RESUMO
BACKGROUND: A mixture of neutral prebiotic oligosaccharides has been shown to reduce the incidence of atopic dermatitis (AD) and allergy associated symptoms during the first 2 years of life. OBJECTIVE: To evaluate if this protective effect against allergy lasted beyond the intervention period until 5 y of age. METHODS: In a prospective, double blind, placebo-controlled fashion, healthy term infants at risk of atopy were fed either a prebiotic-supplemented (0.8 g/100 ml scGOS/lcFOS) or placebo-supplemented (0.8 g/100 ml maltodextrin) hypoallergenic formula during the first 6 mo of life. Following this intervention period, follow-up continued until 5 y of life. The present study evaluated (i) the cumulative incidence of allergic manifestations during 5 y, and (ii) the prevalence of allergic and persistent allergic manifestations at 5 y. Monitored allergic manifestations were AD, recurrent wheezing, allergic rhinoconjunctivitis and urticaria. RESULTS: Ninety-two children (50 in placebo group, 42 in intervention group) completed the 5-y follow-up. The 5-y cumulative incidences of any allergic manifestation and atopic dermatitis were significantly lower in the scGOS/lcFOS group (30.9, 19.1 %, respectively) compared to placebo group (66, 38 %, respectively) (p< 0.01 and< 0.05). Children in the scGOS/lcFOS group tended to have a lower incidence of allergic rhinoconjunctivitis, and allergic urticaria (4.8 vs 16% for both manifestations, p=0.08). There was no difference in the cumulative incidence of recurrent wheezing. With regard to the prevalences at 5 y, intervention group had significantly lower prevalence of any persistent allergic manifestation and rhinoconjunctivitis (4.8, 2.4 %, respectively) compared to placebo (26, 14 %, respectively) (p < 0.01 and =0.05). Prevalence of persistent AD tended to be lower in the intervention group (2.4 vs 12%, p= 0.09). Although intervention group had 75% reduction in the prevalence of persistent wheezing (4.8 vs 14 %), no significance was shown. CONCLUSION: Oligosaccharide prebiotics (scGOS/lcFOS), when started early in life have a protective effect against allergic manifestations in high risk infants. The protection lasts beyond infancy until 5 y of life, for AD and allergic rhinoconjunctivitis. Long-term follow-up studies in larger populations are warranted to evaluate the potential preventive effect of this mixture on asthma.
