Comparing Longitudinal Overall and Individual Symptom Outcomes on Neuromodulator versus Prokinetic Drugs in Patients With Symptoms Suspicious for Gastroparesis but With Non—Delayed Gastric Emptying

Abstract

Introduction: Most patients with suspected gastroparesis do not have delayed gastric emptying. These patients are often treated with prokinetic agents but neuromodulator drugs are also given to reduce symptoms. Relative benefits of each drug class are unknown. In a multicenter study, we hypothesized that patients with suspected gastroparesis with non—delayed gastric emptying on scintigraphy (GES) or wireless motility capsules (WMC) show differential symptom benefits after prescribing neuromodulator vs. prokinetic medications. Methods: Management plans were devised for 150 patients with suspected gastroparesis. Investigators reviewed concurrent GES and WMC results and recommended therapy changes for those patients with non—delayed gastric emptying by GES (<10% 4 hr retention) or WMC (emptying <5 hr). Symptom (GCSI/PAGI—SYM) scores at baseline and 6 months were related to neuromodulator and prokinetic recommendations.1201_A Figure 1. Overall GCSI Reductions on Neuromodulators and Prokinetics in Patients with Non—Delayed Gastric Emptying1201_B Figure 2. Improvements in Individual Symptoms on Neuromodulators and Prokinetics in Patients with Non—Delayed Gastric EmptyingResults: 76% and 65% of patients had non—delayed gastric emptying by GES and WMC. 64 were prescribed neuromodulators including antidepressants—42 (mirtazapine/tricyclics—35), gabapentin—10, buspirone—9, and other—5. 49 received prokinetics including dopamine receptor antagonists (DRAs) (metoclopramide/domperidone—34) and pure prokinetics (macrolides, pyridostigmine, botulinum toxin—22). At 6 months, neuromodulators and prokinetics reduced overall GCSI scores similarly (Table). DRAs but not pure prokinetics reduced overall scores. Of neuromodulators, antidepressants and buspirone but not gabapentin reduced overall GCSIs. Individual symptoms improved with both drug classes; N/V improved less than other symptoms on neuromodulators but not prokinetics (Figure). DRAs but not pure prokinetics reduced all individual symptoms (P<0.05). Antidepressants but not gabapentin reduced all individual symptoms with GES vs. fullness and pain with WMC (P<0.05). Buspirone lowered fullness and bloating (P<0.05). Conclusion: Neuromodulator and prokinetic drugs are associated with differential benefits in patients with suspected gastroparesis with non—delayed gastric emptying on GES and WMC testing. Both drug classes are associated with improved symptoms, but lower N/V responses on neuromodulators suggest they are less effective antiemetics than prokinetics. Dopamine antagonists are associated with better responses than pure prokinetics. Antidepressants and buspirone relate to better responses than gabapentin. Our results offer unique insight into treating this large, distinct patient group.