Mucosal Nerve Fiber Density Studies May Yield Insights into the Effects of Gastric Electrical Stimulation on Treatment Outcomes

Abstract

Purpose: Debilitating nausea and vomiting frequently lead to reduced activity and quality of life in patients with gastroparesis (GP). Mucosal nerve fiber (MNF) density studies may help in characterizing Gp symptoms. Methods: Gastric mucosal tissues from 5 Gp patients (mean age 53.5 yrs; 80% Caucasian, 80% female; 1 diabetic, 2 idiopathic, 2 postsurgical Gp) and 3 age-matched controls were compared. For Gp patients, full thickness stomach biopsies, obtained at permanent stimulator implantation, were processed, and samples fixed in Zamboni's solution. Superficial MNF length density (μm/μm3) was evaluated using PGP 9.5 immunostained sections, imaged by confocal microscopy and quantified with AutoNeuron®. Results were analyzed by linear regression models using STATA 11. Gastroparesis symptom were assessed using a patient-reported, Likert-scale tool (0 to 4, none to severe). Clinical histories were studied to record duration of disease. Results: MNF density was reduced in GP, at 0.0018, compared to age-matched controls, at 0.0024 (p = 0.02). Significant associations were seen between MNF density and baseline Gp symptoms of bloating anorexia, abdominal pain, and total symptoms score (See Table). A significant association was also observed between duration of disease and reduction in MNF densities, at 6.03 [2.42, 9.64] p = 0.013.Table: Table. Associations between mucosal nerve fiber density and gastroparesis symptomsConclusion: The associations between reduced MNF density and both Gp duration and symptom severity are important findings that may improve our understanding of the natural progression of gastroparesis. The relationship between MNF density and symptom severity in particular should be explored to improve treatment and outcomes for patients with gastroparesis. Disclosure: Dr Thomas L Abell is licensor, instructor and consultyant for Medtronic Inc.