Counterregulatory hormone and symptom responses to hypoglycaemia in people with type 1 diabetes, insulin-treated type 2 diabetes or without diabetes: the Hypo-RESOLVE hypoglycaemic clamp study

AIM

The sympathetic nervous and hormonal counterregulatory responses to hypoglycaemia differ between people with type 1 and type 2 diabetes and may change along the course of diabetes, but have not been directly compared. We aimed to compare counterregulatory hormone and symptom responses to hypoglycaemia between people with type 1 diabetes, insulin-treated type 2 diabetes and controls without diabetes, using a standardised hyperinsulinaemic-hypoglycaemic clamp.

MATERIALS

We included 47 people with type 1 diabetes, 15 with insulin-treated type 2 diabetes, and 32 controls without diabetes. Controls were matched according to age and sex to the people with type 1 diabetes or with type 2 diabetes. All participants underwent a hyperinsulinaemic-euglycaemic-(5.2 ± 0.4 mmol/L)-hypoglycaemic-(2.8 ± 0.13 mmol/L)-clamp.

RESULTS

The glucagon response was lower in people with type 1 diabetes (9.4 ± 0.8 pmol/L, 8.0 [7.0-10.0]) compared to type 2 diabetes (23.7 ± 3.7 pmol/L, 18.0 [12.0-28.0], p < 0.001) and controls (30.6 ± 4.7, 25.5 [17.8-35.8] pmol/L, p < 0.001). The adrenaline response was lower in type 1 diabetes (1.7 ± 0.2, 1.6 [1.3-5.2] nmol/L) compared to type 2 diabetes (3.4 ± 0.7, 2.6 [1.3-5.2] nmol/L, p = 0.001) and controls (2.7 ± 0.4, 2.8 [1.4-3.9] nmol/L, p = 0.012). Growth hormone was lower in people with type 2 diabetes than in type 1 diabetes, at baseline (3.4 ± 1.6 vs 7.7 ± 1.3 mU/L, p = 0.042) and during hypoglycaemia (24.7 ± 7.1 vs 62.4 ± 5.8 mU/L, p = 0.001). People with 1 diabetes had lower overall symptom responses than people with type 2 diabetes (45.3 ± 2.7 vs 58.7 ± 6.4, p = 0.018), driven by a lower neuroglycopenic score (27.4 ± 1.8 vs 36.7 ± 4.2, p = 0.012).

CONCLUSION

Acute counterregulatory hormone and symptom responses to experimental hypoglycaemia are lower in people with type 1 diabetes than in those with long-standing insulin-treated type 2 diabetes and controls.

Body Mass Index's influence on arterial hypertension in Type 1 diabetes - A brief report from IMI-SOPHIA study

Information on BMI and risk of developing hypertension in type 1 diabetes (T1D) is scarce, and it comes mostly from cross-sectional analyses. This study underscores a risk of developing hypertension in T1D individuals with high BMI, and this risk appears to be higher than in those with type 2 diabetes.

A Comparison of the Rates of Clock-Based Nocturnal Hypoglycemia and Hypoglycemia While Asleep Among People Living with Diabetes: Findings from the Hypo-METRICS Study

Introduction: Nocturnal hypoglycemia is generally calculated between 00:00 and 06:00. However, those hours may not accurately reflect sleeping patterns and it is unknown whether this leads to bias. We therefore compared hypoglycemia rates while asleep with those of clock-based nocturnal hypoglycemia in adults with type 1 diabetes (T1D) or insulin-treated type 2 diabetes (T2D). Methods: Participants from the Hypo-METRICS study wore a blinded continuous glucose monitor and a Fitbit Charge 4 activity monitor for 10 weeks. They recorded details of episodes of hypoglycemia using a smartphone app. Sensor-detected hypoglycemia (SDH) and person-reported hypoglycemia (PRH) were categorized as nocturnal (00:00-06:00 h) versus diurnal and while asleep versus awake defined by Fitbit sleeping intervals. Paired-sample Wilcoxon tests were used to examine the differences in hypoglycemia rates. Results: A total of 574 participants [47% T1D, 45% women, 89% white, median (interquartile range) age 56 (45-66) years, and hemoglobin A1c 7.3% (6.8-8.0)] were included. Median sleep duration was 6.1 h (5.2-6.8), bedtime and waking time ∼23:30 and 07:30, respectively. There were higher median weekly rates of SDH and PRH while asleep than clock-based nocturnal SDH and PRH among people with T1D, especially for SDH <70 mg/dL (1.7 vs. 1.4, P < 0.001). Higher weekly rates of SDH while asleep than nocturnal SDH were found among people with T2D, especially for SDH <70 mg/dL (0.8 vs. 0.7, P < 0.001). Conclusion: Using 00:00 to 06:00 as a proxy for sleeping hours may underestimate hypoglycemia while asleep. Future hypoglycemia research should consider the use of sleep trackers to record sleep and reflect hypoglycemia while asleep more accurately. The trial registration number is NCT04304963.

Associations Between Hypoglycemia Awareness Status and Symptoms of Hypoglycemia Among Adults with Type 1 or Insulin-Treated Type 2 Diabetes Using the Hypo-METRICS Smartphone Application

Introduction: This study examined associations between hypoglycemia awareness status and hypoglycemia symptoms reported in real-time using the novel Hypoglycaemia-MEasurement, ThResholds and ImpaCtS (Hypo-METRICS) smartphone application (app) among adults with insulin-treated type 1 (T1D) or type 2 diabetes (T2D). Methods: Adults who experienced at least one hypoglycemic episode in the previous 3 months were recruited to the Hypo-METRICS study. They prospectively reported hypoglycemia episodes using the app for 10 weeks. Any of eight hypoglycemia symptoms were considered present if intensity was rated between "A little bit" to "Very much" and absent if rated "Not at all." Associations between hypoglycemia awareness (as defined by Gold score) and hypoglycemia symptoms were modeled using mixed-effects binary logistic regression, adjusting for glucose monitoring method and diabetes duration. Results: Of 531 participants (48% T1D, 52% T2D), 45% were women, 91% white, and 59% used Flash or continuous glucose monitoring. Impaired awareness of hypoglycemia (IAH) was associated with lower odds of reporting autonomic symptoms than normal awareness of hypoglycemia (NAH) (T1D odds ratio [OR] 0.43 [95% confidence interval {CI} 0.25-0.73], P = 0.002); T2D OR 0.51 [95% CI 0.26-0.99], P = 0.048), with no differences in neuroglycopenic symptoms. In T1D, relative to NAH, IAH was associated with higher odds of reporting autonomic symptoms at a glucose concentration <54 than >70 mg/dL (OR 2.18 [95% CI 1.21-3.94], P = 0.010). Conclusion: The Hypo-METRICS app is sensitive to differences in hypoglycemia symptoms according to hypoglycemia awareness in both diabetes types. Given its high ecological validity and low recall bias, the app may be a useful tool in research and clinical settings. The clinical trial registration number is NCT04304963.

Ongoing burden and recent trends in severe hospitalised hypoglycaemia events in people with type 1 and type 2 diabetes in Scotland: A nationwide cohort study 2016-2022

AIMS

We examined severe hospitalised hypoglycaemia (SHH) rates in people with type 1 and type 2 diabetes in Scotland during 2016-2022, stratifying by sociodemographics.

METHODS

Using the Scottish National diabetes register (SCI-Diabetes), we identified people with type 1 and type 2 diabetes alive anytime during 2016-2022. SHH events were determined through linkage to hospital admission and death registry data. We calculated annual SHH rates overall and by age, sex, and socioeconomic status. Summary estimates of time and stratum effects were obtained by fitting adjusted generalised additive models using R package mgcv.

RESULTS

Rates for those under 20 with type 1 diabetes reached their minimum at the 2020-2021 transition, 30% below the study period average. A gradual decline over time also occurred among 20-49-year-olds with type 1 diabetes. Overall, females had 15% higher rates than males with type 2 diabetes (rate ratio 1.15, 95% CI 1.08-1.22). People in the most versus least deprived quintile experienced 2.58 times higher rates (95% CI 2.27-2.93) in type 1 diabetes and 2.33 times higher (95% CI 2.08-2.62) in type 2 diabetes.

CONCLUSIONS

Despite advances in care, SHH remains a significant problem in diabetes. Future efforts must address the large socioeconomic disparities in SHH risks.

The impact of prior exposure to hypoglycaemia on the inflammatory response to a subsequent hypoglycaemic episode

BACKGROUND

Hypoglycaemia has been shown to induce a systemic pro-inflammatory response, which may be driven, in part, by the adrenaline response. Prior exposure to hypoglycaemia attenuates counterregulatory hormone responses to subsequent hypoglycaemia, but whether this effect can be extrapolated to the pro-inflammatory response is unclear. Therefore, we investigated the effect of antecedent hypoglycaemia on inflammatory responses to subsequent hypoglycaemia in humans.

METHODS

Healthy participants (n = 32) were recruited and randomised to two 2-h episodes of either hypoglycaemia or normoglycaemia on day 1, followed by a hyperinsulinaemic hypoglycaemic (2.8 ± 0.1 mmol/L) glucose clamp on day 2. During normoglycaemia and hypoglycaemia, and after 24 h, 72 h and 1 week, blood was drawn to determine circulating immune cell composition, phenotype and function, and 93 circulating inflammatory proteins including hs-CRP.

RESULTS

In the group undergoing antecedent hypoglycaemia, the adrenaline response to next-day hypoglycaemia was lower compared to the control group (1.45 ± 1.24 vs 2.68 ± 1.41 nmol/l). In both groups, day 2 hypoglycaemia increased absolute numbers of circulating immune cells, of which lymphocytes and monocytes remained elevated for the whole week. Also, the proportion of pro-inflammatory CD16+-monocytes increased during hypoglycaemia. After ex vivo stimulation, monocytes released more TNF-α and IL-1β, and less IL-10 in response to hypoglycaemia, whereas levels of 19 circulating inflammatory proteins, including hs-CRP, increased for up to 1 week after the hypoglycaemic event. Most of the inflammatory responses were similar in the two groups, except the persistent pro-inflammatory protein changes were partly blunted in the group exposed to antecedent hypoglycaemia. We did not find a correlation between the adrenaline response and the inflammatory responses during hypoglycaemia.

CONCLUSION

Hypoglycaemia induces an acute and persistent pro-inflammatory response at multiple levels that occurs largely, but not completely, independent of prior exposure to hypoglycaemia. Clinical Trial information Clinicaltrials.gov no. NCT03976271 (registered 5 June 2019).

High intensity interval training as a novel treatment for impaired awareness of hypoglycaemia in people with type 1 diabetes (HIT4HYPOS): a randomised parallel-group study

AIMS/HYPOTHESIS

Impaired awareness of hypoglycaemia (IAH) in type 1 diabetes may develop through a process referred to as habituation. Consistent with this, a single bout of high intensity interval exercise as a novel stress stimulus improves counterregulatory responses (CRR) to next-day hypoglycaemia, referred to as dishabituation. This longitudinal pilot study investigated whether 4 weeks of high intensity interval training (HIIT) has sustained effects on counterregulatory and symptom responses to hypoglycaemia in adults with type 1 diabetes and IAH.

METHODS

HIT4HYPOS was a single-centre, randomised, parallel-group study. Participants were identified using the Scottish Diabetes Research Network (SDRN) and from diabetes outpatient clinics in NHS Tayside, UK. The study took place at the Clinical Research Centre, Ninewells Hospital and Medical School, Dundee, UK. Participants were aged 18-55 years with type 1 diabetes of at least 5 years' duration and HbA1c levels <75 mmol/mol (<9%). They had IAH confirmed by a Gold score ≥4, modified Clarke score ≥4 or Dose Adjustment For Normal Eating [DAFNE] hypoglycaemia awareness rating of 2 or 3, and/or evidence of recurrent hypoglycaemia on flash glucose monitoring. Participants were randomly allocated using a web-based system to either 4 weeks of real-time continuous glucose monitoring (RT-CGM) or RT-CGM+HIIT. Participants and investigators were not masked to group assignment. The HIIT programme was performed for 20 min on a stationary exercise bike three times a week. Hyperinsulinaemic-hypoglycaemic (2.5 mmol/l) clamp studies with assessment of symptoms, hormones and cognitive function were performed at baseline and after 4 weeks of the study intervention. The predefined primary outcome was the difference in hypoglycaemia-induced adrenaline (epinephrine) responses from baseline following RT-CGM or RT-CGM+HIIT.

RESULTS

Eighteen participants (nine men and nine women) with type 1 diabetes (median [IQR] duration 27 [18.75-32] years) and IAH were included, with nine participants randomised to each group. Data from all study participants were included in the analysis. During the 4 week intervention there were no significant mean (SEM) differences between RT-CGM and RT-CGM+HIIT in exposure to level 1 (28 [7] vs 22 [4] episodes, p=0.45) or level 2 (9 [3] vs 4 [1] episodes, p=0.29) hypoglycaemia. The CGM-derived mean glucose level, SD of glucose and glucose management indicator (GMI) did not differ between groups. During the hyperinsulinaemic-hypoglycaemic clamp studies, mean (SEM) change from baseline was greater for the noradrenergic responses (RT-CGM vs RT-CGM+HIIT: -988 [447] vs 514 [732] pmol/l, p=0.02) but not the adrenergic responses (-298 [687] vs 1130 [747] pmol/l, p=0.11) in those participants who had undergone RT-CGM+HIIT. There was a benefit of RT-CGM+HIIT for mean (SEM) change from baseline in the glucagon CRR to hypoglycaemia (RT-CGM vs RT-CGM+HIIT: 1 [4] vs 16 [6] ng/l, p=0.01). Consistent with the hormone response, the mean (SEM) symptomatic response to hypoglycaemia (adjusted for baseline) was greater following RT-CGM+HIIT (RT-CGM vs RT-CGM+HIIT: -4 [2] vs 0 [2], p<0.05).

CONCLUSIONS/INTERPRETATION

In this pilot clinical trial in people with type 1 diabetes and IAH, we found continuing benefits of HIIT for overall hormonal and symptomatic CRR to subsequent hypoglycaemia. Our findings also suggest that HIIT may improve the glucagon response to insulin-induced hypoglycaemia.

TRIAL REGISTRATION

ISRCTN15373978.

FUNDING

Sir George Alberti Fellowship from Diabetes UK (CMF) and the Juvenile Diabetes Research Foundation.

Disrupted hypothalamic transcriptomics and proteomics in a mouse model of type 2 diabetes exposed to recurrent hypoglycaemia

AIMS/HYPOTHESIS

Repeated exposures to insulin-induced hypoglycaemia in people with diabetes progressively impairs the counterregulatory response (CRR) that restores normoglycaemia. This defect is characterised by reduced secretion of glucagon and other counterregulatory hormones. Evidence indicates that glucose-responsive neurons located in the hypothalamus orchestrate the CRR. Here, we aimed to identify the changes in hypothalamic gene and protein expression that underlie impaired CRR in a mouse model of defective CRR.

METHODS

High-fat-diet fed and low-dose streptozocin-treated C57BL/6N mice were exposed to one (acute hypoglycaemia [AH]) or multiple (recurrent hypoglycaemia [RH]) insulin-induced hypoglycaemic episodes and plasma glucagon levels were measured. Single-nuclei RNA-seq (snRNA-seq) data were obtained from the hypothalamus and cortex of mice exposed to AH and RH. Proteomic data were obtained from hypothalamic synaptosomal fractions.

RESULTS

The final insulin injection resulted in similar plasma glucose levels in the RH group and AH groups, but glucagon secretion was significantly lower in the RH group (AH: 94.5±9.2 ng/l [n=33]; RH: 59.0±4.8 ng/l [n=37]; p<0.001). Analysis of snRNA-seq data revealed similar proportions of hypothalamic cell subpopulations in the AH- and RH-exposed mice. Changes in transcriptional profiles were found in all cell types analysed. In neurons from RH-exposed mice, we observed a significant decrease in expression of Avp, Pmch and Pcsk1n, and the most overexpressed gene was Kcnq1ot1, as compared with AH-exposed mice. Gene ontology analysis of differentially expressed genes (DEGs) indicated a coordinated decrease in many oxidative phosphorylation genes and reduced expression of vacuolar H+- and Na+/K+-ATPases; these observations were in large part confirmed in the proteomic analysis of synaptosomal fractions. Compared with AH-exposed mice, oligodendrocytes from RH-exposed mice had major changes in gene expression that suggested reduced myelin formation. In astrocytes from RH-exposed mice, DEGs indicated reduced capacity for neurotransmitters scavenging in tripartite synapses as compared with astrocytes from AH-exposed mice. In addition, in neurons and astrocytes, multiple changes in gene expression suggested increased amyloid beta (Aβ) production and stability. The snRNA-seq analysis of the cortex showed that the adaptation to RH involved different biological processes from those seen in the hypothalamus.

CONCLUSIONS/INTERPRETATION

The present study provides a model of defective counterregulation in a mouse model of type 2 diabetes. It shows that repeated hypoglycaemic episodes induce multiple defects affecting all hypothalamic cell types and their interactions, indicative of impaired neuronal network signalling and dysegulated hypoglycaemia sensing, and displaying features of neurodegenerative diseases. It also shows that repeated hypoglycaemia leads to specific molecular adaptation in the hypothalamus when compared with the cortex.

DATA AVAILABILITY

The transcriptomic dataset is available via the GEO ( http://www.ncbi.nlm.nih.gov/geo/ ), using the accession no. GSE226277. The proteomic dataset is available via the ProteomeXchange data repository ( http://www.proteomexchange.org ), using the accession no. PXD040183.

The Basis for Weekly Insulin Therapy: Evolving Evidence With Insulin Icodec and Insulin Efsitora Alfa

Basal insulin continues to be a vital part of therapy for many people with diabetes. First attempts to prolong the duration of insulin formulations were through the development of suspensions that required homogenization prior to injection. These insulins, which required once- or twice-daily injections, introduced wide variations in insulin exposure contributing to unpredictable effects on glycemia. Advances over the last 2 decades have resulted in long-acting, soluble basal insulin analogues with prolonged and less variable pharmacokinetic exposure, improving their efficacy and safety, notably by reducing nocturnal hypoglycemia. However, adherence and persistence with once-daily basal insulin treatment remains low for many reasons including hypoglycemia concerns and treatment burden. A soluble basal insulin with a longer and flatter exposure profile could reduce pharmacodynamic variability, potentially reducing hypoglycemia, have similar efficacy to once-daily basal insulins, simplify dosing regimens, and improve treatment adherence. Insulin icodec (Novo Nordisk) and insulin efsitora alfa (basal insulin Fc [BIF], Eli Lilly and Company) are 2 such insulins designed for once-weekly administration, which have the potential to provide a further advance in basal insulin replacement. Icodec and efsitora phase 2 clinical trials, as well as data from the phase 3 icodec program indicate that once-weekly insulins provide comparable glycemic control to once-daily analogues, with a similar risk of hypoglycemia. This manuscript details the technology used in the development of once-weekly basal insulins. It highlights the clinical rationale and potential benefits of these weekly insulins while also discussing the limitations and challenges these molecules could pose in clinical practice.

The C5aR1 complement receptor: A novel immunomodulator of insulin action in skeletal muscle

The complement system constitutes an integral component of the innate immune system and plays a critical role in adaptive immunity. Activation of this system engenders the production of complement peptide fragments, including C5a, which engage G-protein coupled receptors predominantly expressed in immune-associated cells, such as neutrophils, initiating pro-inflammatory responses. Intriguingly, our investigation has unveiled the presence of C5a receptor 1 (C5aR1) expression within skeletal muscle, a key metabolic tissue and primary target of insulin. Herein, we demonstrate that C5aR1 activation by C5a in differentiated human skeletal muscle cells elicits acute suppression of insulin signalling. This suppression manifests as impaired insulin-dependent association between IRS1 and the p85 subunit of PI3-kinase, a 50% reduction in Akt phosphorylation, and a 60% decline in insulin-stimulated glucose uptake. This impairment in insulin signalling is associated with a three-fold elevation in intramyocellular diacylglycerol (DAG) levels and a two-fold increase in cytosolic calcium content, which promote PKC-mediated IRS1 inhibition via enhanced phosphorylation at IRS1 Ser1101. Significantly, our findings demonstrate that structurally diverse C5aR1 antagonists, along with genetic deletion or stable silencing of C5aR1 by 80% using short-hairpin RNA, effectively attenuate repression of insulin signalling by C5a in LHCN-M2 human skeletal myotubes. These results underscore the potential of heightened C5aR1 activation, characteristic of obesity and chronic inflammatory conditions, to detrimentally impact insulin function within skeletal muscle cells. Additionally, the study suggests that agents targeting the C5a-C5aR axis, originally devised for mitigating complement-dependent inflammatory conditions, may offer therapeutic avenues to ameliorate immune-driven insulin resistance in key peripheral metabolic tissues, including skeletal muscle.

Metformin increases the uptake of glucose into the gut from the circulation in high-fat diet-fed male mice, which is enhanced by a reduction in whole-body Slc2a2 expression

OBJECTIVES

Metformin is the first line therapy recommended for type 2 diabetes. However, the precise mechanism of action remains unclear and up to a quarter of patients show some degree of intolerance to the drug, with a similar number showing poor response to treatment, limiting its effectiveness. A better understanding of the mechanism of action of metformin may improve its clinical use. SLC2A2 (GLUT2) is a transmembrane facilitated glucose transporter, with important roles in the liver, gut and pancreas. Our group previously identified single nucleotide polymorphisms in the human SLC2A2 gene, which were associated with reduced transporter expression and an improved response to metformin treatment. The aims of this study were to model Slc2a2 deficiency and measure the impact on glucose homoeostasis and metformin response in mice.

METHODS

We performed extensive metabolic phenotyping and 2-deoxy-2-[18F]fluoro-d-glucose ([18F]FDG)-positron emission tomography (PET) analysis of gut glucose uptake in high-fat diet-fed (HFD) mice with whole-body reduced Slc2a2 (Slc2a2+/-) and intestinal Slc2a2 KO, to assess the impact of metformin treatment.

RESULTS

Slc2a2 partial deficiency had no major impact on body weight and insulin sensitivity, however mice with whole-body reduced Slc2a2 expression (Slc2a2+/-) developed an age-related decline in glucose homoeostasis (as measured by glucose tolerance test) compared to wild-type (Slc2a2+/+) littermates. Glucose uptake into the gut from the circulation was enhanced by metformin exposure in Slc2a2+/+ animals fed HFD and this action of the drug was significantly higher in Slc2a2+/- animals. However, there was no effect of specifically knocking-out Slc2a2 in the mouse intestinal epithelial cells.

CONCLUSIONS

Overall, this work identifies a differential metformin response, dependent on expression of the SLC2A2 glucose transporter, and also adds to the growing evidence that metformin efficacy includes modifying glucose transport in the gut. We also describe a novel and important role for this transporter in maintaining efficient glucose homoeostasis during ageing.

Hypoglycaemia induces a sustained pro-inflammatory response in people with type 1 diabetes and healthy controls

AIM

To determine the duration and the extension of the pro-inflammatory response to hypoglycaemia both in people with type 1 diabetes and healthy controls.

MATERIALS AND METHODS

Adults with type 1 diabetes (n = 47) and matched controls (n = 16) underwent a hyperinsulinaemic-euglycaemic hypoglycaemic (2.8 ± 0.1 mmoL/L [49.9 ± 2.3 mg/dL]) glucose clamp. During euglycaemia, hypoglycaemia, and 1, 3 and 7 days later, blood was drawn to determine immune cell phenotype, monocyte function and circulating inflammatory markers.

RESULTS

Hypoglycaemia increased lymphocyte and monocyte counts, which remained elevated for 1 week. The proportion of CD16+ monocytes increased and the proportion of CD14+ monocytes decreased. During hypoglycaemia, monocytes released more tumour necrosis factor-α and interleukin-1β, and less interleukin-10, after ex vivo stimulation. Hypoglycaemia increased the levels of 19 circulating inflammatory proteins, including high sensitive C-reactive protein, most of which remained elevated for 1 week. The epinephrine peak in response to hypoglycaemia was positively correlated with immune cell number and phenotype, but not with the proteomic response.

CONCLUSIONS

Overall, despite differences in prior exposure to hypoglycaemia, the pattern of the inflammatory responses to hypoglycaemia did not differ between people with type 1 diabetes and healthy controls. In conclusion, hypoglycaemia induces a range of pro-inflammatory responses that are sustained for at least 1 week in people with type 1 diabetes and healthy controls.

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.

Assessing the Content Validity, Acceptability, and Feasibility of the Hypo-METRICS App: Survey and Interview Study

BACKGROUND

The Hypoglycaemia - MEasurement, ThResholds and ImpaCtS (Hypo-METRICS) smartphone app was developed to investigate the impact of hypoglycemia on daily functioning in adults with type 1 diabetes mellitus or insulin-treated type 2 diabetes mellitus. The app uses ecological momentary assessments, thereby minimizing recall bias and maximizing ecological validity. It was used in the Hypo-METRICS study, a European multicenter observational study wherein participants wore a blinded continuous glucose monitoring device and completed the app assessments 3 times daily for 70 days.

OBJECTIVE

The 3 aims of the study were to explore the content validity of the app, the acceptability and feasibility of using the app for the duration of the Hypo-METRICS study, and suggestions for future versions of the app.

METHODS

Participants who had completed the 70-day Hypo-METRICS study in the United Kingdom were invited to participate in a brief web-based survey and an interview (approximately 1h) to explore their experiences with the app during the Hypo-METRICS study. Thematic analysis of the qualitative data was conducted using both deductive and inductive methods.

RESULTS

A total of 18 adults with diabetes (type 1 diabetes: n=10, 56%; 5/10, 50% female; mean age 47, SD 16 years; type 2 diabetes: n=8, 44%; 2/8, 25% female; mean age 61, SD 9 years) filled out the survey and were interviewed. In exploring content validity, participants overall described the Hypo-METRICS app as relevant, understandable, and comprehensive. In total, 3 themes were derived: hypoglycemia symptoms and experiences are idiosyncratic; it was easy to select ratings on the app, but day-to-day changes were perceived as minimal; and instructions could be improved. Participants offered suggestions for changes or additional questions and functions that could increase engagement and improve content (such as providing more examples with the questions). In exploring acceptability and feasibility, 5 themes were derived: helping science and people with diabetes; easy to fit in, but more flexibility wanted; hypoglycemia delaying responses and increasing completion time; design, functionality, and customizability of the app; and limited change in awareness of symptoms and impact. Participants described using the app as a positive experience overall and as having a possible, although limited, intervention effect in terms of both hypoglycemia awareness and personal impact.

CONCLUSIONS

The Hypo-METRICS app shows promise as a new research tool to assess the impact of hypoglycemia on an individual's daily functioning. Despite suggested improvements, participants' responses indicated that the app has satisfactory content validity, overall fits in with everyday life, and is suitable for a 10-week research study. Although developed for research purposes, real-time assessments may have clinical value for monitoring and reviewing hypoglycemia symptom awareness and personal impact.

Chronic hyperglycaemia increases the vulnerability of the hippocampus to oxidative damage induced during post-hypoglycaemic hyperglycaemia in a mouse model of chemically induced type 1 diabetes

AIMS/HYPOTHESIS

Chronic hyperglycaemia and recurrent hypoglycaemia are independently associated with accelerated cognitive decline in type 1 diabetes. Recurrent hypoglycaemia in rodent models of chemically induced (streptozotocin [STZ]) diabetes leads to cognitive impairment in memory-related tasks associated with hippocampal oxidative damage. This study examined the hypothesis that post-hypoglycaemic hyperglycaemia in STZ-diabetes exacerbates hippocampal oxidative stress and explored potential contributory mechanisms.

METHODS

The hyperinsulinaemic glucose clamp technique was used to induce equivalent hypoglycaemia and to control post-hypoglycaemic glucose levels in mice with and without STZ-diabetes and Nrf2^-/- mice (lacking Nrf2 [also known as Nfe2l2]). Subsequently, quantitative proteomics based on stable isotope labelling by amino acids in cell culture and biochemical approaches were used to assess oxidative damage and explore contributory pathways.

RESULTS

Evidence of hippocampal oxidative damage was most marked in mice with STZ-diabetes exposed to post-hypoglycaemic hyperglycaemia; these mice also showed induction of Nrf2 and the Nrf2 transcriptional targets Sod2 and Hmox-1. In this group, hypoglycaemia induced a significant upregulation of proteins involved in alternative fuel provision, reductive biosynthesis and degradation of damaged proteins, and a significant downregulation of proteins mediating the stress response. Key differences emerged between mice with and without STZ-diabetes following recovery from hypoglycaemia in proteins mediating the stress response and reductive biosynthesis.

CONCLUSIONS/INTERPRETATION

There is a disruption of the cellular response to a hypoglycaemic challenge in mice with STZ-induced diabetes that is not seen in wild-type non-diabetic animals. The chronic hyperglycaemia of diabetes and post-hypoglycaemic hyperglycaemia act synergistically to induce oxidative stress and damage in the hippocampus, possibly leading to irreversible damage/modification to proteins or synapses between cells. In conclusion, recurrent hypoglycaemia in sub-optimally controlled diabetes may contribute, at least in part, to accelerated cognitive decline through amplifying oxidative damage in key brain regions, such as the hippocampus.

DATA AVAILABILITY

The datasets generated during and/or analysed during the current study are available in ProteomeXchange, accession no. 1-20220824-173727 ( www.proteomexchange.org ). Additional datasets generated during and/or analysed during the present study are available from the corresponding author upon reasonable request.

Cardiovascular Safety in Type 2 Diabetes With Sulfonylureas as Second-Line Drugs: A Nation-Wide Population-Based Comparative Safety Study

OBJECTIVE

To assess the real-world cardiovascular (CV) safety for sulfonylureas (SU), in comparison with dipeptidylpeptidase-4 inhibitors (DPP4i) and thiazolidinediones (TZD), through development of robust methodology for causal inference in a whole nation study.

RESEARCH DESIGN AND METHODS

A cohort study was performed including people with type 2 diabetes diagnosed in Scotland before 31 December 2017, who failed to reach HbA1c 48 mmol/mol despite metformin monotherapy and initiated second-line pharmacotherapy (SU/DPP4i/TZD) on or after 1 January 2010. The primary outcome was composite major adverse cardiovascular events (MACE), including hospitalization for myocardial infarction, ischemic stroke, heart failure, and CV death. Secondary outcomes were each individual end point and all-cause death. Multivariable Cox proportional hazards regression and an instrumental variable (IV) approach were used to control confounding in a similar way to the randomization process in a randomized control trial.

RESULTS

Comparing SU to non-SU (DPP4i/TZD), the hazard ratio (HR) for MACE was 1.00 (95% CI: 0.91-1.09) from the multivariable Cox regression and 1.02 (0.91-1.13) and 1.03 (0.91-1.16) using two different IVs. For all-cause death, the HR from Cox regression and the two IV analyses was 1.03 (0.94-1.13), 1.04 (0.93-1.17), and 1.03 (0.90-1.17).

CONCLUSIONS

Our findings contribute to the understanding that second-line SU for glucose lowering are unlikely to increase CV risk or all-cause mortality. Given their potent efficacy, microvascular benefits, cost effectiveness, and widespread use, this study supports that SU should remain a part of the global diabetes treatment portfolio.

Producing a preference-based quality of LIFE measure to quantify the impact of HYPOGLYCAEMIA on people living with diabetes: A mixed-methods research protocol

BACKGROUND

Assessment of patient-reported outcome measures (PROMs), including quality of life (QoL), is essential in diabetes research and care. However, a recent review concluded that current hypoglycaemia-specific PROMs have limited evidence of validity, reliability and responsiveness for assessing the impact of hypoglycaemia on QoL in people living with diabetes. None of the PROMs identified could be used directly to inform the cost-effectiveness of treatments and interventions. There is a need for a new hypoglycaemia-specific QoL PROM, which can be used directly to inform economic evaluations.

AIMS

This project has three aims: (a) To develop draft PROM content for measuring the impact of hypoglycaemia on QoL in adults with diabetes. (b) To refine the draft content using cognitive debriefing interviews and psychometrics. This will result in a condition-specific PROM that can be used to quantify the impact of hypoglycaemia upon QoL. (c) To generate a preference-based measure (PBM) that will enable utility values to be calculated for economic evaluation.

METHODS

A mixed-methods, three-stage design is used: (a) Qualitative interviews will inform the draft PROM content. (b) Cognitive debriefing interview data will be used to refine the draft PROM content. The PROM will be administered in a large-scale survey to enable psychometric validation. Final item selection for the PROM will be informed by psychometric performance, translatability assessment and input from stakeholder groups. (c) A classification system will be generated, comprising a reduced number of items from the PROM. A valuation survey will be conducted to derive a value set for the PBM.

Findings for iGlarLixi versus BIAsp 30 confirmed in groups of people with type 2 diabetes with different biomedical characteristics

AIM

To report prespecified and post hoc analyses of the SoliMix dataset exploring the impact of baseline participant characteristics on the original SoliMix study outcomes, to enable informed treatment choices for people with different biomedical characteristics.

METHODS

SoliMix (EudraCT 2017-003370-13) compared once-daily iGlarLixi (a fixed-ratio combination of insulin glargine 100 U/mL and the glucagon-like peptide-1 receptor agonist lixisenatide) with twice-daily BIAsp 30 (30% insulin aspart and 70% insulin aspart protamine). In this analysis, the original primary outcomes of noninferiority of iGlarLixi versus BIAsp 30 in terms of glycated haemoglobin (HbA1c) change and superiority in terms of body weight change, together with change in basal insulin dose and hypoglycaemia outcomes, were investigated by baseline age, duration of diabetes, insulin dose, HbA1c level, body mass index (BMI), and renal function.

RESULTS

No evidence of difference in comparative treatment effect was detected across baseline age, duration of diabetes, insulin dose, HbA1c level, BMI and renal function subgroups for any endpoint (all heterogeneity P > 0.05), except American Diabetes Association Level 2 hypoglycaemia event rate when stratified by insulin dose (P = 0.011), which may be a chance difference given multiple testing and the small numbers of Level 2 events.

CONCLUSIONS

Treatment effects of iGlarLixi were consistent irrespective of baseline HbA1c, insulin dose, BMI, age, duration of diabetes and renal function, supporting the use of iGlarLixi as an efficacious and well-tolerated treatment option in people with type 2 diabetes with a wide range of biomedical characteristics.

iGlarLixi versus basal plus Rapid-Acting insulin in adults with type 2 diabetes advancing from basal insulin therapy: The SoliSimplify Real-World study

AIM

For people with suboptimally controlled type 2 diabetes (T2D) on basal insulin (BI), guidelines recommend several treatment advancement options. This study compared the clinical effectiveness of once-daily iGlarLixi versus a multiple-injection BI + rapid acting insulin (RAI) regimen in adults with T2D advancing from BI therapy in real-world clinical practice.

MATERIALS AND METHODS

Electronic medical records from the Observational Medical Outcomes Partnership (OMOP) database were analysed retrospectively using propensity score matching to compare therapy advancement with iGlarLixi or BI + RAI in US adults ≥18 years with T2D on BI who had ≥1 valid glycated haemoglobin (HbA1c) value at baseline and at the 6-month follow-up. The primary objective was non-inferiority of iGlarLixi to BI + RAI in HbA1c change from baseline to 6 months (margin 0.3%).

RESULTS

Propensity score matching generated cohorts with balanced baseline characteristics (N = 814 in each group). HbA1c reduction from baseline to 6 months with iGlarLixi was non-inferior to BI + RAI [mean difference (95% confidence interval): 0.1 (-0.1, 0.2)%; one-sided p = .0032]. At 6 months, weight gain was significantly lower with iGlarLixi than with BI + RAI [-0.8 (-1.3, -0.2) kg; two-sided p = .0069]. Achievement of HbA1c <7% without hypoglycaemia and weight gain were similar between groups [odds ratio (95% confidence interval): 1.15 (0.81, 1.63); p = .4280]. Hypoglycaemia was low in both groups, probably because of underreporting.

CONCLUSIONS

In real-world clinical practice, glycaemic outcomes 6 months after treatment advancement from BI are similar for people with T2D using iGlarLixi versus BI + RAI, with iGlarLixi leading to less weight gain.

Psychometric properties of an innovative smartphone application to investigate the daily impact of hypoglycemia in people with type 1 or type 2 diabetes: The Hypo-METRICS app

INTRODUCTION

The aim of this study was to determine the acceptability and psychometric properties of the Hypo-METRICS (Hypoglycemia MEasurement, ThResholds and ImpaCtS) application (app): a novel tool designed to assess the direct impact of symptomatic and asymptomatic hypoglycemia on daily functioning in people with insulin-treated diabetes.

MATERIALS AND METHODS

100 adults with type 1 diabetes mellitus (T1DM, n = 64) or insulin-treated type 2 diabetes mellitus (T2DM, n = 36) completed three daily 'check-ins' (morning, afternoon and evening) via the Hypo-METRICs app across 10 weeks, to respond to 29 unique questions about their subjective daily functioning. Questions addressed sleep quality, energy level, mood, affect, cognitive functioning, fear of hypoglycemia and hyperglycemia, social functioning, and work/productivity. Completion rates, structural validity, internal consistency, and test-retest reliability were explored. App responses were correlated with validated person-reported outcome measures to investigate convergent (rs>±0.3) and divergent (rs<±0.3) validity.

RESULTS

Participants' mean±SD age was 54±16 years, diabetes duration was 23±13 years, and most recent HbA1c was 56.6±9.8 mmol/mol. Participants submitted mean±SD 191±16 out of 210 possible 'check-ins' (91%). Structural validity was confirmed with multi-level confirmatory factor analysis showing good model fit on the adjusted model (Comparative Fit Index >0.95, Root-Mean-Square Error of Approximation <0.06, Standardized Root-Mean-square Residual<0.08). Scales had satisfactory internal consistency (all ω≥0.5), and high test-retest reliability (rs≥0.7). Convergent and divergent validity were demonstrated for most scales.

CONCLUSION

High completion rates and satisfactory psychometric properties demonstrated that the Hypo-METRICS app is acceptable to adults with T1DM and T2DM, and a reliable and valid tool to explore the daily impact of hypoglycemia.

Improved patient-reported outcomes with iGlarLixi versus premix BIAsp 30 in people with type 2 diabetes in the SoliMix trial

AIM

To assess patient-reported outcomes (PROs) in the SoliMix trial, which compared the efficacy and safety of iGlarLixi versus BIAsp 30 in people with type 2 diabetes (T2D).

MATERIALS AND METHODS

SoliMix (EudraCT: 2017-003370-13), a 26-week, open-label study, randomized (1:1) 887 adults with T2D and HbA1c ≥7.5%-≤10.0% (≥58-≤86 mmol/mol) on basal insulin plus oral antihyperglycaemic drugs (OADs) to once-daily iGlarLixi or twice-daily premix insulin, BIAsp 30. PROs were assessed using the Treatment-Related Impact Measure Diabetes (TRIM-D) and Global Treatment Effectiveness Evaluation (GTEE) questionnaires.

RESULTS

Over 26 weeks, iGlarLixi showed greater improvement from baseline versus BIAsp 30 in total TRIM-D score (least squares mean difference [95% confidence interval]: 5.08 [3.69, 6.47]; effect size: 0.32) and in each TRIM-D domain, with the greatest differences seen in diabetes management (8.47 [6.11, 10.84]) and treatment burden (6.95 [4.83, 9.07]). GTEE scores showed a greater proportion of participants and physicians rated a complete or marked improvement of diabetes control with iGlarLixi (80.5%, 82.8%) versus BIAsp 30 (63.3%, 65.1%) at week 26. Post hoc analyses showed that after adjusting for HbA1c, body weight and hypoglycaemia outcomes, iGlarLixi continued to show greater improvements in TRIM-D total scores versus BIAsp 30.

CONCLUSIONS

In addition to better glycaemic control, weight benefit and less hypoglycaemia, once-daily iGlarLixi provided improved diabetes management, treatment burden and perceived effectiveness versus twice-daily premix BIAsp 30, further supporting iGlarLixi as an advanced treatment option in people with suboptimally controlled T2D on basal insulin plus OADs.

Remembrance of things past: The consequences of recurrent hypoglycaemia in diabetes

AIMS

People with type 1 and type 2 diabetes still frequently experience hypoglycaemia, which can be severe, leading to loss of consciousness. This review will examine the cellular consequences of recurrent hypoglycaemia.

METHODS

This review, based on the Dorothy Hodgkin Lecture given at the Diabetes UK 2022 annual symposium by the author, will discuss our current understanding of the mechanisms by which hypoglycaemia is detected and the consequences of recurrent exposure to hypoglycaemia.

RESULTS

Glucose-responsive cells found in the periphery as well as multiple areas of the brain are organised in a classical sensori-motor integrative network encompassing peripheral, hindbrain and hypothalamic components. The mechanism used by glucose-responsive neurons to detect hypoglycaemia parallel those of the classical glucose sensor the pancreatic ß-cell, namely in their use of glucokinase, K_ATP channels and AMP-activated protein kinase. Recurrent exposure to hypoglycaemia results in a series of cellular adaptations that may be designed to increase the resilience of cells to future hypoglycaemia. This review also highlights how hypoglycaemia, as an oxidative stressor, may also exacerbate chronic hyperglycaemia-induced increases in oxidative stress and inflammation, leading to damage to vulnerable brain regions.

CONCLUSIONS

Impaired awareness of hypoglycaemia follows the adaptation of central glucose-responsive neurons to repeated hypoglycaemia and may represent a form of memory called habituation. In diabetes, recurrent hypoglycaemia may have tissue consequences as a result of a profound disruption in the cellular response to a hypoglycaemic challenge that increases vulnerability to oxidative damage.

Sustained Proinflammatory Effects of Hypoglycemia in People With Type 2 Diabetes and in People Without Diabetes

Iatrogenic hypoglycemia activates the immune system and is associated with an increased risk for atherosclerotic disease. We determined acute and long-term effects of insulin-induced hypoglycemia on inflammatory markers in humans with or without type 2 diabetes. A total of 15 adults with type 2 diabetes and 16 matched control subjects (17 men and 14 women, age 59.6 ± 7.1 years, BMI 28.5 ± 4.3 kg/m2) underwent a hyperinsulinemic-euglycemic (5.31 ± 0.32 mmol/L) hypoglycemic (2.80 ± 0.12 mmol/L) glucose clamp. Blood was drawn during euglycemia and hypoglycemia and 1, 3, and 7 days later to determine circulating immune cell composition, function, and inflammatory proteins. In response to hypoglycemia, absolute numbers of circulating lymphocytes and monocytes significantly increased and remained elevated for 1 week. The proportion of CD16+ monocytes increased, and the proportion of CD14+ monocytes decreased, which was sustained for 1 week in people without diabetes. During hypoglycemia, ex vivo stimulated monocytes released more tumor necrosis factor-α and interleukin 1β, and less interleukin 10, particularly in people with diabetes. hs-CRP and 25 circulating inflammatory proteins increased, remaining significantly elevated 1 week after hypoglycemia. While levels at euglycemia differed, responses to hypoglycemia were broadly similar in people with or without type 2 diabetes. We conclude that hypoglycemia induces a proinflammatory response at the cellular and protein level that is sustained for 1 week in people with type 2 diabetes and control subjects.

Hypoglycaemia events with iGlarLixi versus premix biphasic insulin aspart 30 (BIAsp 30) in people with type 2 diabetes advancing from basal insulin: An analysis of the SoliMix trial

AIMS

To explore details of the incidence and rates of daytime and nocturnal hypoglycaemia, levels of hypoglycaemia, and relationship to glycated haemoglobin (HbA1c), when comparing iGlarLixi versus premixed biphasic insulin aspart 30 (BIAsp 30) in the SoliMix randomized controlled trial.

MATERIALS AND METHODS

This exploratory analysis of SoliMix used logistic regression and negative binomial regression analyses to assess between-treatment differences in the incidence and rates of hypoglycaemia by time of day. A negative binomial model was used to derive estimated annualized hypoglycaemia rates as a function of HbA1c.

RESULTS

iGlarLixi was associated with lower incidence and rates of American Diabetes Association Level 2 (<54 mg/dL [<3.0 mmol/L]) hypoglycaemia during both night and day versus BIAsp 30. Incidence and rates of Level 1 (<70 to ≥54 mg/dL [<3.9 to ≥3.0 mmol/L]) hypoglycaemia were also mostly shown to be reduced with iGlarLixi versus BIAsp 30. Severe (Level 3) events were too few for analysis (n = 3). iGlarLixi was associated with lower modelled event rates of Level 2 and Level 1 hypoglycaemia over a wide range of HbA1c levels versus BIAsp 30.

CONCLUSIONS

These results show that the lower HbA1c levels and weight benefit seen with iGlarLixi versus premixed BIAsp 30 in people with type 2 diabetes advancing their basal insulin therapy in the SoliMix trial are also accompanied by a lower risk of hypoglycaemia at any time of day and across a broad range of HbA1c levels.

Glycaemic thresholds for counterregulatory hormone and symptom responses to hypoglycaemia in people with and without type 1 diabetes: a systematic review

AIM/HYPOTHESIS

The physiological counterregulatory response to hypoglycaemia is reported to be organised hierarchically, with hormone responses usually preceding symptomatic awareness and autonomic responses preceding neuroglycopenic responses. To compare thresholds for activation of these responses more accurately between people with or without type 1 diabetes, we performed a systematic review on stepped hyperinsulinaemic-hypoglycaemic glucose clamps.

METHODS

A literature search in PubMed and EMBASE was conducted. We included articles published between 1980 and 2018 involving hyperinsulinaemic stepped hypoglycaemic glucose clamps among people with or without type 1 diabetes. Key exclusion criteria were as follows: data were previously published; other patient population; a clamp not the primary intervention; and an inadequate clamp description. Glycaemic thresholds for counterregulatory hormone and/or symptom responses to hypoglycaemia were estimated and compared using generalised logrank test for interval-censored data, where the intervals were either extracted directly or calculated from the data provided by the study. A glycaemic threshold was defined as the glucose level at which the response exceeded the 95% CI of the mean baseline measurement or euglycaemic control clamp. Because of the use of interval-censored data, we described thresholds using median and IQR.

RESULTS

A total of 63 articles were included, whereof 37 papers included participants with type 1 diabetes (n=559; 67.4% male sex, aged 32.7±10.2 years, BMI 23.8±1.4 kg/m²) and 51 papers included participants without diabetes (n=733; 72.4% male sex, aged 31.1±9.2 years, BMI 23.6±1.1 kg/m²). Compared with non-diabetic control individuals, in people with type 1 diabetes, the median (IQR) glycaemic thresholds for adrenaline (3.8 [3.2-4.2] vs 3.4 [2.8-3.9 mmol/l]), noradrenaline (3.2 [3.2-3.7] vs 3.0 [2.8-3.1] mmol/l), cortisol (3.5 [3.2-4.2]) vs 2.8 [2.8-3.4] mmol/l) and growth hormone (3.8 [3.3-3.8] vs. 3.2 [3.0-3.3] mmol/l) all occurred at lower glucose levels in people with diabetes than in those without diabetes (all p≤0.01). Similarly, although both autonomic (median [IQR] 3.4 [3.4-3.4] vs 3.0 [2.8-3.4] mmol/l) and neuroglycopenic (median [IQR] 3.4 [2.8-N/A] vs 3.0 [3.0-3.1] mmol/l) symptom responses were elicited at lower glucose levels in people with type 1 diabetes, the thresholds for autonomic and neuroglycopenic symptoms did not differ for each individual subgroup.

CONCLUSIONS/INTERPRETATION

People with type 1 diabetes have glycaemic thresholds for counterregulatory hormone and symptom responses at lower glucose levels than people without diabetes. Autonomic and neuroglycopenic symptoms responses are generated at about similar levels of hypoglycaemia. There was a considerable variation in the methodology of the articles and the high insulin doses in most of the clamps may affect the counterregulatory responses.

FUNDING

This article has received funding from the Innovative Medicines Initiative 2 Joint Undertaking (JU) under grant agreement no. 777460.

REGISTRATION

This systematic review is registered in PROSPERO (CRD42019120083).

Hypo-METRICS: Hypoglycaemia-MEasurement, ThResholds and ImpaCtS-A multi-country clinical study to define the optimal threshold and duration of sensor-detected hypoglycaemia that impact the experience of hypoglycaemia, quality of life and health economic outcomes: The study protocol

INTRODUCTION

Hypoglycaemia is a significant burden to people living with diabetes and an impediment to achieving optimal glycaemic outcomes. The use of continuous glucose monitoring (CGM) has improved the capacity to assess duration and level of hypoglycaemia. The personal impact of sensor-detected hypoglycaemia (SDH) is unclear. Hypo-METRICS is an observational study designed to define the threshold and duration of sensor glucose that provides the optimal sensitivity and specificity for events that people living with diabetes experience as hypoglycaemia.

METHODS

We will recruit 600 participants: 350 with insulin-treated type 2 diabetes, 200 with type 1 diabetes and awareness of hypoglycaemia and 50 with type 1 diabetes and impaired awareness of hypoglycaemia who have recent experience of hypoglycaemia. Participants will wear a blinded CGM device and an actigraphy monitor to differentiate awake and sleep times for 10 weeks. Participants will be asked to complete three short surveys each day using a bespoke mobile phone app, a technique known as ecological momentary assessment. Participants will also record all episodes of self-detected hypoglycaemia on the mobile app. We will use particle Markov chain Monte Carlo optimization to identify the optimal threshold and duration of SDH that have optimum sensitivity and specificity for detecting patient-reported hypoglycaemia. Key secondary objectives include measuring the impact of symptomatic and asymptomatic SDH on daily functioning and health economic outcomes.

ETHICS AND DISSEMINATION

The protocol was approved by local ethical boards in all participating centres. Study results will be shared with participants, in peer-reviewed journal publications and conference presentations.

Consistent Effects of Hypoglycemia on Cognitive Function in People With or Without Diabetes

OBJECTIVE

Hypoglycemia poses an immediate threat for cognitive function. Due to its association with acute cognitive impairment, the International Hypoglycemia Study Group (IHSG) defines a blood glucose level <3.0 mmol/L as "level 2 hypoglycemia." In the current study we investigated whether having diabetes, type of diabetes, or hypoglycemia awareness moderates this association.

RESEARCH DESIGN AND METHODS

Adults with type 1 diabetes with normal (n = 26) or impaired (n = 21) hypoglycemic awareness or with insulin-treated type 2 diabetes (n = 15) and age-matched control subjects without diabetes (n = 32) underwent a hyperinsulinemic-euglycemic-hypoglycemic glucose clamp (2.80 ± 0.13 mmol/L [50.2 ± 2.3 mg/dL]). At baseline and during hypoglycemia, calculation ability, attention, working memory and cognitive flexibility were measured with the Paced Auditory Serial Addition Test (PASAT) and the Test of Attentional Performance (TAP).

RESULTS

For the whole group, hypoglycemia decreased the mean ± SD proportion of correct answers on the PASAT by 8.4 ± 12.8%, increased reaction time on the TAP Alertness task by 32.1 ± 66.6 ms, and increased the sum of errors and omissions on the TAP Working Memory task by 2.0 ± 5.5 (all P < 0.001). Hypoglycemia-induced cognitive declines were largely irrespective of the presence or type of diabetes, level of symptomatic awareness, diabetes duration, or HbA1c.

CONCLUSIONS

IHSG level 2 hypoglycemia impairs cognitive function in people with and without diabetes, irrespective of type of diabetes or hypoglycemia awareness status. These findings support the cutoff value of hypoglycemia <3.0 mmol/L (<54 mg/dL) as being clinically relevant for most people with diabetes.

The 12-Item Hypoglycemia Impact Profile (HIP12): psychometric validation of a brief measure of the impact of hypoglycemia on quality of life among adults with type 1 or type 2 diabetes

INTRODUCTION

The aim of this study was to determine the psychometric properties of the 12-Item Hypoglycemia Impact Profile (HIP12), a brief measure of the impact of hypoglycemia on quality of life (QoL) among adults with type 1 (T1D) or type 2 diabetes (T2D).

RESEARCH DESIGN AND METHODS

Adults with T1D (n=1071) or T2D (n=194) participating in the multicountry, online study, 'Your SAY: Hypoglycemia', completed the HIP12. Psychometric analyses were undertaken to determine acceptability, structural validity, internal consistency, convergent/divergent validity, and known-groups validity.

RESULTS

Most (98%) participants completed all items on the HIP12. The expected one-factor solution was supported for T1D, T2D, native English speaker, and non-native English speaker groups. Internal consistency was high across all groups (ω=0.91-0.93). Convergent and divergent validity were satisfactory. Known-groups validity was demonstrated for both diabetes types, by frequency of severe hypoglycemia (0 vs ≥1 episode in the past 12 months) and self-treated episodes (<2 vs 2-4 vs ≥5 per week). The measure also discriminated by awareness of hypoglycemia in those with T1D.

CONCLUSIONS

The HIP12 is an acceptable, internally consistent, and valid tool for assessing the impact of hypoglycemia on QoL among adults with T1D. The findings in the relatively small sample with T2D are encouraging and warrant replication in a larger sample.

Efficacy and safety of cotadutide, a dual glucagon-like peptide-1 and glucagon receptor agonist, in a randomized phase 2a study of patients with type 2 diabetes and chronic kidney disease

AIM

To assess the efficacy, safety and tolerability of cotadutide in patients with type 2 diabetes mellitus and chronic kidney disease.

MATERIALS AND METHODS

In this phase 2a study (NCT03550378), patients with body mass index 25-45 kg/m² , estimated glomerular filtration rate 30-59 ml/min/1.73 m² and type 2 diabetes [glycated haemoglobin 6.5-10.5% (48-91 mmol/mol)] controlled with insulin and/or oral therapy combination, were randomized 1:1 to once-daily subcutaneous cotadutide (50-300 μg) or placebo for 32 days. The primary endpoint was plasma glucose concentration assessed using a mixed-meal tolerance test.

RESULTS

Participants receiving cotadutide (n = 21) had significant reductions in the mixed-meal tolerance test area under the glucose concentration-time curve (-26.71% vs. +3.68%, p < .001), more time in target glucose range on continuous glucose monitoring (+14.79% vs. -21.23%, p = .001) and significant reductions in absolute bodyweight (-3.41 kg vs. -0.13 kg, p < .001) versus placebo (n = 20). In patients with baseline micro- or macroalbuminuria (n = 18), urinary albumin-to-creatinine ratios decreased by 51% at day 32 with cotadutide versus placebo (p = .0504). No statistically significant difference was observed in mean change in estimated glomerular filtration rate between treatments. Mild/moderate adverse events occurred in 71.4% of participants receiving cotadutide and 35.0% receiving placebo.

CONCLUSIONS

We established the efficacy of cotadutide in this patient population, with significantly improved postprandial glucose control and reduced bodyweight versus placebo. Reductions in urinary albumin-to-creatinine ratios suggest potential benefits of cotadutide on kidney function, supporting further evaluation in larger, longer-term clinical trials.

Cost-Effectiveness of iGlarLixi Versus Premix BIAsp 30 in Patients with Type 2 Diabetes Suboptimally Controlled by Basal Insulin in the UK

INTRODUCTION

iGlarLixi is indicated as an adjunct to diet and exercise in addition to metformin (with or without sodium-glucose cotransporter-2 inhibitors) to improve glycemic control in adults with insufficiently controlled type 2 diabetes (T2D). A cost-effectiveness analysis was conducted to compare iGlarLixi with premix biphasic insulin aspart 30 (BIAsp 30) in people with T2D suboptimally controlled with basal insulin (BI).

METHODS

The IQVIA CORE Diabetes Model was used to estimate lifetime costs and outcomes for people with T2D from a UK health care perspective at a willingness-to-pay threshold of £20,000. Initial clinical data were based on the phase 3 randomized, open-label, active-controlled SoliMix clinical trial which compared the efficacy and safety of once-daily iGlarLixi with that of twice-daily BIAsp 30. Costs associated with management and complications and utilities values were derived from published sources. Lifetime costs (in £GBP) and quality-adjusted life-years (QALYs) were predicted; extensive scenario and sensitivity analyses were conducted.

RESULTS

Estimated QALYs gained were slightly higher with iGlarLixi (8.9 vs. 8.8) compared with premix BIAsp 30, at a higher cost (£23,204 vs. £21,961). The base case incremental cost-effectiveness ratio (ICER) per QALY was £13,598. Treatment acquisition was the main driver of cost differences (iGlarLixi, £11,750; premix BIAsp 30, £10,395). Costs associated with management and complications were generally similar between comparators.

CONCLUSION

iGlarLixi provides improved QALY outcomes at an acceptable cost compared with premix BIAsp 30, with an ICER below the threshold generally considered acceptable by UK authorities. In people with T2D, iGlarLixi is a simple, cost-effective option for advancing therapy of BI, with fewer daily injections than premix BIAsp 30.

Investigating the day-to-day impact of hypoglycaemia in adults with type 1 or type 2 diabetes: design and validation protocol of the Hypo-METRICS application

INTRODUCTION

Hypoglycaemia is a frequent adverse event and major barrier for achieving optimal blood glucose levels in people with type 1 or type 2 diabetes using insulin. The Hypo-RESOLVE (Hypoglycaemia-Redefining SOLutions for better liVEs) consortium aims to further our understanding of the day-to-day impact of hypoglycaemia. The Hypo-METRICS (Hypoglycaemia-MEasurement, ThResholds and ImpaCtS) application (app) is a novel app for smartphones. This app is developed as part of the Hypo-RESOLVE project, using ecological momentary assessment methods that will minimise recall bias and allow for robust investigation of the day-to-day impact of hypoglycaemia. In this paper, the development and planned psychometric analyses of the app are described.

METHODS AND ANALYSIS

The three phases of development of the Hypo-METRICS app are: (1) establish a working group-comprising diabetologists, psychologists and people with diabetes-to define the problem and identify relevant areas of daily functioning; (2) develop app items, with user-testing, and implement into the app platform; and (3) plan a large-scale, multicountry study including interviews with users and psychometric validation. The app includes 7 modules (29 unique items) assessing: self-report of hypoglycaemic episodes (during the day and night, respectively), sleep quality, well-being/cognitive function, social interactions, fear of hypoglycaemia/hyperglycaemia and work/productivity. The app is designed for use within three fixed time intervals per day (morning, afternoon and evening). The first version was released mid-2020 for use (in conjunction with continuous glucose monitoring and activity tracking) in the Hypo-METRICS study; an international observational longitudinal study. As part of this study, semistructured user-experience interviews and psychometric analyses will be conducted.

ETHICS AND DISSEMINATION

Use of the novel Hypo-METRICS app in a multicountry clinical study has received ethical approval in each of the five countries involved (Oxford B Research Ethics Committee, CMO Region Arnhem-Nijmegen, Ethikkommission der Medizinischen Universität Graz, Videnskabsetisk Komite for Region Hovedstaden and the Comite Die Protection Des Personnes SUD Mediterranne IV). The results from the study will be published in peer review journals and presented at national and international conferences.

TRIAL REGISTRATION NUMBER

NCT04304963.

Flash monitor initiation is associated with improvements in HbA1c levels and DKA rates among people with type 1 diabetes in Scotland: a retrospective nationwide observational study

AIMS/HYPOTHESIS

We assessed the real-world effect of flash monitor (FM) usage on HbA_1c levels and diabetic ketoacidosis (DKA) and severe hospitalised hypoglycaemia (SHH) rates among people with type 1 diabetes in Scotland and across sociodemographic strata within this population.

METHODS

This study was retrospective, observational and registry based. Using the national diabetes registry, 14,682 individuals using an FM at any point between 2014 and mid-2020 were identified. Within-person change from baseline in HbA_1c following FM initiation was modelled using linear mixed models accounting for within-person pre-exposure trajectory. DKA and SHH events were captured through linkage to hospital admission and mortality data. The difference in DKA and SHH rates between FM-exposed and -unexposed person-time was assessed among users, using generalised linear mixed models with a Poisson likelihood. In a sensitivity analysis, we tested whether changes in these outcomes were seen in an age-, sex- and baseline HbA_1c-matched sample of non-users over the same time period.

RESULTS

Prevalence of ever-FM use was 45.9% by mid-2020, with large variations by age and socioeconomic status: 64.3% among children aged <13 years vs 32.7% among those aged ≥65 years; and 54.4% vs 36.2% in the least-deprived vs most-deprived quintile. Overall, the median (IQR) within-person change in HbA_1c in the year following FM initiation was -2.5 (-9.0, 2.5) mmol/mol (-0.2 [-0.8, 0.2]%). The change varied widely by pre-usage HbA_1c: -15.5 (-31.0, -4.0) mmol/mol (-1.4 [-2.8, -0.4]%) in those with HbA_1c > 84 mmol/mol [9.8%] and 1.0 (-2.0, 5.5) mmol/mol (0.1 [-0.2, 0.5]%) in those with HbA_1c < 54 mmol/mol (7.1%); the corresponding estimated fold change (95% CI) was 0.77 (0.76, 0.78) and 1.08 (1.07, 1.09). Significant reductions in HbA_1c were found in all age bands, sexes and socioeconomic strata, and regardless of prior/current pump use, completion of a diabetes education programme or early FM adoption. Variation between the strata of these factors beyond that driven by differing HbA_1c at baseline was slight. No change in HbA_1c in matched non-users was observed in the same time period (median [IQR] within-person change = 0.5 [-5.0, 5.5] mmol/mol [0.0 (-0.5, 0.5)%]). DKA rates decreased after FM initiation overall and in all strata apart from the adolescents. Estimated overall reduction in DKA event rates (rate ratio) was 0.59 [95% credible interval (CrI) 0.53, 0.64]) after FM vs before FM initiation, accounting for pre-exposure trend. Finally, among those at higher risk for SHH, estimated reduction in event rates was rate ratio 0.25 (95%CrI 0.20, 0.32) after FM vs before FM initiation.

CONCLUSIONS/INTERPRETATION

FM initiation is associated with clinically important reductions in HbA_1c and striking reduction in DKA rate. Increasing uptake among the socioeconomically disadvantaged offers considerable potential for tightening the current socioeconomic disparities in glycaemia-related outcomes.

Foot Ulcer and Risk of Lower Limb Amputation or Death in People With Diabetes: A National Population-Based Retrospective Cohort Study

OBJECTIVE

To describe incidence of foot ulceration and amputation-free survival associated with foot ulceration status in a national population-based cohort study of people with diabetes.

RESEARCH DESIGN AND METHODS

The study population included 233,459 people with diabetes who were alive in Scotland on 1 January 2012 identified from the national population-based register (national prevalence 4.9%). Characteristics of patients identified from linked hospital and mortality records during follow-up to the end of November 2017 were compared by outcome. Cox regression was used to assess the association between history of foot ulcer and amputation-free survival.

RESULTS

The population included 23,395 people with type 1 diabetes and 210,064 people with type 2 diabetes. In total there were 13,093 (5.6%) people who had a previous foot ulceration, 9,023 people who developed a first ulcer, 48,995 who died, and 2,866 who underwent minor or major amputation during follow-up. Overall incidence of first-time foot ulcers was 7.8 per 1,000 person-years (95% CI7.6-7.9) and 11.2 (11.0-11.4) for any ulcer. Risk factors for reduced amputation-free survival included social deprivation, mental illness, and being underweight in addition to conventional cardiovascular risk factors. Adjusted hazard ratios (95% CI) were 2.09 (1.89-2.31) for type 1 diabetes and 1.65 (1.60-1.70) for type 2 diabetes.

CONCLUSIONS

The overall incidence of foot ulceration in a population-based study of people with diabetes was 11.2 per 1,000 person-years. Foot ulceration is associated with lower amputation-free survival rate, a potential measure of effectiveness of care among people with diabetes. Mental illness and social deprivation are also highlighted as risk factors.

Cost-Effectiveness of iGlarLixi in People with Type 2 Diabetes Mellitus Suboptimally Controlled on Basal Insulin Plus Metformin in the UK

INTRODUCTION

A cost-effectiveness analysis was conducted comparing a fixed-ratio combination (FRC) of insulin glargine 100 units/mL plus lixisenatide (iGlarLixi) versus the FRC of insulin degludec plus liraglutide (iDegLira) and the free-combination comparators insulin glargine plus dulaglutide (iGlar plus Dula) and basal insulin plus liraglutide (BI plus Lira).

METHODS

The IQVIA Core Diabetes Model was used to estimate lifetime costs and outcomes for a cohort of patients with type 2 diabetes mellitus (T2DM) from the UK healthcare perspective. Initial clinical data for iGlarLixi were based on the randomized, controlled LixiLan-L trial and the relative treatment effects for comparators were based on an indirect treatment comparison using data from the AWARD-9 (iGlar plus Dula), LIRA ADD2 BASAL (BI plus Lira), and DUAL V (iDegLira) trials. Costs were derived from publicly available sources. Lifetime costs (in British Pound Sterling [£]) and quality-adjusted life-years (QALYs) were predicted; net monetary benefit (NMB) for iGlarLixi versus comparators was derived using a willingness-to-pay threshold of £20,000. Extensive scenario and sensitivity analyses were conducted.

RESULTS

Estimated costs were lowest with iGlarLixi (£31,295) compared with iGlar plus Dula (£38,790), iDegLira (£40,179), and BI plus Lira (£42,467). Total QALYs gained were identical with iGlarLixi and iDegLira (8.438), and comparable with iGlar plus Dula (8.439) and BI plus Lira (8.466). NMB for iGlarLixi was positive versus all comparators (£10,603.86 vs. BI plus Lira; £7,466.24 vs. iGlar plus Dula; £8.874.11 vs. iDegLira).

CONCLUSION

In patients with T2DM with suboptimal glycemic control on basal insulin, iGlarLixi provides very similar outcomes and substantial cost savings, compared with other fixed and free combinations of insulins plus glucagon-like peptide-1 receptor agonists.

Cost-Effectiveness of iGlarLixi Versus iDegLira in Type 2 Diabetes Mellitus Inadequately Controlled by GLP-1 Receptor Agonists and Oral Antihyperglycemic Therapy

INTRODUCTION

The fixed-ratio combinations (FRCs) of glucagon-like peptide 1 receptor agonists (GLP-1 RAs) and basal insulin, insulin glargine 100 U/mL plus lixisenatide (iGlarLixi), and insulin degludec plus liraglutide (iDegLira), have demonstrated safety and efficacy in patients with type 2 diabetes mellitus (T2DM) inadequately controlled on GLP-1 RAs. However, a comparative cost-effectiveness analysis between these FRCs from a UK Health Service perspective has not been conducted.

METHODS

The IQVIA Core Diabetes Model was used to estimate lifetime costs and outcomes in patients with T2DM receiving iGlarLixi (based on the LixiLan-G trial) versus iDegLira (based on relative treatment effects from an indirect treatment comparison using data from DUAL III). Utilities, medical costs, and costs of diabetes-related complications were derived from literature. Model outputs included costs and quality-adjusted life years (QALYs). Incremental cost-effectiveness ratios were calculated with a local willingness-to-pay threshold of £20,000 per QALY. Extensive scenario, one-way sensitivity, and probabilistic sensitivity analyses were conducted to evaluate the robustness of the model.

RESULTS

iGlarLixi was less costly (iGlarLixi, £30,011; iDegLira, £40,742), owing to lower acquisition costs, and similar in terms of QALYs gained (iGlarLixi, 8.437; iDegLira, 8.422). Extensive scenario and sensitivity analyses supported the base case findings.

CONCLUSION

In patients with T2DM and inadequate glycemic control despite GLP-1 RAs, use of iGlarLixi was associated with substantial cost savings and comparable utility outcomes. iGlarLixi can be considered as cost-effective versus iDegLira from the UK Health Service perspective.

The genetic association of the transcription factor NPAT with glycemic response to metformin involves regulation of fuel selection

The biguanide, metformin, is the first-choice therapeutic agent for type-2 diabetes, although the mechanisms that underpin metformin clinical efficacy remain the subject of much debate, partly due to the considerable variation in patient response to metformin. Identification of poor responders by genotype could avoid unnecessary treatment and provide clues to the underlying mechanism of action. GWAS identified SNPs associated with metformin treatment success at a locus containing the NPAT (nuclear protein, ataxia-telangiectasia locus) and ATM (ataxia-telangiectasia mutated) genes. This implies that gene sequence dictates a subsequent biological function to influence metformin action. Hence, we modified expression of NPAT in immortalized cell lines, primary mouse hepatocytes and mouse tissues, and analysed the outcomes on metformin action using confocal microscopy, immunoblotting and immunocytochemistry. In addition, we characterised the metabolic phenotype of npat heterozygous knockout mice and established the metformin response following development of insulin resistance. NPAT protein was localised in the nucleus at discrete loci in several cell types, but over-expression or depletion of NPAT in immortalised cell models did not change cellular responses to biguanides. In contrast, metformin regulation of respiratory exchange ratio (RER) was completely lost in animals lacking one allele of npat. There was also a reduction in metformin correction of impaired glucose tolerance, however no other metabolic abnormalities, or response to metformin, were found in the npat heterozygous mice. In summary, we provide methodological advancements for the detection of NPAT, demonstrate that minor reductions in NPAT mRNA levels (20–40%) influence metformin regulation of RER, and propose that the association between NPAT SNPs and metformin response observed in GWAS, could be due to loss of metformin modification of cellular fuel usage.

Advancing Therapy in Suboptimally Controlled Basal Insulin-Treated Type 2 Diabetes: Clinical Outcomes With iGlarLixi Versus Premix BIAsp 30 in the SoliMix Randomized Controlled Trial

OBJECTIVE

To directly compare the efficacy and safety of a fixed-ratio combination, of insulin glargine 100 units/mL and the glucagon-like peptide 1 receptor agonist lixisenatide (iGlarLixi), with those of a premix insulin analog, biphasic aspart insulin 30 (30% insulin aspart and 70% insulin aspart protamine) (BIAsp 30) as treatment advancement in type 2 diabetes suboptimally controlled on basal insulin plus oral antihyperglycemic drugs (OADs).

RESEARCH DESIGN AND METHODS

In SoliMix, a 26-week, open-label, multicenter study, adults with suboptimally controlled basal insulin-treated type 2 diabetes (HbA1c ≥7.5% and ≤10%) were randomized to once-daily iGlarLixi or twice-daily BIAsp 30. Primary efficacy end points were noninferiority in HbA1c reduction (margin 0.3%) or superiority in body weight change for iGlarLixi versus BIAsp 30.

RESULTS

Both primary efficacy end points were met: after 26 weeks, baseline HbA1c (8.6%) was reduced by 1.3% with iGlarLixi and 1.1% with BIAsp 30, meeting noninferiority (least squares [LS] mean difference -0.2% [97.5% CI -0.4, -0.1]; P < 0.001). iGlarLixi was also superior to BIAsp 30 for body weight change (LS mean difference -1.9 kg [95% CI -2.3, -1.4]) and percentage of participants achieving HbA1c <7% without weight gain and HbA1c <7% without weight gain and without hypoglycemia (all P < 0.001). iGlarLixi was also superior versus BIAsp 30 for HbA1c reduction (P < 0.001). Incidence and rates of American Diabetes Association level 1 and 2 hypoglycemia were lower with iGlarLixi versus BIAsp 30.

CONCLUSIONS

Once-daily iGlarLixi provided better glycemic control with weight benefit and less hypoglycemia than twice-daily premix BIAsp 30. iGlarLixi is a more efficacious, simpler, and well-tolerated alternative to premix BIAsp 30 in suboptimally controlled type 2 diabetes requiring treatment beyond basal insulin plus OAD therapy. VIDEO 1: diacare;dc21-0393v4/F1F1f1Infographic available at https://care.diabetesjournals.org/content/dc21-0393-infographic.

The suitability of patient-reported outcome measures used to assess the impact of hypoglycaemia on quality of life in people with diabetes: a systematic review using COSMIN methods

AIMS/HYPOTHESIS

It is generally accepted that hypoglycaemia can negatively impact the quality of life (QoL) of people living with diabetes. However, the suitability of patient-reported outcome measures (PROMs) used to assess this impact is unclear. The aim of this systematic review was to identify PROMs used to assess the impact of hypoglycaemia on QoL and examine their quality and psychometric properties.

METHODS

Systematic searches (MEDLINE, EMBASE, PsycINFO, CINAHL and The Cochrane Library databases) were undertaken to identify published articles reporting on the development or validation of hypoglycaemia-specific PROMs used to assess the impact of hypoglycaemia on QoL (or domains of QoL) in adults with diabetes. A protocol was developed and registered with PROSPERO (registration no. CRD42019125153). Studies were assessed for inclusion at title/abstract stage by one reviewer. Full-text articles were scrutinised where considered relevant or potentially relevant or where doubt existed. Twenty per cent of articles were assessed by a second reviewer. PROMS were evaluated, according to COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) guidelines, and data were extracted independently by two reviewers against COSMIN criteria. Assessment of each PROM's content validity included reviewer ratings (N = 16) of relevance, comprehensiveness and comprehensibility: by researchers (n = 6); clinicians (n = 6); and adults with diabetes (n = 4).

RESULTS

Of the 214 PROMs used to assess the impact of hypoglycaemia on QoL (or domains of QoL), seven hypoglycaemia-specific PROMS were identified and subjected to full evaluation: the Fear of Hypoglycemia 15-item scale; the Hypoglycemia Fear Survey; the Hypoglycemia Fear Survey version II; the Hypoglycemia Fear Survey-II short-form; the Hypoglycemic Attitudes and Behavior Scale; the Hypoglycemic Confidence Scale; and the QoLHYPO questionnaire. Content validity was rated as 'inconsistent', with most as '(very) low' quality, while structural validity was deemed 'unsatisfactory'. Other measurement properties (e.g. reliability) varied, and evidence gaps were apparent across all PROMs. None of the identified studies addressed cross-cultural validity or measurement error. Criterion validity and responsiveness were not assessed due to the lack of a 'gold standard' measure of the impact of hypoglycaemia on QoL against which to compare the PROMS.

CONCLUSIONS/INTERPRETATION

None of the hypoglycaemia-specific PROMs identified had sufficient evidence to demonstrate satisfactory validity, reliability and responsiveness. All were limited in terms of content and structural validity, which restricts their utility for assessing the impact of hypoglycaemia on QoL in the clinic or research setting. Further research is needed to address the content validity of existing PROMs, or the development of new PROM(s), for the purpose of assessing the impact of hypoglycaemia on QoL.

PROSPERO REGISTRATION

CRD42019125153.

Marked improvements in glycaemic outcomes following insulin pump therapy initiation in people with type 1 diabetes: a nationwide observational study in Scotland

AIMS/HYPOTHESIS

Our aim was to assess the use of continuous subcutaneous insulin infusion (CSII) in people with type 1 diabetes in Scotland and its association with glycaemic control, as measured by HbA_1c levels, frequency of diabetic ketoacidosis (DKA) and severe hospitalised hypoglycaemia (SHH), overall and stratified by baseline HbA_1c.

METHODS

We included 4684 individuals with type 1 diabetes from the national Scottish register, who commenced CSII between 2004 and 2019. We presented crude within-person differences from baseline HbA_1c over time since initiation, crude DKA and SHH event-rates pre-/post-CSII exposure. We then used mixed models to assess the significance of CSII exposure, taking into account: (1) the diffuse nature of the intervention (i.e. structured education often precedes initiation); (2) repeated within-person measurements; and (3) background time-trends occurring pre-intervention.

RESULTS

HbA_1c decreased after CSII initiation, with a median within-person change of -5.5 mmol/mol (IQR -12.0, 0.0) (-0.5% [IQR -1.1, 0.0]). Within-person changes were most substantial in those with the highest baseline HbA_1c, with median -21.0 mmol/mol (-30.0, -11.0) (-1.9% [-2.7, -1.0]) change in those with a baseline >84 mmol/mol (9.8%) within a year of exposure, that was sustained: -19.0 mmol/mol (-27.6, -6.5) (-1.7% [-2.5, -0.6]) at ≥5 years. Statistical significance and magnitude of change were supported by the mixed models results. The crude DKA event-rate was significantly lower in post-CSII person-time compared with pre-CSII person-time: 49.6 events (95% CI 46.3, 53.1) per 1000 person-years vs 67.9 (64.1, 71.9); rate ratio from Bayesian mixed models adjusting for pre-exposure trend: 0.61 (95% credible interval [CrI] 0.47, 0.77; posterior probability of reduction pp = 1.00). The crude overall SHH event-rate in post-CSII vs pre-CSII person-time was also lower: 17.8 events (95% CI 15.8, 19.9) per 1000 person-years post-exposure vs 25.8 (23.5, 28.3) pre-exposure; rate ratio from Bayesian mixed models adjusting for pre-exposure trend: 0.67 (95% CrI 0.45, 1.01; pp = 0.97).

CONCLUSIONS/INTERPRETATION

CSII therapy was associated with marked falls in HbA_1c especially in those with high baseline HbA_1c. CSII was independently associated with reduced DKA and SHH rates. CSII appears to be an effective option for intensive insulin therapy in people with diabetes for improving suboptimal glycaemic control.

Cold-induced dishabituation in rodents exposed to recurrent hypoglycaemia

AIMS/HYPOTHESIS

Recurrent hypoglycaemia in people with diabetes leads to progressive suppression of counterregulatory hormonal responses to subsequent hypoglycaemia. Recently it has been proposed that the mechanism underpinning this is a form of adaptive memory referred to as habituation. To test this hypothesis, we use two different durations of cold exposure to examine whether rodents exposed to recurrent hypoglycaemia exhibit two characteristic features of habituation, namely stimulus generalisation and dishabituation.

METHODS

In the first study (stimulus generalisation study), hyperinsulinaemic-hypoglycaemic (2.8 mmol/l) glucose clamps were performed in non-diabetic rodents exposed to prior moderate-duration cold (4°C for 3 h) or control conditions. In the second study (dishabituation study), rodents exposed to prior recurrent hypoglycaemia or saline (154 mmol/l NaCl) injections over 4 weeks underwent a longer-duration cold (4°C for 4.5 h) exposure followed 24 h later by a hyperinsulinaemic-hypoglycaemic (2.8 mmol/l) glucose clamp. Output measures were counterregulatory hormone responses during experimental hypoglycaemia.

RESULTS

Moderate-duration cold exposure blunted the adrenaline (epinephrine) response (15,266 ± 1920 vs 7981 ± 1258 pmol/l, Control vs Cold; p < 0.05) to next day hypoglycaemia in healthy non-diabetic rodents. In contrast, the suppressed adrenaline response (Control 5912 ± 1417 vs recurrent hypoglycaemia 1836 ± 736 pmol/l; p < 0.05) that is associated with recurrent hypoglycaemia was restored following longer-duration cold exposure (recurrent hypoglycaemia + Cold 4756 ± 826 pmol/l; not significant vs Control).

CONCLUSIONS/INTERPRETATION

Non-diabetic rodents exhibit two cardinal features of habituation, namely stimulus generalisation and dishabituation. These findings provide further support for the hypothesis that suppressed counterregulatory responses following exposure to recurrent hypoglycaemia in diabetes result from habituation.

Advancing therapy with iGlarLixi versus premix BIAsp 30 in basal insulin-treated type 2 diabetes: Design and baseline characteristics of the SoliMix randomized controlled trial

AIM

Premix insulin is commonly used in some regions of the world, despite the higher risk of hypoglycaemia and weight gain compared with basal insulin, based on the premise that it offers a simplified insulin regimen. iGlarLixi is a once-daily titratable fixed-ratio formulation that combines basal insulin glargine 100 units/mL (iGlar) and the GLP-1 RA, lixisenatide, which offers a single-injection option for treatment intensification, with improved HbA1c reductions, similar hypoglycaemia risk and more favourable bodyweight profiles over iGlar alone. This randomized controlled study directly compares, for the first time, treatment intensification with iGlarLixi versus premix insulin analogue biphasic insulin aspart 30 (BIAsp 30) in adults with T2D inadequately controlled on basal insulin in combination with one or two oral antihyperglycaemic drugs.

MATERIALS AND METHODS

This was an open-label, active-controlled, comparative, parallel-group, multicentre, phase 3b study. In total, 887 adults with T2D uncontrolled on basal insulin were randomized to switch to either iGlarLixi once daily, or BIAsp 30 twice daily, for 26 weeks.

RESULTS

Overall, 887 participants were enrolled (mean age 59.8 years, 50.2% female) from 89 centres in 17 countries. At baseline, 65.6% had a duration of T2D of 10 years or longer, and the mean HbA1c at baseline was 8.6%.

CONCLUSIONS

The study directly compared the efficacy and safety of iGlarLixi versus BIAsp 30 in people with T2D uncontrolled on basal insulin and one or more oral antihyperglycaemic agents. These results provide robust clinical data that may inform clinicians in their therapeutic management of people with T2D uncontrolled on basal insulin requiring additional therapy.

The association of polypharmacy and high-risk drug classes with adverse health outcomes in the Scottish population with type 1 diabetes

AIMS/HYPOTHESIS

The aim of this work was to map the number of prescribed drugs over age, sex and area-based socioeconomic deprivation, and to examine the association between the number of drugs and particular high-risk drug classes with adverse health outcomes among a national cohort of individuals with type 1 diabetes.

METHODS

Utilising linked healthcare records from the population-based diabetes register of Scotland, we identified 28,245 individuals with a diagnosis of type 1 diabetes on 1 January 2017. For this population, we obtained information on health status, predominantly reflecting diabetes-related complications, and information on the total number of drugs and particular high-risk drug classes prescribed. We then studied the association of these baseline-level features with hospital admissions for falls, diabetic ketoacidosis (DKA), and hypoglycaemia or death within the subsequent year using multivariate Cox proportional hazards models.

RESULTS

Not considering insulin and treatment for hypoglycaemia, the mean number of prescribed drugs was 4.00 (SD 4.35). The proportion of individuals being prescribed five or more drugs at baseline consistently increased with age (proportion [95% CI]: 0-19 years 2.04% [1.60, 2.49]; 40-49 years 28.50% [27.08, 29.93]; 80+ years 76.04% [67.73, 84.84]). Controlling for age, sex, area-based socioeconomic deprivation and health status, each additional drug at baseline was associated with an increase in the hazard for hospitalisation for falls, hypoglycaemia and death but not for DKA admissions (HR [95% CI]: falls 1.03 [1.01, 1.06]; DKA 1.01 [1.00, 1.03]; hypoglycaemia 1.05 [1.02, 1.07]; death 1.04 [1.02, 1.06]). We found a number of drug classes to be associated with an increased hazard of one or more of these adverse health outcomes, including antithrombotic/anticoagulant agents, corticosteroids, opioids, antiepileptics, antipsychotics, hypnotics and sedatives, and antidepressants.

CONCLUSIONS

Polypharmacy is common among the Scottish population with type 1 diabetes and is strongly patterned by sociodemographic factors. The number of prescribed drugs and the prescription of particular high-risk drug classes are strong markers of an increased risk of adverse health outcomes, including acute complications of diabetes.

Consequences of recurrent hypoglycaemia on brain function in diabetes

The discovery of insulin and its subsequent mass manufacture transformed the lives of people with type 1 and 2 diabetes. Insulin, however, was a drug with a 'dark side'. It brought with it the risk of iatrogenic hypoglycaemia. In this short review, the cellular consequences of recurrent hypoglycaemia, with a particular focus on the brain, are discussed. Using the ventromedial hypothalamus as an exemplar, this review highlights how recurrent hypoglycaemia has an impact on the specialised cells in the brain that are critical to the regulation of glucose homeostasis and the counterregulatory response to hypoglycaemia. In these cells, recurrent hypoglycaemia initiates a series of adaptations that ensure that they are more resilient to subsequent hypoglycaemia, but this leads to impaired hypoglycaemia awareness and a paradoxical increased risk of severe hypoglycaemia. This review also highlights how hypoglycaemia, as an oxidative stressor, may also exacerbate chronic hyperglycaemia-induced increases in oxidative stress and inflammation, leading to damage to vulnerable brain regions (and other end organs) and accelerating cognitive decline. Pre-clinical research indicates that glucose recovery following hypoglycaemia is considered a period where reactive oxygen species generation and oxidative stress are pronounced and can exacerbate the longer-term consequence of chronic hypoglycaemia. It is proposed that prior glycaemic control, hypoglycaemia and the degree of rebound hyperglycaemia interact synergistically to accelerate oxidative stress and inflammation, which may explain why increased glycaemic variability is now increasingly considered a risk factor for the complications of diabetes.

Hyperinsulinaemic-hypoglycaemic glucose clamps in human research: a systematic review of the literature

AIMS/HYPOTHESIS

The hyperinsulinaemic-hypoglycaemic glucose clamp technique has been developed and applied to assess effects of and responses to hypoglycaemia under standardised conditions. However, the degree to which the methodology of clamp studies is standardised is unclear. This systematic review examines how hyperinsulinaemic-hypoglycaemic clamps have been performed and elucidates potential important differences.

METHODS

A literature search in PubMed and EMBASE was conducted. Articles in English published between 1980 and 2018, involving adults with or without diabetes, were included.

RESULTS

A total of 383 articles were included. There was considerable variation in essential methodology of the hypoglycaemic clamp procedures, including the insulin dose used (49-fold difference between the lowest and the highest rate), the number of hypoglycaemic steps (range 1-6), the hypoglycaemic nadirs (range 2.0-4.3 mmol/l) and the duration (ranging from 5 to 660 min). Twenty-seven per cent of the articles reported whole blood glucose levels, most venous levels. In 70.8% of the studies, a dorsal hand vein was used for blood sampling, with some form of hand warming to arterialise venous blood in 78.8% of these. Key information was missing in 61.9% of the articles.

CONCLUSIONS/INTERPRETATION

Although the hyperinsulinaemic-hypoglycaemic clamp procedure is considered the gold standard to study experimental hypoglycaemia, a uniform standard with key elements on how to perform these experiments is lacking. Methodological differences should be considered when comparing results between hypoglycaemic clamp studies.

PROSPERO REGISTRATION

This systematic review is registered in PROSPERO (CRD42019120083).

Adipocyte integrin-linked kinase plays a key role in the development of diet-induced adipose insulin resistance in male mice

Objective

Increased deposition of the extracellular matrix (ECM) in adipose tissue (AT) during obesity contributes to insulin resistance. The integrin receptors transmit changes in the extracellular environment causing corresponding intracellular adaptations. Integrin-linked kinase (ILK), an adaptor protein, is a central hub for intracellular signaling of integrins. This study determined the role of ILK in adipose function and insulin resistance.

Methods

The pathogenic role of ILK in obesity and insulin resistance was studied in human adipose tissue and adipocyte-specific ILK-deficient mice (ILK^lox/loxAdCre). ILK^lox/loxAdCre mice together with wild-type littermates (ILK^lox/lox) were fed a chow diet or 60% high-fat (HF) diet for 16 weeks. In vivo insulin sensitivity was determined by hyperinsulinemic-euglycemic clamps.

Results

AT ILK expression was increased by HF diet feeding in mice and increased in visceral fat of morbidly obese humans. The HF-fed ILK^lox/loxAdCre mice displayed reduced fat mass and improved glucose tolerance relative to the HF-fed ILK^lox/lox mice. During a hyperinsulinemic-euglycemic clamp, the HF-fed ILK^lox/loxAdCre mice exhibited partially improved insulin resistance in AT. Lipolysis was suppressed to a greater extent by insulin and glucose uptake in brown AT (BAT) increased. Increased inhibition of lipolysis may have been attributed to increased vascularization in white AT, while increased glucose uptake in BAT was associated with increased Akt phosphorylation and P38/JNK dephosphorylation. Notably, AT insulin sensitivity in lean mice was not affected by ILK deletion. Moreover, reduced fat mass in the HF-fed ILK^lox/loxAdCre mice may have been attributed to decreased free fatty acid uptake into adipocytes via the downregulation of CD36 gene expression. Consistent with the results in the mice, knockdown and knockout of ILK in 3T3-L1 cells decreased lipid accumulation and CD36 gene expression during adipogenesis.

Conclusions

These data show that adipocyte ILK is important for regulating HF diet-mediated insulin resistance in AT in a manner consistent with AT function.

•

ILK protein increased in visceral adipose tissue of obese humans and mice.

•

Mice lacking adipocyte ILK had less fat and improved glucose tolerance in obesity.

•

Adipocyte ILK deletion improved anti-lipolytic action of insulin in obese mice.

•

Adipocyte ILK deletion stimulated brown adipose tissue glucose uptake in obese mice.

Loss of O-GlcNAcase catalytic activity leads to defects in mouse embryogenesis

O-GlcNAcylation is an essential post-translational modification that has been implicated in neurodevelopmental and neurodegenerative disorders. O-GlcNAcase (OGA), the sole enzyme catalyzing the removal of O-GlcNAc from proteins, has emerged as a potential drug target. OGA consists of an N-terminal OGA catalytic domain and a C-terminal pseudo histone acetyltransferase (HAT) domain with unknown function. To investigate phenotypes specific to loss of OGA catalytic activity and dissect the role of the HAT domain, we generated a constitutive knock-in mouse line, carrying a mutation of a catalytic aspartic acid to alanine. These mice showed perinatal lethality and abnormal embryonic growth with skewed Mendelian ratios after day E18.5. We observed tissue-specific changes in O-GlcNAc homeostasis regulation to compensate for loss of OGA activity. Using X-ray microcomputed tomography on late gestation embryos, we identified defects in the kidney, brain, liver, and stomach. Taken together, our data suggest that developmental defects during gestation may arise upon prolonged OGA inhibition specifically because of loss of OGA catalytic activity and independent of the function of the HAT domain.