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


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.

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

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]).

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.

Download full-text


Available from: Angelico Mendy,
  • Source
    • "However, if the new environment induces epigenetic changes, a transgenerational amplification of the atopic phenotype would be expected even with stable exposure (Figure 5). Furthermore, according to this hypothesis, it would be expected that the benefit of some interventions to prevent allergies (such as pro- and prebiotics) could take a full generation before reaching their full effect, hence possibly the somewhat disappointing results so far [66]. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Epigenetics of asthma and allergic disease is a field that has expanded greatly in the last decade. Previously thought only in terms of cell differentiation, it is now evident the epigenetics regulate many processes. With T cell activation, commitment toward an allergic phenotype is tightly regulated by DNA methylation and histone modifications at the Th2 locus control region. When normal epigenetic control is disturbed, either experimentally or by environmental exposures, Th1/Th2 balance can be affected. Epigenetic marks are not only transferred to daughter cells with cell replication but they can also be inherited through generations. In animal models, with constant environmental pressure, epigenetically determined phenotypes are amplified through generations and can last up to 2 generations after the environment is back to normal. In this review on the epigenetic regulation of asthma and allergic diseases we review basic epigenetic mechanisms and discuss the epigenetic control of Th2 cells. We then cover the transgenerational inheritance model of epigenetic traits and discuss how this could relate the amplification of asthma and allergic disease prevalence and severity through the last decades. Finally, we discuss recent epigenetic association studies for allergic phenotypes and related environmental risk factors as well as potential underlying mechanisms for these associations.
    Allergy Asthma and Clinical Immunology 05/2014; 10(1):27. DOI:10.1186/1710-1492-10-27 · 2.03 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background Low birth weight is strongly correlated with an increased risk of adult diseases. Additionally, low birth weight might be a risk factor for asthma later in life. Methods A systematic literature search of the PubMed database from 1966 to November 2013 was conducted. The criteria for inclusion of papers were as follows: case–control or cohort studies; the odds ratio (OR) or risk ratio (RR) estimates with the corresponding 95% confidence intervals (CIs) were presented, or there were sufficient data for calculation; and studies were published in English up to October 2013. Random-effect and fixed-effect meta-analyses, meta-regression, and cumulative meta-analysis were conducted. Results Thirteen cohort studies and 1,105,703 subjects were included. The overall pooled RRs (95% CIs) of asthma risk for low birth weight were 1.162 (fixed-effects model, 95% CI, 1.128–1.197) and 1.152 (random-effects model, 95% CI, 1.082–1.222). In stratified analyses, the effect of low birth weight on childhood asthma was strong, particularly in studies conducted in Europe, those with a small sample size, and those published recently. A meta-regression analysis did not find significant determinants. Conclusions This meta-analysis shows that low birth weight significantly increases the risk of childhood asthma.
    BMC Pediatrics 10/2014; 14(1):275. DOI:10.1186/1471-2431-14-275 · 1.93 Impact Factor

  • Clinical Pediatrics 01/2014; 53(13). DOI:10.1177/0009922813518427 · 1.15 Impact Factor
Show more

Similar Publications