Is Helicobacter pylori associated with non-ulcer dyspepsia and will eradication improve symptoms? A meta-analysis

OBJECTIVES: To examine the association between Helicobacter pylori infection and non-ulcer dyspepsia, and to assess the effect of eradicating H pylori on dyspeptic symptoms in patients with non-ulcer dyspepsia. DESIGN: Systematic review and meta-analysis of (a) observational studies examining the association between Helicobacter pylori infection and non-ulcer dyspepsia (association studies), and (b) therapeutic trials examining the association between eradication of H pylori and dyspeptic symptoms in patients with non-ulcer dyspepsia (eradication trials). DATA SOURCES: Randomised controlled trials and observational studies conducted worldwide and published between January 1983 and March 1999. MAIN OUTCOME MEASURES: Summary odds ratios and summary symptom scores. RESULTS: 23 association studies and 5 eradication trials met the inclusion criteria. In the association studies the summary odds ratio for H pylori infection in patients with non-ulcer dyspepsia was 1.6 (95% confidence interval 1.4 to 1.8). In the eradication trials the summary odds ratio for improvement in dyspeptic symptoms in patients with non-ulcer dyspepsia in whom H pylori was eradicated was 1.9 (1.3 to 2.6). CONCLUSIONS: Some evidence shows an association between H pylori infection and dyspeptic symptoms in patients referred to gastroenterologists. An improvement in dyspeptic symptoms occurred among patients with non-ulcer dyspepsia in whom H pylori was eradicated.