Abstract
One hundred and seventy healthy subjects and 1881 patients with gastrointestinal diseases were examined with the augmented histamine test. Achlorhydria and hypochlorhydria were defined by a pH in gastric juice higher than 3.3 after stimulation in combination with a pH fall less, or more, than one pH unit during the test. The incidence of achlorhydria was 4.7 per cent in healthy subjects and 6.4 per cent in patients, and the incidence of hypochlorhydria was 4.1 per cent in healthy subjects and 3.8 per cent in patients. Both secretory defects were uncommon in subjects younger than 50 years of age. The incidence of achlorhydria in patients increased rapidly from 1.8 per cent in the fifth decade to 18.5 per cent in the eighth decade, and a similar increase was observed in healthy subjects. No sex differences were found. Seventy five per cent of achlorhydric and 68 per cent of hypochlorhydric subjects were observed in patients with pernicious anemia, gastric cancer, postoperative stomach or gastritis. The incidences of achlorhydria and hypochlorhydria in patients with gastrointestinal diseases did not differ significantly from those in healthy subjects, and the secretory defects appeared to be primarily related to advanced age. Control studies, using a dialysis bag method, revealed that 42 ± 11.3 per cent of cases of achlorhydria should be more correctly regarded as hypochlorhydric.