Helicobacter pylori infection and gender: a meta-analysis of population-based prevalence surveys.

Although most of Helicobacter pylori-related diseases are associated with male gender, the role of gender as a risk factor for H. pylori infection is still debated. To assess the true association between H. pylori and gender, we conducted a meta-analysis of large, population-based studies where the measure of association had been adjusted at least for age and socioeconomic status, and obtained primary data from authors when information on gender associations were not presented. In 18 adult populations, the test of heterogeneity was not significant and male gender was significantly associated with H. pylori infection (summary odds ratio [OR] 1.16 [95% confidence interval (CI) 1.11, 1.22]). In 10 pediatric populations, the test of heterogeneity was of borderline significance, and the summary OR computed using a random effect model was close to 1 (summary OR 1.03 [95% CI 0.91, 1.17]). This study confirms the male predominance of H. pylori infection in adults as a global and homogeneous phenomenon; such predominance is not apparent in children. Differential antibiotic exposure or differential protective immunity between genders may explain the different results observed between children and adult studies.