Meta-analyses of the associations of respiratory health effects with dampness and mold in homes

The Institute of Medicine (TOM) of the National Academy of Sciences recently completed a critical review of the scientific literature pertaining to the association of indoor dampness and mold contamination with adverse health effects. In this paper, we report the results of quantitative meta-analyses of the studies reviewed in the TOM report plus other related studies. We developed point estimates and confidence intervals (CIs) of odds ratios (ORs) that summarize the association of several respiratory and asthma-related health outcomes with the presence of dampness and mold in homes. The ORs and CIs from the original studies were transformed to the log scale and random effect models were applied to the log ORs and their variance. Models accounted for the correlation between multiple results within the studies analyzed. Central estimates of ORs for the health outcomes ranged from 1.34 to 1.75. CIs (95%) excluded unity in nine of 10 instances, and in most cases the lower bound of the CI exceeded 1.2. Based on the results of the meta-analyses, building dampness and mold are associated with approximately 30-50% increases in a variety of respiratory and asthma-related health outcomes.