Centre for MEGA Epidemiology, School of Population Health, The University of Melbourne, Melbourne, Australia.
Clin Exp Allergy. 2012 Jun;42(6):827-51. doi: 10.1111/j.1365-2222.2011.03925.x.
The relationship between breastfeeding and allergic disease risk has been controversial. This article reviews the current evidence for the role of breastfeeding in the prevention of allergic disease. We found considerable methodological limitations inherent in most studies evaluating the effect of breastfeeding in allergic disease. Nevertheless, since randomized control trials in breast feeding research would be considered unethical, the evidence remains limited to poorer quality observational studies where participation and recall bias can severely affect the objectivity of the data collected. Furthermore, reporting of type of breastfeeding (exclusive, full or partial) may be biased by a participant's inherent belief system of what they think they should be doing. Current evidence is inconclusive regarding the effect of breastfeeding on the development of eczema, with the most recent systemic review reporting no protective effect. There is insufficient data regarding the effects of breastfeeding on objective measures of food allergy at any age. Studies show a paradoxical effect of breastfeeding on the prevention of asthma, with an apparent protective effect against early wheezing illness in the first years of life yet an increased risk of asthma in later life; however, these findings must be interpreted with caution. Existing studies fail to adequately adjust for confounders, including the critical issues of protection against early life respiratory illnesses and reverse causation. Therefore, it is possible that the effect of breastfeeding on early wheezing illness reflects protection against respiratory infection, the predominant trigger of wheezing in early childhood, rather than a true reduction in risk of asthma. In summary, future research that takes into account the potential contribution of confounding factors and effect modifiers is needed to clarify the role of breastfeeding in development of allergic disease and to inform current clinical guidelines on the prevention of allergic disease.
母乳喂养与过敏疾病风险之间的关系一直存在争议。本文综述了母乳喂养在预防过敏疾病中的作用的现有证据。我们发现，评估母乳喂养对过敏疾病影响的大多数研究都存在相当大的方法学局限性。尽管如此，由于母乳喂养研究中的随机对照试验被认为是不道德的，因此证据仍然仅限于质量较差的观察性研究，其中参与和回忆偏倚可能严重影响收集数据的客观性。此外，母乳喂养类型（完全、部分或不进行母乳喂养）的报告可能会受到参与者内在信念系统的影响，他们认为自己应该怎么做。关于母乳喂养对湿疹发展的影响，目前的证据尚无定论，最近的系统性综述报告称没有保护作用。关于母乳喂养对任何年龄的食物过敏客观指标的影响，数据不足。研究表明母乳喂养对预防哮喘有矛盾的影响，在生命的头几年中，早期喘息疾病有明显的保护作用，但在以后的生活中哮喘风险增加；然而，这些发现必须谨慎解释。现有研究未能充分调整混杂因素，包括对生命早期呼吸道疾病的保护和反向因果关系等关键问题。因此，母乳喂养对早期喘息疾病的影响可能反映了对呼吸道感染的保护作用，而呼吸道感染是儿童早期喘息的主要诱因，而不是哮喘风险真正降低。总之，需要进行未来的研究，考虑混杂因素和效应修饰剂的潜在贡献，以阐明母乳喂养在过敏疾病发展中的作用，并为预防过敏疾病的当前临床指南提供信息。
