Marching cohort of Helicobacter pylori infection over two decades (1988–2007): combined effects of secular trend and population migration

SUMMARY The prevalence of Helicobacter pylori infection is decreasing in developed countries. In this study we included 22 612 patients in whom a first culture of gastric biopsy (routinely performed in our medical centres) yielded an interpretable result over a 20-year period (1988–2007) in Brussels. The effects of patients’ age, gender and ethnic background were analysed. The overall proportion of H. pylori-infected patients was 37 . 7 %, with a progressive decline over time (P<10 x5 ). A gender effect was observed in adults. The lowest infection rate was observed in Western European patients (n=11 238) with respectively 36 . 2% and 15 . 2 % infected subjects in 1988 and 2007, compared to 71 . 7 % and 40 % in North African patients (n=3200) (P<10 x5 ). However, no trend of decline was observed over time in North African children aged f9 years. These data show the effects of time, age and ethnicity on the prevalence of H. pylori infection, and its complex heterogeneity in the same cosmopolitan urban area.