Quantity and diversity of environmental microbial exposure and development of asthma: a birth cohort study

摘要: Background Early-life exposure to environmental microbial agents may be associated with the development of allergies. The aim study was identify better ways characterize as a predictor respiratory symptoms and allergies. Methods A birth cohort 410 children followed up until 6 years age. Bacterial endotoxin, 3-hydroxy fatty acids, N-acetyl-muramic acid, fungal extracellular polysaccharides (EPS) from Penicillium Aspergillus spp., β-D-glucan, ergosterol, bacterial or quantitative polymerase chain reactions (qPCRs) were analyzed dust samples collected at 2 months Asthma, wheezing, cough, atopic dermatitis assessed using repeated questionnaires. Specific IgEs determined age 1 6 years. Results Only few associations found between single markers studied outcomes. In contrast, score for total quantity exposure, that is, sum indicators fungi (ergosterol), Gram-positive (muramic acid) bacteria, Gram-negative (endotoxin) significantly (inverted-U shape) asthma incidence (P < 0.001): highest risk medium levels (adjusted odds ratio (aOR) 2.24, 95% confidence interval (95% CI) 0.87–5.75 3rd quintile) lowest level (aOR 0.34, CI 0.09–1.36 5th quintile). diversity score, detected qPCRs, inversely wheezing sensitization inhalant allergens. Conclusion Score predicted than independently amount dust. Better are needed in studies on asthma.