Assessment of symptoms, quality of life and remnant gastric activity following gastric bypass using Gastric Alimetry

BackgroundWhile most gastric bypass patients recover well, some experience long-term complications, including nausea, pain, stricture, and dumping. This study aimed to evaluate symptoms and quality of life (QoL) together with remnant stomach function using the novel Gastric Alimetry(R) system. MethodGastric bypass and conversion-to-bypass patients were recruited. The Gastric Alimetry system (Auckland, NZ) was employed, comprising a high-resolution electrode Array, and validated symptom logging App. The protocol comprised 30-minute fasting baseline, a 218kCal meal stimulus, and 4-hours of post-prandial recordings. Symptoms and QoL were evaluated using validated PAGI questionnaires. Remnant gastric electrophysiology evaluation included frequency, BMI-adjusted amplitude, and Gastric Alimetry Rhythm Index (GA-RI; reflecting pacemaker stability), with comparison to matched controls. Results38 participants were recruited with mean time from bypass 46.8 {+/-} 28.6 months. One third of patients showed moderate to severe post-prandial symptoms, with patients PAGI-SYM 28 {+/-} 19 vs controls 9 {+/-} 17; PAGI-QoL 37 {+/-} 31 vs 135 {+/-} 22 (p<0.01). Remnant gastric function was markedly degraded shown by undetectable frequencies in 84% (vs 0% in controls), and low GA-RI (0.18 {+/-} 0.08 vs 0.51 {+/-} 0.22 in controls; p<0.0001). Impaired GA-RI and amplitude were correlated with worse PAGI-SYM and PAGI-QOL scores. ConclusionOne third of post-bypass patients suffered significant upper GI symptoms with reduced QoL. The bypassed remnant stomach shows highly deranged electrophysiology, reflecting disuse degeneration. These derangements correlated with QoL, although causality was not addressed.