Murguía Peniche María Teresa
Infancy Area, National Center for Child and Adolescent Health, Mexico City, Mexico.
Nestle Nutr Inst Workshop Ser. 2012;70:91-102. doi: 10.1159/000337447. Epub 2012 Aug 31.
Vitamin A deficiency is common in the developing world. Vitamin A supplementation (VAS) has been used to prevent or treat vitamin A deficiency and to decrease mortality and morbidity in children. However, there are still controversial issues in relation to the role of universal VAS in different populations. Thus, studies that look at mortality outcomes reveal that VAS decreases mortality in children >6 months of age; however, there is still controversy on the extent to which reduction in morbidity from diarrhea and respiratory infection, other than measles, decreases mortality. Studies in infants 1-5 months old show no protective effect of VAS on mortality; whether this is secondary to environmental influences (breastfeeding), or interactions with DTP vaccine, needs to be further investigated. Studies with VAS in newborns have resulted in contrasting results in countries in Africa and Asia; trials are underway to better understand this. VAS does not have a universal protective effect on lower respiratory tract infection in children; some studies reveal an increase in respiratory morbidity associated with VAS, especially in well-nourished children; in contrast, VAS may confer some protection to malnourished children. The interaction of VAS with different vaccines is under current debate; some discussions are presented.
维生素A缺乏在发展中国家很常见。维生素A补充剂（VAS）已被用于预防或治疗维生素A缺乏，并降低儿童的死亡率和发病率。然而，关于普遍使用VAS在不同人群中的作用仍存在争议问题。因此，观察死亡率结果的研究表明，VAS可降低6个月以上儿童的死亡率；然而，除麻疹外，腹泻和呼吸道感染发病率的降低在多大程度上能降低死亡率仍存在争议。对1至5个月大婴儿的研究表明，VAS对死亡率没有保护作用；这是继发于环境影响（母乳喂养）还是与百白破疫苗的相互作用，有待进一步研究。在非洲和亚洲国家，对新生儿使用VAS的研究结果相互矛盾；目前正在进行试验以更好地理解这一点。VAS对儿童下呼吸道感染没有普遍的保护作用；一些研究表明，VAS会增加呼吸道发病率，尤其是在营养良好的儿童中；相反，VAS可能会给营养不良的儿童提供一些保护。VAS与不同疫苗的相互作用目前正在讨论中；本文给出了一些讨论内容。
