Elbejjani MA, et al. - In this retrospective cohort study, the correlations of H. pylori seropositivity with incident all-cause and Alzheimer's disease (AD) dementia and with AD-related mortality among US adults was examined. Researchers used data from the National Health and Nutrition Surveys III, phase 1 (1988–1991) and 1999–2000 linked with Medicare and National Death Index registries. The findings from the present study suggested that H. pylori seropositivity's was directly associated with AD mortality, all-cause dementia, and AD dementia, but only in men and higher socioeconomic status groups.