Over the years a number of studies in various countries have been considering the relationship between indoor dampness, mould and asthma. However, to date the results have been inconclusive. Now a recently published systematic review claims that dampness and mould poses a significant risk for developing asthma.
The systematic review, which was published in PlosOne, considered a total of 16 studies that had been published between 1990 and March 2012. Combining the studies allowed for a total of 35857 participants. In order for the studies to be included in the review, they needed to have been cohort or longitudinal studies or incident case-control studies. Moreover, a key requirement was that the studies did not report asthmatics at baseline as the purpose of the review was to establish the development of asthma. In addition to critically evaluating those studies, the authors also carried out separate meta-analyses to see whether the relationships investigated differed depending on the type of exposure. The types of exposure included; visible mould, mould odour, water damage and dampness. The key findings indicated that the presence of dampness and mould increased the risk for developing asthma by 31- 50%. However, the risk was not increased by the presence of water damage. Based on this, the authors concluded that their findings support the need for preventative and remediation actions against indoor dampness and mould.
Overall, this review benefitted from including only the most methodologically robust studies that assessed the risk prior to the onset of asthma. However, as with any secondary analysis, the findings can only be as strong as the initial studies considered. Therefore a limitation of the current review is that the emphasis on quantitative analysis does not permit room for discussion of limitations in the primary studies that may have affected their results. Still, this may not be necessary as the study complements a recent qualitative review which is comparable to these findings’.
Although, we are not surprised to hear that the associations between these factors are significant, we do believe that the findings are valuable and should not be disregarded in future studies.