Gastric Electrical Stimulation Improves Severe Abdominal Pain in Patients With Diabetic and Idiopathic Gastroparesis Over a 3-Year Period

Abstract

Introduction: Abdominal pain is present in patients with gastroparesis (GP) to a variable degree (21-89%). It's mechanism is not well understood as pain severity does not correlate with the degree of gastric stasis. Gastric electrical stimulation (GES) improves nausea and vomiting in GP but it does not consistently improve gastric emptying time. The aim of the study was: 1. To determine if the prevalence of abdominal pain is different in patients with diabetic vs. idiopathic GP. 2. To compare the long term clinical response of GES among GP patients with chronic abdominal pain. Methods: We retrospectively reviewed medical records of 53 patients with severe GP who underwent GES implantation between March 2007 and March 2013. Upper GI symptoms were assessed by a modified Gastroparesis Cardinal Symptom Index (GCSI) score on a scale of 0-4 that inquired about 3 subscales; vomiting and nausea, early satiety and post-prandial fullness, and bloating. Abdominal pain and epigastric burning were assessed, at baseline, 1, 2 and 3 years after GES implant. Patients were divided according to pain score at baseline; severe abdominal pain (score ≥ 2.50) and mild abdominal pain (score < 2.50) Results: 53 patients (diabetic=33, idiopathic= 20), mean age of 42 years had GES for more than 3 years. 33/53 (62%) scored severe abdominal pain; 20/53 (38%) mild abdominal pain. In idiopathic GP the mean pain score was 3.13. In diabetics the mean pain score was 2.50; (p=0.18). In patients with severe abdominal pain, the overall GCSI, (including subscores of vomiting, early satiety, bloating, post-prandial fullness), and abdominal pain and epigastric burning improved significantly at 1 year (p=0.0004, p=0.01, p=0.00006, p=0.005, p=0.04, p=0.0006, p=0.00003 and p=0.001, respectively). This was sustained at 2 and 3 years after GES (Table 1). In patients with mild abdominal pain, the pain and epigastric burning improved significantly after 2 years, (p=0.009 and p=0.04, respectively). In both groups the need for prokinetic medications decreased consistently at 1, 2 and 3 years from baseline. The use of narcotic and non narcotic analgesics did not change significantly over time.Table 1: Symptom severity in patients with severe gastroparesisConclusion: GES therapy significantly improved both severe and mild abdominal pain in patients with severe GP regardless of etiology. This improvement was sustained over 3 years.The prevalence of abdominal pain did not differ among patients with severe diabetic or idiopathic GP in our population.