Systematic review with meta-analysis: the worldwide prevalence of Helicobacter pylori infection

Background: The epidemiology of Helicobacter pylori infection is poorly understood. Aim: To establish the reported regional and national prevalence of H. pylori infection, stratified by age and gender. Methods: All relevant English publications from 2000 to 2017 cited by PubMed and Scopus were retrieved using comprehensive combinations of keywords. The overall prevalence of H. pylori was estimated using both random effect and fixed effect meta-analyses, and presented as prevalence rate (% and 95% CI). The analyses were extended by separation into gender and age groups. Results: A total of 14 056 records were obtained initially. After applying exclusion criteria in several steps, 183 studies were selected. Analysis of 410 879 participants from 73 countries in six continents revealed an overall prevalence of 44.3% (95% CI: 40.9-47.7) worldwide. This rate ranged from 50.8% (95% CI: 46.8-54.7) in developing countries compared with 34.7% (95% CI: 30.2-39.3) in developed countries. The global H. pylori infection rate was 42.7% (95% CI: 39-46.5) in females compared to 46.3% (95% CI: 42.1-50.5) in males. The prevalence in adults (≥18 years) was significantly higher than in children (48.6% [95% CI: 43.8-53.5] vs 32.6% [95% CI: 28.4-36.8], respectively). There was a statistically nonsignificant decrease in the prevalence in 2009-2016 compared with the 2000-2009 period. Conclusions: The observed differences between countries appear to be due to economic and social conditions. H. pylori infection can be a benchmark for the socioeconomic and health status of a country. Further studies are suggested to investigate the natural history of the acquisition of H. pylori infection from childhood into adult life.