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World Allergy Organization-McMaster University Guidelines for Allergic Disease Prevention (GLAD-P): Probiotics
Alessandro Fiocchi1, Ruby Pawankar2, Carlos Cuello-Garcia3,4
1Pediatric Hospital Bambino Gesù, Vatican City, Italy.
Insights
Probiotic supplementation may not prevent allergies in children, but may offer benefits for eczema prevention. The World Allergy Organization (WAO) suggests conditional use in high-risk pregnancies, breastfeeding mothers, and infants, based on low-quality evidence.
Area of Science:
- Immunology
- Microbiology
- Pediatrics
Background:
- Allergic diseases affect 10-30% of infants, influenced by genetics and potentially modulated by intestinal microbiota.
- Probiotics, known to influence immune responses, have been investigated for allergy prevention.
- The World Allergy Organization (WAO) established a guideline panel to assess probiotic use for allergy prevention.
Purpose of the Study:
- To develop evidence-based recommendations on using probiotics for allergy prevention.
- To systematically review randomized controlled trials (RCTs) on probiotics and allergy prevention.
Main Methods:
- Systematic review of RCTs up to November 2014.
- Utilized the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.
- Considered health effects, patient values, preferences, and resource use.
Main Results:
- Current evidence does not support probiotic supplementation for reducing allergy risk in children.
- A likely net benefit was identified, primarily due to eczema prevention.
- Conditional recommendations suggest probiotic use in high-risk pregnant women, breastfeeding mothers, and infants, though evidence quality is very low.
Conclusions:
- WAO recommendations aim to guide decisions on probiotic use during pregnancy, breastfeeding, and infancy.
- The recommendations support parents, clinicians, and healthcare professionals.
- Evidence quality necessitates cautious interpretation of these conditional recommendations.
Background:
Prevalence of allergic diseases in infants, whose parents and siblings do not have allergy, is approximately 10% and reaches 20-30% in those with an allergic first-degree relative. Intestinal microbiota may modulate immunologic and inflammatory systemic responses and, thus, influence development of sensitization and allergy. Probiotics have been reported to modulate immune responses and their supplementation has been proposed as a preventive intervention.
Objective:
The World Allergy Organization (WAO) convened a guideline panel to develop evidence-based recommendations about the use of probiotics in the prevention of allergy.
Methods:
We identified the most relevant clinical questions and performed a systematic review of randomized controlled trials of probiotics for the prevention of allergy. We followed the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to develop recommendations. We searched for and reviewed the evidence about health effects, patient values and preferences, and resource use (up to November 2014). We followed the GRADE evidence-to-decision framework to develop recommendations.
Results:
Currently available evidence does not indicate that probiotic supplementation reduces the risk of developing allergy in children. However, considering all critical outcomes in this context, the WAO guideline panel determined that there is a likely net benefit from using probiotics resulting primarily from prevention of eczema. The WAO guideline panel suggests: a) using probiotics in pregnant women at high risk for having an allergic child; b) using probiotics in women who breastfeed infants at high risk of developing allergy; and c) using probiotics in infants at high risk of developing allergy. All recommendations are conditional and supported by very low quality evidence.
Conclusions:
WAO recommendations about probiotic supplementation for prevention of allergy are intended to support parents, clinicians and other health care professionals in their decisions whether to use probiotics in pregnancy and during breastfeeding, and whether to give them to infants.
