title: Hypoglycemia Detection and Carbohydrate Suggestion in an Artificial Pancreas.
abstract: Fear of hypoglycemia is a major concern for many patients with type 1 diabetes and affects patient decisions for use of an artificial pancreas system. We propose an alternative way for prevention of hypoglycemia by issuing predictive hypoglycemia alarms and encouraging patients to consume carbohydrates in a timely manner. The algorithm has been tested on 6 subjects (3 males and 3 females, age 24.2 ± 4.5 years, weight 79.2 ± 16.2 kg, height 172.7 ± 9.4 cm, HbA1C 7.3 ± 0.48%, duration of diabetes 209.2 ± 87.9 months) over 3-day closed-loop clinical experiments as part of a multivariable artificial pancreas control system. Over 6 three-day clinical experiments, there were only 5 real hypoglycemia episodes, of which only 1 hypoglycemia episode occurred due to being missed by the proposed algorithm. The average hypoglycemia alarms per day and per subject was 3. Average glucose value when the first alarms were triggered was recorded to be 117 ± 30.6 mg/dl. Average carbohydrate consumption per alarm was 14 ± 7.8 grams. Our results have shown that most low glucose concentrations can be predicted in advance and the glucose levels can be raised back to the desired levels by consuming an appropriate amount of carbohydrate. The proposed algorithm is able to prevent most hypoglycemic events by suggesting appropriate levels of carbohydrate consumption before the actual occurrence of hypoglycemia.
authors.affiliation: Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, IL, USA.
authors.forename: Kamuran
authors.initials: K
authors.lastname: Turksoy
authors.affiliation: Department of Pediatrics and Medicine, Section of Endocrinology, Kovler Diabetes Center, University of Chicago, Chicago, IL, USA.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Kilkus
authors.affiliation: Department of Chemical and Biological Engineering, Illinois Institute of Technology, Chicago, IL, USA.
authors.forename: Iman
authors.initials: I
authors.lastname: Hajizadeh
authors.affiliation: Department of Chemical and Biological Engineering, Illinois Institute of Technology, Chicago, IL, USA.
authors.forename: Sediqeh
authors.initials: S
authors.lastname: Samadi
authors.affiliation: Department of Chemical and Biological Engineering, Illinois Institute of Technology, Chicago, IL, USA.
authors.forename: Jianyuan
authors.initials: J
authors.lastname: Feng
authors.affiliation: Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, IL, USA.
authors.forename: Mert
authors.initials: M
authors.lastname: Sevil
authors.affiliation: Department of Electrical and Computer Engineering, Illinois Institute of Technology, Chicago, IL, USA.
authors.forename: Caterina
authors.initials: C
authors.lastname: Lazaro
authors.affiliation: Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, IL, USA.
authors.forename: Nicole
authors.initials: N
authors.lastname: Frantz
authors.affiliation: Department of Pediatrics and Medicine, Section of Endocrinology, Kovler Diabetes Center, University of Chicago, Chicago, IL, USA.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Littlejohn
authors.affiliation: Department of Biomedical Engineering, Illinois Institute of Technology, Chicago, IL, USA cinar@iit.edu.|Department of Pediatrics and Medicine, Section of Endocrinology, Kovler Diabetes Center, University of Chicago, Chicago, IL, USA.|Department of Chemical and Biological Engineering, Illinois Institute of Technology, Chicago, IL, USA.
authors.forename: Ali
authors.initials: A
authors.lastname: Cinar
mesh_terms: D000328:Adult; D000465:Algorithms; D001786:Blood Glucose / Q000032:analysis*; D056902:Clinical Alarms; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000628:therapy; D004040:Dietary Carbohydrates; D005260:Female; D006801:Humans; D007003:Hypoglycemia / Q000517:prevention & control*; D008297:Male; D019397:Pancreas, Artificial
chemical_list: D001786:Blood Glucose; D004040:Dietary Carbohydrates
keywords: artificial pancreas; carbohydrate suggestion; hypoglycemia; type 1 diabetes