Helicobacter pylori seropositivity and its association with incident all-cause and Alzheimer's disease dementia in large national surveys

Abstract

IntroductionInfectious agents were recently implicated in Alzheimer's disease (AD) and etiology of other dementias, notably Helicobacter pylori. MethodsWe tested associations of H. pylori seropositivity with incident all-cause and AD dementia and with AD-related mortality among US adults in a retrospective cohort study. Data from the National Health and Nutrition Surveys III, phase 1 (1988–1991) and 1999–2000 linked with Medicare and National Death Index registries, were used (baseline age ≥45 y, follow-up to 2013, Npooled = 5927). ResultsA positive association between H. pylori seropositivity and AD mortality was found in men (hazard ratioadj, pooled = 4.33, 95% confidence interval: 1.51–12.41, P = .006), which was replicated for incident AD and all-cause dementia, with hazard ratioadj, pooled = 1.45 (95% confidence interval: 1.03–2.04, P = .035) and hazard ratioadj, III = 1.44 (95% confidence interval: 1.05–1.98, P = .022), respectively. These associations were also positive among higher socioeconomic status groups. DiscussionIn sum, H. pylori seropositivity's direct association with AD mortality, all-cause dementia, and AD dementia was restricted to men and to higher socioeconomic status groups.