no clinically significant differences in glycemic metrics between Dexcom G6 CGM placed in the abdomen and upper arm in hospitalized patients with diabetes.View largeDownload slideView largeDownload slide DisclosureA. Migdal: None. M. Fayfman: None. S. Cardona: None. I. A. Castro-revoredo: None. F. J. Pasquel: Consultant; Self; Boehringer Ingelheim Pharmaceuticals, Inc., Research Support; Self; Dexcom, Inc., Merck & Co., Inc. L. Peng: None. G. E. Umpierrez: Research Support; Self; AstraZeneca, Dexcom, Inc., Novo Nordisk. K. W. Zamudio: None. M. C. Perez-guzman: None. T. Idrees: None. B. S. Albury: None. G. Davis: None. M. A. Urrutia: None. R. J. Galindo: Consultant; Self; Abbott Diabetes, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Novo Nordisk, Sanofi US, Valeritas, Inc., Research Support; Self; Dexcom, Inc., Novo Nordisk. P. Vellanki: Consultant; Self; Boehringer Ingelheim Pharmaceuticals, Inc.FundingDexcom, Inc.

613-P: Performance Evaluation of Dexcom G6 Continuous Glucose Monitoring and Capillary Blood Glucose after Hospital Discharge in Patients with Diabetes

The efficacy of continuous glucose monitoring (CGM) after hospital discharge in patients with diabetes (DM) has not been established. This prospective pilot study compared glycemic outcomes between capillary blood glucose (CBG) and CGM after hospital discharge. At discharge, a blinded Dexcom G6 CGM was inserted in 82 patients with DM. Patients were asked to perform CBG testing (3-4/d) and to return the CBG logs and CGM device after 10 days of discharge. Patients were treated with insulin ± oral antidiabetic agents and followed by their primary care team. A total of 65 patients (73.3%) returned their CGM and were included (age 58.3±11 years, 56% Males, HbA1c 8.7±2%, 98% DM2). Only 42 patients (51.2%) returned CBG logs (mean 3.01±0.9 CBG/d). CGM detection of hypoglycemia Disclosure R. J. Galindo: Consultant; Self; Abbott Diabetes, Boehringer Ingelheim International GmbH, Eli Lilly and Company, Novo Nordisk, Sanofi US, Valeritas, Inc., Research Support; Self; Dexcom, Inc., Novo Nordisk. M. C. Perez-guzman: None. S. Cardona: None. F. J. Pasquel: Consultant; Self; Boehringer Ingelheim Pharmaceuticals, Inc., Research Support; Self; Dexcom, Inc., Merck & Co., Inc. L. Peng: None. G. E. Umpierrez: Research Support; Self; AstraZeneca, Dexcom, Inc., Novo Nordisk. G. Davis: None. T. Idrees: None. M. A. Urrutia: None. K. W. Zamudio: None. B. S. Albury: None. A. Migdal: None. P. Vellanki: Consultant; Self; Boehringer Ingelheim Pharmaceuticals, Inc. M. Fayfman: None. Funding Dexcom, Inc.

900-P: Continuous Glucose Monitoring in Youth with Type 2 Diabetes: A Pilot and Feasibility Study

Objective: Real-time continuous glucose monitoring (CGM) is effective for diabetes management in T1D and adults with T2D, but has not been assessed in youth with T2D. The objective of this study was to assess the feasibility and acceptability of CGM use in youth with T2D. Methods: Youth (13- 21 years old) with T2D ≥ 6 months and A1c &amp;gt; 7%, on any FDA approved treatment regimen were included. After a blinded run-in period, participants were given a Dexcom G6 CGM system for 12 weeks. The use and acceptability of the real-time CGM were evaluated by sensor usage, surveys, and focus group qualitative data. Results: Youth (n=8) had median age 19.4 (IQR 15.5-20.6) years, were 75% female, 50% hispanic/latino ethnicity, 50% non-English speaking at home, and 91% had public insurance. Baseline A1c was 11.7 (±2.8)% with mean diabetes duration of 2.5 (IQR 1.4 - 5.1) years and 75% were on basal insulin. Of the 7 participants who have completed the CGM intervention, all reported CGM was a positive experience (50% very positive, 50% slightly positive), easy to use (50% very easy, 50% easy), and useful (83% useful, 17% useful). All participants desired to continue to use real-time CGM in the future. 85% were “extremely” likely to recommend real-time CGM to friends. 67% of participants self-reported eating fewer meals while using CGM. All participants used sensors for the duration of the study. Conclusion: Real-time CGM is feasible and acceptable for youth with type 2 diabetes. Larger randomized controlled trials are needed to assess effects on glycemic control, healthy lifestyle changes, and diabetes distress. Disclosure H. Chesser: None. S. Srinivasan: None. J. C. Wong: Advisory Panel; Self; Provention Bio, Inc., Research Support; Self; Dexcom, Inc., Tandem Diabetes Care.

Association between attendance at an American diabetes camp and improvements in glycaemic control and treatment satisfaction.

IntroductionFew studies have evaluated glycaemic control using continuous glucose monitoring (CGM) in individuals before and after attendance at a diabetes camp or by comparing control groups at home to control groups at camp.MethodsYouth (6–17 years) with T1D and receiving insulin therapy were enrolled at a week‐long diabetes camp. They participated in three clinic visits: at the start of a week at home, by initiating a Dexcom G6 CGM system; at the start of a week at camp, where the home week G6 was removed and a camp week G6 was inserted; and after camp, where the camp week G6 was removed. We administered Problem Areas in Diabetes (PAID) surveys at the second and third visits. Participants with <80% CGM data coverage or who did not complete all PAID surveys were excluded from analysis. We compared glycaemic control and PAID scores between the week at home and week at camp.ResultsOf 76 enrolled campers, 69 completed the study and 52 had results that qualified for analysis. The mean participant age was 12.5 ± 2.2 years. Camp was associated with significantly improved treatment satisfaction, time in desired glucose range and insulin sensitivity. Time in hyperglycaemia and basal insulin requirements decreased significantly.ConclusionsDiabetes camp is associated with significant improvements in diabetes treatment satisfaction and glycaemic control compared to home care.

Continuous Glucose Monitoring in the Intensive Care Unit Following Total Pancreatectomy with Islet Autotransplantation in Children: Establishing Accuracy of the Dexcom G6 Model.

Hyperglycemia is detrimental to postoperative islet cell survival in patients undergoing total pancreatectomy with islet autotransplantation (TPIAT). This makes continuous glucose monitoring (CGM) a useful management tool. We evaluated the accuracy of the Dexcom G6 CGM in pediatric intensive care unit patients following TPIAT. Twenty-five patients who underwent TPIAT had Dexcom G6 glucose values compared to paired serum glucose values. All paired glucose samples were obtained within 5 minutes of each other during the first seven days post TPIAT. Data were evaluated using mean absolute difference (MAD), mean absolute relative difference (MARD), %20/20, %15/15 accuracy, and Clarke Error Grid analysis. Exclusions included analysis during the CGM “warm-up” period and hydroxyurea administration (known drug interference). A total of 183 time-matched samples were reviewed during postoperative days 2–7. MAD was 14.7 mg/dL and MARD was 13.4%, with values of 15.2%, 14.0%, 12.1%, 11.4%, 13.2% and 14.1% at days 2, 3, 4, 5, 6 and 7, respectively. Dexcom G6 had a %20/20 accuracy of 78%, and a %15/15 accuracy of 64%. Clarke Error Grid analysis showed that 77% of time-matched values were clinically accurate, and 100% were clinically acceptable. The Dexcom G6 CGM may be an accurate tool producing clinically acceptable values to make reliable clinical decisions in the immediate post-TPIAT period.

Early use of continuous glucose monitoring in children and adolescents after total pancreatectomy with islet autotransplantation.

Children undergoing total pancreatectomy with islet autotransplantation (TPIAT) for chronic pancreatitis require intensive insulin therapy early after TPIAT with narrow glycemic targets, which can a present significant care burden. Outpatient use of continuous glucose monitoring (CGM) systems by children and caregivers early after TPIAT is inadequately studied. In this open-label study, we randomized 14 children and adolescents (mean age 15.4 years) after hospital discharge for TPIAT to Dexcom G6 CGM (n = 7) or standard care with a glucometer (n = 7) to assess acceptability and glycemic control with use of CGM versus usual care (glucometer). Participants in the control arm also wore a blinded CGM for 1 week. Children randomized to real-time CGM had lower mean sensor glucose values compared with controls (p = 0.002), and high overall satisfaction with CGM. Our data indicate that CGM is a useful adjunct to diabetes management for children who have recently undergone TPIAT.

Performance of the Dexcom G6 Continuous Glucose Monitoring System in Pregnant Women with Diabetes.

Background: The aim of this study was to determine the performance of the Dexcom G6 continuous glucose monitoring (CGM) system across three sensor wear sites in pregnant women with diabetes in the second or third trimesters.Methods: Participants with type 1 (T1D), type 2 (T2D), or gestational (GDM) diabetes mellitus were enrolled at three sites. Each wore two G6 sensors on the abdomen, upper buttock, and/or posterior upper arm for 10 days and underwent a 6-h clinic session between days 3 and 7 of sensor wear, during which YSI reference blood glucose values were obtained every 30 min. No intentional glucose manipulations were performed. Accuracy metrics included the proportion of CGM values that were within ±20% of paired reference values >100 mg/dL or ±20 mg/dL of YSI values ≤100 mg/dL (hereafter referred to as %20/20), as well as the analogous %15/15, %30/30, and %40/40. The mean absolute relative difference (MARD) between CGM-YSI pairs was also calculated.Results: Thirty-two participants with T1D (n = 20), T2D (n = 3), or GDM (n = 9) were enrolled: 19 were in the second trimester and 13 were in the third trimester of pregnancy. Compared with the reference, 92.5% of CGM values were within ±20%/20 mg/dL. The overall MARD and that of sensors worn on the abdomen, upper buttock, and posterior upper arm was 10.3%, 11.5%, 11.2%, and 8.7%, respectively. There were no device-related adverse events. Skin reactions at the insertion sites were absent or minor.Conclusions: The Dexcom G6 CGM system is accurate and safe in pregnant women with diabetes.

Continuous Glucose Monitoring in Critically Ill Patients With COVID-19: Results of an Emergent Pilot Study.

Amidst the coronavirus disease 2019 (COVID-19) pandemic, continuous glucose monitoring (CGM) has emerged as an alternative for inpatient point-of-care blood glucose (POC-BG) monitoring. We performed a feasibility pilot study using CGM in critically ill patients with COVID-19 in the intensive care unit (ICU). Single-center, retrospective study of glucose monitoring in critically ill patients with COVID-19 on insulin therapy using Medtronic Guardian Connect and Dexcom G6 CGM systems. Primary outcomes were feasibility and accuracy for trending POC-BG. Secondary outcomes included reliability and nurse acceptance. Sensor glucose (SG) was used for trends between POC-BG with nursing guidance to reduce POC-BG frequency from one to two hours to four hours when the SG was in the target range. Mean absolute relative difference (MARD), Clarke error grids analysis (EGA), and Bland-Altman (B&A) plots were calculated for accuracy of paired SG and POC-BG measurements. CGM devices were placed on 11 patients: Medtronic (n = 6) and Dexcom G6 (n = 5). Both systems were feasible and reliable with good nurse acceptance. To determine accuracy, 437 paired SG and POC-BG readings were analyzed. For Medtronic, the MARD was 13.1% with 100% of readings in zones A and B on Clarke EGA. For Dexcom, MARD was 11.1% with 98% of readings in zones A and B. B&A plots had a mean bias of -17.76 mg/dL (Medtronic) and -1.94 mg/dL (Dexcom), with wide 95% limits of agreement. During the COVID-19 pandemic, CGM is feasible in critically ill patients and has acceptable accuracy to identify trends and guide intermittent blood glucose monitoring with insulin therapy.

Accuracy of the Dexcom G6 Glucose Sensor during Aerobic, Resistance, and Interval Exercise in Adults with Type 1 Diabetes.

The accuracy of continuous glucose monitoring (CGM) sensors may be significantly impacted by exercise. We evaluated the impact of three different types of exercise on the accuracy of the Dexcom G6 sensor. Twenty-four adults with type 1 diabetes on multiple daily injections wore a G6 sensor. Participants were randomized to aerobic, resistance, or high intensity interval training (HIIT) exercise. Each participant completed two in-clinic 30-min exercise sessions. The sensors were applied on average 5.3 days prior to the in-clinic visits (range 0.6–9.9). Capillary blood glucose (CBG) measurements with a Contour Next meter were performed before and after exercise as well as every 10 min during exercise. No CGM calibrations were performed. The median absolute relative difference (MARD) and median relative difference (MRD) of the CGM as compared with the reference CBG did not differ significantly from the start of exercise to the end exercise across all exercise types (ranges for aerobic MARD: 8.9 to 13.9% and MRD: −6.4 to 0.5%, resistance MARD: 7.7 to 14.5% and MRD: −8.3 to −2.9%, HIIT MARD: 12.1 to 16.8% and MRD: −14.3 to −9.1%). The accuracy of the no-calibration Dexcom G6 CGM was not significantly impacted by aerobic, resistance, or HIIT exercise.

Use of Factory-Calibrated Real-time Continuous Glucose Monitoring Improves Time in Target and HbA1c in a Multiethnic Cohort of Adolescents and Young Adults With Type 1 Diabetes: The MILLENNIALS Study.

International type 1 diabetes registries have shown that HbA1c levels are highest in young people with type 1 diabetes; however, improving their glycemic control remains a challenge. We propose that use of the factory-calibrated Dexcom G6 CGM system would improve glycemic control in this cohort. We conducted a randomized crossover trial in young people with type 1 diabetes (16-24 years old) comparing the Dexcom G6 CGM system and self-monitoring of blood glucose (SMBG). Participants were assigned to the interventions in random order during two 8-week study periods. During SMBG, blinded continuous glucose monitoring (CGM) was worn by each participant for 10 days at the start, week 4, and week 7 of the control period. HbA1c measurements were drawn after enrollment and before and after each treatment period. The primary outcome was time in range 70-180 mg/dL. Time in range was significantly higher during CGM compared with control (35.7 ± 13.5% vs. 24.6 ± 9.3%; mean difference 11.1% [95% CI 7.0-15.2]; P < 0.001). CGM use reduced mean sensor glucose (219.7 ± 37.6 mg/dL vs. 251.9 ± 36.3 mg/dL; mean difference -32.2 mg/dL [95% CI -44.5 to -20.0]; P < 0.001) and time above range (61.7 ± 15.1% vs. 73.6 ± 10.4%; mean difference 11.9% [95% CI -16.4 to -7.4]; P < 0.001). HbA1c level was reduced by 0.76% (95% CI -1.1 to -0.4) (-8.5 mmol/mol [95% CI -12.4 to -4.6]; P < 0.001). Times spent below range (<70 mg/dL and <54 mg/dL) were low and comparable during both study periods. Sensor wear was 84% during the CGM period. CGM use in young people with type 1 diabetes improves time in target and HbA1c levels compared with SMBG.

76-LB: Differences in Time-In-Range, Glycemic Variability, and the Glucose Management Indicator in Pregnant Women with Type 1 (T1D), Type 2 (T2D), and Gestational Diabetes (GDM)

Glycemic control varies among different cohorts of pregnant women with diabetes. Most studies examining differences between groups using continuous glucose monitoring (CGM) data were performed with older CGM systems worn for 2-7 days. We examined differences in glycemic control and glycemic variability (GV) between pregnant women (n=32) with T1D (n=20), T2D (n=3), or GDM (n=9) in the 2nd and 3rd trimesters using the Dexcom G6 CGM system, worn for 10 days as part of a pregnancy CGM accuracy trial. Pair-wise comparisons were made between groups and group heterogeneity testing was performed. No adjustments were made for multiple comparisons analyses. Most women required insulin therapy (26/32, 81%). The baseline HbA1C levels were similar between groups (Table). The glucose management indicator (GMI) was numerically similar to HbA1C for the T1D and GDM cohorts. Time spent &amp;gt;140 mg/dL (p=0.009) was highest and time in range (63-140 mg/dL) was lowest (p=0.001) in women with T1D compared to the other groups. The coefficient of variation (CV) and mean amplitude of glycemic excursions (MAGE) were highest in the T1D group, lowest in the GDM group, and intermediate in the T2D group (p&amp;lt;0.0001 for each). Glycemic control was better and GV was lower for pregnant women with T2D and GDM compared to women with T1D. CGM use in pregnancy helps elucidate GV. Disclosure S. Polsky: None. C.J. Levy: Consultant; Self; Dexcom, Inc. Employee; Spouse/Partner; Allergan plc. Research Support; Self; Abbott, Dexcom, Inc., Insulet Corporation. X. Zhang: Employee; Self; Dexcom, Inc. S. Shah: Employee; Self; Dexcom, Inc. G. Haroush: None. K. Nelson: None. G. O’Malley: Research Support; Self; Abbott, Dexcom, Inc. S.J. Ogyaadu: None. S.J. Brackett: None. C. Levister: None. K.N. Castorino: Research Support; Self; Abbott, Dexcom, Inc., Medtronic, Mylan, Novo Nordisk Inc. Funding Dexcom, Inc.

86-LB: Accuracy of a Factory-Calibrated, Real-Time Continuous Glucose Monitoring (CGM) System during Elective Abdominal Surgery

Aim: To assess the accuracy of the Dexcom G6 CGM system during elective abdominal surgery. Methods: Twenty adults with (pre-)diabetes scheduled for abdominal surgery (&amp;gt;2h) (5 females, age 69±13 yrs, BMI 27.3±6.6 kg/m2, HbA1c 7.0±1.3%) wore the Dexcom G6 sensor from 7±2 days preoperatively until hospital discharge. Reference capillary glucose values were obtained every 20min from induction of anaesthesia until 2h post-surgery using the Accu-Chek® Inform II meter. The primary endpoint was the mean absolute relative difference (ARD) between sensor and reference method. Results: Mean±SD operating time was 306±170min and included pancreas/liver (45%), upper GI (10%), lower GI (40%) and kidney (5%) surgeries. The mean±SD and median [interquartile range] ARD of 523 paired CGM/reference values were 12.7±8.7% and 10.4% [4.3%, 19.7%], respectively. A total of 99.4% pairs were in Clarke error grid Zones A or B (A, 76.5%, B 22.9%, Figure 1). Overall, 65.8% of sensor readings were within the limits specified by the ISO 15197:2013 norm. Sensor readings were available for 98.6% [95.9%, 100%] of the perioperative time. Intraoperative sensor replacement was required in one instance. There were no adverse device effects. Conclusion: Perioperative use of the Dexcom G6 system showed satisfying accuracy, opening new avenues for perioperative diabetes care. Disclosure A. Tripyla: None. D. Herzig: None. C. Nakas: None. J. Dehais: None. A. Andreou: None. F. Amiet: None. B. Gloor: None. A. Vogt: None. L. Bally: None. Funding Dexcom, Inc. (HOS-2019-005)

823-P: Diabetes Camp Experience Associated with Improved Glycemia and Treatment Satisfaction

We compared glycemic metrics using continuous glucose monitoring (CGM) and quality of life between diabetes camp and the preceding home week. Insulin-treated youth (6-17 years) with T1D were enrolled at Barton Diabetes Camp and participated in 3 clinic visits: at the start of home week, where a Dexcom G6 CGM system was initialized; at the start of camp week, where the home week G6 was removed and a camp week G6 was inserted; and after camp, where the camp week G6 was removed. Problem areas in diabetes (PAID) surveys were administered at visits 2 and 3. Data from campers who did not complete all surveys were excluded. At camp, treatment decisions were informed by G6 as per FDA guidelines; interventions were prompted by daytime glucose levels ≤55 mg/dL or ≥350 mg/dL and for nighttime glucose levels ≤80 mg/dL or ≥300 mg/dL. Glycemic control and PAID scores were compared between home and camp weeks. Of 76 enrolled campers, 69 completed the study and 52 had results that qualified for analysis. Mean (SD) age was 12.5 (2.2) years. Most campers used insulin pumps (87.2%) and had experience with CGM (86.6%). Camp was associated with significant improvements in treatment satisfaction, time in range and in hyperglycemia, decreased basal insulin requirements, and improved insulin sensitivity (Table). Diabetes camp is associated with significant improvements in diabetes treatment satisfaction and glycemia compared to home care. Disclosure A. Darukhanavala: None. K.V. Dinunno: None. S. Puhr: Employee; Self; Dexcom, Inc. J.B. Welsh: Employee; Self; CSL Behring. L. Butler: None. D. Alfego: None. K.L. Magyar: None. Funding Dexcom, Inc.