IMpact of flash glucose Monitoring in pEople with type 2 Diabetes Inadequately controlled with non-insulin Antihyperglycaemic ThErapy (IMMEDIATE): A randomized controlled trial

AIM

To examine the efficacy and patient satisfaction of intermittently scanned continuous glucose monitoring (isCGM) in adults using non-insulin therapies for the management of type 2 diabetes.

MATERIALS AND METHODS

The IMMEDIATE study was a multisite, open label, randomized controlled trial with follow-up at 16 weeks. Adults with type 2 diabetes using at least one non-insulin therapy, with an HbA1c of 7.5% or higher (≥ 58 mmol/mol), were randomized 1:1 to receive an isCGM device plus diabetes self-management education (isCGM + DSME) or DSME alone. Enrolment occurred from 8 September 2020 to 24 December 2021. The primary outcome was percentage mean time in range (TIR), in the final 2-week period, measured via blinded CGM.

RESULTS

One hundred and sixteen participants were randomized (mean age, 58 years; diabetes duration, 10 years; mean HbA1c, 8.6% [70 mmol/mol]). At 16 weeks of follow-up, the isCGM and DSME arm had a significantly greater mean TIR by 9.9% (2.4 hours) (95% CI, -17.3% to -2.5%; P < .01), significantly less time above range by 8.1% (1.9 hours) (95% CI, 0.5% to 15.7%; P = .037), and a greater reduction in mean HbA1c by 0.3% (3 mmol/mol) (95% CI, 0% to 0.7%; P = .048) versus the DSME arm. Time below range was low and not significantly different between groups and hypoglycaemic events were few in both groups. Glucose monitoring satisfaction was higher among isCGM users (adjusted difference -0.5 [95% CI, -0.7 to -0.3], P < .01).

CONCLUSIONS

The IMMEDIATE study has shown that among non-insulin-treated individuals with type 2 diabetes, use of isCGM is associated with an improvement in glycaemic outcomes.

Real-world glycaemic outcomes in adult persons with type 1 diabetes using a real-time continuous glucose monitor compared to an intermittently scanned glucose monitor: A retrospective observational study from the Canadian LMC diabetes registry (REAL-CGM-T1D)

Real-time continuous glucose monitoring (rtCGM) and intermittently scanned CGM (isCGM) have both been shown to improve glycaemic outcomes in people with T1D. The aim of this study was to compare real-world glycaemic outcomes at 6-12 months in a propensity score matched cohort of CGM naïve adults with T1D who initiated a rtCGM or an isCGM. Among the matched rtCGM and isCGM cohorts (n = 143/cohort), rtCGM users had a significantly greater HbA_1c benefit compared to isCGM users (adjusted difference, -3 mmol/mol [95% CI, -5 to -1]; -0.3% [95% CI, -0.5 to -0.1]; p = 0.01). There was a significantly greater lowering of HbA_1c for rtCGM compared to isCGM when baseline HbA_1c was <69 mmol/mol (8.5%) (adjusted difference, -4 mmol/mol [95% CI, -7 mmol/mol to -2 mmol/mol]; -0.4% [95% CI, -0.6% to -0.2%]; p < 0.001), and in MDI users (adjusted difference, -3 mmol/mol [95% CI, -6 mmol/mol to -0 mmol/mol]; -0.3% [95% CI -0.5% to 0.0%], p = 0.04). The rtCGM cohort had significantly greater time in range (58.3 ± 16.1% vs. 54.5 ± 17.1%, p = 0.03), lower time below range (2.1 ± 2.7% vs. 6.1 ± 5.0%, p < 0.001) and lower glycaemic variability compared to the isCGM cohort. In this real-world analysis of adults with T1D, rtCGM users had a significantly greater reduction in HbA_1c at 6-12 months compared to isCGM, and significantly greater time in range, lower time below range and lower glycaemic variability, compared to a matched cohort of isCGM users.

The Canadian LMC Diabetes Registry: A Profile of the Demographics, Management, and Outcomes of Individuals with Type 1 Diabetes

Objective: Clinical guidelines now define the standard of diabetes care, but few health care jurisdictions systematically assess their practicality and impact. The Canadian LMC Diabetes Registry includes the electronic health records of >50 endocrinologists in three provinces and provides quarterly real-time outcome reports to each endocrinologist. This retrospective cohort study aimed to characterize the demographics, treatment regimens, and outcomes of the type 1 diabetes (T1D) patient population in the registry. Research Design and Methods: Adults were included if they had a clinical diagnosis of T1D, had seen an LMC endocrinologist between July 1, 2015 and June 30, 2018, and had follow-up >6 months. This study is registered on clinicaltrials.gov (NCT04162067). Results: The resulting cohort included 3600 individuals with mean age of 43.9 ± 15.3 years and duration of diabetes of 21.5 ± 13.9 years. Mean hemoglobin A1C (HbA1c) was 8.1% ± 1.5% and only 22.5% had achieved HbA1c ≤7.0%. In each measure, individuals in younger cohorts showed poorer glycemic control than older cohorts. Within each age cohort, insulin pump users showed a lower mean HbA1c than those using multiple daily injections, especially in cohorts who were also not using a continuous glucose monitor. Overall, 63.1% reported at least weekly hypoglycemia, whereas 3.6% reported severe hypoglycemia ≥1 per year. Conclusions: Despite receiving care in an advanced well-resourced environment, within a public health care system, from specialists armed with regular patient outcomes feedback, most individuals with T1D are unable to achieve the goals recommended by clinical practice guidelines.

Semaglutide once weekly in people with type 2 diabetes: Real-world analysis of the Canadian LMC diabetes registry (SPARE study)

AIMS

To investigate real-world short-term clinical outcomes in adults with type 2 diabetes (T2D) who initiated semaglutide in a specialist endocrinology practice in Canada.

MATERIALS AND METHODS

This study was a retrospective observational study using data from the Canadian LMC Diabetes Registry. Adults with T2D who were naïve to glucagon-like peptide-1 receptor agonist (GLP-1RA) therapy, initiated semaglutide therapy as usual standard of care between February 2018 and February 2019, and maintained semaglutide therapy during follow-up, were eligible for analysis. The primary outcome was mean change in glycated haemoglobin (HbA1c) at 3- to 6-month follow-up.

RESULTS

In the final analytical cohort (n = 937), there was a statistically significant mean ± SD reduction in HbA1c of -1.03 ± 1.24% (11.3 ± 13.6 mmol/mol, P < 0.001) and weight of -3.9 ± 4.0 kg (P < 0.001), with no significant change in self-reported incidence of hypoglycaemia. There was a significant reduction in HbA1c and weight regardless of number of co-therapies or semaglutide dose. However, adults using the 1.0-mg dose had a significantly greater reduction in HbA1c compared to adults using the 0.25- to 0.5-mg dose (between-group difference - 0.24 ± 0.06%, 2.6 ± 0.7 mmol/mol; P < 0.001). Adults using basal-bolus therapy required a significantly lower median total daily dose of insulin after adding semaglutide (0.82 vs. 0.93 U/kg; P < 0.001).

CONCLUSIONS

This retrospective observational study demonstrated that GLP-1RA-naïve adults with T2D initiating semaglutide in a real-world clinical practice had a statistically and clinically significant reduction in HbA1c and body weight after 3 to 6 months, regardless of semaglutide dose or order of semaglutide therapy, with no significant change in reported incidence of hypoglycaemia.

Goal achievement of HbA1c and LDL-cholesterol in a randomized trial comparing colesevelam with ezetimibe: GOAL-RCT

AIM

To compare the efficacy and safety of colesevelam and ezetimibe as second-line low density lipoprotein-cholesterol (LDL-c)-lowering options in type 2 diabetes (T2D).

MATERIALS AND METHODS

GOAL-RCT is a 24-week, open-label, randomized, pragmatic clinical trial. Subjects with T2D with uncontrolled HbA1c (7.1%-10%) and LDL-c (>2.0 mmol/L) were randomized 1:1 to colesevelam 3.75 g or ezetimibe 10 mg daily. The primary composite outcome was the proportion of participants achieving an LDL-c target of ≤2.0 mmol/L and HbA1c target of ≤7.0%. Intention to treat analysis was performed.

RESULTS

Two hundred subjects were enrolled: mean age 59 ± 10 years; mean HbA1c 8.0%; mean LDL-c 2.5 mmol/L; 97% on statin therapy. The primary composite outcome was achieved by similar proportions of participants with colesevelam (14.6%) and ezetimibe (10.5%) (P_{non-inferiority}  < .001, P_superiority = .41). LDL-c reduction from baseline was less with colesevelam compared with ezetimibe (14.0% vs. 23.2%, P < .01), as was the proportion of subjects achieving an LDL-c target of ≤2.0 mmol/L (47.6% and 67.0%, respectively; P = .007). Mean HbA1c was reduced with colesevelam (-0.26 ± 0.10%), while no change was observed with ezetimibe (difference P = .06). Adverse events and discontinuation rates were higher for colesevelam (20.2% and 31.1%) compared with ezetimibe (7.2% and 6.2%), respectively.

CONCLUSIONS

Among subjects with T2D, the initiation of colesevelam or ezetimibe led to similar achievement of primary composite outcome (LDL-c and HbA1c within target), with ezetimibe recording a greater LDL-c reduction and better tolerability than colesevelam.

Intact olfactory memory in the 5xFAD mouse model of Alzheimer's disease from 3 to 15 months of age

Alzheimer's disease (AD) is an age-related neurodegenerative disorder that causes profound cognitive dysfunction. Deficits in olfactory memory occur in early stages of AD and may be useful in AD diagnosis. The 5xFAD mouse is a commonly used model of AD, as it develops neuropathology, cognitive and sensori-motor dysfunctions similar to those seen in AD. However, olfactory memory dysfunction has not been studied adequately or in detail in 5xFAD mice. Furthermore, despite sex differences in AD prevalence and symptom presentation, few studies using 5xFAD mice have examined sex differences in learning and memory. Therefore, we tested olfactory memory in male and female 5xFAD mice from 3 to 15 months of age using a conditioned odour preference task. Olfactory memory was not impaired in male or female 5xFAD mice at any age tested, nor were there any sex differences. Because early-onset impairments in very long-term (remote) memory have been reported in 5xFAD mice, we trained a group of mice at 3 months of age and tested olfactory memory 90 days later. Very long-term olfactory memory in 5xFAD mice was not impaired, nor was their ability to perform the discrimination task with new odourants. Examination of brains from 5xFAD mice confirmed extensive Aβ-plaque deposition spanning the olfactory memory system, including the olfactory bulb, hippocampus, amygdala and piriform cortex. Overall this study indicates that male and female 5xFAD mice do not develop olfactory memory deficits, despite extensive Aβ deposition within the olfactory-memory regions of the brain.

Flexible insulin therapy with a hybrid regimen of insulin degludec and continuous subcutaneous insulin infusion with pump suspension before exercise in physically active adults with type 1 diabetes (FIT Untethered): a single-centre, open-label, proof-of-concept, randomised crossover trial

BACKGROUND

People with type 1 diabetes who use continuous subcutaneous insulin infusion (CSII, or insulin pump therapy) often remove their pump before extended periods of exercise, but this approach might result in reduced glycaemic control and increased risk of hyperglycaemia and ketogenesis. We aimed to assess the efficacy and safety of a hybrid approach, in which basal insulin delivery was divided between CSII and a daily injection of insulin degludec.

METHODS

In this single-centre, open-label, proof-of-concept, randomised crossover trial done at the LMC Diabetes & Endocrinology research centre, we recruited physically active and aerobically fit participants aged 18 years or older with type 1 diabetes who were using CSII. Participants were randomly assigned (1:1) by use of a computer-generated sequence to one of two sequences of either usual CSII, involving the continuation of the participant's usual CSII regimen, followed by crossover to hybrid CSII, in which the delivery of the participant's usual daily basal insulin dose was split (50% delivered by CSII and 50% delivered by a once-daily morning injection of 100 U/mL insulin degludec), or the opposite sequence (ie, hybrid CSII followed by crossover to usual CSII). Treatment was not masked to the investigators or participants. For each intervention, participants completed a moderate-intensity and a high-intensity in-clinic exercise session in the first week, followed by four high-intensity and two moderate-intensity home-based exercise sessions in the subsequent 3 weeks. Insulin pumps were suspended or disconnected 60 min before exercise and reconnected immediately after exercise during both treatment regimens. The coprimary outcomes were: (1) time spent in the target control range of 4·0-10·0 mmol/L blood glucose after high-intensity exercise, and (2) time spent in target control range of 4·0-10·0 mmol/L blood glucose after moderate-intensity exercise, measured by continuous glucose monitoring in the 6-h period from the start of the high-intensity and moderate-intensity in-clinic exercise sessions. Outcomes were assessed in a modified intention-to-treat population that included all participants who started both intervention phases and completed all of the in-clinic exercise visits. This trial is registered with ClinicalTrials.gov, NCT03838783, and is complete.

FINDINGS

Between May 15, 2018, and March 5, 2019, we assessed 43 patients for eligibility, of whom 31 were randomly assigned to receive the usual CSII regimen (n=14) or hybrid CSII regimen (n=17) in the first phase (before crossover). The analysis population consisted of 24 participants who completed both study phases. Compared with the usual CSII regimen, participants on the hybrid CSII regimen had a significantly longer time in blood glucose range of 4-10 mmol/L during the 6-h period from the start of both moderate-intensity (mean difference 86 min [95% CI 61-147], p=0·005; percentage time in range 64% [SD 35] vs 40% [35]) and high-intensity in-clinic exercise session (60 min [11-109], p=0·01; 66% [32] vs 50% [27]). Participants on the hybrid CSII regimen also showed a higher time in blood glucose range of 4-10 mmol/L during home-based exercise sessions (mean difference 23 min [95% CI -1 to 46], p=0·055), with significantly lower time spent in hyperglycaemia than participants on the usual CSII regimen (mean difference 25 min [2-48], p=0·04). These exploratory outcomes also showed no significant difference in the amount of time spent in hypoglycaemia, nor the number of hypoglycaemic events, between the two interventions. There were three study-related adverse events reported with the usual CSII regimen (two hypotension events and one nausea event) and four with the hybrid CSII regimen (two hypotension events and two nausea events).

INTERPRETATION

A hybrid regimen of injected insulin degludec and CSII (with pump removal during exercise) appears to be safe and effective in adults with type 1 diabetes who exercise regularly. This approach could offer improved glycaemic control immediately after exercise and should be further assessed in a larger-scale randomised trial.

FUNDING

Novo Nordisk.

0224 Optogenetic Manipulation of Basal Forebrain Parvalbumin Neurons Modulates Vigilant Attention and Rescues Sleep Deprivation Induced Impairments

Introduction

Sleep disruption leads to attention impairments, excessive daytime sleepiness, and is a major contributor to accident rates and decreased workplace productivity. The basal forebrain (BF) region has long been associated with promoting cortical arousal and wakefulness. Recently, selective excitation of BF parvalbumin (PV) GABAergic neurons has been shown to produce high frequency cortical activation and brief periods of wakefulness. Here we test the hypothesis that BF PV neurons are involved in vigilant attention using bidirectional optogenetic manipulations in a signaled reaction time task.

Methods

Brief optogenetic excitation (ChR2) and inhibition (ArchT) of BF PV neurons was applied during a lever release version of the rodent psychomotor vigilance task (rPVT). Mice were trained to hold a lever down to initiate a trial and after a random delay, a 200ms cue light signaled the mouse to quickly release the lever within 1s to receive a sucrose pellet reward. The reaction time between cue light onset and lever release was the primary measure of attentional performance. Sleep deprivation (8h) produced by gentle handling was also investigated. Laser parameters: brief (1s) of continuous (non-pulsatile) laser stimulation was delivered beginning 500ms prior to cue light onset (5mW 473nm blue light for ChR2-mediated excitation; 10mW 530nm green light for ArchT-mediated inhibition).

Results

BF PV excitation led to faster reactions times (N=6, 14% faster, p&lt;.001), interpreted as an enhancement of attention. Sleep deprivation slowed reaction times (20% slower, p&lt;.01) and BF PV excitation rescued the sleep deprivation induced impairments. BF PV inhibition significantly slowed reaction times (25% slower, p&lt;.02), an effect that resembled the effects of sleep deprivation.

Conclusion

This is the first demonstration of a role for BF PV neurons in attention and in the attention deficits produced by sleep deprivation.

Support

T32 HL007901, I01 BX002774, P01 HL095491, R01 MH039683, I01 BX004500, IK2 BX002130, Stonehill College SURE program, I01 BX001356

Paradoxical Rise in Hypoglycemia Symptoms With Development of Hyperglycemia During High-Intensity Interval Training in Type 1 Diabetes

OBJECTIVE

To assess the reliability of self-perception of glycemia during high-intensity interval training (HIIT) in subjects with type 1 diabetes.

RESEARCH DESIGN AND METHODS

This randomized crossover study included subjects who completed four fasted HIIT sessions. Subjects answered the Edinburgh Hypoglycemia Scale, estimated their blood glucose (BG), and had plasma glucose (PG) collected throughout exercise and recovery.

RESULTS

As PG increased throughout exercise, hypoglycemia scores increased across each category: autonomic (3.1-4.4, P < 0.05), neuroglycopenic (1.5-2.4, P < 0.05), and nonspecific (1.3-1.9, P < 0.05). Subjects' estimated BG showed a negative bias that widened as exercise progressed and peaked at -1.6 ± 3.3 mmol/L (P < 0.001) postinsulin correction.

CONCLUSIONS

During HIIT, despite progressing hyperglycemia, subjects experience increased hypoglycemia symptoms and tend to underestimate their BG level.

Optimizing Diabetes Self-management Using the Novel Skills, Confidence, and Preparedness Index (SCPI)

OBJECTIVE

The Skills, Confidence, and Preparedness Index (SCPI) is an electronic tool designed to assess three dimensions (knowledge, confidence, and preparedness) in a clinically relevant measure with immediate feedback to guide the individualization of patient education. This study sought to assess the validity and reliability of the final SCPI generation, its relevance to glycemia, and its responsiveness to patient education.

RESEARCH DESIGN AND METHODS

In Part 1, patients with type 1 and type 2 diabetes were recruited from specialist clinics over a 6-month period and completed the 23-item SCPI using a tablet. In Part 2, participants also underwent a diabetes self-management education (DSME) program. Baseline SCPI score was used to guide the DSME, and SCPI and glycemia were assessed at completion.

RESULTS

In total, 423 patients met inclusion criteria and 405 had evaluable data. SCPI scores were found to have a high degree of validity, internal consistency, and test-retest reliability, with no floor or ceiling effects. Scoring was negatively correlated with HbA_1c (type 1 diabetes: r = -0.26, P = 0.001; type 2 diabetes: r = -0.20, P = 0.004). In 51 participants who underwent a DSME intervention (6.4 ± 0.6 visits over a mean ± SD 3.4 ± 0.8 months), mean HbA_1c improvement was 1.2 ± 0.2% (13.1 ± 2.2 mmol/mol, P < 0.0001). Total SCPI score and each subscore improved in parallel.

CONCLUSIONS

The SCPI tool is a quick and easy-to-use measurement of three domains: skills, confidence, and preparedness. The instant scoring and feedback and its relationship to glycemic control should improve the efficiency and quality of individualizing care in the diabetes clinic.

Patient Reported Outcomes following initiation of Glucagon-like peptide-1 Receptor agonists in patients with type 2 Diabetes in a specialist endocrinology practice of the LMC diabetes registry: The PROGRESS-Diabetes study

AIMS

To compare patient-reported outcomes and clinical outcomes in patients who initiated dulaglutide or liraglutide as part of usual clinical therapy.

METHODS

This observational study enrolled adults with type 2 diabetes who initiated dulaglutide or liraglutide between April 2017 and January 2018. A prospective patient cohort completed questionnaires at baseline and at their usual follow-up visit three to six months later. Clinical outcomes were assessed in a post-hoc retrospective analysis using propensity score matching.

RESULTS

In the per-protocol analysis, 146 dulaglutide and 79 liraglutide patients had similar significant improvements in diabetes treatment satisfaction scores (dulaglutide 9.6 ± 1.1, p < 0.001; liraglutide 10.6 ± 1.4, p < 0.001) and follow-up scores for diabetes device satisfaction. Only dulaglutide had significant improvements in medication adherence scores. In the overall cohort, 754 matched patients showed similar reductions in A1C (dulaglutide -0.8% [9 mmol/mol]; liraglutide -0.7% [8 mmol/mol]). Liraglutide patients had a greater reduction in weight than those initiating dulaglutide (-2.8 kg vs. -1.8 kg; p < 0.001).

CONCLUSIONS

Patients who initiated dulaglutide or liraglutide in a real-world specialist practice had similar improvements in diabetes medication satisfaction and diabetes device satisfaction. Only dulaglutide patients had significant improvements in medication adherence scores. Both treatment cohorts had similar patterns of A1C change, and liraglutide had significantly greater weight loss, which are similar to findings from clinical trials.

Real-World Health Outcomes of Insulin Glargine 300 U/mL vs Insulin Glargine 100 U/mL in Adults With Type 1 and Type 2 Diabetes in the Canadian LMC Diabetes Patient Registry: The REALITY Study

OBJECTIVES

This study evaluated real-world clinical outcomes of patients with type 1 diabetes (T1D) and type 2 diabetes (T2D) initiating or transferring to insulin glargine 300 U/mL (Gla-300) vs insulin glargine 100 U/mL (Gla-100).

METHODS

This is a retrospective cohort study using data from the Canadian LMC Diabetes Patient Registry. The 4 following cohorts were analyzed: 1) insulin-naïve patients with T2D who initiated Gla-300 or Gla-100, 2) patients with T2D who switched from neutral protamine Hagedorn (NPH) or detemir to Gla-300 or Gla-100, 3) patients with T2D who switched from Gla-100 to Gla-300 and 4) patients with T1D who switched from Gla-100, NPH or detemir to Gla-300.

RESULTS

Of 376 propensity score-matched insulin-naïve patients, 6-month reduction in glycated hemoglobin (A1C) was similar between Gla-300 (-1.78%±1.85%; p<0.001) and Gla-100 (-1.74%±1.87%; p<0.001). In 114 propensity score-matched patients who switched from NPH or detemir, 6-month reduction in A1C was similar between Gla-300 (-0.78%±1.14%) and Gla-100 (-0.70%±1.57%). The 396 patients who switched from Gla-100 to Gla-300 had a significant reduction in A1C (-0.45%±1.39%; p<0.001). In 196 patients with T1D who switched from Gla-100, NPH or detemir to Gla-300, there was a significant reduction in A1C of -0.17%±1.19% (p=0.04).

CONCLUSIONS

In a real-world clinical setting, insulin-naïve patients who initiated Gla-300 or Gla-100 showed similar changes in A1C and weight. Patients with T1D or T2D using Gla-300 transferred from another basal insulin had significant reductions in A1C with no change in weight or insulin dose.

Time Lag and Accuracy of Continuous Glucose Monitoring During High Intensity Interval Training in Adults with Type 1 Diabetes

Background: This study investigated the accuracy of real-time continuous glucose monitoring (rtCGM) during high intensity interval training (HIIT) in patients with type 1 diabetes (T1D). Methods: Seventeen participants with T1D, using multiple daily injections (MDI) with basal insulin glargine 300 U/mL (Gla-300), completed four fasted HIIT sessions over 4 weeks while wearing a Dexcom rtCGM G4 Platinum system. Each exercise consisted of high intensity interval cycling and multimodal training over 25 min. Reference venous plasma glucose (PG) was measured at 60- and 10-min before exercise (Stage 1), every 10 min during exercise and then every 15 min until 180 min after the end of exercise (Stage 2: during exercise and 45-min early recovery; Stage 3: 45 min to 3 h after the end of exercise); and at 6-, 10-, and 13-h postexercise (Stage 4). Results: In the 64 HIIT sessions that resulted in hyperglycemia, PG increased 90.0 ± 32.4 mg/dL (mean ± standard deviation), peaking at 68.0 ± 18.4 min from the start of HIIT. Mean absolute relative difference was highest during exercise and early recovery (Stage 2) at 17.8%, versus Stage 1 (10.4%), Stage 3 (10.6%), and Stage 4 (11.5%) (P < 0.001). During Stage 2, rtCGM showed a significant negative bias of 35.3 mg/dL (P < 0.001) compared to reference glucose. Lag time to reach the half-maximal glucose rise was 35 min in rtCGM versus PG. The Surveillance Error Grid found that in Stage 2, only 65.5% of paired values were in the no-risk zone and the %15/15 was 50%, significantly lower than the other stages (P < 0.001). Conclusions: During HIIT and early recovery, there is an increase in lag time and a related decline in accuracy of Dexcom rtCGM G4, compared to pre-exercise and later recovery, in patients with T1D using MDI.

Reproducibility in the cardiometabolic responses to high-intensity interval exercise in adults with type 1 diabetes

AIMS

Patients with type 1 diabetes (T1D) often report a rise in their blood glucose level following brief intense exercise. We sought to determine the reproducibility of the cardiometabolic responses to high-intensity interval training (HIIT).

METHODS

Sixteen adults with T1D, using an optimized multiple daily injection with basal insulin glargine 300 U/mL (Gla-300), performed four fasted HIIT sessions over a 4-6-week period. Exercise consisted of high-intensity interval cycling and multimodal training over 25 min.

RESULTS

Heart rate and rating of perceived exertion rose similarly in all sessions, as did lactate, catecholamine and growth hormone levels. Plasma glucose increased in response to HIIT in 62 of 64 visits (97%), with an overall increase of 3.7 ± 1.6 mmol/L (Mean ± SD) (P < 0.001). In within-patient comparisons, the change in plasma glucose among the four HIIT sessions was significantly correlated with a composite correlation of 0.58 ([r² = 0.34]; 95% CI 0.35-0.80; P < 0.01).

CONCLUSIONS

Intersession observations of four separate HIIT sessions showed high intrasubject reproducibility in the cardiometabolic responses to exercise, including the rise in plasma glucose, when adults with T1D perform the activity in a fasted state.

Optimal Insulin Correction Factor in Post-High-Intensity Exercise Hyperglycemia in Adults With Type 1 Diabetes: The FIT Study

OBJECTIVE

Postexercise hyperglycemia, following high-intensity interval training (HIIT) in patients with type 1 diabetes (T1D), is largely underrecognized by the clinical community and generally undertreated. The aim of this study was to compare four multipliers of an individual's insulin correction factor (ICF) to treat post-HIIT hyperglycemia.

RESEARCH DESIGN AND METHODS

The FIT study had a randomized, crossover design in physically active subjects with T1D (mean ± SD age 34.9 ± 10.1 years, BMI 25.5 ± 2.5 kg/m², and HbA_1c 7.2 ± 0.9%) using multiple daily injections. Following an 8-week optimization period, with 300 units/mL insulin glargine used as the basal insulin, subjects performed four weekly sessions of 25 min of HIIT. If hyperglycemia (>8.0 mmol/L) resulted, subjects received a bolus insulin correction 15 min post-HIIT, based on their own ICF, adjusted by one of four multipliers: 0, 50, 100, or 150%.

RESULTS

Seventeen subjects completed 71 exercise trials, of which 64 (90%) resulted in hyperglycemia. At 40 min postexercise, plasma glucose (PG) increased from mean ± SD 8.8 ± 1.0 mmol/L at baseline to 12.7 ± 2.4 mmol/L (increase of 3.8 ± 1.5 mmol/L). After correction, adjusted mean ± SE PG was significantly reduced for the 50% (-2.3 ± 0.8 mmol/L, P < 0.01), 100% (-4.7 ± 0.8 mmol/L, P < 0.001), and 150% (-5.3 ± 0.8 mmol/L, P < 0.001) arms but had increased further in the 0% correction arm. Both the 100 and 150% corrections were more effective than the 50% correction (P < 0.01 and P < 0.001, respectively) but were not different from each other. Hypoglycemia was rare.

CONCLUSIONS

In post-HIIT hyperglycemia, correction based on a patient's usual ICF is safe and effective. Optimal PG reduction, with minimal hypoglycemia, occurred in the 100 and 150% correction arms.

Assessment of self-management in patients with diabetes using the novel LMC Skills, Confidence and Preparedness Index (SCPI)

AIMS

The LMC Skills, Confidence & Preparedness Index (SCPI) is an electronic tool designed to meet ISOQOL standards and (a) assess three dimensions: knowledge, confidence and preparedness; (b) provide a clinically meaningful measure; (c) provide immediate feedback to the healthcare provider. Internal consistency and external validity have been previously reported in a refractory diabetes cohort. This larger evaluation, broader in glycemic control, sought to assess clinical relevance to glycemia.

METHODS

Participants with type 1 and type 2 diabetes were recruited from LMC Diabetes and Endocrinology specialist clinics, from April to October 2016. Participants completed the SCPI using a tablet. Demographic and laboratory data were extracted from the LMC Diabetes Patient Registry.

RESULTS

In total, 529 patients met inclusion criteria and were included in psychometric analyses; 518 patients with established diabetes (>6 months) were assessed for SCPI - glycemia correlations. SCPI scores were found to have a high degree of validity, internal consistency, and test-retest reliability. Most importantly, the tool showed good external validity in its relation to glycemic control, both in tertile analysis, demonstrating a threshold effect consistent with a 'moderate' degree of poor control; and in overall correlation with HbA1c for the total SCPI score and two subscales (Skills and Confidence).

CONCLUSIONS

The SCPI tool is a quick (25 items), easy to use measure of three domains - knowledge, confidence and preparedness. The instant scoring and specific feedback, as well as the relationship to glycemic control should provide significant value in the patient assessment in the diabetes clinic.

Waist circumference at five common measurement sites in normal weight and overweight adults: which site is most optimal?

The aim of this study was to determine (i) if adults would measure their own waist circumference (WC), (ii) which WC site(s) are the most intuitive and easy to measure and (iii) if measurement accuracy and association between WC and blood pressure differs across five measurement sites. Participants (n = 198) measured their WC first with no instruction and then using visual instructions for the iliac crest, last rib, midpoint, minimal waist and umbilicus. Without instruction, men most commonly measured their WC at the umbilicus and iliac crest, while women measured their WC at the umbilicus and minimal WC. Both men and women reported the minimal waist and umbilicus to be moderately easier to self-measure compared to the other sites (P < 0.05). Prevalence of abdominal obesity varied significantly by gender and measurement site, especially for females (normal weight: 0-18%; overweight: 51-79%). Measurement site did not influence accuracy of WC self-measurement or the association between WC and blood pressure (P > 0.05). A universal WC landmark is needed. From these results, there does not appear to be a clear clinical advantage in terms of blood pressure or practical advantage of measuring one WC site over another. However, the umbilicus may be the most intuitive and easy to measure.

Association between cardiorespiratory fitness and metabolic risk factors in a population with mild to severe obesity

Background

Previous literature suggests the beneficial effects of fitness on abdominal obesity may be attenuated in obesity and abolished in severe obesity. It is unclear whether the beneficial association between fitness and health is similarly present in those with mild and severe obesity.

Methods

Patients from the Wharton Medical Clinic (n = 853) completed a clinical examination and maximal treadmill test. Patients were categorized into fit and unfit based on age- and sex-categories and body mass index (BMI) class (mild: ≤ 34.9 kg/m², moderate: 35–39.9 kg/m² or severe obesity: ≥ 40 kg/m²).

Results

Within the sample, 41% of participants with mild obesity had high fitness whereas only 25% and 11% of the participants with moderate and severe obesity, respectively, had high fitness. BMI category was independently associated with most of the metabolic risk factors, while fitness was only independently associated with systolic blood pressure and triglycerides (P < 0.05). The prevalent relative risk for pre-clinical hypertension, hypertriglyceridemia and hypoalphalipoproteinemia and pre-diabetes was only elevated in the unfit moderate and severe obesity groups (P < 0.05), and fitness groups were only significantly different in their relative risk for prevalent pre-clinical hypertension within the severe obesity group (p = 0.03). High fitness was associated with smaller waist circumferences, with differences between high and low fitness being larger in those with severe obesity than mild obesity (Men: P = 0.06, Women: P = 0.0005).

Conclusions

Thus, in contrast to previous observations, the favourable associations of having high fitness and health may be similar if not augmented in individuals with severe compared to mild obesity.

Effect of Dapagliflozin on Glycemic Control, Weight, and Blood Pressure in Patients with Type 2 Diabetes Attending a Specialist Endocrinology Practice in Canada: A Retrospective Cohort Analysis

BACKGROUND

In randomized clinical trials, dapagliflozin has been shown to improve glycemic control, weight, and blood pressure. However, there is little real-world evidence of the effectiveness of dapagliflozin. The objective of this study is to investigate the real-world treatment outcomes of patients with type 2 diabetes (T2D) who initiated dapagliflozin in a referral-based endocrinology practice.

METHODS

This study was a retrospective cohort analysis of patients with T2D who initiated dapagliflozin in 2015, using data from a large, specialist diabetes registry in Canada.

RESULTS

1520 patients were eligible for analysis. Following 3 to 6 months of treatment, hemoglobin A1c (HbA1c) decreased by a mean of 0.9% ± 1.3% (9.8 ± 14.2 mmol/mol) (P < 0.01), weight decreased 2.2 ± 3.1 kg (P < 0.01), and systolic blood pressure decreased 3.7 ± 14.3 mmHg (P < 0.01). The proportion of patients who achieved glycemic control (HbA1c ≤7.0%) increased from 7.0% at baseline to 27.0% during follow-up. There was also a statistically significant decrease from baseline in body mass index, diastolic blood pressure, fasting glucose, total cholesterol, low-density lipoprotein cholesterol, triglycerides, alanine aminotransferase, and the proportion of patients with microalbuminuria (P < 0.01). A higher baseline HbA1c, shorter duration of diabetes, male gender, and greater weight loss were each independently associated with a greater reduction in HbA1c (P < 0.01).

CONCLUSIONS

In a real-world clinical setting in Canada, dapagliflozin produced significant improvements in HbA1c, weight, and blood pressure in patients with T2D, comparable to that seen in randomized clinical trials.

The LMC Skills, Confidence & Preparedness Index (SCPI): development and evaluation of a novel tool for assessing self-management in patients with diabetes

BACKGROUND

Optimal diabetes care requires a specific set of self-management behaviours. The purpose of this study was to present the development and initial psychometric evaluation of a new tool to measure three key aspects of a patient's diabetes self-management: knowledge of the skill, confidence in being able to perform the skill and preparedness to implement the skill.

METHODS

A sequential exploratory mixed-methods design was used. A panel of educators, researchers and clinicians established a scale with items that would adequately capture skills, confidence and preparedness in seven core health behaviours central to diabetes care. The psychometric properties of the items were pilot tested on 120 participants with diabetes from a tertiary referral centre, and repeated 6 months later on 70 participants. Item selection was informed by factor analysis, item-total statistics and the need for brevity.

RESULTS

Twenty five items from a pool of 36 were retained, with an excellent overall intraclass correlation (ICC) of 0.94 (95% CI 0.92-0.99; p < 0.001). Internal consistency for the subscales (skills-9 items, confidence - 8 items, preparedness - 8 items) was very good (intraclass correlation between 0.83 and 0.88), and retest reliability after 6 months was also good (r = 0.48; p < 0.01). The scale was positively correlated to established scales that assess skill (Michigan Diabetes Knowledge Test) (r = 0.21;p = 0.01), and assess skill and confidence (Diabetes Empowerment Scale) (r = 0.28;p < 0.01).

CONCLUSIONS

The Skills, Confidence & Preparedness Index is a brief and easy to administer new scale that is more comprehensive than existing tools. It should be used to assess self-management in patients with diabetes, optimize the resources applied to each patient, and determine educational needs and direct clinical management. The scale should be further evaluated in a broader population of patients with diabetes.

Calorie Estimation in Adults Differing in Body Weight Class and Weight Loss Status

PURPOSE

Ability to accurately estimate calories is important for weight management, yet few studies have investigated whether individuals can accurately estimate calories during exercise or in a meal. The objective of this study was to determine if accuracy of estimation of moderate or vigorous exercise energy expenditure and calories in food is associated with body weight class or weight loss status.

METHODS

Fifty-eight adults who were either normal weight (NW) or overweight (OW), and either attempting (WL) or not attempting weight loss (noWL), exercised on a treadmill at a moderate (60% HRmax) and a vigorous intensity (75% HRmax) for 25 min. Subsequently, participants estimated the number of calories they expended through exercise and created a meal that they believed to be calorically equivalent to the exercise energy expenditure.

RESULTS

The mean difference between estimated and measured calories in exercise and food did not differ within or between groups after moderate exercise. After vigorous exercise, OW-noWL overestimated energy expenditure by 72% and overestimated the calories in their food by 37% (P < 0.05). OW-noWL also significantly overestimated exercise energy expenditure compared with all other groups (P < 0.05) and significantly overestimated calories in food compared with both WL groups (P < 0.05). However, among all groups, there was a considerable range of overestimation and underestimation (-280 to +702 kcal), as reflected by the large and statistically significant absolute error in calorie estimation of exercise and food.

CONCLUSIONS

There was a wide range of underestimation and overestimation of calories during exercise and in a meal. Error in calorie estimation may be greater in overweight adults who are not attempting weight loss.

Neuromuscular responses of the plantar flexors to whole-body vibration

Enhanced physical performance following whole-body vibration (WBV) has been attributed to increased muscle activity; however, few studies have measured the mechanisms underlying these changes. The objective of this study was to measure the responsiveness of the Ia pathway as well as contractile properties in 16 young adults (24±2 years, eight men, eight women) following repeated bouts of acute WBV (45 Hz, 2 mm). Hoffman reflexes (H-reflex), compound muscle action potentials (M-wave), and twitch contractile properties were measured prior to and immediately following five 1-minute WBV exposures, and at 3, 5, 10, and 20 minute post-WBV. M-wave and H-reflex amplitudes decreased by 8% (P<.001) and by 46% (P<.05), respectively, whereas peak twitch torque decreased by 9% (P<.01) and rate of twitch torque development slowed 8% (P<.05). Percent voluntary activation and maximal plantar flexor torque were unchanged as a consequence of WBV (P>.05). In response to acute WBV, the root mean square of the soleus electromyography signal (EMG_RMS ) increased by 8%, while the EMG_RMS of the lateral gastrocnemius increased by 3% (P<.05). These data indicate that the responsiveness of the Ia pathway is diminished and contractile function is impaired immediately following WBV, and that the neural mechanisms underlying improved performance following WBV lie in alternative hypotheses possibly involving spindle disfacilitation or Golgi afferent modulation.

Specialist-Led Diabetes Registries and Prevalence of Poor Glycemic Control in Type 2 Diabetes: The Diabetes Registry Outcomes Project for A1C Reduction (DROP A1C)

OBJECTIVE

To highlight the utility of a large patient registry to identify functionally refractory patients (persistent HbA1c ≥75 mmol/mol [9.0%]) with type 2 diabetes, identify their barriers to glycemic control, and implement barrier-specific care path strategies to improve glycemic control.

RESEARCH DESIGN AND METHODS

A working group developed a structured tool to optimize the collection of information on barriers to glycemic control and designed structured care paths to address each barrier. Participants were identified from a large Canadian registry and were assigned to a certified diabetes educator (CDE) as their case manager for a 12-month period to coordinate assessment of their barriers and to implement appropriate care path strategies. The primary outcome measure was the mean change in HbA1c from baseline at 12 months.

RESULTS

Overall, 3,662 refractory patients were initially identified of whom 1,379 were eligible for inclusion and 155 enrolled. The most common barrier categories participants identified were psychological/support (93%), socioeconomic (87%), and accessibility (82%), with high concordance (75-94%) between participant and CDE. No specific barriers were predictive of hyperglycemia. After implementation of barrier-specific care paths, the mean reduction in HbA1c at 12 months was 17 mmol/mol (1.5%; P < 0.01 vs. baseline) versus only 5 mmol/mol (0.5%) in the source cohort (n = 966) who continued with standard care. The incidence of severe hypoglycemia did not change significantly during the study.

CONCLUSIONS

In registry-identified hyperglycemic patients with type 2 diabetes, the use of barrier-specific care paths significantly improved glycemic control in otherwise refractory patients with persistently elevated HbA1c. Further studies using this strategy in other practice settings are warranted.

Aspartame intake is associated with greater glucose intolerance in individuals with obesity

This study examined whether sucrose, fructose, aspartame, and saccharin influences the association between obesity and glucose tolerance in 2856 adults from the NHANES III survey. Aspartame intake significantly influenced the association between body mass index (BMI) and glucose tolerance (interaction: P = 0.004), wherein only those reporting aspartame intake had a steeper positive association between BMI and glucose tolerance than those reporting no aspartame intake. Therefore, consumption of aspartame is associated with greater obesity-related impairments in glucose tolerance.

Associations between visceral fat and liver fat with insulin sensitivity and metabolic risk in obese adolescents

We examined the joint and independent associations between VAT and LF with insulin sensitivity (IS) and lipids in seventy-one obese adolescents (BMI ≥ 95th, 14.9 ± 1.8 years). VAT was assessed by magnetic resonance imaging, and LF was quantified by proton magnetic resonance spectroscopy. IS was evaluated by a 3 -h hyperinsulinemic (80 mU·m−2·min−1) euglycemic clamp. Independent associations between VAT and LF on metabolic variables were assessed in mutually adjusted multivariate models. The joint association between VAT and LF on metabolic variables was assessed by categorizing participants into a low VAT + low LF group (n = 35), high VAT + low LF group (n = 26), or high VAT + high LF group (n = 10), based on a VAT median split (1.17 kg) and high (≥5%) and low (<5%) LF. Both VAT and LF were independently associated with fasting insulin, 2 h insulin, insulin AUC, IS, and triglycerides (P < 0.05). Adolescents with high VAT + high LF had higher 2 h glucose, glucose AUC, 2 h insulin, triglycerides, and lower insulin sensitivity compared to adolescents with high VAT only (P < 0.025 for all). In obese adolescents, VAT and LF were independently associated with insulin sensitivity and dyslipidemia, and the concomitant presence of VAT and LF is strongly associated with metabolic risk factors.

Measurement site influences abdominal subcutaneous and visceral adipose tissue in obese adolescents before and after exercise

BACKGROUND/OBJECTIVES

The objective of this study was to determine if abdominal adipose tissue (AT) measurement site influences the association between baseline and change in abdominal subcutaneous (ASAT) and visceral AT (VAT), and metabolic risk factors in obese adolescents.

METHODS

Fifty-five obese adolescents (14.9 ± 1.7 years; 51% male; 42% white) participated in an aerobic or resistance exercise intervention three times/week for 3 months. We compared the association between changes in abdominal AT area (spanning 5 cm below to 15 cm above L4-L5) and volume measured by magnetic resonance imaging with concomitant changes in metabolic risk.

RESULTS

All AT areas were significantly (p < 0.05) correlated with the respective volume at baseline and follow-up. Baseline VAT areas at 5 and 10 cm above L4-L5 were more strongly associated with VAT volume than VAT area at L4-L5 (p < 0.05). After the intervention, changes in the area at 5 and 10 cm above L4-L5 were more strongly associated with changes in AT volumes than changes in L4-L5 (p < 0.05). Changes in abdominal AT volumes were more strongly associated with insulin area under the curve than any single-slice abdominal AT area.

CONCLUSIONS

The measurement site for abdominal AT has significant influence on the relationships with total VAT or ASAT and metabolic risk factors in obese adolescents before and after an exercise intervention.

Early detection of cerebral glucose uptake changes in the 5XFAD mouse

Brain glucose hypometabolism has been observed in Alzheimer’s disease (AD) patients, and is detected with ¹⁸F radiolabelled glucose, using positron emission tomography. A pathological hallmark of AD is deposition of brain β-amyloid plaques that may influence cerebral glucose metabolism. The five times familial AD (5XFAD) mouse is a model of brain amyloidosis exhibiting AD-like phenotypes. This study examines brain β-amyloid plaque deposition and ¹⁸FDG uptake, to search for an early biomarker distinguishing 5XFAD from wild-type mice. Thus, brain ¹⁸FDG uptake and plaque deposition was studied in these mice at age 2, 5 and 13 months. The 5XFAD mice demonstrated significantly reduced brain ¹⁸FDG uptake at 13 months relative to wild-type controls but not in younger mice, despite substantial β-amyloid plaque deposition. However, by comparing the ratio of uptake values for glucose in different regions in the same brain, 5XFAD mice could be distinguished from controls at age 2 months. This method of measuring altered glucose metabolism may represent an early biomarker for the progression of amyloid deposition in the brain. We conclude that brain ¹⁸FDG uptake can be a sensitive biomarker for early detection of abnormal metabolism in the 5XFAD mouse when alternative relative uptake values are utilized.

Consequences of obesity and weight loss: a devil's advocate position

Obesity is associated with multiple negative health consequences and current weight management guidelines recommend all obese persons to lose weight. However, recent evidence suggests that not all obese persons are negatively affected by their weight and that weight loss does not necessarily always improve health. The purpose of this review is not to trivialize the significant health risks associated with obesity, but to discuss subpopulations of obese people who are not adversely affected, or may even benefit from higher adiposity, and in who weight loss per se may not always be the most appropriate recommendation. More specifically, this review will take a devil's advocate position when discussing the consequences of obesity and weight loss for adults with established cardiovascular disease and type 2 diabetes, weight cyclers, metabolically healthy obese adults, youth, older adults and obese individuals who are highly fit.