title: Simulation environment to evaluate closed-loop insulin delivery systems in type 1 diabetes.
abstract: BACKGROUND
  Closed-loop insulin delivery systems linking subcutaneous insulin infusion to real-time continuous glucose monitoring need to be evaluated in humans, but progress can be accelerated with the use of in silico testing. We present a simulation environment designed to support the development and testing of closed-loop insulin delivery systems in type 1 diabetes mellitus (T1DM).
  
  
  METHODS
  The principal components of the simulation environment include a mathematical model of glucose regulation representing a virtual population with T1DM, the glucose measurement model, and the insulin delivery model. The simulation environment is highly flexible. The user can specify an experimental protocol, define a population of virtual subjects, choose glucose measurement and insulin delivery models, and specify outcome measures. The environment provides graphical as well as numerical outputs to enable a comprehensive analysis of in silico study results. The simulation environment is validated by comparing its predictions against a clinical study evaluating overnight closed-loop insulin delivery in young people with T1DM using a model predictive controller.
  
  
  RESULTS
  The simulation model of glucose regulation is described, and population values of 18 synthetic subjects are provided. The validation study demonstrated that the simulation environment was able to reproduce the population results of the clinical study conducted in young people with T1DM.
  
  
  CONCLUSIONS
  Closed-loop trials in humans should be preceded and concurrently guided by highly efficient and resource-saving computer-based simulations. We demonstrate validity of population-based predictions obtained with our simulation environment.
authors.affiliation: Cambridge University Metabolic Research Laboratories, Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge, UK. mew37@cam.ac.uk
authors.forename: Malgorzata E
authors.initials: ME
authors.lastname: Wilinska
authors.forename: Ludovic J
authors.initials: LJ
authors.lastname: Chassin
authors.forename: Carlo L
authors.initials: CL
authors.lastname: Acerini
authors.forename: Janet M
authors.initials: JM
authors.lastname: Allen
authors.forename: David B
authors.initials: DB
authors.lastname: Dunger
authors.forename: Roman
authors.initials: R
authors.lastname: Hovorka
mesh_terms: D000293:Adolescent; D000465:Algorithms; D001786:Blood Glucose / Q000032:analysis / Q000378:metabolism; D015190:Blood Glucose Self-Monitoring / Q000295:instrumentation* / Q000379:methods; D002648:Child; D003198:Computer Simulation; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000188:drug therapy* / Q000378:metabolism; D004777:Environment; D005260:Female; D006801:Humans; D015918:Infusion Pumps, Implantable; D055104:Infusions, Subcutaneous; D007328:Insulin / Q000008:administration & dosage*; D007332:Insulin Infusion Systems; D008297:Male; D008954:Models, Biological; D008962:Models, Theoretical; D018670:Monitoring, Ambulatory / Q000295:instrumentation / Q000379:methods
chemical_list: D001786:Blood Glucose; D007328:Insulin