IMPAIRED AWARENESS OF HYPOGLYCEMIA CONTINUES TO BE A RISK FACTOR FOR SEVERE HYPOGLYCEMIA DESPITE THE USE OF CONTINUOUS GLUCOSE MONITORING SYSTEM IN TYPE 1 DIABETES

Impact in real-world of intermittent-scanned continuous glucose monitoring with alarms on hypoglycemia and its recognition in type 1 diabetes

BACKGROUND

Recent studies have demonstrated that real-time CGM use reduce the incidence severe hypoglycemic events and impaired awareness of hypoglycemia (IAH) However, there are few real-world studies evaluating the effect of intermittently scanned continuous glucose monitoring (isCGM) on hypoglycemic episodes and hypoglycemia unawareness (IAH). The present study was designed to cover this research-practice gap.

METHODS

This is a real-world, observational, prospective cohort study with 2 years of follow-up in which 60 subjects with T1D who experienced frequent hypoglycemic events were included. All the patients were invited to use isCGM type Abbott FreeStyle Libre 2® on a continuous basis for 2 years. Glucometric parameters were obtained during the initial 2 weeks using isCGM and compared with data collected for the same period at 1 year and at the end of follow-up. The IAH was evaluated using the Clarke questionnaire, and to assess psychological aspects related to hypoglycemia the Hypoglycemia Fear Survey (HFS) was used.

RESULTS

After 2-years of follow-up using isCGM, we observed a decrease in glucose variability (40.3 ± 0.8 % vs. 37.1 ± 0.9 %, p = 0.003), time in low glucose range (54-69 mg/dL) (5.2 ± 0.4 % vs. 3.6 ± 0.3 %, p = 0.001), time in very low glucose range (<54 mg/dL) (3.2 ± 0.5 % vs. 0.8 ± 0.2 %, p < 0.001), less events related to low glucose levels (10.6 ± 1.1 vs 8.0 ± 1.0, p = 0.042) and a short duration of hypoglycemia episodes (106.1 ± 5.9 min vs. 85.7 ± 5.7 min, p = 0.008). In addition, participants presented a reduction of 47 % in the frequency of IAH, assessed by the Clarke questionnaire scores (24.6 % vs. 11.6 %, p = 0.034), as well as hypoglycemia fear (77.8 ± 2.4 vs 68.2 ± 2.1, p < 0.001). Furthermore, a reduction in total insulin dose was also observed (0.64 ± 0.30 UI/Kg/day vs 0.56 ± 0.11 UI/Kg/day, p = 0.018).

CONCLUSIONS

In the real-world, long-term use of isCGM could reduce both hypoglycemic episodes and IAH in people with T1D.

Insulin independence following islet transplantation improves long-term metabolic outcomes

AIMS

Pancreatic islet allotransplantation is an effective therapy for type 1 diabetes mellitus, restoring glycaemic control and hypoglycaemic awareness in patients with recurrent severe hypoglycaemia. Insulin independence following transplant is being increasingly reported; however, this is not a primary endpoint in the UK. Having surpassed 10 years of islet transplantation in Scotland, we aimed to evaluate the impact of insulin independence following transplant on metabolic outcomes and graft survival.

METHODS

We conducted a retrospective analysis on data collected prospectively between 2011 and 2022. Patients who underwent islet transplantation in Scotland up to the 31st January 2020 were included. Primary endpoint was graft survival (stimulated C-peptide >50 pmol/L). Secondary endpoints included GOLD score, HbA1c, C-peptide and insulin requirement. Outcomes were compared between patients who achieved insulin independence at any point following transplant versus those who did not.

RESULTS

60 patients were included. 74.5% experienced >50 severe hypoglycaemic episodes in the year preceding transplant. There was a 55.0% decrease in insulin requirement following transplant and 30.0% achieved insulin independence. Mean graft survival time was 9.0 years (95% CI 7.2-10.9) in patients who achieved insulin independence versus 4.4 years (95% CI 3.4-5.3) in patients who did not. Insulin independence was associated with significantly improved graft function, glycaemic control and hypoglycaemic awareness at 1 year.

CONCLUSIONS

This is the largest UK single-centre study on islet transplant to date. Our findings demonstrate significantly improved outcomes in patients who achieved insulin independence following islet transplantation.

Impact of a 4-week intensive track and field training intervention on glycaemia in adolescents with type 1 diabetes: The ChilDFiT1 study

AIM

To investigate the safety and efficacy of track and field training compared with intensification of insulin treatment only in adolescents with type 1 diabetes (T1D).

MATERIALS AND METHODS

Eighteen adolescents (seven females) with T1D were included (age 15.1 ± 1.1 years, HbA1c 7.3% ± 1.0% [56.3 ± 10.9 mmol/mol]). After a 4-week observational control phase, participants were randomized to either stand-alone intensive glycaemic management (IT; telemedicine or on-site visits, three times/week) or additionally performed track and field exercise (EX; three 60-minute sessions/week) for 4 weeks. Glycaemia was assessed via continuous glucose monitoring during observational control and intervention phases.

RESULTS

Time in range (70-180 mg/dL; 3.9-10.0 mmol/L) significantly improved from the observational control phase to the exercise intervention phase in EX (69% ± 13% vs. 72% ± 11%, P = .049), but not in IT (59% ± 22% vs. 62% ± 16%, P = .399). Time below range 1 (54-69 mg/dL; < 3.9 mmol/L) improved in IT (3.1% ± 1.9% vs. 2.0% ± 0.8%, P = .017) and remained stable in EX (2.0% ± 1.7 vs. 1.9% ± 1.1%, P = .999). The EX group's HbA1c ameliorated preintervention to postintervention (mean difference: ΔHbA1c -0.19% ± 0.17%, P = .042), which was not seen within the IT group (ΔHbA1c -0.16% ± 0.37%, P = .40). Glucose standard deviation was reduced significantly in EX (55 ± 11 vs. 51 ± 10 mg/dL [3.1 ± 0.6 vs. 2.8 ± 0.6 mmol/L], P = .011), but not in IT (70 ± 24 vs. 63 ± 18 mg/dL [3.9 ± 1.3 vs. 3.5 ± 1.0 mmol/L], P = .186).

CONCLUSION

Track and field training combined with intensive glycaemic management improved glycaemia in adolescents with T1D, which was not observed in the non-exercise group.

Pharmacologic inhibition of somatostatin receptor 2 to restore glucagon counterregulation in diabetes

Glucose homeostasis is primarily maintained by pancreatic hormones, insulin and glucagon, with an emerging role for a third islet hormone, somatostatin, in regulating insulin and glucagon responses. Under healthy conditions, somatostatin secreted from pancreatic islet δ-cells inhibits both insulin and glucagon release through somatostatin receptor- induced cAMP-mediated downregulation and paracrine inhibition of β- and α-cells, respectively. Since glucagon is the body's most important anti-hypoglycemic hormone, and because glucagon counterregulation to hypoglycemia is lost in diabetes, the study of somatostatin biology has led to new investigational medications now in development that may help to restore glucagon counterregulation in type 1 diabetes. This review highlights the normal regulatory role of pancreatic somatostatin signaling in healthy islet function and how the inhibition of somatostatin receptor signaling in pancreatic α-cells may restore normal glucagon counterregulation in diabetes mellitus.

Hypoglycaemia symptom frequency, severity, burden, and utility among adults with type 1 diabetes and impaired awareness of hypoglycaemia: Baseline and 24-week findings from the HypoCOMPaSS study

AIMS

To determine the frequency, severity, burden, and utility of hypoglycaemia symptoms among adults with type 1 diabetes (T1D) and impaired awareness of hypoglycaemia (IAH) at baseline and week 24 following the HypoCOMPaSS awareness restoration intervention.

METHODS

Adults (N = 96) with T1D (duration: 29 ± 12 years; 64% women) and IAH completed the Hypoglycaemia Burden Questionnaire (HypoB-Q), assessing experience of 20 pre-specified hypoglycaemia symptoms, at baseline and week 24.

RESULTS

At baseline, 93 (97%) participants experienced at least one symptom (mean ± SD 10.6 ± 4.6 symptoms). The proportion recognising each specific symptom ranged from 15% to 83%. At 24 weeks, symptom severity and burden appear reduced, and utility increased.

CONCLUSIONS

Adults with T1D and IAH experience a range of hypoglycaemia symptoms. Perceptions of symptom burden or utility are malleable. Although larger scale studies are needed to confirm, these findings suggest that changing the salience of the symptomatic response may be more important in recovering protection from hypoglycaemia through regained awareness than intensifying symptom frequency or severity.

Intermittently scanned continuous glucose monitoring and hypoglycaemia awareness in drivers with diabetes: Insights from the Association of British Clinical Diabetologists Nationwide audit

AIM

Frequent hypoglycaemia results in disruption to usual hypoglycaemic autonomic responses leading to impaired awareness of hypoglycaemia, which is associated with an increased risk of severe hypoglycaemia requiring third-party assistance (SH). The UK Driving and Vehicle Licensing Agency (DVLA) does not permit car driving if they have either a complete loss of hypoglycaemia awareness or more than one SH event a year.

METHODS

The FreeStyle Libre (FSL) Association of British Clinical Diabetologists (ABCD) Nationwide Audit consists of data collected by clinicians during routine clinical work, submitted into a secure web-based tool held within the National Health Service (NHS) N3 network. Analysis of paired baseline and follow-up data for people with type 1 diabetes who also held a driving licence was undertaken.

RESULTS

The study consisted of 6304 people who had data recorded about driving status from 102 UK specialist diabetes centres, of which 4218 held a driving licence: 4178 a group 1, standard licence, 33 a group 2, large lorries and buses, seven a taxi licence; 1819 did not drive. Paired baseline and follow-up data were available for a sub-cohort of 1606/4218. At a mean follow-up of 6.9 months [95% CI (6.8, 7.1)], the Gold score had improved (2.3 ± 1.5 vs. 2.0 ± 1.3 p < .001), and the number of people who experienced an SH episode was also significantly lower (12.1% vs. 2.7%, p < .001).

CONCLUSION

This study suggests that intermittently scanned continuous glucose monitoring may improve impaired awareness of hypoglycaemia and reduce the number of people with type 1 diabetes with a driving licence experiencing a severe hypoglycaemic episode.

Impaired Awareness of Hypoglycemia and its Risk Factors among Diabetic Patients in Jazan, Saudi Arabia: A Cross-Sectional Study

BACKGROUND

Impaired awareness of hypoglycemia (IAH) is related to a three- to sixfold increase in the risk of severe hypoglycemia in adults with type 1 diabetes mellitus (T1D). This study aimed to assess the prevalence of IAH and its risk factors and determine the frequency of hypoglycemic symptoms.

OBJECTIVE

This study aimed to assess the prevalence of IAH and its risk factors and determine the frequency of hypoglycemic symptoms.

METHODOLOGY

A cross-sectional study was conducted among T1D patients attending Jazan Endocrine and Diabetes Center in Jazan province, Saudi Arabia. A total of 151 patients participated, using the interview-based Clarke questionnaire, a validated eight-item questionnaire to evaluate IAH. Scoring four or more answers as reduced awareness categorizes the participant as having IAH.

RESULTS

The prevalence of IAH was 25.2% among the T1D patients. IAH was significantly associated with body mass index (BMI; p = 0.034), occupation (p = 0.014), and blood glucose monitoring methods (p = 0.027). Shaking and sweating were the most commonly reported symptoms of hypoglycemia. A BMI of <25 kg/m2 was higher linked to hunger and speech difficulty compared to a BMI of ≥25 kg/m2 (p < 0.05). Changing the insulin injection site was associated with confusion, odd behavior, and speech difficulty (p < 0.05). Monitoring blood glucose four times daily was associated with sweating, odd behavior, and incoordination (p = 0.024) compared to monitoring less than four times daily (p < 0.05). A hemoglobin A1c (HbA1c) reading of ≥7 was linked to odd behavior compared to an HbA1c reading of <7 (p = 0.032). Patients committed to insulin injections were more likely to experience palpitations than non-committed patients (p = 0.038). Each one-unit increase in age, monitoring blood glucose, and income was associated with a decrease in the odds of IAH (OR of Age = 0.89, 95% CI: 0.83-0.95) (OR of income = 0.10, 95% CI: 0.01-0.55). Moreover, individuals with a Body Mass Index (BMI) greater than or equal to 25 (OR = 2.99, 95% CI: 1.13-8.25), employed individuals (OR = 18.2, 95% CI: 3.75-105), and diabetes duration of more than ten years (OR = 3.96, 95% CI: 1.31- 13.2) exhibited an increase in the higher risk of IAH.

CONCLUSION

IAH was prevalent among T1D patients attending Jazan Endocrine and Diabetes Center. The main associated factors included BMI, blood glucose monitoring method, and occupation. Future research should investigate the underlying causes of the observed associations and explore strategies to enhance the awareness of hypoglycemia.

A real-life comparison of hypoglycaemia symptomatology between insulin-treated type 2 diabetes participants with and without impaired awareness of hypoglycaemia

AIMS

We aim to compare and correlate Gold and Clarke questionnaire scores with hypoglycaemic symptomatic responses between insulin-treated type 2 diabetes participants with and without IAH in a real-life study.

METHODS

Insulin-treated type 2 diabetes participants attending an outpatient diabetes clinic in Singapore were asked to complete the Gold and Clarke questionnaires, record capillary blood glucose (CBG) and hypoglycaemic symptoms for 4 weeks.

RESULTS

Data were collected from 153 participants (M:F = 98:55) with mean age 61.0 ± 9.4 years, duration of diabetes 19.5 ± 8.8 years and HbA1c 68 ± 17 mmol/mol (8.4 ± 1.5%). Gold and Clarke methods classified 19.6% and 26.8% of participants with IAH, respectively. Using CBG threshold of <3 mmol/L, significantly greater proportion of participants with intact awareness were experiencing autonomic symptoms than those with IAH with either method (Gold: 69% vs. 18%, p = 0.006; Clarke: 85% vs. 46%, p = 0.010). Significantly greater proportion of participants with IAH experienced no hypoglycaemia symptoms than those with intact awareness (Gold: 3.4% vs. 36%, p = 0.015; Clarke: 3.7% vs. 31%, p = 0.031). Participants with IAH had significantly higher rates of severe hypoglycaemia in the preceding year compared to those without (Gold: 17% vs. 3.3%; Clarke: 15% vs. 2.7%, p = 0.012).

CONCLUSIONS

Gold and Clarke questionnaires are appropriate tools in ascertaining IAH status in insulin-treated type 2 diabetes participants. This is the first time whereby the hypoglycaemia symptomology has robustly validated the Gold and Clarke questionnaire in insulin-treated type 2 diabetes participants.

The impact of hypoglycaemia on quality of life among adults with type 1 diabetes: Results from "YourSAY: Hypoglycaemia"

AIMS

Research on hypoglycaemia and quality of life (QoL) has focused mostly on severe hypoglycaemia and psychological outcomes, with less known about other aspects of hypoglycaemia (e.g., self-treated episodes) and impacts on other QoL domains (e.g., relationships). Therefore, we examined the impact of all aspects of hypoglycaemia on QoL in adults with type 1 diabetes (T1DM).

METHODS

Participants completed an online survey, including assessment of hypoglycaemia-specific QoL (using the 12-item Hypoglycaemia Impact Profile). Mann-Whitney U tests examined differences in hypoglycaemia-specific QoL by hypoglycaemia frequency, severity, and awareness. Hierarchical linear regression examined associations with QoL.

RESULTS

Participants were 1028 adults with T1DM (M ± SD age: 47 ± 15 years; diabetes duration: 27 ± 16 years). Severe and self-treated hypoglycaemia and impaired awareness negatively impacted on overall QoL and several QoL domains, including leisure activities, physical health, ability to keep fit/be active, sleep, emotional well-being, spontaneity, independence, work/studies, and dietary freedom. Diabetes distress was most strongly associated with hypoglycaemia-specific QoL, followed by generic emotional well-being, fear of hypoglycaemia, and confidence in managing hypoglycaemia. Hypoglycaemia frequency and awareness were no longer significantly associated with QoL once psychological factors were considered.

CONCLUSIONS

Hypoglycaemia negatively impacts on several QoL domains. Psychological factors supersede the effect of hypoglycaemia frequency and awareness in accounting for this negative impact.

Current and future therapies to treat impaired awareness of hypoglycemia

In order to achieve optimal glycemic control, intensive insulin regimes are needed for individuals with Type 1 Diabetes (T1D) and insulin-dependent Type 2 Diabetes (T2D). Unfortunately, intensive glycemic control often results in insulin-induced hypoglycemia. Moreover, recurrent episodes of hypoglycemia result in both the loss of the characteristic warning symptoms associated with hypoglycemia and an attenuated counterregulatory hormone responses. The blunting of warning symptoms is known as impaired awareness of hypoglycemia (IAH). Together, IAH and the loss of the hormonal response is termed hypoglycemia associated autonomic failure (HAAF). IAH is prevalent in up to 25% in people with T1D and up to 10% in people with T2D. IAH and HAAF increase the risk of severe hypoglycemia 6-fold and 25-fold, respectively. To reduce this risk for severe hypoglycemia, multiple different therapeutic approaches are being explored that could improve awareness of hypoglycemia. Current therapies to improve awareness of hypoglycemia include patient education and psychoeducation, the use of novel glycemic control technology, pancreas/islet transplantation, and drug therapy. This review examines both existing therapies and potential therapies that are in pre-clinical testing. Novel treatments that improve awareness of hypoglycemia, via improving the counterregulatory hormone responses or improving hypoglycemic symptom recognition, would also shed light on the possible neurological mechanisms that lead to the development of IAH. To reduce the risk of severe hypoglycemia in people with diabetes, elucidating the mechanism behind IAH, as well as developing targeted therapies is currently an unmet need for those that suffer from IAH.

An mHealth Text Messaging Program Providing Symptom Detection Training and Psychoeducation to Improve Hypoglycemia Self-Management: Intervention Development Study

BACKGROUND

Hypoglycemia remains a challenge for roughly 25% of people with type 1 diabetes (T1D) despite using advanced technologies such as continuous glucose monitors (CGMs) or automated insulin delivery systems. Factors impacting hypoglycemia self-management behaviors (including reduced ability to detect hypoglycemia symptoms and unhelpful hypoglycemia beliefs) can lead to hypoglycemia development in people with T1D who use advanced diabetes technology.

OBJECTIVE

This study aims to develop a scalable, personalized mobile health (mHealth) behavioral intervention program to improve hypoglycemia self-management and ultimately reduce hypoglycemia in people with T1D who use advanced diabetes technology.

METHODS

We (a multidisciplinary team, including clinical and health psychologists, diabetes care and education specialists, endocrinologists, mHealth interventionists and computer engineers, qualitative researchers, and patient partners) jointly developed an mHealth text messaging hypoglycemia behavioral intervention program based on user-centered design principles. The following five iterative steps were taken: (1) conceptualization of hypoglycemia self-management processes and relevant interventions; (2) identification of text message themes and message content development; (3) message revision; (4) patient partner assessments for message readability, language acceptability, and trustworthiness; and (5) message finalization and integration with a CGM data-connected mHealth SMS text message delivery platform. An mHealth web-based SMS text message delivery platform that communicates with a CGM glucose information-sharing platform was also developed.

RESULTS

The mHealth SMS text messaging hypoglycemia behavioral intervention program HypoPals, directed by patients' own CGM data, delivers personalized intervention messages to (1) improve hypoglycemia symptom detection and (2) elicit self-reflection, provide fact-based education, and suggest practical health behaviors to address unhelpful hypoglycemia beliefs and promote hypoglycemia self-management. The program is designed to message patients up to 4 times per day over a 10-week period.

CONCLUSIONS

A rigorous conceptual framework, a multidisciplinary team (including patient partners), and behavior change techniques were incorporated to create a scalable, personalized mHealth SMS text messaging behavioral intervention. This program was systematically developed to improve hypoglycemia self-management in advanced diabetes technology users with T1D. A clinical trial is needed to evaluate the program's efficacy for future clinical implementation.

Validating and Establishing a Diagnostic Threshold for the Hypoglycemia Awareness Questionnaire Impaired Awareness Subscale

OBJECTIVE

To evaluate the discriminant and convergent validities of the Hypoglycemia Awareness Questionnaire Impaired Awareness (HypoA-Q IA) subscale and establish a diagnostic threshold for the classification of impaired awareness of hypoglycemia (IAH) in adults with type 1 diabetes (T1D).

METHODS

Twenty-one adults with T1D (male, 48%; median age, 36 years; and T1D duration, 21 years) completed the HypoA-Q IA subscale, Clarke, and hypoglycemia severity (HYPO) scores, continuous glucose monitoring, and hyperinsulinemic hypoglycemic clamp testing. Those with IAH defined by a Clarke score of ≥4 (n = 10) and who experienced severely problematic hypoglycemia and/or marked glycemic lability started automated insulin delivery as part of an 18-month intervention study with the 6-monthly paired assessment of the HypoA-Q IA subscale, Clarke score, HYPO score and continuous glucose monitoring, and hypoglycemic clamp testing at baseline and 6 and 18 months.

RESULTS

The HypoA-Q IA subscale discriminated between those with and without IAH defined by the Clarke score (W = 110.5; P <.001). During intervention, the HypoA-Q IA subscale demonstrated convergent validity via significant relationships with the Clarke (r = 0.72; P <.001) and HYPO (r = 0.60; P <.001) scores; hypoglycemia exposure below 70 (r = 0.53; P <.01), 60 (r = 0.50; P <.01), and 54 (r = 0.48; P <.01) mg/dL; and autonomic symptom (r = -0.53; P <.05), epinephrine (r = -0.68; P <.001), and pancreatic polypeptide (r = -0.52; P <.05) responses to insulin-induced hypoglycemia. The receiver operating characteristic curve analysis revealed that the HypoA-Q IA subscale was an excellent predictor of an abnormal symptom response to insulin-induced hypoglycemia (area under the curve, 0.86) with a score of 12, which was the optimal threshold for IAH classification (sensitivity, 83%; specificity, 80%).

CONCLUSION

These findings support the validity of the HypoA-Q IA subscale and propose a HypoA-Q IA diagnostic threshold to identify IAH in both clinical and research settings.

Prevalence of impaired awareness of hypoglycaemia in people with diabetes mellitus: A systematic review and meta-analysis from 21 countries and regions

AIMS

Impaired awareness of hypoglycaemia (IAH) is a complication of glucose-lowering therapies for diabetes. The purpose of this review was to estimate the pooled prevalence of IAH and unawareness of hypoglycaemia (UAH).

METHODS

We searched the major databases from inception to 8 August 2022 and included all cross-sectional and cohort studies reporting IAH prevalence in people with diabetes. A random-effects model was used to pool effect values. Subgroup analysis and meta-regression were used to identify study-level characteristics affecting prevalence.

RESULTS

Sixty-two studies from 21 countries published between 2000 and 2022 were included, with 39,180 participants (type 1 diabetes: 19,304 vs. Type 2 diabetes: 14,650). The pooled prevalence was 23.2% (95% CI: 18.4%-29.3%) via the Clarke questionnaire, 26.2% (95% CI: 22.9%-29.9%) via the Gold score, and 58.5% (95% CI: 53.0%-64.6%) via the Pedersen-Bjergaard method, all from studies classified as presenting a moderate and low risk of bias. The prevalence of IAH was generally higher in people with type 1 diabetes than in those with type 2 diabetes and lowest in Europe. Meta-regression results show that the duration of diabetes was a factor influencing the prevalence of IAH. The prevalence of UAH by the Pedersen-Bjergaard method was 17.6 (95% CI: 14.9%-20.3%).

CONCLUSIONS

IAH is a prevalent risk event among people with type 1 and type 2 diabetes, showing clinical heterogeneity and regional variability. UAH, an adverse progression of IAH, is also a serious burden. More primary research on the prevalence of IAH is needed in areas with a high diabetes burden.

Development and Validation of an Electronic Health Record-Based Risk Assessment Tool for Hypoglycemia in Patients With Type 2 Diabetes Mellitus

BACKGROUND

The recent availability of high-quality data from clinical trials, together with machine learning (ML) techniques, presents exciting opportunities for developing prediction models for clinical outcomes.

METHODS

As a proof-of-concept, we translated a hypoglycemia risk model derived from the Action to Control Cardiovascular Risk in Diabetes (ACCORD) study into the HypoHazardScore, a risk assessment tool applicable to electronic health record (EHR) data. To assess its performance, we conducted a 16-week clinical study at the University of Minnesota where participants (N = 40) with type 2 diabetes mellitus (T2DM) had hypoglycemia assessed prospectively by continuous glucose monitoring (CGM).

RESULTS

The HypoHazardScore combines 16 risk factors commonly found within the EHR. The HypoHazardScore successfully predicted (area under the curve [AUC] = 0.723) whether participants experienced least one CGM-assessed hypoglycemic event (glucose <54 mg/dL for ≥15 minutes from two CGMs) while significantly correlating with frequency of CGM-assessed hypoglycemic events (r = 0.38) and percent time experiencing CGM-assessed hypoglycemia (r = 0.39). Compared to participants with a low HypoHazardScore (N = 19, score <4, median score of 4), participants with a high HypoHazardScore (N = 21, score ≥4) had more frequent CGM-assessed hypoglycemic events (high: 1.6 ± 2.2 events/week; low: 0.3 ± 0.5 events/week) and experienced more CGM-assessed hypoglycemia (high: 1.4% ± 2.0%; low: 0.2% ± 0.4% time) during the 16-week follow-up.

CONCLUSIONS

We demonstrated that a hypoglycemia risk model can be successfully adapted from the ACCORD data to the EHR, with validation by a prospective study using CGM-assessed hypoglycemia. The HypoHazardScore represents a significant advancement toward implementing an EHR-based decision support system that can help reduce hypoglycemia in patients with T2DM.

Ghrelin does not impact the blunted counterregulatory response to recurrent hypoglycemia in mice

Introduction

Recurrent episodes of insulin-induced hypoglycemia in patients with diabetes mellitus can result in hypoglycemia-associated autonomic failure (HAAF), which is characterized by a compromised response to hypoglycemia by counterregulatory hormones (counterregulatory response; CRR) and hypoglycemia unawareness. HAAF is a leading cause of morbidity in diabetes and often hinders optimal regulation of blood glucose levels. Yet, the molecular pathways underlying HAAF remain incompletely described. We previously reported that in mice, ghrelin is permissive for the usual CRR to insulin-induced hypoglycemia. Here, we tested the hypothesis that attenuated release of ghrelin both results from HAAF and contributes to HAAF.

Methods

C57BL/6N mice, ghrelin-knockout (KO) + control mice, and GhIRKO (ghrelin cell-selective insulin receptor knockout) + control mice were randomized to one of three treatment groups: a "Euglycemia" group was injected with saline and remained euglycemic; a 1X hypoglycemia ("1X Hypo") group underwent a single episode of insulin-induced hypoglycemia; a recurrent hypoglycemia ("Recurrent Hypo") group underwent repeated episodes of insulin-induced hypoglycemia over five successive days.

Results

Recurrent hypoglycemia exaggerated the reduction in blood glucose (by ~30%) and attenuated the elevations in plasma levels of the CRR hormones glucagon (by 64.5%) and epinephrine (by 52.9%) in C57BL/6N mice compared to a single hypoglycemic episode. Yet, plasma ghrelin was equivalently reduced in "1X Hypo" and "Recurrent Hypo" C57BL/6N mice. Ghrelin-KO mice exhibited neither exaggerated hypoglycemia in response to recurrent hypoglycemia, nor any additional attenuation in CRR hormone levels compared to wild-type littermates. Also, in response to recurrent hypoglycemia, GhIRKO mice exhibited nearly identical blood glucose and plasma CRR hormone levels as littermates with intact insulin receptor expression (floxed-IR mice), despite higher plasma ghrelin in GhIRKO mice.

Conclusions

These data suggest that the usual reduction of plasma ghrelin due to insulin-induced hypoglycemia is unaltered by recurrent hypoglycemia and that ghrelin does not impact blood glucose or the blunted CRR hormone responses during recurrent hypoglycemia.

Patient-Reported Usefulness and Challenges in Using Hypoglycemia-Informing Features of Continuous Glucose Monitors to Manage Hypoglycemia

PURPOSE

The purpose of this study series, which involves a questionnaire survey and qualitative interviews, was to (a) evaluate patient-reported usefulness of continuous glucose monitor (CGM) hypoglycemia-informing features and (b) identify challenges in using these features (ie, CGM glucose numbers, trend arrows, trend graphs, and hypoglycemia alarms) during hypoglycemia in adults with type 1 diabetes (T1DM).

METHODS

A cross-sectional questionnaire survey study was conducted with adults who have T1DM and were using CGMs to assess the perceived usefulness of hypoglycemia-informing features. A semistructured interview study with T1DM CGM-using adults and inductive thematic analysis were subsequently performed to identify challenges in using CGM hypoglycemia-informing features to manage hypoglycemia.

RESULTS

In the survey study (N = 252), the CGM glucose numbers, trend arrows, trend graphs, and hypoglycemia alarms were found to be very useful by 79%, 70%, 43%, and 64% of participants, respectively. Several challenges in using these features to manage hypoglycemia were identified in the qualitative study (N = 23): (1) hypoglycemia information not fully reliable,; (2) unpredictability of future blood glucose levels, (3) lack of awareness about how information can be used, and (4) disruptions associated with information.

CONCLUSIONS

Although the majority of T1DM adults found their CGMs' hypoglycemia-informing features helpful, challenges in optimally using these features persisted. Targeted knowledge and behavioral interventions could improve CGM use to reduce hypoglycemia.

Protective and risk factors of impaired awareness of hypoglycemia in patients with type 1 diabetes: a cross-sectional analysis of baseline data from the PR-IAH study

BACKGROUND

Hypoglycemia in type 1 diabetes (T1D) is associated with mortality and morbidity, especially when awareness of hypoglycemia is impaired. This study aimed to investigate the protective and risk factors for impaired awareness of hypoglycemia (IAH) in adults with T1D.

METHODS

This cross-sectional study enrolled 288 adults with T1D (mean age, 50.4 ± 14.6 years; male, 36.5%; diabetes duration, 17.6 ± 11.2 years; mean HbA1c level, 7.7 ± 0.9%), who were divided into IAH and non-IAH (control) groups. A survey was conducted to assess hypoglycemia awareness using the Clarke questionnaire. Diabetes histories, complications, fear of hypoglycemia, diabetes distress, hypoglycemia problem-solving abilities, and treatment data were collected.

RESULTS

The prevalence of IAH was 19.1%. Diabetic peripheral neuropathy was associated with an increased risk of IAH (odds ratio [OR] 2.63; 95% confidence interval [CI] 1.13-5.91; P = 0.014), while treatment with continuous subcutaneous insulin infusion and hypoglycemia problem-solving perception scores were associated with a decreased risk of IAH (OR, 0.48; 95% CI, 0.22-0.96; P = 0.030; and OR, 0.54; 95% CI, 0.37-0.78; P = 0.001, respectively). There was no difference in continuous glucose monitoring use between the groups.

CONCLUSION

We identified protective factors in addition to risk factors for IAH in adults with T1D. This information may help manage problematic hypoglycemia.

TRIAL REGISTRATION

University hospital Medical Information Network (UMIN) Center: UMIN000039475). Approval date 13 February 2020.

Commentary to accompany Flatt et al., Automated insulin delivery for hypoglycemia avoidance and glucose counterregulation in longstanding type 1 diabetes with hypoglycemia unawareness

N/A.

Changes in attitudes to awareness of hypoglycaemia during a hypoglycaemia awareness restoration programme are associated with avoidance of further severe hypoglycaemia episodes within 24 months: the A2A in HypoCOMPaSS study

AIMS/HYPOTHESIS

The aims of this study were to assess cognitions relating to hypoglycaemia in adults with type 1 diabetes and impaired awareness of hypoglycaemia before and after the multimodal HypoCOMPaSS intervention, and to determine cognitive predictors of incomplete response (one or more severe hypoglycaemic episodes over 24 months).

METHODS

This analysis included 91 adults with type 1 diabetes and impaired awareness of hypoglycaemia who completed the Attitudes to Awareness of Hypoglycaemia (A2A) questionnaire before, 24 weeks and 24 months after the intervention, which comprised a short psycho-educational programme with optimisation of insulin therapy and glucose monitoring.

RESULTS

The age and diabetes duration of the participants were 48±12 and 29±12 years, respectively (mean±SD). At baseline, 91% reported one or more severe hypoglycaemic episodes over the preceding 12 months; this decreased to <20% at 24 weeks and after 24 months (p=0.001). The attitudinal barrier 'hyperglycaemia avoidance prioritised' (η²_p=0.250, p=0.001) decreased from baseline to 24 weeks, and this decrease was maintained at 24 months (mean±SD=5.3±0.3 vs 4.3±0.3 vs 4.0±0.3). The decrease in 'asymptomatic hypoglycaemia normalised' from baseline (η²_p=0.113, p=0.045) was significant at 24 weeks (1.5±0.3 vs 0.8±0.2). Predictors of incomplete hypoglycaemia response (one or more further episodes of severe hypoglycaemia) were higher baseline rates of severe hypoglycaemia, higher baseline scores for 'asymptomatic hypoglycaemia normalised', reduced change in 'asymptomatic hypoglycaemia normalised' scores at 24 weeks, and lower baseline 'hypoglycaemia concern minimised' scores (all p<0.05).

CONCLUSIONS/INTERPRETATION

Participation in the HypoCOMPaSS RCT was associated with improvements in hypoglycaemia-associated cognitions, with 'hyperglycaemia avoidance prioritised' most prevalent. Incomplete prevention of subsequent severe hypoglycaemia episodes was associated with persistence of the cognition 'asymptomatic hypoglycaemia normalised'. Understanding and addressing cognitive barriers to hypoglycaemia avoidance is important in individuals prone to severe hypoglycaemia episodes.

CLINICAL TRIALS REGISTRATION

www.isrctn.org : ISRCTN52164803 and https://eudract.ema.europa.eu : EudraCT2009-015396-27.

Fall in prevalence of impaired awareness of hypoglycaemia in individuals with type 1 diabetes

AIMS

Impaired awareness of hypoglycaemia (IAH) has been reported to affect up to a third of people with type 1 diabetes. Whether the increased use of sensor technology has changed its prevalence remains unknown. The aim of this study was to investigate the current prevalence of IAH and its change over time in a cohort of individuals with type 1 diabetes.

METHODS

IAH was assessed using the modified Clarke questionnaire in adults with type 1 diabetes. Participants were recruited from the diabetes outpatient clinic from February 2020 through April 2021. The scores were compared to similar data collected during previous assessments in 2006, 2010 and 2016 respectively.

RESULTS

A total of 488 individuals (51.2% male) with a mean (±SD) age of 51.3 ± 15.9 years, median [Q1-Q3] diabetes duration of 30 [16-40] years and mean HbA1c of 60 ± 12 mmol/mol (7.7 ± 1.1%) were included. Sensors were used by 85% of the study population. IAH was present among 78 (16.0%) participants, whereas 86 (17.6%) participants had a history of severe hypoglycaemia. By comparison, the prevalence of IAH equalled 32.5% in 2006, 32.3% in 2010 and 30.1% in 2016 (p for trend <0.001), while the proportion of individuals reporting severe hypoglycaemia equalled 21.2%, 46.7% and 49.8% respectively (p for trend 0.010). Comparing sequential assessments over time, the proportion of individuals with persistent IAH decreased from 74.0% and 63.6% between 2006 and 2016 to 32.5% in 2020.

CONCLUSIONS

Among individuals with type 1 diabetes and high use of sensor technology, the current prevalence of IAH was 16%, about 50% lower as compared to previous years.

Monitoring and treating hypoglycemia during meal-based rapid nutritional rehabilitation in patients with extreme anorexia nervosa

PURPOSE

Hypoglycemia, a complication of prolonged starvation, can be life-threatening and is presumed to contribute to the high mortality of anorexia nervosa. Furthermore, early refeeding in severe anorexia nervosa can precipitate paradoxical post-prandial hypoglycemia. Few studies have analyzed the course of hypoglycemia during nutritional rehabilitation in patients with extremely low-weight anorexia nervosa. No standard practice guidelines exist and recommended strategies for managing hypoglycemia (i.e., nasogastric feeds, high-fat diets) have limitations.

METHODS

This cohort study assessed prevalence and correlates of hypoglycemia in 34 individuals with very low body mass index (BMI < 14.5 kg/m²) anorexia nervosa treated in an intensive eating disorders program with an exclusively meal-based rapid weight gain nutritional protocol. Hypoglycemia was monitored with frequent point of care (POC) glucose testing and treated with oral snacks and continuous slow intravenous 5% dextrose in 0.45% saline (IV D5 1/2 NS) infusion.

RESULTS

POC hypoglycemia was detected in 50% of patients with highest prevalence noted on the day of admission. Hypoglycemia resolved during the first week of hospitalization in most cases and was generally asymptomatic. Seven patients (20.6%) experienced at least one episode of severe hypoglycemia with POC glucose < 50 mg/dl. Lower admission BMI was associated with higher likelihood of developing hypoglycemia and longer duration of hypoglycemia.

CONCLUSION

Meal-based management of hypoglycemia supplemented by continuous IV D5 1/2 NS appears a viable alternative to alternate strategies such as enteral tube feeding. We discuss recommendations for hypoglycemia monitoring during nutritional rehabilitation and directions for future research.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

Evaluation of Clinical Metrics for Identifying Defective Physiologic Responses to Hypoglycemia in Long-Standing Type 1 Diabetes

Repeated hypoglycemia exposure leads to impaired awareness of hypoglycemia (IAH) and the development of defective counterregulatory responses. To date, only pancreas or islet transplantation has demonstrated normalization of hypoglycemia awareness and the endogenous glucose production (EGP) response to defend against insulin-induced hypoglycemia in long-standing type 1 diabetes (T1D). This study aims to validate clinical metrics of IAH (Clarke score), hypoglycemia severity (HYPO score), glycemic lability (lability index), and continuous glucose monitoring (CGM) as predictors of absent autonomic symptom (AS) recognition and defective glucose counterregulation during insulin-induced hypoglycemia, thus enabling early identification of individuals with compromised physiologic defense against clinically significant hypoglycemia. Forty-three subjects with mean ± standard deviation age 43 ± 13 years and T1D duration 28 ± 13 years, including 32 with IAH and 11 with hypoglycemia awareness (Aware), and 12 nondiabetic control subjects, underwent single-blinded randomized-paired hyperinsulinemic-euglycemic and hypoglycemic clamp experiments. Receiver operating characteristic (ROC) curves and sensitivity analyses were performed to assess metric prediction of absent AS recognition and defective EGP responses to hypoglycemia. Clarke score and CGM measures of hypoglycemia exposure demonstrated good ability to predict absent AS recognition (area under the curve ≥0.80). A composite threshold of IAH-Clarke ≥4 with ROC curve-derived thresholds for CGM measures of hypoglycemia exposure showed high specificity and predictive value in identifying an absent AS response during the hypoglycemic clamp. Metrics demonstrated poor ability to predict defective glucose counterregulation by the EGP response, which was impaired even in the Aware group. Screening for IAH alongside assessment of CGM data can increase the specificity for identifying individuals with absent hypoglycemia symptom recognition who may benefit from further intervention.

Altered functional connectivity during hypoglycaemia in type 1 diabetes

Behavioural responses to hypoglycaemia require coordinated recruitment of broadly distributed networks of interacting brain regions. We investigated hypoglycaemia-related changes in brain connectivity in people without diabetes (ND) and with type 1 diabetes with normal (NAH) or impaired (IAH) hypoglycaemia awareness. Two-step hyperinsulinaemic hypoglycaemic clamps were performed in 14 ND, 15 NAH and 22 IAH participants. BOLD timeseries were acquired at euglycaemia (5.0 mmol/L) and hypoglycaemia (2.6 mmol/L), with symptom and counter-regulatory hormone measurements. We investigated hypoglycaemia-related connectivity changes using established seed regions for the default mode (DMN), salience (SN) and central executive (CEN) networks and regions whose activity is modulated by hypoglycaemia: the thalamus and right inferior frontal gyrus (RIFG). Hypoglycaemia-induced changes in the DMN, SN and CEN were evident in NAH (all p < 0.05), with no changes in ND or IAH. However, in IAH there was a reduction in connectivity between regions within the RIFG (p = 0.001), not evident in the ND or NAH groups. We conclude that hypoglycaemia induces coordinated recruitment of the DMN and SN in diabetes with preserved hypoglycaemia awareness which is absent in IAH and ND. Changes in connectivity in the RIFG, a region associated with attentional modulation, may be key in impaired hypoglycaemia awareness.

Symptom Recognition as a Mediator in the Self-Care of Chronic Illness

Background

The recognition of a symptom is needed to initiate a decision to engage in a behavior to ameliorate the symptom. Yet, a surprising number of individuals fail to detect symptoms and delay in addressing early warnings of a health problem.

Purpose

The aim of this study was to test the hypothesis that symptom recognition mediates the relationship between monitoring for and management of symptoms of a chronic illness.

Methods

A secondary analysis of existing cross-sectional data. A sample of 1,629 patients diagnosed with one or more chronic conditions was enrolled in the United States (US) (n = 407), Italy (n = 784) and Sweden (n = 438) between March 2015 and May 2019. Data on self-care monitoring, symptom recognition, and self-care management was assessed using the Self-Care of Chronic Illness Inventory. After confirming metric invariance in cultural assessment, we used structural equation modeling to test a mediation model where symptom recognition was conceptualized as the mediator linking self-care monitoring and self-care management with autonomous (e.g., Change your activity level) and consulting behaviors (e.g., Call your healthcare provider for guidance).

Results

Symptom recognition mediated the relation between self-care monitoring and autonomous self-care management behaviors (β = 0.098, β = 0.122, β = 0.081, p < 0.001 for US, Italy, and Sweden, respectively). No mediation effect was found for consulting self-care management behaviors.

Conclusion

Our findings suggests that symptom recognition promotes autonomous self-care behaviors in people with a chronic condition. Self-care monitoring directly affects consulting self-care management behaviors but not through symptom recognition. Further research is needed to fully understand the role of symptom recognition in the self-care process.

Characteristics of adults with type 1 diabetes and treatment-resistant problematic hypoglycaemia: a baseline analysis from the HARPdoc RCT

AIMS/HYPOTHESIS

Problematic hypoglycaemia still complicates insulin therapy for some with type 1 diabetes. This study describes baseline emotional, cognitive and behavioural characteristics in participants in the HARPdoc trial, which evaluates a novel intervention for treatment-resistant problematic hypoglycaemia.

METHODS

We documented a cross-sectional baseline description of 99 adults with type 1 diabetes and problematic hypoglycaemia despite structured education in flexible insulin therapy. The following measures were included: Hypoglycaemia Fear Survey II (HFS-II); Attitudes to Awareness of Hypoglycaemia questionnaire (A2A); Hospital Anxiety and Depression Index; and Problem Areas In Diabetes. k-mean cluster analysis was applied to HFS-II and A2A factors. Data were compared with a peer group without problematic hypoglycaemia, propensity-matched for age, sex and diabetes duration (n = 81).

RESULTS

The HARPdoc cohort had long-duration diabetes (mean ± SD 35.8 ± 15.4 years), mean ± SD Gold score 5.3 ± 1.2 and a median (IQR) of 5.0 (2.0-12.0) severe hypoglycaemia episodes in the previous year. Most individuals had been offered technology and 49.5% screened positive for anxiety (35.0% for depression and 31.3% for high diabetes distress). The cohort segregated into two clusters: in one (n = 68), people endorsed A2A cognitive barriers to hypoglycaemia avoidance, with low fear on HFS-II factors; in the other (n = 29), A2A factor scores were low and HFS-II high. Anxiety and depression scores were significantly lower in the comparator group.

CONCLUSIONS/INTERPRETATION

The HARPdoc protocol successfully recruited people with treatment-resistant problematic hypoglycaemia. The participants had high anxiety and depression. Most of the cohort endorsed unhelpful health beliefs around hypoglycaemia, with low fear of hypoglycaemia, a combination that may contribute to persistence of problematic hypoglycaemia and may be a target for adjunctive psychological therapies.

Impaired awareness of hypoglycaemia in women with type 1 diabetes in pregnancy: Hypoglycaemia fear, glycaemic and pregnancy outcomes

AIMS

To examine maternal fear of hypoglycaemia, glycaemia and pregnancy outcomes in women with impaired and normal awareness of hypoglycaemia.

METHODS

A pre-planned sub-study of 214 pregnant women with type 1 diabetes who participated in the CONCEPTT trial. Participants completed hypoglycaemia fear surveys (HFS-II) at baseline. Logistic regression and Poisson regression analyses were used to obtain an adjusted estimate for the rate ratio relating awareness to the number of severe hypoglycaemic episodes, and for several neonatal outcomes in relation to the total HFS-II score. The role of continuous glucose monitoring (CGM) use was examined.

RESULTS

Overall, 30% of participants reported impaired awareness of hypoglycaemia (n = 64). Women with impaired awareness of hypoglycaemia had more episodes of severe hypoglycaemia (mean 0.44 vs. 0.08, p < 0.001) (12-34 weeks gestation) and scored higher on the HFS-II scale (43.7 vs. 36.0, p 0.008), indicating more fear of hypoglycaemia. They spent more time below range (CGM <3.5 mmol/L) and exhibited more glycaemic variability at 12 weeks gestation. Higher overall HFS-II scores were associated with a higher risk of maternal severe hypoglycaemia episodes (Rate Ratio 1.78, 95% CI 1.39-2.27). Women with impaired awareness of hypoglycaemia had less maternal weight gain but there were no differences in neonatal outcomes between women with impaired awareness of hypoglycaemia and normal hypoglycaemia awareness. Higher HFS-II scores were associated with more nephropathy (Odds Ratio 1.91, 95% CI 1.06-3.4). CGM use after 12 weeks was not associated with the number of episodes of severe hypoglycaemia (RR 0.75, 95% CI 0.49-1.15; p = 0.18).

CONCLUSIONS

In pregnant women with type 1 diabetes, impaired awareness of hypoglycaemia is associated with more maternal severe hypoglycaemia episodes and more fear of hypoglycaemia. Having impaired awareness of hypoglycaemia and/or fear of hypoglycaemia should alert clinicians to this increased risk. Reassuringly, there was no increase in adverse neonatal outcomes.

A parallel randomised controlled trial of the Hypoglycaemia Awareness Restoration Programme for adults with type 1 diabetes and problematic hypoglycaemia despite optimised self-care (HARPdoc)

Impaired awareness of hypoglycaemia (IAH) is a major risk for severe hypoglycaemia in insulin treatment of type 1 diabetes (T1D). To explore the hypothesis that unhelpful health beliefs create barriers to regaining awareness, we conducted a multi-centre, randomised, parallel, two-arm trial (ClinicalTrials.gov NCT02940873) in adults with T1D and treatment-resistant IAH and severe hypoglycaemia, with blinded analysis of 12-month recall of severe hypoglycaemia at 12 and/or 24 months the primary outcome. Secondary outcomes included cognitive and emotional measures. Adults with T1D, IAH and severe hypoglycaemia despite structured education in insulin adjustment, +/- diabetes technologies, were randomised to the "Hypoglycaemia Awareness Restoration Programme despite optimised self-care" (HARPdoc, n = 49), a psychoeducation programme uniquely focussing on changing cognitive barriers to avoiding hypoglycaemia, or the evidence-based "Blood Glucose Awareness Training" (BGAT, n = 50), both delivered over six weeks. Median [IQR] severe hypoglycaemia at baseline was 5[2-12] per patient/year, 1[0-5] at 12 months and 0[0-2] at 24 months, with no superiority for HARPdoc (HARPdoc vs BGAT incident rate ratios [95% CI] 1.25[0.51, 3.09], p = 0.62 and 1.26[0.48, 3.35], p = 0.64 respectively), nor for changes in hypoglycaemia awareness scores or fear. Compared to BGAT, HARPdoc significantly reduced endorsement of unhelpful cognitions (Estimated Mean Difference for Attitudes to Awareness scores at 24 months, -2.07 [-3.37,-0.560], p = 0.01) and reduced scores for diabetes distress (-6.70[-12.50,-0.89], p = 0.02); depression (-1.86[-3.30, -0.43], p = 0.01) and anxiety (-1.89[-3.32, -0.47], p = 0.01). Despite positive impact on cognitive barriers around hypoglycaemia avoidance and on diabetes-related and general emotional distress scores, HARPdoc was not more effective than BGAT at reducing severe hypoglycaemia.

Enhancing Choices Regarding the Administration of Insulin Among Patients With Diabetes Requiring Insulin Across Countries and Implications for Future Care

There are a number of ongoing developments to improve the care of patients with diabetes across countries given its growing burden. Recent developments include new oral medicines to reduce cardiovascular events and death. They also include new modes to improve insulin administration to enhance adherence and subsequent patient management thereby reducing hypoglycaemia and improving long-term outcomes. In the case of insulins, this includes long-acting insulin analogues as well as continuous glucose monitoring (CGM) systems and continuous subcutaneous insulin infusion systems, combined with sensor-augmented pump therapy and potentially hybrid closed-loops. The benefits of such systems have been endorsed by endocrine societies and governments in patients with Type 1 diabetes whose HbA1c levels are not currently being optimised. However, there are concerns with the low use of such systems across higher-income countries, exacerbated by their higher costs, despite studies suggesting their cost-effectiveness ratios are within accepted limits. This is inconsistent in higher-income countries when compared with reimbursement and funding decisions for new high-priced medicines for cancer and orphan diseases, with often limited benefits, given the burden of multiple daily insulin injections coupled with the need for constant monitoring. This situation is different among patients and governments in low- and low-middle income countries struggling to fund standard insulins and the routine monitoring of HbA1c levels. The first priority in these countries is to address these priority issues before funding more expensive forms of insulin and associated devices. Greater patient involvement in treatment decisions, transparency in decision making, and evidence-based investment decisions should help to address such concerns in the future.

Prevalence of nocturnal hypoglycemia in free-living conditions in adults with type 1 diabetes: What is the impact of daily physical activity?

OBJECTIVE

Studies investigating strategies to limit the risk of nocturnal hypoglycemia associated with physical activity (PA) are scarce and have been conducted in standardized, controlled conditions in people with type 1 diabetes (T1D). This study sought to investigate the effect of daily PA level on nocturnal glucose management in free-living conditions while taking into consideration reported mitigation strategies to limit the risk of nocturnal hyoglycemia in people with T1D.

METHODS

Data from 25 adults (10 males, 15 females, HbA_1c: 7.6 ± 0.8%), 20-60 years old, living with T1D, were collected. One week of continuous glucose monitoring and PA (assessed using an accelerometer) were collected in free-living conditions. Nocturnal glucose values (midnight-6:00 am) following an active day "ACT" and a less active day "L-ACT" were analyzed to assess the time spent within the different glycemic target zones (<3.9 mmol/L; 3.9 - 10.0 mmol/L and >10.0 mmol/L) between conditions. Self-reported data about mitigation strategies applied to reduce the risk of nocturnal hypoglycemia was also analyzed.

RESULTS

Only 44% of participants reported applying a carbohydrate- or insulin-based strategy to limit the risk of nocturnal hypoglycemia on ACT day. Nocturnal hypoglycemia occurrences were comparable on ACT night versus on L-ACT night. Additional post-meal carbohydrate intake was higher on evenings following ACT (27.7 ± 15.6 g, ACT vs. 19.5 ± 11.0 g, L-ACT; P=0.045), but was frequently associated with an insulin bolus (70% of participants). Nocturnal hypoglycemia the night following ACT occurred mostly in people who administrated an additional insulin bolus before midnight (3 out of 5 participants with nocturnal hypoglycemia).

CONCLUSIONS

Although people with T1D seem to be aware of the increased risk of nocturnal hypoglycemia associated with PA, the risk associated with additional insulin boluses may not be as clear. Most participants did not report using compensation strategies to reduce the risk of PA related late-onset hypoglycemia which may be because they did not consider habitual PA as something requiring treatment adjustments.

Prevalence of impaired awareness of hypoglycemia and its risk factors among patients with type 1 diabetes in Saudi Arabia

BACKGROUND AND AIMS

To determine the prevalence of impaired awareness of hypoglycemia (IHA) and self-identification of symptoms in patients with type 1 diabetes (T1D).

METHODS

A cross-sectional study was conducted on 242 patients with T1D at the Diabetes Treatment Center, Prince Sultan Military Medical City (PSMMC), Riyadh, Saudi Arabia from May 2021 to September 2021. In addition to the demographic data, patients' HbA1c level was also collected. Awareness and symptoms of hypoglycemia were assessed using two validated questionnaire-based methods, namely the Gold and Edinburgh methods.

RESULTS

The prevalence of IAH among patients with T1D was 62.8% and the presence of IAH was significantly associated with the duration of T1D (p = 0.019). Compared to males, females had significantly higher (p < 0.05) levels of warmth, pounding heart, and inability to concentrate. Compared to unmarried, married patients had significantly higher levels of (p < 0.05) drowsiness, dizziness, and blurred vision. Similarly, compared to school educated, college-educated showed a higher hunger level (p < 0.05). Patients with HbA1c ≥ 7% possess a significantly higher level of drowsiness, dizziness, and hunger. Dizziness, warmth, difficulty speaking, pounding heart, and blurred vision were significantly higher among patients with diabetes duration ≥10 yrs. Nausea was significantly higher among smokers than non-smokers (p < 0.05).

CONCLUSION

The prevalence of IAH is high among patients with T1D in Saudi Arabia. Focused and evidence-based interventions are essential to minimize the hypoglycemia risk among patients with T1D.

Adherence to antidiabetic treatment and impaired hypoglycemia awareness in type 2 diabetes mellitus assessed in Spanish community pharmacies: the ADHIFAC study

INTRODUCTION

Adherence to treatment and hypoglycemia awareness are strongly linked to glycemic control and hypoglycemia risk in people with type 2 diabetes mellitus (T2DM). Community pharmacies are suitable facilities to detect these conditions, and should be involved in the strategies to minimize the associated risks and burden.

RESEARCH DESIGN AND METHODS

This cross-sectional study conducted at community pharmacies across Spain assessed the prevalence of low adherence to antidiabetic treatments, the frequency of impaired hypoglycemia awareness, and their predictive factors. Adherence was measured with the 8-item Morisky Medication Adherence Scale (MMAS-8) and electronic records of dispensed treatments. The Clarke questionnaire was used to assess impaired hypoglycemia awareness. Healthcare counseling provided in the pharmacy was collected.

RESULTS

Seventy-nine pharmacists and 618 subjects with T2DM participated in the study. Mean age in the overall T2DM population was 67 years, being the majority (69%) pensioners. Adherence was high in 41% of participants, medium in 35%, and low in 24% according to the MMAS-8. Impaired hypoglycemia awareness was observed in 25% of participants. Main determinants of low adherence were the level of education, the number of treatments per patient, hypoglycemia awareness, and the type of pharmacy. Predictive factors of impaired hypoglycemia awareness were the level of education, information on diabetes-related complications, adherence levels, and the type of pharmacy. The proportion of participants who had healthcare counseling was 71% in the overall population and 100% in subjects with impaired hypoglycemia awareness and low adherence. Healthcare counseling comprised diabetes education (69%), pharmacotherapeutic assessment (20%), and physician referrals (11%).

CONCLUSION

Lack of adherence to antidiabetic treatments and impaired hypoglycemia awareness are frequent and correlate in T2DM. Community pharmacies can detect these conditions and should have an active role in the design of strategies to minimize them.

Glucagon as a Therapeutic Approach to Severe Hypoglycemia: After 100 Years, Is It Still the Antidote of Insulin?

Hypoglycemia represents a dark and tormented side of diabetes mellitus therapy. Patients treated with insulin or drug inducing hypoglycemia, consider hypoglycemia as a harmful element, which leads to their resistance and lack of acceptance of the pathology and relative therapies. Severe hypoglycemia, in itself, is a risk for patients and relatives. The possibility to have novel strategies and scientific knowledge concerning hypoglycemia could represent an enormous benefit. Novel available glucagon formulations, even now, allow clinicians to deal with hypoglycemia differently with respect to past years. Novel scientific evidence leads to advances concerning physiopathological mechanisms that regulated glycemic homeostasis. In this review, we will try to show some of the important aspects of this field.

Sleep and hypoglycaemia symptom perception in adults with type-1 diabetes mellitus: A mixed-methods review

AIMS

The study aims to review, synthesize and integrate primary research on the relationship between sleep and hypoglycaemia symptom perception in adults with type-1 diabetes.

DESIGN

This mixed-methods review follows a convergent segregated approach to synthesis and integration of qualitative and quantitative evidence.

DATA SOURCES

With assistance of a biomedical librarian, a search of four databases was conducted (PubMed, CINAHL, Embase and PsycINFO) in June 2020. The review included primary research measuring sleep and hypoglycaemia symptom perception in adults (age ≥ 18 years) with type-1 diabetes in English. Studies that exclusively addressed children, type-2 diabetes or outcomes unrelated to sleep and hypoglycaemia symptom perception were excluded.

REVIEW METHODS

Screening focused on title and abstract review (n = 624). Studies not excluded after screening (n = 35) underwent full-text review. References of each study selected for inclusion (n = 6) were hand searched with one study added. All studies included in the review (n = 7) were critically appraised with JBI Critical Appraisal tools, and then data were extracted with systematic evaluation.

RESULTS

Quantitative synthesis found sleep reduces the magnitude of detectable symptoms and one's capacity to detect them. Qualitative synthesis found that individuals with type-1 diabetes perceive unpredictable severity, frequency and awareness of symptoms while asleep as an oppressive, lingering threat. Integration of findings highlights the troublesome duality of sleep's relationship with hypoglycaemia symptom perception.

CONCLUSIONS

Sleep presents a challenging time for individuals with type-1 diabetes. Further research examining the relationship between sleep and hypoglycaemia symptom perception is recommended as the number of studies limits this review.

IMPACT

Symptom perception is the main physiologic defense against severe hypoglycaemia in type-1 diabetes. This review found that sleep's relationship with hypoglycaemia symptoms has unique physiological and psychological components to address when providing comprehensive care. This review may inform future lines of inquiry that develop into interventions, improvements in practice and risk reduction for hypoglycaemia-related complications.

Structural Gray and White Matter Differences in Patients With Type 1 Diabetes and Impaired Awareness of Hypoglycemia

CONTEXT

Type 1 diabetes (T1D) is associated with an increased risk of cognitive decline, where severe hypoglycemia (SH) and impaired awareness of hypoglycemia (IAH) may play a role. While there is evidence of a possible association between IAH and brain damage, the potential brain changes remain poorly characterized by magnetic resonance imaging (MRI).

OBJECTIVE

To investigate whether there are structural brain differences in a group of T1D patients with IAH compared with normal awareness of hypoglycemia (NAH).

DESIGN

General practice, population-based, cross-sectional study (July 2018 to July 2019).

SETTING

Endocrinology Department, Hospital Santa Creu i Sant Pau.

PARTICIPANTS

A total of 40 T1D patients (20 each with IAH and NAH) matched for age, sex, T1D duration, and education level.

MAIN OUTCOME MEASURES

Using different neuroimaging techniques, we compared whole-brain gray matter (GM) and white matter (WM) differences. We used voxel-based morphometry and cortical surface area analysis methods to assess GM differences, and fractional anisotropy (FA) to assess WM differences.

RESULTS

Compared with patients with T1D-NAH, patients with T1D-IAH had reduced GM volumes and cortical surface areas, especially in frontal and parietal regions (P < 0.05 corrected), and also showed reduced FA values in major WM tracts. The observed MRI differences correlated with both SH frequency and IAH severity.

CONCLUSIONS

MRI for patients with T1D show that IAH is associated with brain changes involving both GM and WM. Further research is needed to elucidate whether the observed differences are a consequence of increased SH episode frequency and increased IAH severity.

Time in range: A best practice guide for UK diabetes healthcare professionals in the context of the COVID-19 global pandemic

The emergence of continuous glucose monitoring has driven improvements in glycaemic control and quality of life for people with diabetes. Recent changes in access to continuous glucose monitoring systems within UK health services have increased the number of people able to benefit from these technologies. The COVID-19 pandemic has created an opportunity for diabetes healthcare professionals to use continuous glucose monitoring technology to remotely deliver diabetes services to support people with diabetes. This opportunity can be maximized with improved application and interpretation of continuous glucose monitoring-generated data. Amongst the diverse measures of glycaemic control, time in range is considered to be of high value in routine clinical care because it is actionable and is visibly responsive to changes in diabetes management. Importantly, it is also been linked to the risk of developing complications associated with diabetes and can be understood by people with diabetes and healthcare professionals alike. The 2019 International Consensus on Time in Range has established a series of target glucose ranges and recommendations for time spent within these ranges that is consistent with optimal glycaemic control. The recommendations cover people with type 1 or type 2 diabetes, with separate targets indicated for elderly people or those at higher risk from hypoglycaemia, as well as for women with type 1 diabetes during pregnancy. The aim of this best practice guide was to clarify the intent and purpose of these international consensus recommendations and to provide practical insights into their implementation in UK diabetes care.

A Comparison of Validated Methods Used to Assess Impaired Awareness of Hypoglycaemia in Type 1 Diabetes: An Observational Study

INTRODUCTION

Clarke, Gold and Pedersen are validated methods to assess awareness of hypoglycaemia. Identifying impaired awareness of hypoglycaemia (IAH) is critical for supporting people with structured education and diabetes technologies, to reduce harm of hypoglycaemia. This study compares the Clarke score, Gold score and Pedersen methods and their correlations with features of hypoglycaemia unawareness and patient characteristics, to evaluate the accuracy of the methods in identifying IAH.

METHODS

This retrospective, observational questionnaire-based study collected routine clinical data from 100 people with type 1 diabetes. The questionnaire included the three validated scoring methods, frequency of severe and nocturnal hypoglycaemia, knowledge and worry of hypoglycaemia and hypoglycaemia symptom scores using the Edinburgh Hypoglycaemia Scale. Data were analysed for IAH prevalence and the associations with features of IAH. The concordance of Clarke, Gold and Pedersen methods was evaluated using Spearman's correlation coefficient.

RESULTS

The prevalence of IAH in this cohort identified by Clarke, Gold and Pedersen methods was 18%, 19% and 61% respectively. The mean autonomic symptom score in people with IAH was significantly reduced using the Clarke method (P = 0.0002) but not on Gold (P = 0.12) and Pedersen methods (P = 0.79). For people with IAH assessed using the Clarke method, scores for night-time worry regarding hypoglycaemia (P = 0.04) and self-reported frequency of nocturnal hypoglycaemia (P = 0.001) were increased. Spearman's correlation coefficients between Pedersen and Clarke and Pedersen and Gold were R_s = 0.555 (P < 0.001) and R_s = 0.645 (P < 0.001) respectively. A moderate association was observed between Clarke and Gold R_s = 0.5669 (P < 0.001).

CONCLUSION

Whilst Clarke and Gold methods determined a similar prevalence of IAH, people identified with IAH assessed by the Clarke method had a significant association with the features and characteristics of IAH, including reduced autonomic symptoms. This study suggests that performing more than one score is important for a reliable risk assessment of IAH.

Clinical approaches to treat impaired awareness of hypoglycaemia

Impaired awareness of hypoglycaemia (IAH) affects between 25% and 30% of all people with type 1 diabetes (T1D) and markedly increases risk of severe hypoglycaemia. This greatly feared complication of T1D impairs quality of life and has a recognised morbidity. People with T1D have an increased propensity to hypoglycaemia as a result of fundamental physiological defects in their ability to respond appropriately to a fall in blood glucose levels. With repeated exposure to low glucose, many then develop a condition referred to as IAH, where there is a reduced ability to perceive the onset of hypoglycaemia and take appropriate corrective action. The management of individuals with IAH relies initially on its identification in the clinic through a detailed exploration of the frequency of hypoglycaemia and an assessment of the individual's ability to recognise these episodes. In this review article, we will address the clinical strategies that may help in the management of the patient with IAH once identified, who may or may not also suffer from problematic hypoglycaemia. The initial focus is on how to identify such patients and then on the variety of approaches involving educational programmes and technological approaches that may be taken to minimise hypoglycaemia risk. No single approach can be advocated for all patients, and it is the role of the health care professional to identify the clinical strategy that best enables their patient to achieve this goal.

Characterizing Glycemic Control and Sleep in Adults with Long-Standing Type 1 Diabetes and Hypoglycemia Unawareness Initiating Hybrid Closed Loop Insulin Delivery

Nocturnal hypoglycemia is life threatening for individuals with type 1 diabetes (T1D) due to loss of hypoglycemia symptom recognition (hypoglycemia unawareness) and impaired glucose counter regulation. These individuals also show disturbed sleep, which may result from glycemic dysregulation. Whether use of a hybrid closed loop (HCL) insulin delivery system with integrated continuous glucose monitoring (CGM) designed for improving glycemic control, relates to better sleep across time in this population remains unknown. The purpose of this study was to describe long-term changes in glycemic control and objective sleep after initiating hybrid closed loop (HCL) insulin delivery in adults with type 1 diabetes and hypoglycemia unawareness. To accomplish this, six adults (median age = 58 y) participated in an 18-month ongoing trial assessing HCL effectiveness. Glycemic control and sleep were measured using continuous glucose monitoring and wrist accelerometers every 3 months. Paired sample t-tests and Cohen's d effect sizes modeled glycemic and sleep changes and the magnitude of these changes from baseline to 9 months. Reduced hypoglycemia (d = 0.47-0.79), reduced basal insulin requirements (d = 0.48), and a smaller glucose coefficient of variation (d = 0.47) occurred with medium-large effect sizes from baseline to 9 months. Hypoglycemia awareness improved from baseline to 6 months with medium-large effect sizes (Clarke score (d = 0.60), lability index (d = 0.50), HYPO score (d = 1.06)). Shorter sleep onset latency (d = 1.53; p < 0.01), shorter sleep duration (d = 0.79), fewer total activity counts (d = 1.32), shorter average awakening length (d = 0.46), and delays in sleep onset (d = 1.06) and sleep midpoint (d = 0.72) occurred with medium-large effect sizes from baseline to 9 months. HCL led to clinically significant reductions in hypoglycemia and improved hypoglycemia awareness. Sleep showed a delayed onset, reduced awakening length and onset latency, and maintenance of high sleep efficiency after initiating HCL. Our findings add to the limited evidence on the relationships between diabetes therapeutic technologies and sleep health. This trial is registered with ClinicalTrials.gov (NCT03215914).

Glucose management for exercise using continuous glucose monitoring (CGM) and intermittently scanned CGM (isCGM) systems in type 1 diabetes: position statement of the European Association for the Study of Diabetes (EASD) and of the International Society for Pediatric and Adolescent Diabetes (ISPAD) endorsed by JDRF and supported by the American Diabetes Association (ADA)

Physical exercise is an important component in the management of type 1 diabetes across the lifespan. Yet, acute exercise increases the risk of dysglycaemia, and the direction of glycaemic excursions depends, to some extent, on the intensity and duration of the type of exercise. Understandably, fear of hypoglycaemia is one of the strongest barriers to incorporating exercise into daily life. Risk of hypoglycaemia during and after exercise can be lowered when insulin-dose adjustments are made and/or additional carbohydrates are consumed. Glycaemic management during exercise has been made easier with continuous glucose monitoring (CGM) and intermittently scanned continuous glucose monitoring (isCGM) systems; however, because of the complexity of CGM and isCGM systems, both individuals with type 1 diabetes and their healthcare professionals may struggle with the interpretation of given information to maximise the technological potential for effective use around exercise (i.e. before, during and after). This position statement highlights the recent advancements in CGM and isCGM technology, with a focus on the evidence base for their efficacy to sense glucose around exercise and adaptations in the use of these emerging tools, and updates the guidance for exercise in adults, children and adolescents with type 1 diabetes. Graphical abstract.

Glucose management for exercise using continuous glucose monitoring (CGM) and intermittently scanned CGM (isCGM) systems in type 1 diabetes: position statement of the European Association for the Study of Diabetes (EASD) and of the International Society for Pediatric and Adolescent Diabetes (ISPAD) endorsed by JDRF and supported by the American Diabetes Association (ADA)

Physical exercise is an important component in the management of type 1 diabetes across the lifespan. Yet, acute exercise increases the risk of dysglycaemia, and the direction of glycaemic excursions depends, to some extent, on the intensity and duration of the type of exercise. Understandably, fear of hypoglycaemia is one of the strongest barriers to incorporating exercise into daily life. Risk of hypoglycaemia during and after exercise can be lowered when insulin-dose adjustments are made and/or additional carbohydrates are consumed. Glycaemic management during exercise has been made easier with continuous glucose monitoring (CGM) and intermittently scanned continuous glucose monitoring (isCGM) systems; however, because of the complexity of CGM and isCGM systems, both individuals with type 1 diabetes and their healthcare professionals may struggle with the interpretation of given information to maximise the technological potential for effective use around exercise (ie, before, during and after). This position statement highlights the recent advancements in CGM and isCGM technology, with a focus on the evidence base for their efficacy to sense glucose around exercise and adaptations in the use of these emerging tools, and updates the guidance for exercise in adults, children and adolescents with type 1 diabetes.

Associations Between the Time in Hypoglycemia and Hypoglycemia Awareness Status in Type 1 Diabetes Patients Using Continuous Glucose Monitoring Systems

Background: Continuous glucose monitoring (CGM) systems help reduce hypoglycemia in patients with type 1 diabetes (T1D). It remains unclear whether T1D patients with impaired awareness of hypoglycemia (IAH) continue to develop more hypoglycemia than those with normal hypoglycemia awareness (NA) despite CGM use. Materials and Methods: For this cross-sectional observational study, 99 T1D patients using real-time CGMs for ≥86% of time were recruited. Fifty and 49 patients were found to have NA and IAH (based on the Clarke questionnaire), respectively. Two-week CGM hypoglycemia data were collected. Results: IAH was associated with greater percentages of CGM values <70 and <54 mg/dL (P = 0.012, P = 0.004) compared to NA. Clarke scores correlated positively with the percentage of CGM values <70 and <54 mg/dL (P = 0.013, P = 0.004). IAH was also related to more events with glucose <70 and <54 mg/dL determined either with at ≥1 time point (P = 0.048, P = 0.003) or lasting ≥20 min (P = 0.016, P = 0.004). IAH patients presented with more day-time events with glucose <54 mg/dL (P = 0.015), nocturnal events with glucose levels <70 and <54 mg/dL (P = 0.009, P = 0.007) and longer day-time event duration with glucose levels <70 and <54 mg/dL (P < 0.001, P = 0.006), respectively. Conclusions: T1D patients with IAH continue to experience more hypoglycemia despite dedicated CGM use.

Hypoglycemia unawareness and autonomic dysfunction in diabetes: Lessons learned and roles of diabetes technologies

Impaired awareness of hypoglycemia (IAH) is a reduction in the ability to recognize low blood glucose levels that would otherwise prompt an appropriate corrective therapy. Identified in approximately 25% of patients with type 1 diabetes, IAH has complex pathophysiology, and might lead to serious and potentially lethal consequences in patients with diabetes, particularly in those with more advanced disease and comorbidities. Continuous glucose monitoring systems can provide real-time glucose information and generate timely alerts on rapidly falling or low blood glucose levels. Given their improvements in accuracy, affordability and integration with insulin pump technology, continuous glucose monitoring systems are emerging as critical tools to help prevent serious hypoglycemia and mitigate its consequences in patients with diabetes. This review discusses the current knowledge on IAH and effective diagnostic methods, the relationship between hypoglycemia and cardiovascular autonomic neuropathy, a practical approach to evaluating cardiovascular autonomic neuropathy for clinicians, and recent evidence from clinical trials assessing the effects of the use of CGM technologies in patients with type 1 diabetes with IAH.

Awareness of hypoglycemia and spectral analysis of heart rate variability in type 1 diabetes

AIMS

To investigate the relationship of unawareness of hypoglycemia with spectral analysis of heart rate variability (HRV) and clinical variables in type 1 diabetes (T1D) individuals.

METHODS

Participants with type 1 diabetes mellitus (type 1 diabetes) were prospectively assessed for hypoglycemia awareness using the Pedersen-Bjergaard method and were classified as normal hypoglycemia awareness, impaired hypoglycemia awareness and hypoglycemia unawareness. Indices of HRV in frequency domain were evaluated and Ewing tests were used for the diagnosis of cardiovascular autonomic neuropathy (CAN).

RESULTS

Ninety-eight participants with T1D (mean age 26 years, average diabetes duration 13 years, and mean HbA1c 8.4%) were included in this study. The prevalence of hypoglycemia unawareness was 28%. No significant difference was observed on the prevalence of CAN among groups of different hypoglycemia awareness (p = 0.740). On regression analyses, abnormal results of HRV in frequency domain were not associated with unawareness of hypoglycemia. On univariable regression analysis, age, diabetes duration and estimated creatinine clearance were associated with unawareness of hypoglycemia.

CONCLUSION

CAN as assessed by Ewing tests and spectral analysis of HRV is not associated with unawareness of hypoglycemia. There is association of age, diabetes duration and renal deficit with unawareness of hypoglycemia.

Differentiating Hypoglycemia Awareness Status from Hypoglycemia Experience in Tools for Measuring Impaired Awareness of Hypoglycemia

Background: Developing technologies in real-time continuous glucose monitoring (CGM) are successfully reducing severe hypoglycemia (SH) in trials and clinical practice. Their impact on impaired awareness of hypoglycemia, a major risk factor for SH, is uncertain. Methods: The present study examined two scales for assessing hypoglycemia awareness status, the Gold score and the eight-item Minimally Modified Clarke Hypoglycemia Survey (MMCHS), commonly used in trials of CGM, in Portuguese-speaking adults with type 1 diabetes and conducted an exploratory factor analysis on MMCHS. Results: A bifactorial structure in MMCHS was revealed, with a clear distinction between items that measure SH experience and those that measure hypoglycemia awareness status. The latter is associated with the same risk for SH as the Gold score. Conclusions: We conclude that improvement in awareness scores by the MMCHS may reflect only a reduction in SH with no restoration of endogenous awareness, making the current literature consistent in evidence that CGM does not improve endogenous awareness and nonsensor supported protection from SH. This has implications for risk of SH when CGM is not being worn.

A randomised controlled study of high intensity exercise as a dishabituating stimulus to improve hypoglycaemia awareness in people with type 1 diabetes: a proof-of-concept study

AIMS/HYPOTHESIS

Approximately 25% of people with type 1 diabetes have suppressed counterregulatory hormonal and symptomatic responses to insulin-induced hypoglycaemia, which renders them at increased risk of severe, disabling hypoglycaemia. This is called impaired awareness of hypoglycaemia (IAH), the cause of which is unknown. We recently proposed that IAH develops through habituation, a form of adaptive memory to preceding hypoglycaemia. Consistent with this hypothesis, we demonstrated restoration of defective counterregulatory hormonal responses to hypoglycaemia (referred to as dishabituation) in a rodent model of IAH following introduction of a novel stress stimulus (high intensity training [HIT]). In this proof-of-concept study we sought to further test this hypothesis by examining whether a single episode of HIT would amplify counterregulatory responses to subsequent hypoglycaemia in people with type 1 diabetes who had IAH (assessed by Gold score ≥4, modified Clarke score ≥4 or Dose Adjustment For Normal Eating (DAFNE) hypoglycaemia awareness rating 2 or 3). The primary outcome was the difference in adrenaline response to hypoglycaemia following both a single episode of HIT and rest.

METHODS

In this randomised, crossover study 12 participants aged between 18 and 55 years with type 1 diabetes for ≥5 years and an HbA_1c <75 mmol/mol (9%) were recruited. Individuals were randomised using computer generated block randomisation to start with one episode of HIT (4 × 30 s cycle sprints [2 min recovery] at 150% of maximum wattage achieved during [Formula: see text] assessment) or rest (control). The following day they underwent a 90 min hyperinsulinaemic-hypoglycaemic clamp study at 2.5 mmol/l with measurement of hormonal counterregulatory response, symptom scores and cognitive testing (four-choice reaction time and digit symbol substitution test). Each intervention and subsequent clamp study was separated by at least 2 weeks. The participants and investigators were not blinded to the intervention or measurements during the study. The investigators were blinded to the primary outcome and blood analysis results.

RESULTS

All participants (six male and six female, age 19-54 years, median [IQR] duration of type 1 diabetes 24.5 [17.3-29.0] years, mean [SEM] HbA_1c 56 [3.67] mmol/mol; 7.3% [0.34%]) completed the study (both interventions and two clamps). In comparison with the rest study, a single episode of HIT led to a 29% increase in the adrenaline (epinephrine) response (mean [SEM]) (2286.5 [343.1] vs 2953.8 [384.9] pmol/l); a significant increase in total symptom scores (Edinburgh Hypoglycaemia Symptom Scale: 24.25 [2.960 vs 27.5 [3.9]; p<0.05), and a significant prolongation of four-choice reaction time (591.8 [22.5] vs 659.9 [39.86] ms; p<0.01] during equivalent hypoglycaemia induced the following day.

CONCLUSIONS/INTERPRETATION

These findings are consistent with the hypothesis that IAH develops in people with type 1 diabetes as a habituated response and that introduction of a novel stressor can restore, at least partially, the adapted counterregulatory hormonal, symptomatic and cognitive responses to hypoglycaemia.

TRIAL REGISTRATION

ISRCTN15236211.

Hypoglycaemia

In health hypoglycaemia is rare and occurs only in circumstances like extreme sports. Hypoglycaemia in type 1 Diabetes (T1D) and advanced type 2 Diabetes (T2D) are the result of interplay between absolute or relative insulin access and defective glucose counterregulation. The basic mechanism is, failure of decreasing insulin and failure of the compensatory increasing counterregulatory hormones at the background of falling blood glucose. Any person with Diabetes on anti-diabetic medication who behaves oddly in any way whatsoever is hypoglycaemic until proven otherwise. Hypoglycaemia can be a terrifying experience for a patient with Diabetes. By definition, hypoglycaemic symptoms are subjective and vary from person to person and even episode to episode in same person. Fear of iatrogenic hypoglycaemia is a major barrier in achieving optimum glycaemic control and quality of life which limits the reduction of diabetic complications. Diabetes patients with comorbidities especially with chronic renal failure, hepatic dysfunction, major limb amputation, terminal illness, cognitive dysfunction etc. are more vulnerable to hypoglycaemia. In most cases, prompt glucose intake reverts hypoglycaemia. Exogenous insulin in T1D and insulin treated advanced T2D have no control by pancreatic regulation. Moreover, failure of increase of glucagon and attenuated secretion in epinephrine causes the defective glucose counterregulation. In this comprehensive review, I will try to touch all related topics for better understanding of hypoglycaemia.

A multiparameter model for non-invasive detection of hypoglycemia

OBJECTIVE

Severe hypoglycemia is the most serious acute complication for people with type 1 diabetes (T1D). Approximately 25% of people with T1D have impaired ability to recognize impending hypoglycemia, and nocturnal episodes are feared.

APPROACH

We have investigated the use of non-invasive sensors for detection of hypoglycemia based on a mathematical model which combines several sensor measurements to identify physiological responses to hypoglycemia. Data from randomized single-blinded euglycemic and hypoglycemic glucose clamps in 20 participants with T1D and impaired awareness of hypoglycemia was used in the analyses.

MAIN RESULTS

Using a sensor combination of sudomotor activity at three skin sites, ECG-derived heart rate and heart rate corrected QT interval, near-infrared and bioimpedance spectroscopy; physiological responses associated with hypoglycemia could be identified with an F1 score accuracy up to 88%.

SIGNIFICANCE

We present a novel model for identification of non-invasively measurable physiological responses related to hypoglycemia, showing potential for detection of moderate hypoglycemia using a wearable sensor system.