Association between Helicobacter pylori infection and Parkinson's disease: A systematic review and meta‐analysis

BACKGROUND: Helicobacter pylori infection is epidemiologically linked to Parkinson's disease (PD), though findings remain inconsistent. This study aimed to determine whether patients with PD have a higher prevalence of H. pylori infection than controls through an updated systematic review and meta-analysis and to explore heterogeneity through subgroup analyses. METHODS: A comprehensive literature search of relevant studies published till October 2024 was performed using PubMed, EMBASE and Cochrane Library databases. Studies examining the prevalence of H. pylori infection in patients with PD were included. Pooled odds ratios (OR) with 95% confidence intervals (CI) and pooled prevalence rates were calculated. Subgroup analyses were conducted based on geographical region, H. pylori detection methods and exclusion of individuals with prior eradication therapy. Sensitivity analyses and publication bias assessments were also performed. RESULTS: Twenty-three studies involving 7205 patients with PD and 41,937 controls were included in meta-analysis. Among studies reporting prevalence, the pooled prevalence of H. pylori infection in patients with PD was 39.0% (95% CI 26.5%-53.1%). In 13 studies comparing the prevalence of H. pylori infection between patients with PD and controls, H. pylori infection was found to be associated with PD (OR 1.328, 95% CI 1.165-1.514). Subgroup analyses showed consistent results and sensitivity analyses confirmed the robustness of the findings. Furthermore, no publication bias was observed. CONCLUSIONS: Patients with PD exhibit a higher prevalence of H. pylori infection than controls. These findings support a potential role of H. pylori infection in PD pathogenesis, although causality cannot be established.