Probiotics may reduce risk of eczema among at-risk infants, preliminary study suggests

Treatment with certain probiotics prenatally and in the first years of life may offer infants at risk for allergies protection from eczema, a new study suggests. Scientists do not yet have a clear understanding of the role probiotics may play in the prevention of allergic disease. To gain insights, researchers in New Zealand set out to determine whether probiotic supplementation early in life could prevent development of eczema and atopy at 2 years. In their double-blind, randomized,...

Treatment with certain probiotics prenatally and in the first years of life may offer infants at risk for allergies protection from eczema, a new study suggests.

Scientists do not yet have a clear understanding of the role probiotics may play in the prevention of allergic disease. To gain insights, researchers in New Zealand set out to determine whether probiotic supplementation early in life could prevent development of eczema and atopy at 2 years. In their double-blind, randomized, placebo-controlled trial, pregnant women were randomized to take Lactobacillus rhamnosus HN001 (L. rhamnosus), Bifidobacterium animalis subsp lactis strain HN019, or placebo daily from 35 weeks gestation until 6 months if breastfeeding. In addition, the women's infants received the same treatment as their mothers from birth to 2 years (n=474). The primary endpoint was the infant's cumulative presence of eczema and point prevalence of atopy, using skin prick tests to common allergens, as assessed at 2 years.

Eczema was defined using the U.K. Working Party's Diagnostic Criteria for atopic dermatitis, modified for use in infants. Severity of eczema was measured using the Scoring Atopic Dermatitis (SCORAD) tool, with a score of at least 10 indicating eczema.

While infants receiving L. rhamnosus had a significantly (P=.01) reduced risk of developing eczema by 2 years (HR, 0.51; 95% CI, 0.30-0.85) compared with placebo, there was no risk reduction for eczema among infants who received B. animalis subsp lactis (HR, 0.90; 95% CI, 0.58-1.41). Neither of the probiotics significantly reduced the risk for atopy at 2 years (HR for L. rhamnosus, 0.74; 95% CI, 0.46-1.18, and HR for B. animalis subsp lactis, 0.82; 95% CI, 0.52-1.28).

The risk of developing SCORAD >=10 was significantly reduced by 2 years in the L. rhamnosus group.

L. rhamnosus was more likely than B. animalis subsp lactis to be present in the child's feces at 3 months (71.5% vs 22.6%). By 24 months, however, detection rates were similar.

The researchers noted there was no statistically significant effect of either probiotic on the likelihood of having a positive skin test result for any allergen, or for food allergens, at 2 years.

"In this study, treatment with L. rhamnosus for the first 2 years of life was associated with a reduction in the prevalence of any eczema by about half," the researchers concluded. "Given the uncertainty about how probiotics exert their effects on allergic disease, future studies investigating their modes of action are required." (Wickens K, et al. J Allergy Clin Immunol 2008;122:788-794.)