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

Abstract

Introduction: Infectious agents were recently implicated in Alzheimer's disease (AD) and etiology of other dementias, notably Helicobacter pylori.

Methods: We 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, N_pooled = 5927).

Results: A positive association between H. pylori seropositivity and AD mortality was found in men (hazard ratio_{adj, pooled} = 4.33, 95% confidence interval: 1.51-12.41, P = .006), which was replicated for incident AD and all-cause dementia, with hazard ratio_{adj, pooled} = 1.45 (95% confidence interval: 1.03-2.04, P = .035) and hazard ratio_{adj, III} = 1.44 (95% confidence interval: 1.05-1.98, P = .022), respectively. These associations were also positive among higher socioeconomic status groups.

Discussion: In 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.

Keywords: Aging; Alzheimer's disease; Dementia; Helicobacter pylori; Mortality.