Discussion
comorbidity, abscess, hypoglycemia, infection, end-stage renal failure, diabetes
SIDE EFFECT, DISEASE, DIABETIC FOOT, ABSCESS, HYPOGLYCEMIA, INFECTION, ADVERSE EVENT, END-STAGE RENAL FAILURE, TYPE 2 DIABETES, SEQUELAE, DIABETES
The present study shows that fully closed-loop insulin delivery is a safe and effective approach to improve glycemic control in people with type 2 diabetes during 8 weeks of use in the outpatient setting. The closed-loop system improved the proportion of time spent in target glucose range by 35 percentage points (an additional 8 h per day), and reduced mean glucose, compared with standard insulin therapy, without increasing the time spent in hypoglycemia (Table The results of this study build on evidence from a feasibility study evaluating fully closed-loop therapy in people with type 2 diabetes and end-stage renal failure on dialysisThe proportion of time spent in target glucose range was higher in this study than in the previous study involving people on dialysis (66% versus 57%, respectively)A major contributor to the clinical inertia in the escalation of insulin therapy among healthcare professionals, and a feared side effect of insulin among people with type 2 diabetes, is the risk of hypoglycemiaThe degree of comorbidity burden in our study population is reflected in the number of nonstudy-related SAEs reported during the study. These were hospital admissions for treatment of comorbidities (diabetic foot disease) or infection. One severe adverse event was related to study procedures and occurred during the closed-loop therapy period (an abscess at the pump cannula site requiring hospital admission for incision and drainage with no long-term sequelae). Closed-loop therapy was continued provided that the participant was able to manage the system themselves and the treating healthcare professionals were satisfied that this was clinically appropriate.Training and maintenance of study devices by participants was acceptable. One participant withdrew because of difficulty managing the devices, whereas all other participants were able to manage the devices independently and reported a high degree of satisfaction while using the closed-loop system. All participants reported that they were happy to have their glucose levels controlled automatically by the system, and 89% reported that they spent less time managing their diabetes overall. Feedback from users highlighted the elimination of the need for injections or finger-prick testing, and increased confidence in managing blood glucose as key benefits (Supplementary Table The strengths of this study include its randomized crossover design and the inclusion of a wider population with type 2 diabetes self-managing the devices in an outpatient setting, increasing the scope for uptake of this technology. The use of a fully closed-loop system obviates the need for ongoing healthcare professional input with optimization and support following initial training on the devices.The limitations of the study are that study participants were recruited from a single center and one general practice, and the group was not ethnically diverse, with only one participant not of white ethnicity. Although the present study demonstrated glycemic benefits over the 8-week intervention period, the results should not be generalized beyond this period. The washout period of 2–4 weeks is short for measuring HbA1c. We also did not collect data on the use of boost and ease-off functionality during the closed-loop therapy period. There were a relatively large number of protocol deviations (Supplementary Table In conclusion, this study suggests that fully closed-loop insulin delivery is a safe and efficacious approach to manage type 2 diabetes in adults. Larger randomized controlled trials with diverse populations and longer follow-up are required to ensure generalizability across a wider target population and to determine whether it is a cost-effective approach that provides sustained benefits for people with type 2 diabetes requiring insulin therapy.