Abstract
The direct urease test was used in 462 patients with normal upper digestive tracts, 108 with duodenal ulcers and 43 with gastric ulcers who attended for upper digestive endoscopy in a prospective study. There was a strong association between Helicobacter pylori infection and current cigarette smoking in patients with normal endoscopy (49.6% vs 35.5%, P < 0.01). The associations of peptic ulcer both with H. pylori infection and cigarette smoking were also confirmed. The excess of peptic ulcer disease in cigarette smokers may be explained by their increased susceptibility to H. pylori infection.