The Atrophy of the Vagus Nerve Correlated With Gastrointestinal Non-Motor Symptoms Scores, in Parkinson’s Disease: A Sonography Research Study

Abstract

Objective: To investigate the vagus nerve (VN) dimensional changes with Parkinson’s disease (PD), compared with healthy subjects. Additionally, it is important to investigate whether there is any relationships between these changes and patient’s motor and non-motor symptoms (NMS) of PD. Materials and Methods: A cohort of 43 patients with PD formed a group that was compared with 44 patients without PD, denoted as the healthy subject (HS) group. The diameter and areas of VN of study groups were measured using ultrasonography (US). The study groups were further divided into <65 and ≥65 subgroups, to evaluate the possible effect of age on the VN and evaluated relationships of VN dimensions, between subgroups. In the PD group, a correlational analysis was conducted between the diameter and area of the VN and the motor and NMS scores. Results: There was statistically significant difference in right ( P = .002) and left VN diameters ( P = .007) and in right ( P = .001) and left VN areas ( P = .007), between study groups. There was no significant difference in right and left VN diameters and the right and left VN areas, between subgroups. There was moderately negative correlation between gastrointestinal NMS scores and right VN area ( r = −0.499, P = .002), left VN area ( r = −0.499, P = .002), right VN diameter ( r = −0.378, P = .023), left VN diameter ( r = −0.385, P = .021), respectively. Conclusion: The US demonstrated that VN dimensions may possibly reduce in those patients affected by PD. In this cohort, it appears that an increase in gastrointestinal NMS scores may be explained by atrophy of the VN.