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
Abstract
BACKGROUND

Abdominal pain-predominant functional gastrointestinal disorders (AP-FGIDs) are the most common cause of recurrent abdominal pain in children. Despite its high prevalence, the underlying pathophysiology of this condition is poorly understood.

AIM

To assess the role of gastric dysmotility and autonomic nervous system dysfunction in the pathophysiology of AP-FGIDs.

METHODS

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

RESULTS

The main gastric motility parameters assessed (gastric emptying rate [45.7 vs 59.6 in controls], amplitude [48.7 vs 58.2], frequency of antral contractions [8.3 vs 9.4], and antral motility index [4.1 vs 6.4]) were significantly lower in children with AP-FGIDs (P < 0.05). The post-prandial antral dilatation at 1 min after the test meal significantly correlated with the severity of abdominal pain (P < 0.05). Assessment of autonomic functions in AP-FGID patients showed neither a significant difference compared to the control group, nor a correlation with gastric motility abnormalities (P > 0.05). The duration of pain episodes negatively correlated with the parasympathetic tone (maladaptive parasympathetic tone) (P < 0.05).

CONCLUSION

Children with AP-FGIDs have abnormal gastric motility but normal cardiovascular autonomic functions. There is no relationship between abnormal gastric motility and autonomic functions. The pathogenesis of AP-FGIDs is not related to cardiovascular autonomic dysfunction.

Keywords: Abdominal pain, Functional gastrointestinal disorders, Autonomic function, Gastric motility

Core tip: In this study, we examined the relationship between cardiovascular autonomic functions and functional abdominal pain disorders in children. We failed to demonstrate a significant difference in autonomic functions and a significant relationship between gastric motor abnormalities and autonomic functions in affected children. In this paper, we propose functional extrinsic denervation and maladaptive parasympathetic division as possible contributing factors for the impaired gastric motility and symptoms in functional abdominal pain disorders, which is demonstrated in the ‘Automatic Stomach’ model.