Long-term Omeprazole Therapy in Peptic Ulcer Disease: Gastrin, Endocrine Cell Growth, and Gastritis

Background: The effects of chronic drug-induced hypergastrinemia on the exocrine and endocrine stomach are still incompletely understood. Chronic hypergastrinemia in rats and humans is associated with gastric argyrophil cell hyperplasia.

Methods: Seventy-four patients with chronic ranitidine-resistant ulcerations were treated chronically with omeprazole (median observation period 48 [6-84] months).

Results: Median fasting serum gastrin levels increased from a pretreatment value of 74-145 pg/mL after 3 months. No further increase was observed thereafter. The finding of atrophic gastritis increased from 1.8% to 20.8% after 5 years. A doubling of the mean argyrophil cell volume density (0.36% vs. 0.74% after 5 years; P < 0.01%) was paralleled by a decrease in the normal endocrine cell growth pattern from 64.3% to 33.3% and an increase in micronodular hyperplasia (8.9% vs. 16.7%). These changes correlated with the severity of corpus gastritis and seemed to be more disease- than drug-related. No statistically significant changes were observed in the antral G- and D-cell volume densities under therapy.

Conclusions: Long-term omeprazole therapy in humans results in moderate hypergastrinemia and a significant argyrophil cell hyperplasia, which are correlated to the grade of corpus gastritis. Because hypergastrinemia and gastritis are closely related, it is difficult to quantitatively assess their respective role in this process.