Prevalence of Helicobacter pylori in patients with gastro-oesophageal reflux disease: systematic review
Anan Raghunath, A Pali S Hungin, David Wooff, and Susan Childs
BMJ 2003; 326: 737.

Objectives: To ascertain the prevalence of Helicobacter pylori in patients with gastro-oesophageal reflux disease and its association with the disease.
Design: Systematic review of studies reporting the prevalence of H pylori in patients with and without gastro-oesophageal reflux disease.
Data sources: Four electronic databases, searched to November 2001, experts, pharmaceutical companies, and journals.
Main outcome measure: Odds ratio for prevalence of H pylori in patients with gastro-oesophageal reflux disease.
Results: 20 studies were included. The pooled estimate of the odds ratio for prevalence of H pylori was 0.60 (95% confidence interval 0.47 to 0.78), indicating a lower prevalence in patients with gastro-oesophageal reflux disease. Substantial heterogeneity was observed between studies. Location seemed to be an important factor, with a much lower prevalence of H pylori in patients with gastro-oesophageal reflux disease in studies from the Far East, despite a higher overall prevalence of infection than western Europe and North America. Year of study was not a source of heterogeneity.
Conclusion: The prevalence of H pylori infection was significantly lower in patients with than without gastro-oesophageal reflux, with geographical location being a strong contributor to the heterogeneity between studies. Patients from the Far East with reflux disease had a lower prevalence of H pylori infection than patients from western Europe and North America, despite a higher prevalence in the general population.