Optimal Parameters for Gastric Electrical Stimulation Therapy for Long-Term Symptom Control in Patients with Gastroparesis

Background: Gastric electrical stimulation (GES) therapy is indicated for the treatment of drug-refractory gastroparesis (GP). However, the long-term effects of GES therapy on GP symptom control and identification of the optimal parameters to activate this long-term efficacy have not been investigated. Methods: We conducted a retrospective cohort analysis of 57 GP patients who received GES and pyloroplasty (PP). The interrogation of the GES system and assessment of GP symptoms were conducted at the initiation of GES therapy and during follow-up visits. We determined the changes in GES parameters including voltage (V), impedance (I), and current (C). The outcome was total symptom score (TSS), which was measured by self-reported GP symptoms. Results: The mean age of patients was 44 (±14) years, and 72% were females. The etiology for GP was diabetes mellitus in 72% and idiopathic in 28%. The median duration of GES follow-up was 47 months (range 5–73) A significant decrease was found in individual symptom scores and the TSS (−10.8; 95%CI: −12.6, −9.08) compared to baseline scores (p < 0.0001). During follow-up, readings for I (515 vs. 598 Ω), V (3.3 vs. 4.8 V), and C (6.5 vs. 8.4 mA) significantly increased (p ≤ 0.0001 for all parameters). Higher GES settings were associated with lower TSS in the adjusted analysis (RC, −1.97; 95%CI: −3.81, −0.12, p = 0.037). Conclusions: these findings suggest that adjusting GES parameters over time based on optimizing symptom improvement should be incorporated into the long-term care of patients receiving gastric neurostimulation therapy.