Burden of gastric cancer attributable to Helicobacter pylori in 27 countries from seven geographic regions in 2022

Background: Helicobacter (H.) pylori is the major risk factor of gastric cancer (GC). We aimed to estimate the population attributable fraction (PAF) of GC and the number of new GC cases and deaths for GC attributable to H. pylori in different countries worldwide in 2022. Methods: The PAF was estimated using country-specific pooled prevalence of H. pylori in the period 2000–2010 obtained through a systematic review and meta-analysis and a risk ratio of 5.9 for the association between H. pylori and GC. The absolute number of new GC cases and deaths for GC attributable to H. pylori was calculated using PAF and GC incidence and mortality reported by GLOBOCAN 2022. Results: The PAF of GC due to H. pylori was calculated for 27 countries. The average PAF was 69.7% ranging from 40.7% in Malaysia to 82.3% in South Africa. The PAF was > 70% in all countries in the analysis in Africa, East Mediterranean region and Latin America, apart from Mexico, and in some countries in Western Pacific region (China, Japan and Korea) and Europe (Poland, Spain and Albania). The largest number of GC cases and deaths for GC attributable to H. pylori was estimated in China (GC: 252,850, deaths:184,666) and Japan (GC: 92,166, deaths: 31,809). Conclusions: More than two-thirds of new GC cases in the countries in the analysis were attributable to H. pylori in 2022. Our estimates may contribute to better investigate cost-effectiveness of H. pylori screening strategies for GC prevention in different countries worldwide.