Assessment of the afferent vagal nerve in patients with gastroesophageal reflux

Background: The objective of this study was to assess the integrity of the vagal nerve afferent pathways in patients with gastroesophageal reflux disease (GERD). Methods: Seven GERD patients (4 males and 3 females, mean age 39 ± 8 years) were studied. Twelve healthy volunteers (11 males and 1 female, mean age 32 ± 8 years) were used as the control group. Cortical evoked potentials were measured. Electrical stimulation of the esophageal mucosa was performed through a custom-built device. Latencies and N2/P2 amplitude were measured. Results: Reproducible cortical evoked potentials were obtained from all subjects. The stimulation threshold for GERD patients to electrical esophageal stimulation was 5.1 ± 1.5 mA compared to 7.8 ± 2.0 mA in healthy volunteers (p <0.05). There was no difference in peak latencies or N2/P2 amplitude between GERD patients and controls. Conclusions: GERD patients have a normal vagal nerve function, but they exhibit a decreased threshold for esophageal perception. The mechanism responsible for increased esophageal sensitivity observed in GERD patients is still undetermined and warrants further study.