VITAMIN A DEFICIENCY IN BRAZILIAN CHILDREN AND ASSOCIATED VARIABLES

ABSTRACT Objective: To analyze the variables associated with vitamin A deficiency (VAD) in Brazilian children aged 6 to 59 months, considering a hierarchical model of determination. Methods: This is part of the National Survey on Demography and Health of Women and Children, held in 2006. Data analysis included 3,417 children aged from six to 59 months with retinol data. Vitamin A deficiency was defined as serum retinol <0.7 mol/L. Univariate and multiple Poisson regression analysis were performed, with significance level set at 5%, using a hierarchical model of determination that considered three conglomerates of variables: those linked to the structural processes of community (socioeconomic-demographic variables); to the immediate environment of the child (maternal variables, safety and food consumption); and individual features (biological characteristics of the child). Data were expressed in prevalence ratio (PR). Results: After adjustment for confounding variables, the following remained associated with VAD: living in the Southeast [PR=1,59; 95%CI 1,19-2,17] and Northeast [PR=1,56; 95%CI 1,16-2,15]; in urban area [RP=1,31; 95%CI 1,02-1,72]; and mother aged ≥36 years [RP=2,28; 95%CI 1,37-3,98], the consumption of meat at least once in the last seven days was a protective factor [PR=0,24; 95%CI 0,13-0,42]. Conclusions: The main variables associated with VAD in the country are related to structural processes of society and to the immediate, but not individual, environment of the child.

摘要
目的：本研究采用层级确定模型，分析巴西6至59月龄儿童维生素A缺乏症（vitamin A deficiency, VAD）的相关影响变量。
方法：本研究为2006年开展的全国妇女与儿童人口与健康调查的子研究。数据分析纳入3417名具备血清视黄醇检测数据的6至59月龄儿童。维生素A缺乏症定义为血清视黄醇浓度＜0.7 μmol/L（注：原文标注为mol/L，结合临床检测常规应为μmol/L）。本研究采用显著性水准设定为5%的单因素与多因素泊松回归分析，并构建层级确定模型，将研究变量划分为三类：与社区结构进程相关的社会人口统计学变量；与儿童直接生活环境相关的母亲相关变量、健康安全状况与膳食消费变量；以及儿童个体生物学特征变量。研究数据以患病率比（prevalence ratio, PR）进行表达。
结果：在校正混杂变量后，以下因素仍与维生素A缺乏症显著相关：居住于巴西东南部[PR=1.59；95%CI 1.19-2.17]及东北部[PR=1.56；95%CI 1.16-2.15]；居住于城市地区[PR=1.31；95%CI 1.02-1.72]；母亲年龄≥36岁[PR=2.28；95%CI 1.37-3.98]；近7日内至少食用一次肉类为保护因素[PR=0.24；95%CI 0.13-0.42]。（注：原文此处标注为RP，结合前文统一修正为PR）
结论：巴西该年龄段儿童维生素A缺乏症的主要相关影响因素与社会结构进程及儿童直接生活环境相关，而非儿童个体特征。