PURPOSE OF THE STUDY.
The purpose of this study was to determine if probiotic supplementation could modify the genetic predisposition to eczema based on toll-like receptor (TLR) gene variants in an at-risk infant population.
The study was a double-blind, randomized, placebo-controlled trial of 331 term infants with a paternal history of treated asthma, eczema, or hay fever.
Pregnant women were given daily supplementation with Lactobacillus rhamnosusstrain HN001, Bifidobacterium animalis subsp. lactis strain HN019, or placebo from 35 weeks’ gestation until birth. Breastfeeding mothers continued supplementation until 6 months of age, and all infants received daily supplementation until 2 years of age. Outcomes included development of eczema at multiple time points during the first 6 years of life, eczema severity (using SCORing Atopic Dermatitis; SCORAD), and identification of single nucleotide polymorphisms (SNPs) in TLR genes that were associated with increased risk of atopy, eczema, and SCORAD ≥10. Response to supplementation with HN001 and HN019 was also assessed.
Of the 311 subjects, 114 received HN019, 108 HN001, and 106 placebo. At the end of the study, 44% of HN019, 38% of HN001, and 48% of placebo subjects developed eczema (SCORAD ≥10). Fifty-four SNPs were selected for genotyping with identification of 10 variants that were significantly associated with atopy, 9 with eczema, and 8 with SCORAD ≥10. In subjects who received HN001, 20 SNPs were significantly associated with decreased risk of atopy, 26 with reduction of eczema development, and 18 with decreased risk of SCORAD ≥10. Three of these variants were associated with a significant risk reduction in all 3 variables. Only 2 variants provided similar risk reductions in those who received HN019.
This study found that supplementation with Lactobacillus rhamnosusstrain HN001 could reduce the risk of atopy and eczema development in subjects with TLR genetic variants typically associated with a higher risk of these diseases.
This study highlights the growing interest in the use of probiotics for the prevention and treatment of atopic disorders. Several studies have shown reduction in eczema risk, but the mechanism in which probiotics accomplish this has been unknown. The authors demonstrate the role of probiotic interaction with TLR SNP variants, identifying a novel mechanism through which risk reduction occurs. The study also suggests that this intervention should begin early, during pregnancy, to have significant benefit.
- Copyright © 2015 by the American Academy of Pediatrics