GASTRIC-ACIDITY IN OLDER ADULTS

Context.-Early studies suggested that gastric acidity declines as peop le age. However, sequelae of achlorhydria are uncommon in older people , making this conventional wisdom unlikely. Objective.-To ascertain th e prevalence of basal gastric acidity and atrophic gastritis (indicate d by serum pepsinogen ratio) in older adults. Design.-Cross-sectional study in a volunteer sample. Setting.-Retirement communities in suburb s of Kansas City, Mo. Subjects.-A total of 248 white male and female v olunteers aged 65 years or older living independently. Main Outcome Me asures.-Presence of basal unstimulated gastric acid was evaluated noni nvasively by having subjects swallow quininium resin. Gastric acid wit h a pH lower than 3.5 releases quinine, which is then absorbed and exc reted into urine, Atrophic gastritis was defined as a ratio of serum p epsinogen I/pepsinogen II of less than 2.9. Results.-Basal unstimulate d gastric content was acidic (pH <3.5) in 208 (84%) of 248 elderly sub jects. On retesting 66 subjects (35 normals and 31 hyposecretors), 28 (80%) of 35 had pH less than 3.5 both times, and 22 (71%) of 31 had pH of 3.5 or higher twice; in the remaining 16 subjects, low vs high gas tric pH changed between tests, Weighted population prevalence estimate s in this sample were 67% for consistent acid secretion, 22% for inter mittent secretion, and 11% for consistent gastric pH higher than 3.5. Whereas 14 (67%) of 21 consistent hyposecretors had serum pepsinogen r atios of less than 2.9, indicating atrophic gastritis, only 2 (5%) of 44 consistent or intermittent secretors of acid had ratios in this ran ge (P<.001). Conclusions.-In contrast to what is commonly stated, near ly 90% of elderly people in this study were able to acidity gastric co ntents, even in the basal, unstimulated state. Of those who were consi stent hyposecretors of acid, most had serum markers of atrophic gastri tis.