title: Gastroesophageal reflux is not associated with short-term variability of parasympathetic activity in children.
abstract: OBJECTIVE
  A lower parasympathetic activity was described in patients with the gastroesophageal reflux disease. We aimed to determine whether gastroesophageal reflux (GER) episodes are associated with a short-term parasympathetic tone variability in children.
  
  
  METHODS
  In order to address this question we performed simultaneous 24-h esophageal multichannel intraluminal impedance-pH and electrocardiographic monitoring in 16 children (age range 6-18 years), including 8 with asthma and 2 with gastroesophageal reflux disease. After describing duration, height, and acidity of 483 GER episodes we also measured parasympathetic-related heart rate variability parameters in 4 time periods: preceding, containing, following GER, and in-between GERs (control). High frequency (HF) power and root-mean square differences of successive R-R intervals (r-MSSD) were assessed in 2.5-min and 1-min periods, respectively.
  
  
  RESULTS
  We did not identify the searched short-term parasympathetic tone changes.
  
  
  CONCLUSIONS
  In conclusion, GER episodes and their characteristics were not associated with short-term variability of parasympathetic activity in children.
authors.affiliation: Department of Pediatric Gastroenterology and Metabolic Diseases, Poznan University of Medical Sciences, Poznan, Poland. Electronic address: jan.nowak@ump.edu.pl.
authors.forename: Jan Krzysztof
authors.initials: JK
authors.lastname: Nowak
authors.affiliation: Department of Pediatric Cardiology, Nephrology and Hypertension of the Developmental Age, Poznan University of Medical Sciences, Poznan, Poland.
authors.forename: Agata
authors.initials: A
authors.lastname: Łaźniak
authors.affiliation: Department of Pediatric Gastroenterology and Metabolic Diseases, Poznan University of Medical Sciences, Poznan, Poland.
authors.forename: Aleksandra
authors.initials: A
authors.lastname: Lisowska
authors.affiliation: Department of Pediatric Pneumonology, Allergology and Clinical Immunology, Poznan University of Medical Sciences, Poznan, Poland.
authors.forename: Zdzisława
authors.initials: Z
authors.lastname: Kycler
authors.affiliation: Department of Pediatric Cardiology, Nephrology and Hypertension of the Developmental Age, Poznan University of Medical Sciences, Poznan, Poland.
authors.forename: Waldemar
authors.initials: W
authors.lastname: Bobkowski
authors.affiliation: Department of Pediatric Gastroenterology and Metabolic Diseases, Poznan University of Medical Sciences, Poznan, Poland.
authors.forename: Jarosław
authors.initials: J
authors.lastname: Walkowiak
mesh_terms: D000293:Adolescent; D002648:Child; D050782:Esophageal pH Monitoring; D005260:Female; D005500:Follow-Up Studies; D005745:Gastric Acidity Determination; D005764:Gastroesophageal Reflux / Q000503:physiopathology*; D006801:Humans; D008297:Male; D010275:Parasympathetic Nervous System / Q000503:physiopathology*; D011379:Prognosis
keywords: Asthma; Autonomic nervous system; Gastroesophageal reflux disease; Heart rate variability; Impedance