81.   Excess bicarbonate is excreted by the kidney, which means that a transient rise in urine bicarbonate excretion immediately follows maximal gastric acid secretion.

82.   We have shown that the fall in breakfast time UAO is a reliable predictor of gastric acid secretion in adult populations with a high prevalence of achlorhydric subjects.

83.   However, acid secretion in old subjects without atrophy was not different to that in young subjects, irrespective of H pylori status.

84.   Using multiple linear regression analysis, gastritis with atrophy was the only factor that had an independent negative effect on acid secretion.

85.   In healthy men without atrophy, gastric acid secretion is preserved with ageing and is independent of H pylori status.

86.   Atrophy, which is closely related to H pylori infection, is associated with a decline in acid secretion.

87.   The relationship between H pylori, age, and gastric acid secretion is important as H pylori infection causes active chronic gastritis which may progress to gastric atrophy.

88.   H pylori has variable effects on serum gastrin concentrations and gastric acid secretion.

89.   On a separate morning, within one week of the acid secretion studies, each subject underwent oesophagogastroduodenoscopy.

90.   For gastric acid secretion, basal serum gastrin was considered in addition to these three variables.