24/7 Closed-loop in Older Subjects With Type 1 Diabetes

Inclusion Criteria: 1. Age 60 years and above 2. Type 1 diabetes as defined by WHO for at least 1 year or confirmed C-peptide negative 3. On insulin pump for at least 3 months with good knowledge of insulin self-adjustment 4. Treated with one of the U-100 rapid acting insulin analogues only (insulin Aspart, Lispro, Faster insulin Aspart but not Glulisine) 5. Willing to perform regular capillary blood glucose monitoring 6. HbA1c ≤ 10% (86 mmol/mmol) based on analysis from central laboratory or equivalent 7. Literate in English 8. Having a care partner who is aware of the subject's location and is trained to administer intramuscular glucagon and able to seek emergency assistance 9. Willing to wear closed-loop system at home and at work place 10. Willing to follow study specific instructions 11. Willing to upload pump and CGM data at regular intervals 12. Has access to WiFi Exclusion Criteria: 1. Non-type 1 diabetes mellitus 2. Use of a closed-loop system within the last 30 days 3. Any other physical or psychological disease or condition likely to interfere with the normal conduct of the study and interpretation of the study results 4. Use of any glucose-lowering agent (such as Pramlintide, Metformin, GLP-1 analogs) in the 3 months prior to enrolment or any use of SGLT2 inhibitors 5. Untreated coeliac disease, adrenal insufficiency or hypothyroidism 6. Known or suspected allergy against insulin 7. More than one episodes of severe hypoglycaemia as defined by American Diabetes Association in preceding 6 months 8. Random C-peptide \> 200pmol/l with concomitant plasma glucose \>4 mmol/l (72 mg/dl) 9. Lack of reliable telephone facility for contact 10. Total daily insulin dose \>/= 2 IU/kg/day 11. Total daily insulin dose \< 15 IU/day 12. Severe visual impairment 13. Severe hearing impairment 14. Medically documented allergy towards the adhesive (glue) of plasters or unable to tolerate tape adhesive in the area of sensor placement 15. Serious skin diseases (e.g. psoriasis vulgaris, bacterial skin diseases) located at places of the body, which could potentially be used for localisation of the glucose sensor) 16. Subject is currently abusing illicit drugs 17. Subject is currently abusing prescription drugs 18. Subject is currently abusing alcohol 19. Subject has elective surgery planned that requires general anaesthesia during the course of the study 20. Subject is a shift worker with working hours between 10pm and 8am 21. Subject has a sickle cell disease, haemoglobinopathy; or has received red blood cell transfusion or erythropoietin within 3 months prior to time of screening 22. Subject plans to receive red blood cell transfusion or erythropoietin over the course of study participation 23. Subject diagnosed with current eating disorder such as anorexia or bulimia 24. Subject plans to use significant quantity of herbal preparations (use of over the counter herbal preparation for 30 consecutive days or longer period during the study) or significant quantity of vitamin supplements (four times the recommended daily allowance used for 30 consecutive days or longer period during the study) known to affect glucose metabolism and/or blood glucose levels during the course of their participation in the study 25. Subject not proficient in English (UK), or German (Austria) Additional exclusion criteria specific for Austria 1. Positive results on urine drug screen (amphetamines/metamphetamines, barbiturates, benzodiazepines, cannabinoids, cocaine, opiates). 2. Positive alcohol breath test. 3. Positive reaction to any of the following tests: hepatitis B surface (HBs) antigen, anti-hepatitis C virus (anti-HCV) antibodies, anti-human immunodeficiency virus (HIV) 1 antibodies, anti-HIV2 antibodies.