Accuracy of a Factory-Calibrated Continuous Glucose Monitor in Individuals With Diabetes on Hemodialysis

OBJECTIVE

Continuous glucose monitoring (CGM) improves diabetes management, but its reliability in individuals on hemodialysis is poorly understood and potentially affected by interstitial and intravascular volume variations.

RESEARCH DESIGN AND METHODS

We assessed the accuracy of a factory-calibrated CGM by using venous blood glucose measurements (vBGM) during hemodialysis sessions and self-monitoring blood glucose (SMBG) at home.

RESULTS

Twenty participants completed the protocol. The mean absolute relative difference of the CGM was 13.8% and 14.4%, when calculated on SMBG (n = 684) and on vBGM (n = 624), and 98.7% and 100% of values in the Parkes error grid A/B zones, respectively. Throughout 181 days of CGM monitoring, the median time in range (70-180 mg/dL) was 38.5% (interquartile range 29.3-57.9), with 28.7% (7.8-40.6) of the time >250 mg/dL.

CONCLUSIONS

The overall performance of a factory-calibrated CGM appears reasonably accurate and clinically relevant for use in practice by individuals on hemodialysis and health professionals to improve diabetes management.

Clinical Evaluation of a Novel CGM-Informed Bolus Calculator with Automatic Glucose Trend Adjustment

Background: Expert opinion guidelines and limited data from clinical trials recommend adjustment to bolus insulin doses based on continuous glucose monitor (CGM) trend data, yet minimal evidence exists to support this approach. We performed a clinical evaluation of a novel CGM-informed bolus calculator (CIBC) with automatic insulin bolus dose adjustment based on CGM trend used with sensor-augmented pump therapy. Materials and Methods: In this multicenter, outpatient study, participants 6-70 years of age with type 1 diabetes (T1D) used the Omnipod^® 5 System in Manual Mode, first for 7 days without a connected CGM (standard bolus calculator, SBC, phase 1) and then for 7 days with a connected CGM using the CIBC (CIBC phase 2). The integrated bolus calculator used stored pump settings plus user-estimated meal size and/or either a manually entered capillary glucose value (SBC phase) or an imported current CGM value and trend (CIBC phase) to recommend a bolus amount. The CIBC automatically increased or decreased the suggested bolus amount based on the CGM trend. Results: Twenty-five participants, (mean ± standard deviation) 27 ± 15 years of age, with T1D duration 12 ± 9 years and A1C 7.0% ± 0.9% completed the study. There were significantly fewer sensor readings <70 mg/dL 4 h postbolus with the CIBC compared to the SBC (2.1% ± 2.0% vs. 2.8 ± 2.7, P = 0.03), while percent of sensor readings >180 and 70-180 mg/dL remained the same. There was no difference in insulin use or number of boluses given between the two phases. Conclusion: The CIBC was safe when used with the Omnipod 5 System in Manual Mode, with fewer hypoglycemic readings in the postbolus period compared to the SBC. This trial was registered at ClinicalTrials.gov (NCT04320069).

First Outpatient Evaluation of a Tubeless Automated Insulin Delivery System with Customizable Glucose Targets in Children and Adults with Type 1 Diabetes

Background: The objective of this study was to assess the safety and effectiveness of the first commercial configuration of a tubeless automated insulin delivery system, Omnipod^® 5, in children (6-13.9 years) and adults (14-70 years) with type 1 diabetes (T1D) in an outpatient setting. Materials and Methods: This was a single-arm, multicenter, prospective clinical study. Data were collected over a 14-day standard therapy (ST) phase followed by a 14-day hybrid closed-loop (HCL) phase, where participants (n = 36) spent 72 h at each of three prespecified glucose targets (130, 140, and 150 mg/dL, 9 days total) then 5 days with free choice of glucose targets (110-150 mg/dL) using the Omnipod 5. Remote safety monitoring alerts were enabled during the HCL phase. Primary endpoints were difference in time in range (TIR) (70-180 mg/dL) between ST and HCL phases and proportion of participants reporting serious device-related adverse events. Results: Mean TIR was significantly higher among children in the free-choice period overall (64.9% ± 12.2%, P < 0.01) and when using a 110 mg/dL target (71.2% ± 10.2%, P < 0.01), a 130 mg/dL target (61.5% ± 7.7%, P < 0.01), and a 140 mg/dL target (64.8% ± 11.6%, P < 0.01), and among adults using a 130 mg/dL target (75.1% ± 11.6%, P < 0.05), compared to the ST phase (children: 51.0% ± 13.3% and adults: 65.6% ± 15.7%). There were no serious device-related adverse events reported during the HCL phase, nor were there episodes of severe hypoglycemia or diabetic ketoacidosis. Conclusion: The Omnipod 5 System was safe and effective when used at glucose targets from 110 to 150 mg/dL for 14 days at home in children and adults with T1D.

Using technology to advance type 1 diabetes care among women during the reproductive years and in pregnancy

The prevalence of diabetes is increasing globally. Technology to improve care among individuals with diabetes is constantly being developed. Women living with Type 1 Diabetes Mellitus (T1DM) have unique challenges affecting their glucose control relating to menstrual cycles, pregnancy, and menopause. The purpose of this review is to examine the literature related to the use of technology to help women with T1DM manage their diabetes during the reproductive years, pregnancy, and beyond. Continuous subcutaneous insulin infusion (CSII) therapy can provider equivalent or better glucose control when compared with multiple daily injections (MDI), with less hypoglycemia, diabetic ketoacidosis, and weight gain. The CSII therapy has features that could help improve glucose control over the menstrual cycle, menopause, and pregnancy, although the most studied of these stages is pregnancy. Continuous glucose monitoring (CGM) can be combined with any insulin delivery system (MDI or CSII) to provide data on glucose values every few minutes and show glucose trends over time. CGM introduction can highlight glucose variability for women with T1DM, may be beneficial during pregnancy, and can reduce hypoglycemia. Sensor-augmented pump therapy and hybrid artificial pancreas (closed-loop) systems are promising tools that improve outcomes among individuals with diabetes. The use of modern technology to improve glucose and metabolic control among menopausal women with diabetes has not been well studied. Internet and phone-based technologies are emerging as important tools that may help with diabetes self-care for women living with diabetes.

Use of continuous glucose monitoring in subjects with type 1 diabetes on multiple daily injections versus continuous subcutaneous insulin infusion therapy: a prospective 6-month study

OBJECTIVE

To compare use of continuous glucose monitoring in subjects with type 1 diabetes on multiple daily injection (MDI) therapy versus continuous subcutaneous insulin infusion (CSII) therapy for 6 months.

RESEARCH DESIGN AND METHODS

Sixty type 1 diabetic adults with similar baseline characteristics, using either MDI (n = 30) or CSII (n = 30) therapy, were enrolled in this 6-month prospective study. Subjects were instructed to wear the DexCom SevenPLUS continuous glucose monitor at all times throughout the study. All subjects were initially blinded from the continuous glucose monitoring (CGM) glucose data. After 4 weeks of blinded CGM use, the CGM was unblinded, making glucose data available to the patient. The CGM remained in the unblinded state for the remainder of the study (20 weeks). Clinic visits occurred every 4 weeks, at which time A1C values were collected and CGM data were downloaded.

RESULTS

Mean baseline (± SD) A1C was 7.61 (± 0.76) and 7.63 (± 0.68) for CSII and MDI, respectively (P > 0.05). Without any significant therapy change, A1C decrease at 12 weeks was similar in both groups (P = 0.03). When compared with the blinded phase, unblinded use of CGM was associated with similar but significant reductions in glycemic control and variability parameters. In addition, both therapy groups had similar changes in mean glucose and glucose variability indexes at 3 and 6 months (ITT analysis, P > 0.05). Predefined per protocol analysis (sensor use at least 6 days/week) showed greater improvement in time spent in target range glycemia, 3.9-10.0 mmol/L (70-180 mg/dL), in the CSII group.

CONCLUSIONS

We conclude that CGM provides similar benefits in glucose control for patients using MDI or CSII therapy.

Feasibility of 10-day use of a continuous glucose-monitoring system in adults with type 1 diabetes

OBJECTIVE

The purpose of this pilot study was to evaluate the feasibility of 10-day use of a transcutaneous, real-time, continuous glucose-monitoring (CGM) system. All previous reports using different CGM systems were for 3-, 5-, or 7-day use.

RESEARCH DESIGN AND METHODS

On day 1, subjects received the CGM device (SEVEN System) and underwent training on proper use. Subjects returned to the clinic on days 2, 7, and 10 for in-clinic sessions. On days 2 and 7, half the subjects performed fingersticks every 15 min and the other half had Yellow Springs Instruments (YSI) samples drawn every 15 min. On day 10, all subjects participated in an 8-h in-clinic session with YSI and fingerstick testing.

RESULTS

The median absolute relative difference for CGM versus YSI was 12.6, 11.3, and 14.5% on days 2, 7, and 10, respectively (P = 0.63). CGM performed better on day 10 when compared with self-monitoring of blood glucose as compared with YSI.

CONCLUSIONS

This is the first study to document 10-day use of a 7-day CGM system.