Helicobacter pylori colonization and diarrhoeal illness: results of a population-based cross-sectional study in adults.

It has been suggested that Helicobacter pylori colonization may protect against diarrhoeagenic gastrointestinal infections. The aim of this analysis was to investigate the association between H. pylori infection and the frequency of diarrhoeal episodes among adults. Helicobacter pylori infection status was determined by 13C-urea breath test. Overall, 784 adults (mean age: 48.7 +/- 17.7; range 18-85 years) who participated in two epidemiological studies were included in the analysis. Overall H. pylori prevalence was 25.5%. Episodes of diarrhoea within prior 3 months were less often reported for H. pylori infected subjects compared with H. pylori negative subjects (40.2 vs. 51.6%, p = 0.016). Compared to H. pylori negative subjects the odds ratio (OR) for the occurrence of diarrhoea within the prior 3 months was 0.63 (95% CI: 0.45-0.87) for H. pylori infected subjects. After adjustment for covariates the OR was 0.67 (95% CI: 0.47-0.95). These results support the hypothesis that colonization with H. pylori may protect from gastrointestinal infections that cause diarrhoea.