Relationship Between Low-Dose Aspirin-Induced Gastric Mucosal Injury and Intragastric pH in Healthy Volunteers

Background and Aims Gastric acid plays an important role in the pathogenesis of gastric mucosal lesions. We investigated whether aspirin-induced gastric mucosal injury might have any association with the intragastric pH. Materials and Methods Fifteen healthy, Helicobacter pylori -negative volunteers randomly underwent the four different 7-day regimens: (1) aspirin 100 mg, (2) rabeprazole 10 mg, (3) aspirin 100 mg + rabeprazole 10 mg, and (4) aspirin 100 mg + rabeprazole 40 mg. Gastric mucosal injury based on the modified Lanza score (MLS), 24-h intragastric pH, and histopathology of gastric mucosa were evaluated prior to the start and on day 7 of each regimen. Results The median MLSs were 0 in the baseline and the rabeprazole 10 mg regimen. The median MLS in the aspirin regimen was 3, while those in both aspirin + rabeprazole 10 mg and aspirin + rabeprazole 40 mg regimens were 0. Rabeprazole significantly prevented the gastric mucosal injury by aspirin ( P = 0.001 for rabeprazole 10 mg and P = 0.005 for rabeprazole 40 mg). The MLSs were negatively correlated with the 24-h intragastric pH ( P = −0.711,