Examining a Remote Group-Based Type 2 Diabetes Self-Management Education Program in the COVID-19 Era Using the ORBIT Model: Small 6-Week Feasibility Study

BACKGROUND

To date, most group-based diabetes self-management education (DSME) programs for type 2 diabetes (T2D) have been delivered in person. The rapid transition to remote care at the outset of the COVID-19 pandemic presented opportunities to test, evaluate, and iterate a new remote DSME program.

OBJECTIVE

We aim to refine the delivery and evaluation of a multicomponent remote DSME program for adults living with T2D by examining several feasibility outcomes.

METHODS

We recruited a convenience sample of patients from a London, Canada, outpatient diabetes clinic (serving high-risk, low-income adults) to participate in a 6-week, single cohort feasibility study from November 2020 to March 2021. This small ORBIT phase 1b feasibility study represents the first in a planned series guided by the ORBIT model for developing behavioral interventions for chronic diseases (phase 1: design; phase 2: preliminary testing; phase 3: efficacy; and phase 4: effectiveness). The feasibility of delivering and evaluating a remote DSME program, including (1) live video education classes, (2) individualized physical activity (PA) prescription and counseling, and (3) intermittently scanned continuous glucose and wearable PA monitoring, was assessed. Feasibility outcomes included recruitment and retention rates, program adherence, and acceptability (ie, technology issues and exit survey feedback). PA was assessed with Fitbit Inspire 2 (Fitbit Inc) and estimated glycated hemoglobin (HbA1c) using the FreeStyle Libre (Abbot). Given the small study sample, group- and individual-level data are reported descriptively.

RESULTS

A total of 10 adults living with T2D were recruited (female 60%; age 49.9, SD 14.3 years; estimated HbA1c 6.2%, SD 0.5%). Recruitment and retention rates were 29% and 80%, respectively. Participants attended 83% (25/30) and 93% (37/40) of education classes and PA counseling phone calls, respectively. There were 3.2 (SD 2.6) technology issues reported per person, most of which were related to study data transfer. Exit survey responses suggest most participants (8/9, 89%) were "satisfied" with the program. Recognizing the small sample size and the fact that no inferential statistics were conducted, the mean (SD) for the weekly daily step count and estimated HbA1c are provided for illustrative purposes. Participants accumulated 7103 (SD 2900) and 7515 (SD 3169) steps per day at baseline and week 6, respectively. The estimated HbA1c was 6.2% (SD 0.5%) and 6.2% (SD 0.6%) at baseline and week 6, respectively.

CONCLUSIONS

This ORBIT phase 1b study served to refine the delivery (eg, automatic study data upload process recommended to reduce participant burden) and evaluation (eg, purposeful sampling of participants with baseline HbA1c >8% recommended to address selection bias) of a remote DSME program. Preliminary proof-of-concept testing (ORBIT phase 2) incorporating some of these learnings is now warranted.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04498819; https://clinicaltrials.gov/study/NCT04498819.

Real-world glycaemic outcomes in patients with type 1 diabetes using glucose sensors-Experience from a single centre in Dublin

AIMS

To evaluate changes in glycated haemoglobin (HbA1 c) and sensor-based glycaemic metrics after glucose sensor commencement in adults with T1D.

METHODS

We performed a retrospective observational single-centre study on HbA1 c, and sensor-based glycaemic data following the initiation of continuous glucose monitoring (CGM) in adults with T1D (n = 209).

RESULTS

We observed an overall improvement in HbA1 c from 66 (59-78) mmol/mol [8.2 (7.5-9.3)%] pre-sensor to 60 (53-71) mmol/mol [7.6 (7.0-8.6)%] on-sensor (p < .001). The pre-sensor HbA1 c improved from 66 (57-74) mmol/mol [8.2 (7.4-8.9)%] to 62 (54-71) mmol/mol [7.8 (7.1-8.7)%] within the first year of usage to 60 (53-69) mmol/mol [7.6 (7.0-8.4)%] in the following year (n = 121, p < .001). RT-CGM-user had a significant improvement in HbA1 c (Dexcom G6; p < .001, r = 0.33 and Guardian 3; p < .001, r = 0.59) while a non-significant reduction was seen in FGM-user (Libre 1; p = .279). Both MDI (p < .001, r = 0.33) and CSII group (p < .001, r = 0.41) also demonstrated significant HbA1 c improvement. Patients with pre-sensor HbA1 c of ≥64 mmol/mol [8.0%] (n = 125), had attenuation of pre-sensor HbA1 c from 75 (68-83) mmol/mol [9.0 (8.4-9.7)%] to 67 (59-75) mmol/mol [8.2 (7.6-9.0)%] (p < .001, r = 0.44). Altogether, 25.8% of patients achieved the recommended HbA1 c goal of ≤53 mmol/mol and 16.7% attained the recommended ≥70% time in range (3.9-10.0 mmol/L).

CONCLUSIONS

Our study demonstrated that minimally invasive glucose sensor technology in adults with T1D is associated with improvement in glycaemic outcomes. However, despite significant improvements in HbA1 c, achieving the recommended goals for all glycaemic metrics remained challenging.

Assessment of the FreeStyle Libre 2 interstitial glucose monitor in hypo- and euglycemic cats

BACKGROUND

Continuous glucose monitoring systems have been validated for eu- and hyperglycemic cats. The FreeStyle Libre 2 (FSL2) is sufficiently accurate in people during hypoglycemia to guide critical treatment decisions without confirmation of blood glucose concentration (BG).

OBJECTIVES

Assess FSL2 accuracy in cats with hypoglycemia.

ANIMALS

Nine healthy, purpose-bred cats.

METHODS

Hyperinsulinemic-hypoglycemic clamps were performed by IV infusion of regular insulin (constant rate) and glucose (variable rate). Interstitial glucose concentration (IG), measured by FSL2, was compared to BG measured by AlphaTrak2. Data were analyzed for all paired measurements (n = 364) and separately during stable BG (≤1 mg/dL/min change over 10 minutes). Pearson's r test, Bland-Altman test, and Parkes Error Grid analysis respectively were used to determine correlation, bias, and clinical accuracy (P < .05 considered significant).

RESULTS

Overall, BG and IG correlated strongly (r = 0.83, P < .0001) in stable glycemia and moderately at all rates of change (r = 0.69, P < .0001). Interstitial glucose concentration underestimated BG in euglycemia, but the BG-IG difference was progressively smaller as BG decreased (12.9 ± 12.2, 8.8 ± 11.2, -3.2 ± 7.4, and -7.8 ± 5.2 mg/dL in the ranges of 80-120 [n = 64], 60-79 [n = 29], 50-59 [n = 71], and 29-49 mg/dL [n = 53], respectively).

CONCLUSIONS

Although IG underestimates BG throughout most of the hypo-euglycemic range, IG generally overestimates BG in marked hypoglycemia (<60 mg/dL). It is therefore imperative to evaluate FSL2 results in this critical range with caution.

Performance of the FreeStyle Libre Flash Glucose Monitoring System during an Oral Glucose Tolerance Test and Exercise in Healthy Adolescents

This study's aim was to assess FreeStyle Libre Flash glucose monitoring (FGM) performance during an oral glucose tolerance test (OGTT) and treadmill exercise in healthy adolescents. This should advance the feasibility and utility of user-friendly technologies for metabolic assessments in adolescents. Seventeen healthy adolescents (nine girls aged 12.8 ± 0.9 years) performed an OGTT and submaximal and maximal treadmill exercise tests in a laboratory setting. The scanned interstitial fluid glucose concentration ([ISFG]) obtained by FGM was compared against finger-prick capillary plasma glucose concentration ([CPG]) at 0 (pre-OGTT), -15, -30, -60, -120 min post-OGTT, pre-, mid-, post- submaximal exercise, and pre- and post- maximal exercise. Overall mean absolute relative difference (MARD) was 13.1 ± 8.5%, and 68% (n = 113) of the paired glucose data met the ISO 15197:2013 criteria. For clinical accuracy, 84% and 16% of FGM readings were within zones A and B in the Consensus Error Grid (CEG), respectively, which met the ISO 15197:2013 criteria of having at least 99% of results within these zones. Scanned [ISFG] were statistically lower than [CPG] at 15 (-1.16 mmol∙L^-1, p < 0.001) and 30 min (-0.74 mmol∙L^-1, p = 0.041) post-OGTT. Yet, post-OGTT glycaemic responses assessed by total and incremental areas under the curve (AUCs) were not significantly different, with trivial to small effect sizes (p ≥ 0.084, d = 0.14-0.45). Further, [ISFGs] were not different from [CPGs] during submaximal and maximal exercise tests (interaction p ≥ 0.614). FGM can be a feasible alternative to reflect postprandial glycaemia (AUCs) in healthy adolescents who may not endure repeated finger pricks.

Validity of Danish public criteria for providing flash glucose monitoring to participants with type 1 diabetes-An explorative cohort study

INTRODUCTION

Flash glucose monitor (FGM) use is increasing. A set of Danish criteria for regulating the use has been released. We assessed their validity.

METHODS

Patients with type 1 diabetes attending our clinic were offered Freestyle Libre Sensor for 12 months and stratified into fulfilling the Danish regional criteria (RC+) or not (RC-). Primary endpoint was achieving individualized target HbA1c. Secondary endpoints were HbA1c reduction ≥5%, time in range (TIR), time below range (TBR), daily scans, change in median HbA1c, and noted experiences.

RESULTS

Two hundred seventy-eight participants were included. Forty-four participants met target HbA1c after 1 year. No difference between RC+ and RC- was observed (p = .136). Higher age was associated with probability to meet target HbA1c (RR = 3.15, [95% CI: 1.15, 8.62]) as was frequent scans (RR = 1.88, [95% CI: 0.99, 3.57]). One hundred twenty-three participants met an HbA1c reduction ≥5%, the majority represented in RC+ (p = .023). Higher baseline HbA1c was associated with a reduction of HbA1c ≥5% after 1 year (RR = 1.97, [95% CI: 1.40, 2.78]). There was no difference between RC+ and RC- in TIR, TBR, and daily scans. Positive experiences dominated from both participants and healthcare professionals. More positive experiences were noted from healthcare professionals in RC- (p = .003) but no difference in reported experiences among participants in RC+ and RC- (p = .880).

CONCLUSION

The Danish Regional Criteria seems not a valid tool for regulation of FGM. Participants of older age and participants with more frequent daily scans might benefit more from FGM.

Association between Flash Glucose Monitors and A1C: A Retrospective Pre-Post Analysis

Background: Randomized controlled trials have investigated the effect of continuous glucose monitors on hemoglobin A1C; however, more evidence is needed to justify their use and expand insurance coverage. Additionally, there are few published studies investigating the A1C lowering effect of flash glucose monitors (FGMs) in broad diabetes populations with varying insulin requirements. This analysis aimed to help fill this gap in medical literature and help clinicians evaluate costs/benefits when considering FGMs for their patients with diabetes. Objectives: To determine the association between FGM use and A1C reduction in patients with type 1 or type 2 diabetes mellitus regardless of insulin dependence. Methods: Pharmacy dispensing records were used to identify patients for inclusion. Patients who received a FGM from a University of Utah pharmacy between July 7, 2018 and July 7, 2020 were included. Patients who did not receive at least an 84-day supply of FGM sensors or did not have a baseline or follow-up A1C were excluded. Baseline and follow-up A1Cs, defined as A1Cs that are within one year before and 3-12 months after the FGM dispense date, were collected for each patient. New diabetes medications within a six-month window of the initial FGM dispense date were also recorded. Outcome variables were collected before and after patients received their first FGM (pre-FGM vs. post-FGM, respectively). The primary outcome was the difference between baseline and follow-up A1C for each patient. Secondary outcomes were the difference in baseline and follow-up A1C for various clinical subgroups within the overall sample. Descriptive statistics were used to summarize baseline characteristics and outcome data. Paired Student's t-tests were used to evaluate outcome differences (α=0.05). Results: Fifty-seven patients (50.8% male; mean age: 49 years) were included. For the primary outcome, the average baseline and follow-up A1Cs were 9.33% and 8.32%, respectively for a difference of -1.01% ([95%CI -1.31:-0.72]; p<0.0001). Conclusions: The use of FGMs is associated with decreases in A1C within a cohort of patients at one health system. Further effort to determine impact of FGM on clinical and economic outcomes is warranted.

Differences Between Flash Glucose Monitor and Fingerprick Measurements

Freestyle Libre (FL) is a factory calibrated Flash Glucose Monitor (FGM). We investigated Mean Absolute Relative Difference (MARD) between Self Monitoring of Blood Glucose (SMBG) and FL measurements in the first day of sensor wear in 39 subjects with Type 1 diabetes. The overall MARD was 12.3%, while the individual MARDs ranged from 4% to 25%. Five participants had a MARD ≥ 20%. We estimated bias and lag between the FL and SMBG measurements. The estimated biases range from -1.8 mmol / L to 1.4 mmol / L , and lags range from 2 min to 24 min . Bias is identified as a main cause of poor individual MARDs. The biases seem to persist in days 2⁻7 of sensor usage. All cases of MARD ≥ 20% in the first day are eliminated by bias correction, and overall MARD is reduced from 12.3% to 9.2%, indicating that adding support for voluntary user-supplied bias correction in the FL could improve its performance.