Probiotic administration in early life, atopy, and asthma: a meta-analysis of clinical trials

Pediatrics. 2013 Sep;132(3):e666-76. doi: 10.1542/peds.2013-0246. Epub 2013 Aug 19.

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.

Keywords: atopic sensitization; childhood asthma; childhood atopy; intestinal microbiome; meta-analysis; probiotics; total IgE.

Publication types

  • Meta-Analysis

MeSH terms

  • Adolescent
  • Asthma / immunology
  • Asthma / prevention & control*
  • Child
  • Child, Preschool
  • Dermatitis, Atopic / immunology
  • Dermatitis, Atopic / prevention & control*
  • Double-Blind Method
  • Female
  • Follow-Up Studies
  • Humans
  • Immunoglobulin E / blood
  • Infant
  • Infant, Newborn
  • Male
  • Pregnancy
  • Probiotics / administration & dosage*
  • Randomized Controlled Trials as Topic
  • Respiratory Hypersensitivity / immunology
  • Respiratory Hypersensitivity / prevention & control*
  • Risk
  • Treatment Outcome

Substances

  • Immunoglobulin E