Changes in acid secretion over the years. A 30-year longitudinal study

We studied the effect of aging on gastric acid secretion in 11 physicians who had augmented histamine tests while at medical school in 1962. One of them had a duodenal ulcer at the time. The augmented histamine test was repeated in 1991 and, in addition, upper gastrointestinal endoscopy was done to exclude peptic ulcer and to obtain biopsies for histologic analysis and assessment of Helicobacter pylori status. The mean basal acid output decreased from 7.3 to 1.9 mEq/hr during the 30-year period of follow-up (p < 0.001), and the mean maximum acid output decreased from 29.9 to 20.3 mEq/hr (p < 0.01). The maximum acid output data showed a profound decrease in 4 of the 11 participants, a lesser decrease in 4, and a minimal increase in the remaining 3. Histologic analysis suggested a greater likelihood of atrophic gastritis, H. pylori infection, or both in participants showing a pronounced decrease in acid secretion with aging.