House dampness linked to pediatric wheeze worldwide
medwireNews: Results from an international study confirm that damp housing conditions are significantly associated with past and current wheeze in children.
Phase Two of the International Study of Asthma and Allergies in Childhood, which involved 46,051 children from 20 countries, also highlights the importance non-allergic causes of wheezing, particularly in less affluent countries, by showing that the association is true in both atopic and non-atopic children.
"Our results confirm that dampness is a potentially modifiable risk factor for wheeze world-wide," say authors Gudrun Weinmayr (Ulm University, Germany) and colleagues.
After adjusting for confounders, the odds for wheeze in the past year were 54% greater in children aged 9-11 years old currently exposed to dampness (damp spots and/or mould spots in the child's home) than in unexposed children. And this effect was significantly stronger in children living in non-affluent areas, who had an 80% increased odds for wheeze with current exposure. This compared with a lower but still significant 39% increased odds among exposed children in affluent areas.
And, among both children currently exposed and those only exposed in the first year of life, dampness was significantly associated with the odds for severe wheeze, having four or more wheezing attacks per week, having speech-limiting wheeze, and wheeze disturbing sleep, among those with wheeze.
Notably, there was no significant difference between the odds for wheeze on dampness exposure between atopic and non-atopic children.
And, while house dust mite concentrations and house dust mite sensitization were higher in damp houses, they were not associated with the likelihood for wheeze.
There was also a significant effect of dampness on rates of phlegm and rhinitis symptoms, particularly for exposed versus nonexposed children in non-affluent countries for whom the odds for rhinoconjunctivitis were increased 2.17-fold compared with 1.37-fold for those in affluent countries.
"Our results stress the importance of non-atopic processes, which is of considerable importance given that only relatively small fractions of asthma, rhinitis and eczema symptoms are attributable to atopy in non-affluent centres and even in affluent countries non-atopic symptoms are frequent," comment Weinmayr and team in Clinical and Experimental Allergy.
They add: "Further research is needed to investigate these non-allergic pathways, the lesser contributing role of house dust mite allergens, and the timing of the relevant environmental exposures."
medwireNews (www.medwirenews.com) is an independent clinical news service provided by Springer Healthcare Limited. © Springer Healthcare Ltd; 2013
By Kirsty Oswald, medwireNews Reporter