Meta-analysis of overnight closed-loop randomized studies in children and adults with type 1 diabetes: the Cambridge cohort.
OBJECTIVE
We reviewed the safety and efficacy of overnight closed-loop insulin delivery compared with conventional continuous subcutaneous insulin infusion (CSII) in two distinct age groups with type 1 diabetes mellitus (T1DM), young people aged 5 to 18 years and adults, combining data of previously published randomized studies.


METHODS
We evaluated four randomized crossover studies in 17 children and adolescents [13.4 ± 3.6 years; mean ± standard deviation (SD)] and 24 adults (37.5 ± 9.1 years) on 45 closed-loop (intervention) and 45 CSII (control) visits. Each subject attended for two overnight study visits, using either closed-loop or conventional pump therapy, in random order. In each age group, studies were designed to mimic realistic likely scenarios. In the children and adolescent studies, closed loop was used following a standard evening meal and following 40 min of moderate-intensity exercise. In the adult studies, closed loop was commenced following a 60 g carbohydrate meal or a 100 g carbohydrate meal accompanied by alcohol. The primary outcome measure was time for which plasma glucose was within target range (3.91-8.0 mmol/liter).


RESULTS
Overnight closed loop increased the time in target plasma glucose in both young (from 40% to 60%, p = .002) and adults (from 50% to 76%, p < .001) compared with conventional CSII. Combined analysis showed an increase from 43% to 71% with closed loop (p < .001). Additionally, closed loop reduced the time spent below 3.91 mmol/liter and above 8.0 mmol/liter, from 4.1% to 2.1% (p = .01) and 33% to 20% (p = .03), respectively. Glycemic variability, as measured by the SD of plasma glucose, was lower during closed loop compared with CSII (1.5 versus 2.1 mmol/liter, p = .007).


CONCLUSIONS
Overnight closed loop may improve glycemic control and reduce nocturnal hypoglycemia in both young people and adults with T1DM.
Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom.
Kavita
K
Kumareswaran
Daniela
D
Elleri
Janet M
JM
Allen
Julie
J
Harris
Dongyuan
D
Xing
Craig
C
Kollman
Marianna
M
Nodale
Helen R
HR
Murphy
Stephanie A
SA
Amiel
Simon R
SR
Heller
Malgorzata E
ME
Wilinska
Carlo L
CL
Acerini
Mark L
ML
Evans
David B
DB
Dunger
Roman
R
Hovorka
D000293:Adolescent; D000328:Adult; D000465:Algorithms; D001786:Blood Glucose / Q000032:analysis; D002648:Child; D015331:Cohort Studies; D018592:Cross-Over Studies; D003922:Diabetes Mellitus, Type 1 / Q000188:drug therapy*; D005260:Female; D006801:Humans; D007004:Hypoglycemic Agents / Q000008:administration & dosage*; D007328:Insulin / Q000008:administration & dosage*; D007332:Insulin Infusion Systems; D008297:Male; D016032:Randomized Controlled Trials as Topic
D001786:Blood Glucose; D007004:Hypoglycemic Agents; D007328:Insulin