24-HOUR STUDY OF INTRAGASTRIC ACIDITY IN DUODENAL-ULCER PATIENTS AND NORMAL SUBJECTS USING CONTINUOUS INTRALUMINAL PH-METRY

The circadian pattern of intragastric acidity was assessed in 19 healthy subjects and 37 patients with active, endoscopically proven duodenal ulcer using 24-hr continuous intraluminal pH-metry. The median pH 24-hr profiles showed that ulcer patients had lower postprandial pH elevations and a smaller decline in acidity during the early morning hours when compared with controls. The after-lunch and -dinner the curve and maximum pH values were significantly higher in controls compared to ulcer patients. In the nighttime, the median pH values in controls were significantly higher during 9 PM to 12 PM (P = 0.02), 12 PM to 4 AM (P = 0.01), and 4 AM to 8 AM (P = 0.0008) compared to the ulcer patients. We conclude that the 24-hr acidity is higher in ulcer patients compared to healthy subjects and that the differences are particularly evident in the postprandial and nocturnal periods.