乳児のアレルギー疾患および食物過敏症の予防のためのプロバイオティクス
Abstract
Background
The composition of the intestinal microflora may be different in individuals with atopic eczema from those without this condition, and such differences may precede the development of eczema. Probiotics are live bacteria that colonize the gastrointestinal tract and provide a health benefit to the host. Probiotics added to infant feeds have the potential to prevent sensitisation of infants to dietary allergens.
Objectives
To determine the effect of probiotics given to infants for the prevention of allergic disease or food hypersensitivity.
Search methods
This included searches of the Cochrane Central Register of Controlled Trials (Issue 1, 2007), MEDLINE (1966 ‐ February 2007), EMBASE, PREMEDLINE, abstracts of conference proceedings and citations of published articles, and expert informants.
Selection criteria
Randomised and quasi‐randomised controlled trials that compare the use of a probiotic to no probiotic; or the use a specific probiotic compared to a different probiotic; or a probiotic with added prebiotic to control.
Data collection and analysis
Assessment of trial quality, data extraction and synthesis of data were performed using standard methods of the Cochrane Neonatal Review Group.
Main results
Twelve studies were eligible for inclusion. Allergic disease and / or food hypersensitivity outcomes were assessed by 6 studies enrolling 2080 infants, but outcomes for only 1549 infants were reported. Studies generally had adequate randomisation, allocation concealment and blinding of treatment. However, the findings of this review should be treated with caution due to excess losses in patient follow‐up (17% to 61%). Meta‐analysis of five studies reporting the outcomes of 1477 infants found a significant reduction in infant eczema (typical RR 0.82, 95% CI 0.70, 0.95). However, there was significant and substantial heterogeneity between studies. One study reported that the difference in eczema between groups persisted to 4 years age. When the analysis was restricted to studies reporting atopic eczema (confirmed by skin prick test or specific IgE), the findings were no longer significant (typical RR 0.80, 95% CI 0.62, 1.02). All studies reporting significant benefits used probiotic supplements containing L. rhamnosus and enrolled infants at high risk of allergy. No other benefits were reported for any other allergic disease or food hypersensitivity outcome.
Authors' conclusions
There is insufficient evidence to recommend the addition of probiotics to infant feeds for prevention of allergic disease or food hypersensitivity. Although there was a reduction in clinical eczema in infants, this effect was not consistent between studies and caution is advised in view of methodological concerns regarding included studies. Further studies are required to determine whether the findings are reproducible.
PICO
Plain language summary
乳児のアレルギー疾患および食物過敏症の予防のためのプロバイオティクス
アレルギー性疾患または食物へのアレルギー反応を予防するために、乳児食にプロバイオティクスを加えることを推奨するエビデンスは不十分である。食物へのアレルギー反応やアレルギー疾患（喘息、湿疹、花粉症など）の有病率は高く、先進国で増加している可能性がある。多くの乳児が消化管を介して乳児用調製乳などの食物による感作を受けるが、この過程は腸内細菌の組成により影響を受ける可能性がある。正常な消化管内細菌の成長を促し、食物への感作を防ぐ試みの1つとして、プロバイオティクスの使用が挙げられる。プロバイオティクスとは、消化管に定着して宿主に健康効果をもたらす生きた細菌である。今回のレビューによると、乳児食にプロバイオティクスを加えると、乳児の湿疹を防ぐ可能性がある。1つの試験はその利益が4歳まで持続するとしている。しかし、試験の質に関する懸念、試験間の結果の不一致、アレルゲンへの感作のエビデンスがある乳児に限定した場合はベネフィットが持続しなかったという事実から、これらの結果を確認するためにさらに研究が必要であると考えられる。
