title: Randomized trial of a dual-hormone artificial pancreas with dosing adjustment during exercise compared with no adjustment and sensor-augmented pump therapy.
abstract: To test whether adjusting insulin and glucagon in response to exercise within a dual-hormone artificial pancreas (AP) reduces exercise-related hypoglycaemia.
  
  
  
  In random order, 21 adults with type 1 diabetes (T1D) underwent three 22-hour experimental sessions: AP with exercise dosing adjustment (APX); AP with no exercise dosing adjustment (APN); and sensor-augmented pump (SAP) therapy. After an overnight stay and 2 hours after breakfast, participants exercised for 45 minutes at 60% of their maximum heart rate, with no snack given before exercise. During APX, insulin was decreased and glucagon was increased at exercise onset, while during SAP therapy, subjects could adjust dosing before exercise. The two primary outcomes were percentage of time spent in hypoglycaemia (<3.9 mmol/L) and percentage of time spent in euglycaemia (3.9-10 mmol/L) from the start of exercise to the end of the study.
  
  
  
  The mean (95% confidence interval) times spent in hypoglycaemia (<3.9 mmol/L) after the start of exercise were 0.3% (-0.1, 0.7) for APX, 3.1% (0.8, 5.3) for APN, and 0.8% (0.1, 1.4) for SAP therapy. There was an absolute difference of 2.8% less time spent in hypoglycaemia for APX versus APN (p = .001) and 0.5% less time spent in hypoglycaemia for APX versus SAP therapy (p = .16). Mean time spent in euglycaemia was similar across the different sessions.
  
  
  
  Adjusting insulin and glucagon delivery at exercise onset within a dual-hormone AP significantly reduces hypoglycaemia compared with no adjustment and performs similarly to SAP therapy when insulin is adjusted before exercise.
authors.affiliation: Department of Biomedical Engineering, Oregon Health and Science University, Portland. jacobsp@ohsu.edu.
authors.forename: P G
authors.initials: PG
authors.lastname: Jacobs
authors.affiliation: Department of Medicine, Division of Endocrinology, Harold Schnitzer Diabetes Health Center, Oregon Health and Science University, Portland.
authors.forename: J
authors.initials: J
authors.lastname: El Youssef
authors.affiliation: Department of Biomedical Engineering, Oregon Health and Science University, Portland.
authors.forename: R
authors.initials: R
authors.lastname: Reddy
authors.affiliation: Department of Biomedical Engineering, Oregon Health and Science University, Portland.
authors.forename: N
authors.initials: N
authors.lastname: Resalat
authors.affiliation: Department of Medicine, Division of Endocrinology, Harold Schnitzer Diabetes Health Center, Oregon Health and Science University, Portland.
authors.forename: D
authors.initials: D
authors.lastname: Branigan
authors.affiliation: Department of Biomedical Engineering, Oregon Health and Science University, Portland.
authors.forename: J
authors.initials: J
authors.lastname: Condon
authors.affiliation: Department of Biomedical Engineering, Oregon Health and Science University, Portland.
authors.forename: N
authors.initials: N
authors.lastname: Preiser
authors.affiliation: Oregon Clinical and Translational Research Institute Biostatistics and Design Program, Oregon Health and Science University, Portland.
authors.forename: K
authors.initials: K
authors.lastname: Ramsey
authors.affiliation: Department of Medicine, Division of Endocrinology, Harold Schnitzer Diabetes Health Center, Oregon Health and Science University, Portland.
authors.forename: M
authors.initials: M
authors.lastname: Jones
authors.affiliation: Department of Medicine, Division of Endocrinology, Harold Schnitzer Diabetes Health Center, Oregon Health and Science University, Portland.
authors.forename: C
authors.initials: C
authors.lastname: Edwards
authors.affiliation: Department of Medicine, Division of Health Promotion and Sports Medicine, Human Performance Laboratory, Oregon Health and Science University, Portland.
authors.forename: K
authors.initials: K
authors.lastname: Kuehl
authors.affiliation: Department of Biomedical Engineering, Oregon Health and Science University, Portland.
authors.forename: J
authors.initials: J
authors.lastname: Leitschuh
authors.affiliation: Department of Biomedical Engineering, Oregon Health and Science University, Portland.
authors.forename: U
authors.initials: U
authors.lastname: Rajhbeharrysingh
authors.affiliation: Department of Medicine, Division of Endocrinology, Harold Schnitzer Diabetes Health Center, Oregon Health and Science University, Portland.
authors.forename: J R
authors.initials: JR
authors.lastname: Castle
mesh_terms: D000293:Adolescent; D000328:Adult; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D001786:Blood Glucose / Q000187:drug effects / Q000378:metabolism; D018592:Cross-Over Studies; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000188:drug therapy*; D004305:Dose-Response Relationship, Drug; D015444:Exercise / Q000502:physiology*; D005260:Female; D005934:Glucagon / Q000008:administration & dosage* / Q000009:adverse effects; D006801:Humans; D007003:Hypoglycemia / Q000139:chemically induced / Q000517:prevention & control; D007004:Hypoglycemic Agents / Q000008:administration & dosage* / Q000009:adverse effects; D007328:Insulin / Q000008:administration & dosage* / Q000009:adverse effects; D007332:Insulin Infusion Systems; D008297:Male; D008875:Middle Aged; D019397:Pancreas, Artificial / Q000009:adverse effects; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D007004:Hypoglycemic Agents; D007328:Insulin; D005934:Glucagon
keywords: artificial pancreas; continuous glucose monitoring (CGM); exercise; glucagon; hypoglycaemia; insulin delivery; type 1 diabetes