INFLUENCE OF HELICOBACTER-PYLORI ON GASTRIC-MUCOSAL ADAPTATION TO NAPROXEN IN MAN

Our objective was to determine whether H. pylori influences gastric mu cosal injury and adaptation caused by naproxen. Twenty-four healthy vo lunteers, 12 H. pylori-positive and 12 H. pylori-negative, were given a 28-day course of naproxen 500 mg twice a day. They were each gastros coped to assess gastric mucosal damage and mucosal blood flow before a nd at 1, 7, and 28 days during treatment. Maximal gastric mucosal dama ge (median grade + IQR) occurred during the first 24 hr in both groups and was of similar magnitude (H. pylori-positive: 2.5, 2.0-3.0 P <0.0 1; H. pylori-negative: 2.0, 1.0-3.0 P <0.01). This damage was associat ed with a fall in antral but not corpus mucosal blood flow. With conti nued NSAID administration, gastric damage resolved confirming adaptati on (H. pylori-positive 1.0, 0-2.0, H. pylori-negative: 1.0, 0-1.0) and antral mucosal blood flow returned to baseline in both groups by day 28. These observations suggest that initial gastric mucosal injury is not influenced by H. pylori colonization and adaptation occurs regardl ess of its presence.