Tuesday, July 31, 2012
Association between traditional farming and childhood wheeze from the GABRIEL Advanced Study Group
The European GABRIEL Advanced Studies project has provided a large body of data and samples for investigating effects of traditional farm environments on childhood asthma and atopy. Research on the GABRIELA cohort has demonstrated that traditional farming environments like those found in Europe have a protective effect on childhood atopy and, less consistently, childhood asthma. Yet, recent findings show that microbial diversity in farming environments appears to play a stronger role for asthma than for atopy. This month’s issue holds another important report on the impact of farm life on different childhood wheeze phenotypes by Fuchs et al. (J Allergy Clin Immunol 2012;130:382-388.e6).
Fuchs et al note that there are different wheeze phenotypes that correlate to different clinical outcomes, and that comorbid atopy complicates the search for wheeze-specific farm effects. To address this, the authors partition the study population into atopic and non-atopic children. In addition to analyzing the farm effect on atopy, they further investigate the effect on different wheeze phenotypes (transient, current, persistent, late-onset), airway inflammation and lung function for atopic and non-atopic children, separately.
They report that farm environment has a significant beneficial effect on all wheeze phenotypes. This protective effect was independent of atopic sensitization. This was different for lung mechanics as measured by lung function and on airway inflammation, on which farming had no appreciable overall effect. However, farm-exposed atopic children had less severe lung function impairment and lower exhaled nitric oxide (FeNO) than non-exposed atopic children.
Fuchs et al. speculate that farming’s protective effects are mediated through antiviral activities of the innate immune system that minimize respiratory infections. Future steps in their research to better elucidate underlying mechanisms will be analyses in prospective setups and studies further including the analysis of innate and adaptive immune mechanisms related to defense against viral infections and the role of the microbiome in upper and lower airways herein.