Helicobacter pylori infection, peptic ulcer, gastritis and risk of Parkinson's disease: A nationwide matched cohort study.

BackgroundGastrointestinal symptoms are frequent in Parkinson's disease (PD) and may precede diagnosis by decades, suggesting a possible role in its pathogenesis. Patients with PD have higher rates of Helicobacter pylori (H. pylori) infection than the general population, although its potential contribution to PD development remains unclear. Similarly, evidence linking gastritis and peptic ulcer to PD risk is limited.MethodsUsing the nationwide ESPRESSO cohort, we investigated associations between H. pylori infection, peptic ulcer, gastritis, and future risk of PD. Individuals diagnosed with these conditions between 1987 or 1990 and 2017 were matched to ≤5 referents from the general population by age, sex, calendar year, and county of residence. Stratified Cox models estimated hazard ratios (HRs), adjusting for country of birth, education, chronic obstructive pulmonary disease, and number of healthcare visits. Incident PD was identified from the National Patient Register.ResultsThe H. pylori cohort included 48,258 exposed individuals and 231,805 referents; the peptic ulcer cohort included 52,761 exposed individuals and 274,313 referents, while the gastritis cohort included 242,325 exposed individuals and 1,053,688 referents. H. pylori infection (HR: 1.14, 95% CI: 1.02-1.28) and gastritis (HR: 1.14, 95% CI: 1.09-1.19) were associated with a marginally increased PD risk, but we found no significant association in peptic ulcer (HR: 1.08, 95% CI: 0.98-1.19). We observed increased PD risk up to ten years after gastritis diagnosis and no time-varying association for H. pylori and peptic ulcer.ConclusionsH. pylori and gastritis may have some relevance for PD development but are unlikely to be major contributors to its pathogenesis.Plain language summary titleUsing gastrointestinal biopsies to explore the link between Helicobacter pylori infection, peptic ulcer, gastritis and Parkinson's disease: findings from a nationwide Swedish cohort study.