Vitamin A deficiency and associated factors in children in urban areas

OBJECTIVE To estimate the prevalence of vitamin A deficiency and its associated factors in children. METHODS A cross-sectional population-based study, involving 1,211 children of both sexes, aged between six and 59 months old, was carried out in the urban zone of 9 cities in the state of Paraiba, Northeastern Brazil. Vitamin A status was assessed by serum retinol levels (high performance liquid chromatography – HPLC) and subclinical infection was assessed by C-reactive protein concentrations. Socioeconomic, demographic and sanitation conditions, as well as vitamin A supplement intake, were also evaluated. Children with serum retinol concentrations RESULTS The prevalence of vitamin A deficiency was 21.8% (95%CI 19.6;24.2), showing an association with subclinical infection and lack of indoor plumbing. The prevalence of vitamin A deficiency was 21.8% (95%CI 19.6;24.2). After adjustment, vitamin A deficiency was found to be linked with subclinical infection and lack of indoor plumbing. Vitamin A deficiency was four times higher (CI95% 1.49;10.16) in children with subclinical infection whose homes were without indoor plumbing, compared to children who were not infected and with indoor plumbing in their homes. CONCLUSIONS Despite activities aimed at the prevention and control of vitamin A deficiency, hypovitaminosis A, remains a public health concern among children under five.

研究目的：评估儿童维生素A缺乏症的患病率及其相关影响因素。
研究方法：本研究为基于人群的横断面研究，于巴西东北部帕拉伊巴州（Paraiba）9座城市的城区开展，共纳入1211名6至59月龄的男女儿童。采用血清视黄醇水平（高效液相色谱法，high performance liquid chromatography，HPLC）评估维生素A营养状况，通过C反应蛋白浓度检测亚临床感染情况。同时收集研究对象的社会经济、人口学、卫生设施状况以及维生素A补充剂摄入情况等相关信息。
研究结果：儿童维生素A缺乏症的患病率为21.8%（95%置信区间19.6；24.2），其与亚临床感染及室内管道供水缺失存在关联。经校正分析后发现，维生素A缺乏症仍与亚临床感染、室内管道供水缺失显著相关。与未发生感染且家中具备室内管道供水的儿童相比，存在亚临床感染且家中无室内管道供水的儿童，其维生素A缺乏症患病率高出4倍（95%置信区间1.49；10.16）。
研究结论：尽管已开展针对维生素A缺乏症的预防与控制工作，但维生素A缺乏症（hypovitaminosis A）仍是5岁以下儿童群体中亟待关注的公共卫生问题。