Damp housing is a risk factor for atopic asthma in a First Nations population of adults

Abstract

While damp housing is a recognized risk factor for asthma and atopy in children, its importance for adult health is inconclusive. We investigated the relationship between damp housing and adult atopic and non-atopic asthma in two Canadian First Nations communities. Methods: As part of the First Nations Longitudinal Respiratory Health Study, initiated in 2012, participating adults completed a health and environmental questionnaire followed by clinical assessment of atopy. Asthma was defined as any doctor diagnosed asthma. Atopic asthma included asthma and a positive skin prick test (SPT) ≥ 3mm to any of 6 allergens including house dust mite, three mold species, cat, and local grasses. Major household factors assessed included recent household damage caused by dampness; presence of mold and mildew; pets; and smoking. Multinomial logistic regression models with 3 outcomes [non-atopic asthma, atopic asthma and no asthma (referent)] were used to assess associations between asthma phenotypes and damp housing factors adjusting for covariates. Results: Of the 874 participants, 669 had allergy testing. The prevalence of asthma and atopy was 14.9 % and 21.1%, respectively. The most prevalent SPT responses were to cat (11.1%) and Cladosporium (7.9%). Of those with asthma, 28.0% were atopic. While mold or mildew in the home was not associated with asthma phenotypes, adults with atopic asthma were more likely to live in houses with home dampness (adjusted odds ratio: 3.4, 95% confidence interval: 1.41–8.17). No such associations were found for non-atopic asthma. Conclusion: This study supports the evidence that home dampness is an important domestic risk factor for adults with an atopic asthma history.