HarvestPlus, International Food Policy Research Institute, 2033 K Street NW, Washington, DC 20006, USA.
Public Health Nutr. 2012 Sep;15(9):1688-96. doi: 10.1017/S1368980012000924. Epub 2012 Mar 23.
To determine the prevalence of vitamin A deficiency, infection and adequacy of vitamin A intakes among Zambian children, and the contribution of dietary vitamin A and infection to vitamin A status.
A cross-sectional survey of vitamin A intakes by the 24 h recall method, vitamin A status by plasma retinol and the modified relative dose-response test, and infection by acute-phase proteins.
Rural communities in Central and Eastern Provinces of Zambia.
Children 2-5 years of age.
The prevalence of vitamin A deficiency was 56 % by plasma retinol, 48 % with infection-adjusted plasma retinol and 22 % by the modified relative dose-response test. The majority of children (61 %) had a current infection. Vitamin A intakes were relatively high (331 to 585 μg retinol activity equivalents/d in the harvest/early post-harvest and late post-harvest seasons, respectively) and the prevalence of inadequate intakes was <1 % when compared with the Estimated Average Requirement (210 and 275 μg retinol activity equivalents/d for children aged 1-3 and 4-8 years, respectively). Elevated α-1-acid glycoprotein was negatively associated with plasma retinol (P < 0·0 0 1) and vitamin A intake was positively associated with plasma retinol (P < 0·05), but only when estimated assuming a 26:1 retinol equivalence for provitamin A from green and yellow vegetables.
Infection and vitamin A intakes were significant determinants of plasma retinol. We cannot conclude which indicator more accurately represents the true vitamin A status of the population. Reasons for the persistent high prevalence of vitamin A deficiency in the presence of adequate vitamin A intakes are unclear, but the high rates of infection may play a role.
确定赞比亚儿童维生素 A 缺乏、感染和维生素 A 摄入量的充足程度，以及饮食中维生素 A 和感染对维生素 A 状况的影响。
通过 24 小时回忆法评估维生素 A 摄入量、血浆视黄醇和改良相对剂量反应试验评估维生素 A 状态、急性蛋白评估感染的横断面调查。
赞比亚中东部省份的农村社区。
2-5 岁儿童。
根据血浆视黄醇，维生素 A 缺乏的流行率为 56%，调整感染后血浆视黄醇为 48%，改良相对剂量反应试验为 22%。大多数儿童（61%）有当前感染。维生素 A 摄入量相对较高（收获/早收获后和晚收获后季节分别为 331 至 585μg 视黄醇活性当量/d），与估计平均需求量（分别为 1-3 岁和 4-8 岁儿童 210 和 275μg 视黄醇活性当量/d）相比，摄入量不足的流行率<1%。α-1-酸性糖蛋白升高与血浆视黄醇呈负相关（P<0·001），维生素 A 摄入量与血浆视黄醇呈正相关（P<0·05），但仅在假设来自绿色和黄色蔬菜的前维生素 A 以 26:1 的视黄醇当量估计时才成立。
感染和维生素 A 摄入量是血浆视黄醇的重要决定因素。我们不能确定哪个指标更能准确反映人群的真实维生素 A 状况。在存在充足维生素 A 摄入量的情况下，维生素 A 缺乏持续高流行的原因尚不清楚，但高感染率可能起作用。
