Effects of cutaneous gastric electrical stimulation on gastric emptying and postprandial satiety and fullness in lean and obese subjects

Goals: The aim of this study was to investigate the therapeutic potential of cutaneous gastric electrical stimulation (CGES) at a tachygastrial frequency for obesity. Background: Implantable gastric electrical stimulator has been proposed for the treatment of obesity and it has recently been reported that the gastric electrical stimulation at a tachygastrial frequency inhibits gastric motility. STUDY Methods: Ten lean and 10 obese healthy volunteers were studied in 3 randomized sessions: no CGES, CGES at the physiologic frequency (3cycles/min), and CGES at tachygastrial frequency (12cycles/min). Electrical stimulation was performed using sinusoidal waves. The protocol included the following sequence: 20-minute baseline, 30-minute CGES, 30-minute recording without CGES, 30-minute CGES, ingestion of a 500kcal liquid meal, and 30-minute CGES. Gastric slow waves were recorded using cutaneous electrogastrography during the periods without CGES. Gastric emptying was assessed by ultrasound. Dyspeptic symptoms were recorded. Results: (1) The half-time of gastric emptying was longer with CGES at the tachygastrial frequency than CGES at the physiologic frequency in both lean subjects (75.0±16.5min vs. 41.0±8.7min, P<0.01) and obese subjects (64.1±13.3min vs. 32.7±5.0min, P<0.01). (2) Postprandial dyspeptic symptom score (mainly satiety and fullness) was significantly higher with CGES at the tachygastrial frequency than CGES at the physiologic frequency in both lean (3.2±1.47 vs. 1.7±0.94, P<0.01) and obese (3.9±1.89 vs. 1.8±1.15, P<0.01) subjects. Conclusions: CGES at a tachygastrial frequency enhances postprandial fullness and satiety, and delays gastric emptying. Its therapeutic potential for obesity needs to be studied.