A trio of studies presented at ATTD 2023 detail the strengths and limitations of real-time continuous glucose monitoring technologies in an array of patient populations and settings.
If the US rollout of the Dexcom G7 beginning a week prior was not enough to place the technology in the spotlight at the 16th annual conference on Advanced Technologies & Treatments for Diabetes (ATTD 2023), the company’s presence could be felt throughout the conference through spotlights in symposiums, presentations, and poster sessions as well as with signage throughout the conference center.
“Last year at ATTD we first introduced our expanded portfolio of Dexcom CGM systems,” said Jake Leach, executive vice president and chief operating officer of Dexcom.1 “Almost one year later we are thrilled to report that Dexcom G7 is already available in eight countries, Dexcom ONE has played a significant role in helping expand CGM coverage for millions more people with diabetes and Dexcom G6 continues to lead the industry in connectivity with automated insulin delivery systems and digital health apps.”
Check out this special edition ATTD 23 episode of Diabetes Dialogue with Leach, where he discusses the global rollout of the Dexcom G7, Dexcom’s future research plans, and the company’s access initiatives.
In addition to sponsored symposiums and industry presentations, the ATTD 23 meeting also saw a multitude of oral and poster presentations related to use of Dexcom technology in different patient groups and various settings.
Although a multitude of studies have provided a comprehensive overview of the effects of real-time continuous glucose monitoring in patients with type 2 diabetes, a team led by Thomas Grace, MD, medical director of the Blanchard Valley Diabetes Center, sought to investigate the potential benefit of this technology in an often-overlooked patient population: the uninsured. With this in mind, investigators designed their study with the intent of providing Dexcom G6 systems to a cohort of 200 patients to estimate the effects of initiation on glucose control in this patient population. Of note, Grace’s ATTD 2023 presentation contained interim data from a cohort of 31 patients with at least 2 HbA1c values available for analysis.
This cohort had a mean BMI of 37.8 kg/m2 and all patients had a baseline HbA1c value of 7.4% or greater. Grace pointed out all study participants were considered CGM-naive and there were no restrictions for study entry based on comorbidities or diabetes treatment regimens. Per trial protocol, no formal training was provided to patients or prescribers.
Upon analysis, results indicated the cohort’s mean HbA1c was reduced from 9.9% (SD, 1.9) at baseline to 7.2% (SD, 1.1) at 3 months and further reduced to 7.1% (SD, 1.3) at 6 months. This trend was consistent, regardless of whether or not patients reported insulin use at baseline. Results also indicated no device-related adverse events were reported among participants.
“It is likely that people used the data to modify dietary and behavioral choices. The large and clinically significant HbA1c reductions will likely reduce the risk of long-term complications. Expanded coverage for RT-CGM devices may have beneficial cost implications for insurance providers,” wrote investigators.2
Led by Erin Cobry, MD, and fellow investigators from the Barbara Davis Center for Diabetes at the University of Colorado, the current study, which was a retrospective chart review, was launched with the intent of assessing the utility of the Dexcom G6 in in-hospital settings among people with type 1 diabetes. Limiting their study to pediatric patients 17 years or younger with type 1 diabetes, investigators obtained data related to 497 paired glucose values from a cohort of 32 patients.
This cohort had a median age of 14.5 years, 59.4% were female, and 68.8% were non-Hispanic White. From hospital records investigators obtained data related to blood glucose values, diagnostic codes, and medication administration while hospitalized. For the purpose of analysis, the primary outcome of interest for the investigators’ analyses was the mean absolute relative difference (MARD). Upon analysis, results indicated the overall MARD was 12.5%, the medical floor MARD was 11.6%, and the intensive care unit MARD was 15.5%. Investigators pointed out 97.6% were within the A&B zones in each group.
“It is important to be able to apply this technology to the inpatient setting where close glucose monitoring is especially important. Future prospective studies and impatient protocols will be important to ensure safe and feasible use of continuous glucose monitors in both the pediatric and adult hospital settings,” Cobry said.3
Led by Othmar Moser, PhD, of the University of Bayreuth in Germany, and a team of investigators representing institutions in Germany and Austria, the current study was a secondary outcome analysis of the performance assessment of the Dexcom G6 around exercise in different glycemic ranges from within the ULTRAFLEXI-1 study. A randomized crossover trial comparing insulin glargine 300 u/mL and insulin degludec 100 U/mL around spontaneous exercise sessions in adults with type 1 diabetes, the study provided investigators with data for assessing real-time continuous glucose monitoring performance during exercise from 25 people with type 1 diabetes.
The study cohort had a mean age of 41.4 (SD, 11.9) years, mean HbA1c of 7.5% (SD, 0.8), and 56% were male. From this cohort investigators were provided with data from 24 moderate-intensity cycle-ergometer lab exercise sessions, with a duration of 60 minutes each. As part of the ULTRAFLEXI-1 study, reference blood glucose was compared against sensor glucose levels every 6 minutes. For the purpose of analysis, sensor accuracy was assessed by means of median absolute relative difference (MARD). Analysis of pre-exercise resting conditions, where 98.8% of sensor readings were available, achieved a MARD of 9.4% (Interquartile range [IQR], 4.5-17.7).
Analysis of readings during exercise, which included 98.9% of sensor readings, suggested an achieved MARD of 14.4% (IQR, 7.1-23.6). Further analysis of exercise and reference glucose levels indicated the MARD for time below 70 mg/dL was 39.6% (IQR, 31.5-47.2), for time in range of 70-180 mg/dL the MARD was 15.4% (IQR, 7.9-24.6) and for time above 180 mg/dL the MARD was 9.6% (IQR, 4.7-15.9).
“This secondary outcome analysis showed high accuracy during resting conditions for the Dexcom G6 system that deteriorated during exercise. During hypoglycemia and exercise sensor glucose readings overestimated blood glucose levels,” wrote investigators.4