Glucagon-like peptide-1 receptor agonists and kidney outcomes.

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have gained increasing attention for their potential benefits in people with type 2 diabetes mellitus (T2DM) with chronic kidney disease (CKD). Most supportive evidence of a kidney-protective effect of the GLP-1RA class of medications has been derived from kidney-related outcomes reported from cardiovascular outcome trials (CVOTs). GLP-1RAs have been shown to reduce albuminuria, mitigate cardiovascular risk, and possibly attenuate estimated glomerular filtration rate (eGFR) decline. The kidney-protective effects of GLP-1RAs are thought to be attributed to their anti-inflammatory, antioxidant, and vasodilatory properties. Despite these promising findings, the use of GLP-RAs has yet to be definitively shown to slow progression to chronic kidney failure in people with T2DM. The Research Study to See How Semaglutide Works Compared to Placebo in People With Type 2 Diabetes and Chronic Kidney Disease (FLOW trial) is the first major trial assessing the potential of a GLP-1RA to slow progression of kidney disease in people with established CKD to clinically important kidney end points. On March 5, 2024, the top line result from FLOW was announced with semaglutide 1.0 mg being reported to reduce the primary end point of the trial by a significant 24% compared with placebo. Here, we summarize the kidney outcomes reported from CVOTs for the GLP-1RA class of medication and briefly describe kidney outcomes from other major GLP-1RAs trials. We also discuss a potential role of the dual GLP-1/glucose-dependent insulinotropic polypeptide (GIP) receptor agonist, tirzepatide, as a kidney-protective agent.

Effects of Semaglutide on Heart Failure Outcomes in Diabetes and Chronic Kidney Disease in the FLOW Trial.

BACKGROUND: People with type 2 diabetes (T2D) and chronic kidney disease (CKD) are at high risk for heart failure (HF) and premature death from cardiovascular (CV) causes. The FLOW (Research Study To See How Semaglutide Works Compared to Placebo in People With Type 2 Diabetes and Chronic Kidney Disease), which enrolled participants with T2D and CKD, demonstrated that semaglutide, a glucagon-like peptide-1 receptor agonist, reduced the incidence of the primary composite outcome (persistent ≥50% decline in estimated glomerular filtration rate, persistent estimated glomerular filtration rate <15 mL/min/1.73 m2, kidney replacement therapy, and kidney or CV death) by 24%. OBJECTIVES: This prespecified analysis examined the effects of semaglutide on HF outcomes in this high-risk population. METHODS: Participants were randomized (1:1) to once-weekly subcutaneous semaglutide 1 mg or placebo. The prespecified main outcome was a composite of HF events (new onset or worsening of HF leading to an unscheduled hospital admission or an urgent visit, with initiation of or intensified diuretic/vasoactive therapy) or CV death. HF data were collected by the investigator. CV death was adjudicated by an independent committee. RESULTS: A total of 3,533 randomized participants were followed for a median of 3.4 years. HF was present at baseline in 342 participants (19.4%) in the semaglutide group and 336 (19.0%) in the placebo group. In the overall trial population, semaglutide increased time to first HF events or CV death (HR: 0.73; 95% CI: 0.62-0.87; P = 0.0005), HF events alone (HR: 0.73; 95% CI: 0.58-0.92; P = 0.0068), and CV death alone (HR: 0.71; 95% CI: 0.56-0.89; P = 0.0036). The risk reduction for the composite HF outcome was similar in those with (HR: 0.73; 95% CI: 0.54-0.98; P = 0.0338) and without (HR: 0.72; 95% CI: 0.58-0.89; P = 0.0028) HF at baseline. The risk of HF outcomes (HF events or CV death) was generally higher in participants categorized as NYHA functional class III and those with the HF reduced ejection fraction subtype, regardless of treatment. CONCLUSIONS: Semaglutide substantially reduced the risk of time to first composite outcome of HF events or CV death, as well as HF events and CV death alone, in a high-risk population with T2D and CKD. These effects were consistent regardless of history of HF. (A Research Study To See How Semaglutide Works Compared to Placebo in People With Type 2 Diabetes and Chronic Kidney Disease [FLOW]; NCT03819153).

Tear neuropeptide Y as a non-invasive marker of peripheral microvascular complications in type 1 diabetes.

AIMS: To investigate tear neuropeptide Y (NPY) and substance P concentrations in individuals with type 1 diabetes, comparing those with and without both diabetic retinopathy (DR) and peripheral neuropathy. METHODS: This cross-sectional study involved 41 participants with type 1 diabetes and none to moderate DR, and 22 healthy controls. Assessments included clinical ocular surface parameters, quantification of corneal nerve attributes (based on in vivo confocal microscopy imaging), DR grading, and evaluation for small and large fibre neuropathy. Concentrations of NPY and substance P in tear samples were measured using enzyme-linked immunosorbent assay. RESULTS: Mean (± standard deviation) tear NPY concentrations in participants with type 1 diabetes and length-dependent small fibre neuropathy (SFN) was lower than in controls (10.84 ± 4.10 ng/mL vs 14.72 ± 3.12 ng/mL; p=0.004), but not significantly different from type 1 diabetes participants without SFN (13.39 ± 4.66 ng/mL; p=0.11). Tear NPY levels were lower in individuals with type 1 diabetes and mild/moderate non-proliferative DR (10.44 ± 3.46 ng/mL) compared to none/minimal DR (13.79 ± 4.76 ng/mL; p=0.0005) and controls. In separate linear regression models, both the presence of SFN (ß = -0.75, p=0.02) and the presence of mild/moderate DR (ß = -0.84, p=0.009) were significantly associated with tear NPY levels relative to controls, after adjusting for participant age, sex, and dry eye disease. There were no inter-group differences for tear substance P concentrations. CONCLUSIONS: Tear NPY has potential utility as an indicator of peripheral microvascular complications associated with type 1 diabetes.

Utility of Adrenal Vein Sampling With and Without Ultra-Low Dose ACTH Infusion in the Diagnostic Evaluation of Primary Aldosteronism.

BACKGROUND: Adrenal vein sampling (AVS), integral to identifying surgically remediable unilateral primary aldosteronism (PA), is technically challenging and subject to fluctuations in cortisol and aldosterone secretion. Intra-procedural adrenocorticotropic hormone (ACTH), conventionally administered as a 250-µg bolus and/or 50 µg per hour infusion, increases cortisol and aldosterone secretion and can improve AVS success, but may cause discordant lateralisation compared to unstimulated AVS. AIMS: To assess if AVS performed with ultra-low dose ACTH infusion causes discordant lateralisation. METHODS: Here, we describe our preliminary experience using an ultra-low dose ACTH infusion AVS protocol. We retrospectively reviewed the results of consecutive AVS procedures (n = 37) performed with and without ultra-low dose ACTH (1-µg bolus followed by 1.25 µg per hour infusion). RESULTS: Bilateral AV cannulation was successful in 70% of procedures pre-ACTH and 89% post-ACTH (p < 0.01). Sixty-nine percent of studies lateralised pre-ACTH and 55% post-ACTH, improving to 79% when both groups were combined. Lateralisation was discordant in 11 cases, including eight in which lateralisation was present only on basal sampling, and three in which lateralisation occurred only with ACTH stimulation. DISCUSSION: Overall, the decrease in lateralisation rates with ACTH was higher than previously reported for some protocols utilising conventional doses of ACTH. Our results suggest that AVS performed with ultra-low dose ACTH can cause discordant lateralisation similar to AVS performed with conventional doses of ACTH. CONCLUSION: Prospective studies directly comparing low and conventional dose ACTH AVS protocols and long-term patient outcomes are needed to help define the optimal ACTH dose for accurate PA subtyping.

Potential kidney protective effects of glucagon-like peptide-1 receptor agonists.

Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have gained increasing attention for their potential benefits in people with type 2 diabetes (T2DM) with chronic kidney disease (CKD). This class of medication has demonstrated promising results in reducing albuminuria, preserving estimated glomerular filtration rate (eGFR), and mitigating cardiovascular (CV) risk, making them potential therapeutic options for individuals with CKD. The kidney protective effects of GLP-1RAs extend beyond glycaemic control, and are thought to be attributed to their anti-inflammatory, antioxidant, and natriuretic properties. Despite these promising findings, the use of GLP-RAs has yet to be definitively shown to slow progression to chronic kidney failure, or reduce CV and kidney related death in people with T2DM and CKD. The Research Study to See How Semaglutide (a once weekly subcutaneous administered GLP-1RA) Works Compared to Placebo in People with Type 2 Diabetes and Chronic Kidney Disease (FLOW trial) was recently stopped because of efficacy. The primary end point for the FLOW trial consists of a composite endpoint of (i) onset of chronic kidney failure; (ii) death from kidney failure; (iii) cardiovascular death; and (iv) onset of a persistent ≥50% reduction in eGFR from baseline. It has also been reported by the sponsors of the trial that the primary end point of the trial was reduced by 24% with both CKD and CV outcomes contributing to risk reduction. In anticipation of the results of the FLOW trial being published, we review the current evidence surrounding kidney outcomes and proposed kidney protective pathways associated with GLP-1RA use.

Trends in diabetic ketoacidosis in Victoria, Australia 2002-2016.

BACKGROUND: International longitudinal studies have indicated an increasing incidence of diabetic ketoacidosis (DKA). We aim to examine the incident trends, demographic differences, length of stay and mortality for DKA in adults with type 1 diabetes (T1D) and type 2 diabetes (T2D) in Victoria, Australia from 2002 to 2016. METHODS: Age and sex adjusted incident trends, length of stay and mortality for DKA was retrospectively obtained using the Victorian Admitted Episode Dataset between 2002 and 2016. Data for adults with T1D and T2D was obtained from the National Diabetes Services Scheme (NDSS). Joinpoint regression analysis was used to identify changes in linear trends that were described as average annual percentage change (AAPC). RESULTS: There were 23,628 DKA presentations in Victoria between 2002 and 2016. For T1D there was an increase in DKA presentations (AAPC + 6.8%) from 2003 to 2016 and for T2D there was a decline from 2003 to 2011 (APC - 3.5%), increase from 2011 to 2014 (APC + 38.5%), and a decrease from 2014 to 2016 (APC - 20.9%). Length of stay was longer for people with T2D than T1D (P < 0.001) and the mortality rate was 0.51% for the study period. CONCLUSIONS: DKA rates increased for T2D from 2011 to 2014 which correlates with the introduction of sodium glucose-linked transport protein 2 inhibitors. However, the aetiology for the observed increase in T1D from 2002 to 2016 remains unknown.

Accuracy and Feasibility of a Novel Glucose/Lactate Continuous Multi-Analyte Sensing Platform in Humans.

BACKGROUND AND AIM: Continuous glucose monitoring systems (CGMs) have been commercially available since 1999. However, automated insulin delivery systems may benefit from real-time inputs in addition to glucose. Continuous multi-analyte sensing platforms will meet this area of potential growth without increasing the burden of additional devices. We aimed to generate pilot data regarding the safety and function of a first-in-human, single-probe glucose/lactate multi-analyte continuous sensor. METHODS: The investigational glucose/lactate continuous multi-analyte sensor (PercuSense Inc, Valencia, California) was inserted to the upper arms of 16 adults with diabetes, and data were available for analysis from 11 of these participants (seven female; mean [SD] = age 43 years [16]; body mass index [BMI] = 27 kg/m2 [5]). A commercially available Guardian 3 CGM (Medtronic, Northridge, California) was also inserted into the abdomen for comparison. All participants underwent a meal-test followed by an exercise challenge on day 1 and day 4 of wear. Performance was benchmarked against venous blood YSI glucose and lactate values. RESULTS: The investigational glucose sensor had an overall mean absolute relative difference (MARD) of 14.5% (median = 11.2%) which improved on day 4 compared with day 1 (13.9% vs 15.2%). The Guardian 3 CGM had an overall MARD of 13.9% (median = 9.4%). The lactate sensor readings within 20/20% and 40/40% of YSI values were 59.7% and 83.1%, respectively. CONCLUSIONS: Our initial data support safety and functionality of a novel glucose/lactate continuous multi-analyte sensor. Further sensor refinement will improve run-in performance and accuracy.

Hybrid Closed Loop in Adults With Type 1 Diabetes and Severely Impaired Hypoglycemia Awareness.

BACKGROUND: Benefits of hybrid closed-loop (HCL) systems in a high-risk group with type 1 diabetes and impaired awareness of hypoglycemia (IAH) have not been well-explored. METHODS: Adults with Edmonton HYPO scores ≥1047 were randomized to 26-weeks HCL (MiniMed™ 670G) vs standard therapy (multiple daily injections or insulin pump) without continuous glucose monitoring (CGM) (control). Primary outcome was percentage CGM time-in-range (TIR; 70-180 mg/dL) at 23 to 26 weeks post-randomization. Major secondary endpoints included magnitude of change in counter-regulatory hormones and autonomic symptom responses to hypoglycemia at 26-weeks post-randomization. A post hoc analysis evaluated glycemia risk index (GRI) comparing HCL with control groups at 26 weeks post-randomization. RESULTS: Nine participants (median [interquartile range (IQR)] age 51 [41, 59] years; 44% male; enrolment HYPO score 1183 [1058, 1308]; Clarke score 6 [6, 6]; n = 5 [HCL]; n = 4 [control]) completed the study. Time-in-range was higher using HCL vs control (70% [68, 74%] vs 48% [44, 50%], P = .014). Time <70 mg/dL did not differ (HCL 3.8% [2.7, 3.9] vs control 6.5% [4.3, 8.6], P = .14) although hypoglycemia episode duration was shorter (30 vs 50 minutes, P < .001) with HCL. Glycemia risk index was lower with HCL vs control (38.1 [30.0, 39.2] vs 70.8 [58.5, 72.4], P = .014). Following 6 months of HCL use, greater dopamine (24.0 [12.3, 27.6] vs -18.5 [-36.5, -4.8], P = .014), and growth hormone (6.3 [4.6, 16.8] vs 0.5 [-0.8, 3.0], P = .050) responses to hypoglycemia were observed. CONCLUSIONS: Six months of HCL use in high-risk adults with severe IAH increased glucose TIR and improved GRI without increased hypoglycemia, and partially restored counter-regulatory responses. CLINICAL TRIAL REGISTRATION: ACTRN12617000520336.

Utility of Repeat Sampling in Bilateral Aldosterone Suppression During Adrenal Vein Sampling for Primary Aldosteronism.

Primary aldosteronism (PA) is the most common form of secondary hypertension. Accurate subtyping of PA is essential to identify unilateral disease, as adrenalectomy improves outcomes. Subtyping PA requires adrenal vein sampling (AVS), which is technically challenging and results from AVS may not always be conclusive. We present a case of a 37-year-old man with PA whose AVS studies were inconclusive due to apparent bilateral aldosterone suppression (ABAS). As a result, our patient was misdiagnosed as having bilateral PA and medically managed until a repeat AVS showed lateralization to the right adrenal gland. ABAS is an underrecognized phenomenon that may confound the subtyping of PA. We recommend repeating AVS in such cases and discuss strategies to minimize ABAS.

Outcomes associated with a variable rate insulin infusion diabetic ketoacidosis protocol.

AIMS: To relate adverse events with glucose correction rates in diabetic ketoacidosis (DKA) using variable rate intravenous insulin-infusions (VRIII). METHODS: Retrospective, observational study in adults with DKA who received insulin infusions between 2012 and 2017 at St Vincent's Hospital, Melbourne. Early correction of hyperglycaemia (<10 mmol/L) was evaluated for association with hypoglycaemia (<4.0 mmol/L), hypokalaemia (potassium <3.3 mmol/L) and clinical outcomes via regression analysis. RESULTS: The study involved 97 patients, with 93 % having type 1 diabetes. The mean age was 38 years, 47 % were women and 35 % were admitted to intensive care. Hypoglycaemia rates during 12 and 24 h of treatment were 6.2 % and 8.2 %, respectively with 58 % of patients recording their first BGL <10 mmol/L within 12 h and 88 % within 24 h. Ketone clearance time averaged at 15.6 h. Hyperglycaemia correction rates to <10 mmol/L were not different in those with/without hypoglycaemia at 12/24 h, in multivariate analysis including admission BGL. Hypokalaemia occurred in 40.2 % of patients and was associated with lower pH but not BGL correction rates. CONCLUSION: The VRIII protocol achieved early hyperglycaemia correction and ketoacidosis reversal with low hypoglycaemia risk. However, high hypokalaemia rates suggest the need for aggressive potassium replacement, especially in markedly acidotic patients.

Driving-Related Glucose Patterns Among Older Adults with Type 1 Diabetes.

Older adults with type 1 diabetes may face challenges driving safely. Glucose "above-5-to-drive" is often recommended for insulin-treated diabetes to minimize hypoglycemia while driving. However, the effectiveness of this recommendation among older adults has not been evaluated. Older drivers with type 1 diabetes were assessed while using sensor-augmented insulin pumps during a 2-week clinical trial run-in. Twenty-three drivers (median age 69 years [interquartile range; IQR 65-72]; diabetes duration 37 years [20-45]) undertook 618 trips (duration 10 min [5-21]). Most trips (n = 535; 87%) were <30 min duration; 9 trips (1.5%) exceeded 90 min and 3 trips (0.5%) exceeded 120 min. Pre-trip continuous glucose monitoring (CGM) was >5.0 mmol/L for 577 trips (93%) and none of these had CGM <3.9 mmol/L during driving (including 8 trips >90 min and 3 trips >120 min). During 41 trips with pre-trip CGM ≤5.0 mmol/L, 11 trips had CGM <3.9 mmol/L. Seventy-one CGM alerts occurred during 60 trips (10%), of which 54 of 71 alerts (76%) were unrelated to hypoglycemia. Our findings support a glucose "above-5-to-drive" recommendation to avoid CGM-detected hypoglycemia among older drivers, including for prolonged drives, and highlight the importance of active CGM low-glucose alerts to prevent hypoglycemia during driving. Driving-related CGM usability and alert functionality warrant investigation. Clinical trial ACTRN1261900515190.

Automated insulin delivery among adults with type 1 diabetes for up to 2 years: a real-world, multicentre study.

BACKGROUND AND AIMS: Automated insulin delivery (AID) improves glycaemia among people with type 1 diabetes in clinical trials and overseas real-world studies. Whether improvements are sustained beyond 12 months in the real world, and whether they occur in the Australian context, has not yet been established. We aimed to observe, up to 2 years, the effectiveness of initiating first-generation AID for type 1 diabetes management. METHODS: Retrospective, real-world, observational study using medical records, conducted across five sites in Australia. Adults with type 1 diabetes, who had AID initiated between February 2019 and December 2021, were observed for 6-24 months after initiation (until June 2022). Outcomes examined included glucose metrics assessed by glycated haemoglobin (HbA1c ) and continuous glucose monitoring (CGM), safety and therapy continuation. RESULTS: Ninety-four adults were studied (median age 39 years (interquartile range, IQR: 31-51); pre-initiation HbA1c 7.8% (7.2-8.6)). After AID initiation, HbA1c decreased by mean 0.5 percentage points (95% confidence interval (CI): -0.7 to -0.2) at 3 months (P < 0.001); CGM time in range 3.9-10.0 mmol/L increased by 11 percentage points (9-14) at 1 month (P < 0.001); these improvements were maintained up to 24 months (all P < 0.02). Median CGM time below 3.9 mmol/L was <1.5% pre- and post-AID initiation. The subgroup with pre-initiation HbA1c above 8.5% had the greatest HbA1c improvement (-1.4 percentage points (-1.8 to -1.1) at 3 months). Twelve individuals (13%) discontinued AID, predominantly citing difficulties with CGM. During the 150 person-years observed, four diabetes-related emergencies were documented: three severe hypoglycaemic events and one hyperglycaemic event without ketoacidosis. CONCLUSIONS: Early glucose improvements were observed after real-world AID initiation, sustained up to 2 years, without excess adverse events. The greatest benefits were observed among individuals with highest glycaemia before initiation. Future-generation systems with increased user-friendliness may enhance therapy continuation.

Baricitinib and ß-Cell Function in Patients with New-Onset Type 1 Diabetes.

BACKGROUND: Janus kinase (JAK) inhibitors, including baricitinib, block cytokine signaling and are effective disease-modifying treatments for several autoimmune diseases. Whether baricitinib preserves ß-cell function in type 1 diabetes is unclear. METHODS: In this phase 2, double-blind, randomized, placebo-controlled trial, we assigned patients with type 1 diabetes diagnosed during the previous 100 days to receive baricitinib (4 mg once per day) or matched placebo orally for 48 weeks. The primary outcome was the mean C-peptide level, determined from the area under the concentration-time curve, during a 2-hour mixed-meal tolerance test at week 48. Secondary outcomes included the change from baseline in the glycated hemoglobin level, the daily insulin dose, and measures of glycemic control assessed with the use of continuous glucose monitoring. RESULTS: A total of 91 patients received baricitinib (60 patients) or placebo (31 patients). The median of the mixed-meal-stimulated mean C-peptide level at week 48 was 0.65 nmol per liter per minute (interquartile range, 0.31 to 0.82) in the baricitinib group and 0.43 nmol per liter per minute (interquartile range, 0.13 to 0.63) in the placebo group (P = 0.001). The mean daily insulin dose at 48 weeks was 0.41 U per kilogram of body weight per day (95% confidence interval [CI], 0.35 to 0.48) in the baricitinib group and 0.52 U per kilogram per day (95% CI, 0.44 to 0.60) in the placebo group. The levels of glycated hemoglobin were similar in the two trial groups. However, the mean coefficient of variation of the glucose level at 48 weeks, as measured by continuous glucose monitoring, was 29.6% (95% CI, 27.8 to 31.3) in the baricitinib group and 33.8% (95% CI, 31.5 to 36.2) in the placebo group. The frequency and severity of adverse events were similar in the two trial groups, and no serious adverse events were attributed to baricitinib or placebo. CONCLUSIONS: In patients with type 1 diabetes of recent onset, daily treatment with baricitinib over 48 weeks appeared to preserve ß-cell function as estimated by the mixed-meal-stimulated mean C-peptide level. (Funded by JDRF International and others; BANDIT Australian New Zealand Clinical Trials Registry number, ACTRN12620000239965.).

Challenging Clinical Perspectives in Type 2 Diabetes with Tirzepatide, a First-in-Class Twincretin.

Tirzepatide is a first-in-class GIP/GLP-1 receptor agonist ('twincretin')-a single molecule that acts as an agonist at both glucagon-like peptide 1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP) receptors. In the SURPASS clinical trial program in type 2 diabetes mellitus (T2D), tirzepatide was associated with unprecedented reductions in HbA1c, clinically significant weight loss and other metabolic benefits, combined with low rates of hypoglycaemia across a wide range of patient characteristics. The safety and adverse event rate for tirzepatide appears comparable to that of GLP-1 receptor agonists. Although results from dedicated cardiovascular (CV) and kidney trials are currently not available, information to date suggests that tirzepatide may have CV and kidney benefits in people with T2D. Tirzepatide has been approved for the treatment of T2D in the USA, United Arab Emirates, European Union, Japan and Australia. Here, we review how tirzepatide will fit into the T2D treatment continuum. We also consider future directions with tirzepatide in T2D, including its potential for targeting cardio-renal-metabolic disease in T2D, and discuss how tirzepatide-and other co-agonists in development-may challenge current approaches for management of T2D.

Detection, management, and prevention of diabetes-related foot disease in the Australian context.

Diabetes-related foot disease (DFD) is a widely feared complication among people who live with diabetes. In Australia and globally, rates of disability, cardio-vascular disease, lower extremity amputation, and mortality are significantly increased in patients with DFD. In order to understand and prevent these outcomes, we analyse the common pathogenetic processes of neuropathy, arterial disease, and infection. The review then summarises important management considerations through the interdisciplinary lens. Using Australian and international guidelines, we offer a stepwise, evidence-based practical approach to the care of patients with DFD.

Stimulation parameters for directional vagus nerve stimulation.

BACKGROUND: Autonomic nerve stimulation is used as a treatment for a growing number of diseases. We have previously demonstrated that application of efferent vagus nerve stimulation (eVNS) has promising glucose lowering effects in a rat model of type 2 diabetes. This paradigm combines high frequency pulsatile stimulation to block nerve activation in the afferent direction with low frequency stimulation to activate the efferent nerve section. In this study we explored the effects of the parameters for nerve blocking on the ability to inhibit nerve activation in the afferent direction. The overarching aim is to establish a blocking stimulation strategy that could be applied using commercially available implantable pulse generators used in the clinic. METHODS: Male rats (n = 20) had the anterior abdominal vagus nerve implanted with a multi-electrode cuff. Evoked compound action potentials (ECAP) were recorded at the proximal end of the electrode cuff. The efficacy of high frequency stimulation to block the afferent ECAP was assessed by changes in the threshold and saturation level of the response. Blocking frequency and duty cycle of the blocking pulses were varied while maintaining a constant 4 mA current amplitude. RESULTS: During application of blocking at lower frequencies (≤ 4 kHz), the ECAP threshold increased (ANOVA, p < 0.001) and saturation level decreased (p < 0.001). Application of higher duty cycles (> 70%) led to an increase in evoked neural response threshold (p < 0.001) and a decrease in saturation level (p < 0.001). During the application of a constant pulse width and frequency (1 or 1.6 kHz, > 70% duty cycle), the charge delivered per pulse had a significant influence on the magnitude of the block (ANOVA, p = 0.003), and was focal (< 2 mm range). CONCLUSIONS: This study has determined the range of frequencies, duty cycles and currents of high frequency stimulation that generate an efficacious, focal axonal block of a predominantly C-fiber tract. These findings could have potential application for the treatment of type 2 diabetes.

Challenges of Glycemic Control in People With Diabetes and Advanced Kidney Disease and the Potential of Automated Insulin Delivery.

Diabetes is the leading cause of chronic kidney disease (CKD) and end-stage kidney disease in the world. It is known that maintaining optimal glycemic control can slow the progression of CKD. However, the failing kidney impacts glucose and insulin metabolism and contributes to increased glucose variability. Conventional methods of insulin delivery are not well equipped to adapt to this increased glycemic lability. Automated insulin delivery (AID) has been established as an effective treatment in patients with type 1 diabetes mellitus, and there is emerging evidence for their use in type 2 diabetes mellitus. However, few studies have examined their role in diabetes with concurrent advanced CKD. We discuss the potential benefits and challenges of AID use in patients with diabetes and advanced CKD, including those on dialysis.