Efficacy of acotiamide on postprandial distress syndrome and epigastric pain syndrome depending on the estimated gastric acid secretion level.

BACKGROUND/AIMS: Gastric acid secretion is suspected to be a pivotal contributor to the pathogenesis of functional dyspepsia. The present study investigates the potential association of the gastric acid secretion estimated by measuring serum pepsinogen with therapeutic responsiveness to the prokinetic drug acotiamide. METHODS: Dyspeptic patients consulting participating clinics from October 2017 to March 2019 were prospectively enrolled in the study. The dyspeptic symptoms were classified into postprandial distress syndrome (PDS) and epigastric pain syndrome (EPS). Gastric acid secretion levels were estimated by the Helicobacter pylori infection status and serum pepsinogen using established criteria and classified into hypo-, normo-, and hyper-secretion. Each patient was then administered 100 mg acotiamide thrice daily for 4 weeks, and the response rate to the treatment was evaluated using the overall treatment efficacy scale. RESULTS: Of the 86 enrolled patients, 56 (65.1%) and 26 (30.2%) were classified into PDS and EPS, respectively. The estimated gastric acid secretion was not significantly different between PDS and EPS. The response rates were 66.0% for PDS and 73.1% for EPS, showing no significant difference. While the response rates were stable, ranging from 61.0% to 75.0% regardless of the estimated gastric acid secretion level among subjects with PDF, the rates were significantly lower in hyper-secretors than in non-hyper-secretors among subjects with EPS (42.0% vs 83.0%, P = 0.046). CONCLUSION: Although acotiamide is effective for treating EPS as well as PDS overall, the efficacy is somewhat limited in EPS with gastric acid hypersecretion, with gastric acid suppressants, such as proton pump inhibitors, being more suitable.