Effect of 6 months of hybrid closed-loop insulin delivery in adults with type 1 diabetes: a randomised controlled trial protocol

INTRODUCTION: Manual determination of insulin dosing largely fails to optimise glucose control in type 1 diabetes. Automated insulin delivery via closed-loop systems has improved glucose control in short-term studies. The objective of the present study is to determine the effectiveness of 6 months\u27 closed-loop compared with manually determined insulin dosing on time-in-target glucose range in adults with type 1 diabetes. METHODS AND ANALYSIS: This open-label, seven-centre, randomised controlled parallel group clinical trial will compare home-based hybrid closed-loop versus standard diabetes therapy in Australia. Adults aged ≥25 years with type 1 diabetes using intensive insulin therapy (via multiple daily injections or insulin pump, total enrolment target n=120) will undertake a run-in period including diabetes and carbohydrate-counting education, clinical optimisation and baseline data collection. Participants will then be randomised 1:1 either to 26 weeks of MiniMed 670G hybrid closed-loop system therapy (Medtronic, Northridge, CA, USA) or continuation of their current diabetes therapy. The hybrid closed-loop system delivers insulin automatically to address basal requirements and correct to target glucose level, while bolus doses for meals require user initiation and carbohydrate estimation. Analysis will be intention to treat, with the primary outcome time in continuous glucose monitoring (CGM) target range (3.9-10.0 mmol/L) during the final 3 weeks of intervention. Secondary outcomes include: other CGM parameters, HbA1c, severe hypoglycaemia, psychosocial well-being, sleep, cognition, electrocardiography, costs, quality of life, biomarkers of vascular health and hybrid closed-loop system performance. Semistructured interviews will assess the expectations and experiences of a subgroup of hybrid closed-loop users. ETHICS AND DISSEMINATION: The study has Human Research Ethics Committee approval. The study will be conducted in accordance with the principles of the Declaration of Helsinki and Good Clinical Practice. Results will be disseminated at scientific conferences and via peer-reviewed publications

Resources to guide exercise specialists managing adults with diabetes

Exercise is an important element to optimize health and well-being, though navigating exercise safely can be challenging for exercise specialists working with people with diabetes. Measuring glucose levels before an exercise session assists in the determination of whether exercise is safe for a person with diabetes. A number of organizations have recently developed guidelines to provide exercise and diabetes recommendations based on glucose levels and other relevant factors. However, there are limited easy-to-use resources to assist exercise specialists to determine whether exercise should be started and continued by people with diabetes. The type of diabetes, pre-exercise glucose level, medications and their timing, recent food intake and general sense of wellness all warrant consideration when determining the approach to each exercise session. An expert group was convened to review the published literature and develop resources to guide exercise specialists in assessing the safety of an adult with diabetes starting exercise, and indications to cease exercise, based upon glucose levels and other factors. Contraindications to people with diabetes starting or continuing exercise are (1) glucose  15.0 mmol/L with symptoms of weakness/tiredness, or with ketosis; (3) hypoglycaemic event within the previous 24 h that required assistance from another person to treat and (4) feeling unwell. To optimize diabetes and exercise safety, recommendations (stratified by pre-exercise glucose level) are provided regarding carbohydrate ingestion, glucose monitoring and medication adjustment

Glucose control using a standard versus an enhanced hybrid closed loop system: a randomized crossover study

Hybrid closed loop (HCL) insulin delivery with the Medtronic Minimed 670G system is effective and safe in people with type 1 diabetes (T1D). This study compared glucose control, closed loop (CL) exits, and alarm frequency with the standard HCL (s-HCL) versus enhanced HCL (e-HCL) Medtronic system. Pump-experienced T1D adults (n = 11; 9 female; mean [SD] age: 51 years [15 years]; HbA1c 7.5% [1.0%] or 58 mmol/mol [7.7 mmol/mol]) were assigned, in random order, s-HCL or e-HCL for 1 week each in a supervised live-in setting. e-HCL incorporated enhanced bolus reminders and iterative changes, broadening glucose and insulin delivery parameters permitting persistence in CL. For both s-HCL and e-HCL, insulin delivery was by a Medtronic pump with identical interventions (missed bolus, exercise, high-glycemic index, and high-fat meals), insulin action times, and insulin-carbohydrate ratios implemented. The primary outcome was continuous glucose monitoring time in target range. Analysis was by paired t-Test for normally distributed data and Wilcoxon-signed rank test otherwise. e-HCL resulted in significantly fewer CL alerts and exits. Time in target and mean glucose favored e-HCL but did not reach statistical significance. No episodes of severe hypoglycemia or ketoacidosis occurred. Relative to s-HCL, e-HCL use significantly decreases CL exits and alerts, and tended to improve glycemia without compromising safety, despite multiple food and exercise challenges during the study. Longer term studies at home are merited

Six months of hybrid closed-loop versus manual insulin delivery with fingerprick blood glucose monitoring in adults with type 1 diabetes: a randomized, controlled trial

Objective:\ua0To investigate glycemic and psychosocial outcomes with hybrid closed-loop (HCL) versus user-determined insulin dosing with multiple daily injections (MDI) or insulin pump (i.e., standard therapy for most adults with type 1 diabetes).Research design and methods:\ua0Adults with type 1 diabetes using MDI or insulin pump without continuous glucose monitoring (CGM) were randomized to 26 weeks of HCL (Medtronic 670G) or continuation of current therapy. The primary outcome was masked CGM time in range (TIR; 70–180 mg/dL) during the final 3 weeks.Results:\ua0Participants were randomized to HCL (n\ua0= 61) or control (n\ua0= 59). Baseline mean (SD) age was 44.2 (11.7) years, HbA1c\ua0was 7.4% (0.9%) (57 [10] mmol/mol), 53% were women, and 51% used MDI. HCL TIR increased from (baseline) 55% (13%) to (26 weeks) 70% (10%) with the control group unchanged: (baseline) 55% (12%) and (26 weeks) 55% (13%) (difference 15% [95% CI 11, 19];\ua0P\ua0< 0.0001). For HCL, HbA1c\ua0was lower (median [95% CI] difference −0.4% [−0.6, −0.2]; −4 mmol/mol [−7, −2];\ua0P\ua0< 0.0001) and diabetes-specific positive well-being was higher (difference 1.2 [95% CI 0.4, 1.9];\ua0P\ua0< 0.0048) without a deterioration in diabetes distress, perceived sleep quality, or cognition. Seventeen (9 device-related) versus 13 serious adverse events occurred in the HCL and control groups, respectively.Conclusions:\ua0In adults with type 1 diabetes, 26 weeks of HCL improved TIR, HbA1c, and their sense of satisfaction from managing their diabetes compared with those continuing with user-determined insulin dosing and self-monitoring of blood glucose. For most people living with type 1 diabetes globally, this trial demonstrates that HCL is feasible, acceptable, and advantageous