Helicobacter pylori infection in the Australian community: current prevalence and lack of association with ABO blood groups

Aims: To assess the current prevalence of Helicobacter pylori infection in an Australian urban population sample and to relate this to age, gender and ABO and Rhesus blood groups. Methods: We performed a prospective epidemio­logical survey of H. pylori serological status in 500 consecutive voluntary blood donors who presented for the purpose of blood donation at the central ­Melbourne branch of the Australian Red Cross Blood Service, Victoria, Australia, and gave a Melbourne suburban home address. Results: The overall prevalence of specific anti‐H. pylori IgG antibodies in this cohort was 32% (95% confidence interval = 28?36%) and H. pylori sero­positivity increased with age. The rate of H. pylori infection was not significantly different in men and women, with anti‐H. pylori IgG anti­bodies detected in 35% (97/277) of men compared with 28% (63/233) of women (P = 0.12). Similarly, H. pylori serological status was not significantly different between subjects of different ABO (P = 0.18) or Rhesus blood groups (P = 0.55). Conclusion: This study showed that, contrary to expectation, the updated prevalence of H. pylori seropositivity (32%) in this Melbourne sample is at least as high as that found in previous Australian studies over the past 19 years. Seropositivity increased with age, and was not related to gender, confirming the infection pattern seen in other developed nations. Despite epidemiological evidence of increased peptic ulcer disease in ABO blood group O subjects, and recent evidence that H. pylori adhesion to gastric epithelial cells is mediated by blood group epitopes, no significant association between blood groups and H. pylori serological status was detected. (Intern Med J 2003; 33: 163?167)