title: Study of Glycemic Variability Through Time Series Analyses (Detrended Fluctuation Analysis and Poincaré Plot) in Children and Adolescents with Type 1 Diabetes.
abstract: Time series analysis provides information on blood glucose dynamics that is unattainable with conventional glycemic variability (GV) indices. To date, no studies have been published on these parameters in pediatric patients with type 1 diabetes. Our aim is to evaluate the relationship between time series analysis and conventional GV indices, and glycosylated hemoglobin (HbA1c) levels.
  
  
  
  This is a transversal study of 41 children and adolescents with type 1 diabetes. Glucose monitoring was carried out continuously for 72 h to study the following GV indices: standard deviation (SD) of glucose levels (mg/dL), coefficient of variation (%), interquartile range (IQR; mg/dL), mean amplitude of the largest glycemic excursions (MAGE), and continuous overlapping net glycemic action (CONGA). The time series analysis was conducted by means of detrended fluctuation analysis (DFA) and Poincaré plot.
  
  
  
  Time series parameters (DFA alpha coefficient and elements of the ellipse of the Poincaré plot) correlated well with the more conventional GV indices. Patients were grouped according to the terciles of these indices, to the terciles of eccentricity (1: 12.56-16.98, 2: 16.99-21.91, 3: 21.92-41.03), and to the value of the DFA alpha coefficient (> or ≤1.5). No differences were observed in the HbA1c of patients grouped by GV index criteria; however, significant differences were found in patients grouped by alpha coefficient and eccentricity, not only in terms of HbA1c, but also in SD glucose, IQR, and CONGA index.
  
  
  
  The loss of complexity in glycemic homeostasis is accompanied by an increase in variability.
authors.affiliation: 1 Pediatria, Hospital de Sagunto , Sagunto, Spain .
authors.forename: Leonor
authors.initials: L
authors.lastname: García Maset
authors.affiliation: 2 Endocrinología Pediátrica, Hospital de Sagunto , Sagunto, Spain .
authors.forename: Lidia Blasco
authors.initials: LB
authors.lastname: González
authors.affiliation: 3 Bioquímica Clínica y Microbiologia, Hospital de Sagunto , Sagunto, Spain .
authors.forename: Gonzalo Llop
authors.initials: GL
authors.lastname: Furquet
authors.affiliation: 4 Estadística e Investigación Operativa, Universidad de Valencia , Valencia, Spain .
authors.forename: Francisco Montes
authors.initials: FM
authors.lastname: Suay
authors.affiliation: 5 Facultad de Medicina y Odontología, Universidad de Valencia , Valencia, Spain .
authors.forename: Roberto Hernández
authors.initials: RH
authors.lastname: Marco
mesh_terms: D000293:Adolescent; D001786:Blood Glucose / Q000032:analysis*; D002648:Child; D003430:Cross-Sectional Studies; D003922:Diabetes Mellitus, Type 1 / Q000097:blood*; D005260:Female; D006442:Glycated Hemoglobin; D006801:Humans; D007003:Hypoglycemia / Q000097:blood; D008297:Male; D018670:Monitoring, Ambulatory; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin
keywords: Continuous interstitial glucose monitoring; Detrended fluctuation analysis; Glycemic variability; Poincaré plot; Type 1 diabetes