Case Control Study
Copyright ©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Jan 7, 2019; 25(1): 95-106
Published online Jan 7, 2019. doi: 10.3748/wjg.v25.i1.95
Autonomic functions and gastric motility in children with functional abdominal pain disorders
Amaranath Karunanayake, Shaman Rajindrajith, Hitanadura Asita de Silva, Sampath Gunawardena, Niranga Manjuri Devanarayana
Amaranath Karunanayake, Sampath Gunawardena, Department of Physiology, Faculty of Medicine, University of Ruhuna, Karapitiya, Galle 80000, Sri Lanka
Shaman Rajindrajith, Department of Paediatrics, Faculty of Medicine, University of Kelaniya, Ragama 11010, Sri Lanka
Hitanadura Asita de Silva, Department of Pharmacology, Faculty of Medicine, University of Kelaniya, Ragama 11010, Sri Lanka
Niranga Manjuri Devanarayana, Department of Physiology, Faculty of Medicine, University of Kelaniya, Ragama 11010, Sri Lanka
Author contributions: Karunanayake A contributed to the study design, data collection by performing autonomic function tests, analysis and interpretation of data and wrote the initial draft; Devanarayana NM conceptualized the study and contributed to the study design, data collection by conducting motility studies, interpretation of data and revised the manuscript; de Silva HA and Gunawardena S contributed to study design; Rajindrajith S helped design the study and contributed to revisions to the final manuscript.
Supported by a Research Grant from the University of Kelaniya, Sri Lanka, No. RP/03/04/03/01/2013.
Institutional review board statement: This study protocol was approved by the Ethics Review Committee, Faculty of Medicine, University of Kelaniya, Sri Lanka.
Informed consent statement: Written informed consent was obtained from a parent of all recruited participants.
Conflict-of-interest statement: No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article.
Data sharing statement: Technical appendix, statistical code and dataset available from the corresponding author at niranga@kln.ac.lk.
STROBE statement: Authors have read the STROBE Statement-checklist of items, and the manuscript was prepared and revised according to the STROBE Statement-checklist of items.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Corresponding author: Niranga Manjuri Devanarayana, MBSS, MD, PhD, Professor, Department of Physiology, Faculty of Medicine, University of Kelaniya, Thalagolla Road, Ragama 11010, Sri Lanka. niranga@kln.ac.lk
Telephone: +94-11-2961150 Fax: +94-11-2958337
Received: September 12, 2018
Peer-review started: September 12, 2018
First decision: October 24, 2018
Revised: December 1, 2018
Accepted: December 13, 2018
Article in press: December 13, 2018
Published online: January 7, 2019
ARTICLE HIGHLIGHTS
Research background

Abdominal pain-predominant functional gastrointestinal disorders (AP-FGIDs) are a common clinical problem in paediatric practice across the globe, with an estimated prevalence of 13.5%. Although thought to be benign in nature, as a group they are known to associate with poor health-related quality of life and high healthcare burden.

Research motivation

The pathophysiology of AP-FGIDs is not clearly understood. Previous studies have shown abnormalities in gastroduodenal motility, such as delayed gastric emptying, impaired antral motility, and impaired gastric accommodation as potential pathophysiological mechanisms in children. Studies among adults have found autonomic dysfunction in patients with IBS. However, the association between autonomic dysfunction and gastric motility in children with AP-FGIDs had not been previously evaluated.

Research objectives

The main objective of our study was to assess the autonomic functions in children with AP-FGIDs and their relationship to gastric motor functions.

Research methods

One hundred children fulfilling Rome III criteria for AP-FGIDs and 50 healthy controls aged 5 to 12 years were recruited for the study. All patients were thoroughly investigated to rule out underlying organic disorders. Gastric motility and cardiovascular autonomic functions were assessed using validated, non-invasive techniques.

Research results

Gastric emptying rate, amplitude of antral contractions, and antral motility index were significantly lower in children with AP-FGIDs. Autonomic functions, including blood pressure and heart rate responses to standing from lying down position, heart rate response to deep breathing, and Valsalva test, showed no difference between children with AP-FGIDs and controls. These parameters did not show any correlation with gastric motor functions. However, the duration of pain episodes negatively correlated with the parasympathetic tone.

Research conclusions

Although children with AP-FGIDs have abnormal gastric motility parameters, their cardiovascular autonomic functions are normal. In addition, there is no correlation between autonomic functions and gastric motility. Our findings indicate that the autonomic nervous system is not chronically abnormal in patients with AP-FGIDs. Based on currently available evidence, we propose maladaptive parasympathetic flow and an automated stomach model as a potential pathophysiological mechanism for AP-FGIDs.