Article

Probiotic Administration in Early Life, Atopy, and Asthma: A Meta-analysis of Clinical Trials

Department of Pediatrics, University of Pittsburgh, Pittsburgh, Pennsylvania, United States
PEDIATRICS (Impact Factor: 5.47). 08/2013; 132(3). DOI: 10.1542/peds.2013-0246
Source: PubMed

ABSTRACT

Background and objective:
Probiotics may reduce the risk of atopy and asthma in children. However, results from clinical trials have been conflicting, and several of them may have been underpowered. We performed a meta-analysis of randomized, placebo-controlled trials to assess the effects of probiotic supplementation on atopic sensitization and asthma/wheeze prevention in children.

Methods:
Random-effects models were used to calculate pooled risk estimates. Meta-regression was conducted to examine the effect of potential factors on probiotics efficacy.

Results:
Probiotics were effective in reducing total immunoglobulin E (IgE) (mean reduction: -7.59 U/mL [95% confidence interval (CI): -14.96 to -0.22]; P = .044). Meta-regression showed that the reduction in IgE was more pronounced with longer follow-up. Probiotics significantly reduced the risk of atopic sensitization when administered prenatally (relative risk: 0.88 [95% CI: 0.78 to 0.99]; P = .035 for positive result on the skin prick test and/or elevated specific IgE to common allergens) and postnatally (relative risk: 0.86 [95% CI: 0.75 to 0.98]; P = .027 for positive result on skin prick test). Administration of Lactobacillus acidophilus, compared with other strains, was associated with an increased risk of atopic sensitization (P = .002). Probiotics did not significantly reduce asthma/wheeze (relative risk: 0.96 [95% CI: 0.85 to 1.07]).

Conclusions:
Prenatal and/or early-life probiotic administration reduces the risk of atopic sensitization and decreases the total IgE level in children but may not reduce the risk of asthma/wheeze. Follow-up duration and strain significantly modified these effects. Future trials for asthma prevention should carefully select probiotic strain and consider longer follow-up.

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    • "Various studies have investigated the potential of probiotics, both for primary prevention and for treatment of eczema and other atopic diseases. Results are inconsistent; while some studies have shown a preventive effect of probiotics on the development of eczema, others showed no effects (Elazab et al., 2013; Panduru et al., 2015). This inconsistency could be explained by differences in study design, amount and duration of probiotic supply, and the strain-specific effects of probiotic bacteria. "
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