Meta-Analysis of Risk Factors Associated with Gastric Cancer Development in Patients with Helicobacter pylori infection

Gastric cancer (GC) is one of the leading causes of cancer death around the world, with infection due to Helicobacter pylori (H. pylori) being the most important modifiable risk factor. There is a great deal of research done, yet there continues to be conflicting evidence concerning the intersection of H. pylori infection, genetics, and the environment with gastric cancer development. This meta-analysis seeks to estimate the odds of H. pylori-infected individuals developing GC and the relevance of bacterial virulence, genotype of the host, and lifestyle. A systematic search across Pubmed, Scopus, Web of Science, and the Cochrane Library was performed in order to find case-control, cohort, and randomized controlled studies on H. pylori infection and GC risk factors. Odds ratios (ORs) and relative risks (RRs) were calculated through statistical modelling of fixed- or random-effects pooled estimates meta-regression models after assessing heterogeneity. Evaluations of sensitivity analyses and publication bias were conducted through Egger's test and visualized through funnel plots. In the meta-analysis, 50 studies were analyzed, showing that H. pylori infection had a strong association with the development of gastric cancer (GC) 555555555(RR = 3.4, 95% CI: 2.8–4.1, p < 0.001). CagA+ H. pylori strain infections further resulted in an increased risk of GC (OR = 3.9, 95% CI: 3.0–5.0, p < 0.001). Other host factors, such as IL-1β and TNF-α polymorphisms, had higher odds of developing GC (OR = 2.9, p < 0.01). Moreover, other dietary and lifestyle choices, which included high salt consumption (OR = 2.5), processed meat (OR = 1.9), tobacco (OR = 2.7), and alcohol (OR = 2.2) use, were also risk factors. This meta-analysis adds evidence to the H. pylori theory of gastric cancer, claiming it is one of the leading causes of gastric cancer (GC) development, with bacterial virulence, genetics, and lifestyle serving as modifiers. Increased attention should be paid to routine screening and prophylactic treatment in these populations.