Published online Jan 7, 2019. doi: 10.3748/wjg.v25.i1.95
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
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.
To assess the role of gastric dysmotility and autonomic nervous system dysfunction in the pathophysiology of AP-FGIDs.
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.
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).
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.
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.