Gastric Myoelectrical Activity and Autonomic Nervous System Abnormalities in Patients with Chronic Unexplained Nausea and Vomiting and in Patients with Gastroparesis

Abstract

Background: Patients with chronic unexplained nausea and vomiting (CUNV) and Gastroparesis (GP) have similar symptoms, suggesting they share pathophysiological abnormalities along a continuum of disease.Objectives: To determine the incidence of gastric myoelectrical, accommodation dysfunction and autonomic abnormalities in patients with CUNV and GP.Methods: Outpatients with CUNV and GP who underwent standard 4-hr solid phase gastric emptying, upright tilt table test and electrogastrogram (EGG) recordings with water load satiety test (WLST) were identified from chart review. Subjects with normal emptying were in the CUNV group; those with delayed emptying were in the GP group. EGGs were recorded before and 30 minutes after the WLST and symptoms were recorded on a 100mm visual analog scale.Results: 44 patients (35 women and 9 men, ages 17-76 years) were identified: 24 had normal gastric emptying and CUNV and 20 had GP. Gastric dysrhythmias were found in 70% of CUNV and 69% of GP patients. Twenty percent of CUNV patients and 44% of GP patients ingested abnormally low volumes (< 300mL) during the WLST. Nausea increased similarly after the WLST in the subjects with CUNV and GP (Ps > 0.05). Postural orthostatic tachycardia syndrome (POTS) was diagnosed in 17% of CUNV patients and 20% of GP patients.Conclusions: Gastric myoelectrical and accommodation abnormalities and autonomic nervous system (ANS) dysfunctions frequently occur in subjects with CUNV and GP. These pathophysiological abnormalities support the idea that CUNV and GP occur along the same continuum of gastric neuromuscular dysfunction and may be targets for therapeutic approaches.