Effects of breastfeeding, reducing allergens and dietary interventions for primary prevention of eczema in predisposed infants: systematic review

Introduction: Eczema affects about 20% of children and is the most common chronic disease in childhood. There is substantial uncertainty regarding the effectiveness of specific preventive measures. Methods: We conducted a systematic review on the primary preventive effects of breastfeeding in predisposed infants, reducing allergens in predisposed infants and dietary interventions in infants. We searched Medline, Embase, and The Cochrane Library up to May 2009 with the help of BMJ Clinical Evidence. Results: We found no direct information from RCTs on the effects of breastfeeding straight after birth on the development of eczema in infants. One RCT looking at reducing allergens found no significant difference in the development of eczema between use of a mite impermeable mattress encasing for the child's bed versus a simple educational package on allergen avoidance versus basic information about allergies at 24 months. One systematic review found no significant difference between maternal antigen avoidance and no avoidance during pregnancy or during pregnancy and lactation in the incidence of eczema during the first 12 to 18 months of life. One RCT found that, compared with no avoidance, maternal antigen avoidance significantly decreased mean gestational weight gain. A systematic review found that probiotics significantly reduced the incidence of eczema, but not in the atopic eczema subgroup. One subsequent RCT found that Lactobacillus rhamnosus reduced the proportion of children with eczema at 2 years; however, it found no significant difference between Bifidobacterium animalis and placebo. A second subsequent RCT found no significant difference between Bifidobacterium longum and no probiotic in the proportion of infants with eczema at 1 year. Conclusion: While an early introduction of probiotics (in last trimester and/or shortly after birth) is likely to be beneficial in the prevention of infant eczema, the effects of breastfeeding after birth, reducing allergens and maternal antigen avoidance are unknown.