Helicobacter pylori infection is on the decline in the Western world.1 This is most likely related to improvements in sanitary conditions and socioeconomic status along with the widespread use of antibiotics. Hospitalisation and mortality rates for duodenal ulcer disease, gastric ulcer disease, and cancer of the gastric antrum and corpus, all clearlyH pylori related diseases, also have declined markedly between 1970 and 1995.2 In sharp contrast, hospitalisation and mortality rates for both gastro-oesophageal reflux disease (GORD) and oesophageal adenocarcinoma have increased during the same time interval. Although the hypothesis seemed quite radical in 1997,3 it appears that the decline in H pylori infection may explain these two opposing time trends.

Although initial studies were inconsistent,4 the majority of recent evidence from the USA,5 ,6 Europe,7and the Far East8 find that H pylori infection alone, regardless of virulence factors, protects from the development of severe reflux oesophagitis and its complications, such as Barrett's oesophagus and adenocarcinoma. Even more striking and consistent has been the protection reported from GORD related complications in patients with H pylori infection and the cagA⁺ virulent factor. Vicari and colleagues9 from the Cleveland Clinic were the first to report …