Association Between House Dust Endotoxins and Increased All-Cause Mortality in Adults

Background: Exposure to house dust endotoxins is known to cause diseases across various organ systems; however, their effect on mortality remains unclear.Objective: This study is aimed at investigating the association between house dust endotoxins and mortality in US adults.Methods: National Health and Nutrition Examination Survey data from 2005 to 2006 were used in this study. Participants were linked to mortality data from the date of the survey through December 31, 2019. A multivariate Cox regression analysis was used to determine the association between house dust endotoxins and mortality. All analyses were performed in the overall population and across different sensitization statuses.Results: This cohort study included 3171 adults aged 20 years or older (weighted median age (P25-P75): 45 (32-58) years; 49.2% male). Among them, 1287 participants were sensitized to inhalant allergens. During a median follow-up of 13.8 years, 672 deaths occurred. In participants sensitized to inhalant allergens, house dust endotoxins were significantly associated with all-cause mortality. The hazard ratio (HR) comparing the highest and lowest tertiles of house dust endotoxin levels was 1.98 (95% confidence interval (CI): 1.32-2.97) for all-cause mortality. An association was observed between endotoxin concentration and cardiovascular disease mortality when analyzed as a continuous variable (HR: 1.29, 95% CI: 1.01-1.56). In nonsensitized participants, no significant association was found between house dust endotoxins and mortality.Conclusion: Exposure to house dust endotoxins was associated with all-cause mortality in adults sensitized to inhalant allergens.