Higher levels of the archaea Methanosphaera stadtmanae DNA in feces were significantly associated with a lower risk for asthma in children, according to the results of a recent study published in the Journal of Allergy and Clinical Immunology.
Fecal samples from school-aged children within the Dutch KOALA Birth Cohort Study were analyzed using quantitative polymerase chain reaction to quantify the levels of DNA from M stadtmanae and Methanobrevibacter smithii. Associations between the presence or absence of each archaeal species and parent-reported asthma at 6 to 10 years of age were examined. Secondary outcomes were questionnaire-reported eczema, total serum immunoglobulin E levels, sensitization to aeroallergens and food allergens, and lung function.
Among the 1432 requests for fecal samples, 672 samples were received. Of the samples received, those with transport times >4 days were excluded. Ultimately, 472 samples were analyzed by quantitative polymerase chain reaction.
M stadtmanae and M smithii were detectable in 8.3% and 78.2% of samples, respectively. Overall, the presence of M stadtmanae was associated with a lower risk for asthma at 6 to 10 years of age. However, no significant interaction was found between M stadtmanae exposure and parental asthma history.
M stadtmanae appeared to be associated with a slightly lower likelihood of eczema and aeroallergen and food allergen sensitization, but these associations did not reach statistical significance. There were no significant associations between M smithii and any outcome.
The study authors wrote, “Due to the low prevalence of M stadtmanae and cross-sectional study design, our results should be interpreted with caution.” They added, “Although bacterial species not examined in our analysis might confound this association, we speculate that a mechanistic link between M stadtmanae and allergic disease appears plausible.”
Barnett D, Mommers M, Penders J, Arts ICW, Thijs C. Intestinal archaea inversely associated with childhood asthma [published online February 20, 2019]. J Allergy Clin Immunol. doi:10.1016/j.jaci.2019.02.009