我国4城市学龄前儿童血清维生素B_(12)营养状况调查

目的了解我国学龄前儿童血清维生素B12(VB12)的营养状况。方法描述性流行病学研究;对来自北京、珠海、重庆、武汉4城市2002名2岁～7岁儿童进行体格检查、膳食调查、血常规筛查及血清VB12水平测定。结果⑴2002名儿童平均血清VB12水平为775pg/ml,市区(835pg/ml)高于郊区(720pg/ml,P<0.001),其中北京840pg/ml、珠海772pg/ml、重庆756pg/ml、武汉735pg/ml,地区间差异显著(P<0.001);⑵学龄前儿童平均血清VB12水平在各年龄组间有明显差异(P<0.05),无性别差异(P>0.05);⑶2002名儿童血清VB12缺乏(血清VB12<200pg/ml)检出率为1.5%,边缘性缺乏(血清VB12200pg/ml～300pg/ml)检出率为3.2%,市区儿童血清VB12缺乏和边缘性缺乏检出率(3.6%)低于远郊(5.9%,P<0.05)。其中北京、珠海、重庆、武汉4城市儿童血清VB12缺乏和边缘性缺乏检出率分别为0.4%、3.5%,0.2%、3.0%,0.2%、1.9%,5.2%、4.6%;⑷儿童血清VB12水平主要受膳食VB12摄入量的影响(P<0.001)。2002名儿童平均膳食VB12摄入量为2.2μg/d,市区(2.4μg/d)高于郊区(2.0μg/d,P<0.05)。北京、珠海、重庆、武汉4城市儿童平均膳食VB12摄入量分别为2.8、2.6、1.9、1.6μg/d,差异显著(P<0.001)。结论⑴我国学龄前儿童存在VB12缺乏,以边缘性缺乏为主。⑵学龄前儿童血清VB12水平高于成人,血清VB12水平有随年龄增长而降低的趋势,提示血清VB12水平存在年龄差异。⑶学龄前儿童膳食VB12摄入量的高低决定血清VB12水平的高低。     

银川市中小学生维生素D营养状况及影响因素

了解银川6~18岁儿童青少年的维生素D营养状况及其影响因素,为改善儿童青少年维生素D营养状况提供理论依据.方法 采用分层整群随机抽样方法,从银川市抽取小学、初中、高中各2所共36个班1 615名学生作为调查对象,进行静脉采血、体格检查和问卷调查.结果 学生维生素D缺乏率和适宜率分别为66.9%和33.1%,不同年龄组间维生素D缺乏率差异有统计学意义(x2=25.65,P<0.05),6岁组最高(79.2%),其次为13岁组(76.6%)和12岁组(75.3%).二元Logistic回归分析结果显示,影响儿童青少年维生素D营养状况的因素有年龄(OR=0.95)、每日户外运动时间(OR=0.49)、纯母乳喂养(OR=0.63)和母亲学历(高中及大专、本科及以上的OR值分别为0.73,0.43);决策树QUEST和Logistic回归组合模型结果显示,影响儿童青少年维生素D营养状况的关键因素有每日户外运动时间、年龄、母亲学历、体质量指数(BMI)以及户外运动时间和年龄、户外运动时间和母亲学历、年龄和母亲学历、纯母乳喂养和BMI之间的交互作用.结论 银川学生维生素D营养状况不良检出率较高,影响维生素D营养状况的关键因素有每日户外运动时间、年龄、母亲学历、BMI以及户外运动时间和年龄、户外运动时间和母亲学历、年龄和母亲学历、纯母乳喂养和BMI之间的交互作用.     

松滋市0～6岁儿童血清25-羟基维生素D水平调查

目的调查及评价松滋市0～6岁儿童体内维生素D水平,为该地区制定预防儿童维生素D缺乏的措施提供参考。方法选取2016-2017年于湖北省某医院出生以及接受体检的189名0～6岁儿童作为研究对象,检测其血清中25-羟基维生素D水平,同时采用半定量食物频率问卷对研究对象30d内的饮食情况进行调查。结果研究对象血清25-羟基维生素D水平为(16.13±7.69)ng/mL,其中25-羟基维生素D营养状况为严重缺乏的有25例(13.22%),缺乏的有60例(31.75%),不足的有45例(23.81%),正常的有59例(31.22%)。年龄1岁的研究对象25-羟基维生素D营养状况为严重缺乏的人数比例为13.64%,1～2岁的研究对象25-羟基维生素D营养状况为严重缺乏的人数比例为14.00%,2～6岁的研究对象25-羟基维生素D营养状况为严重缺乏的人数比例为10.34%。年龄1岁的研究对象维生素D补充剂添加率为90.91%,高于1～2岁研究对象的68.00%及2～6岁研究对象的41.38%(P0.05)。此外,年龄1岁、1～2岁及2～6岁的研究对象其膳食维生素D摄入量与儿童维生素D推荐摄入量的比值≤40%的人数比例分别为6.36%,10.00%及13.79%。结论松滋市0～6岁儿童维生素D水平较低,维生素D缺乏普遍。建议对该地区维生素D缺乏的儿童进行膳食干预。此外,加大在学校开展维生素D等营养素相关知识的健康宣教力度,增加学生的户外活动,以降低该地区儿童的维生素D缺乏率。     

武汉市5岁以下儿童维生素A营养状况及其影响因素研究

[目的]了解武汉市5岁以下儿童维生素A营养状况及其影响因素,为制定相应干预措施提供依据。[方法]分层整群抽取武汉市5个中心城区和2个远城区的1270名0～5岁儿童进行问卷调查和血清维生素A含量测定。[结果]5岁以下儿童血清维生素A水平为(1.87±0.77)μmol/L。亚临床维生素A缺乏症发生率为3.39%,可疑亚临床维生素A缺乏症发生率为7.32%。维生素A缺乏在各年龄组之间有统计学差异,性别之间差异无统计学意义。母亲文化程度、家庭人均收入、近1周食用乳、蛋等、近1月服用维生素A制剂、2周内患呼吸系统疾病和腹泻是亚临床维生素A缺乏的影响因素。[结论]亚临床维生素A缺乏是5岁以下儿童维生素A缺乏的主要表现形式,建议将亚临床维生素A缺乏的预防和干预纳入儿童保健工作常规。     

6651例0岁～16岁儿童维生素D营养状况调查分析

目的了解0岁~16岁儿童维生素D营养状况及其与年龄、性别、季节的关系,为本地区儿童合理补充维生素D提供科学依据。方法对2012年4月-2014年11月来温州医科大学附属第二医院育英儿童医院保健科体检的0岁~16岁6 651例儿童,采用电化学发光法进行血清25-羟维生素D水平检测。结果 6 651例儿童25-羟维生素D水平为(29.63±12.83)ng/ml,其中25-羟维生素D严重缺乏组92例(1.38%),缺乏组1 498例(22.52%),不足组2 434例(36.60%),充足组2 627例(39.50%)。0~岁组和1~岁组儿童血清25-羟维生素D水平明显高于其他年龄组,差异有统计学意义(P0.05),3岁后儿童血清25-羟维生素D水平明显下降,各年龄组间差异有统计学意义(P0.01)。不同性别间血清25-羟维生素D水平差异无统计学意义(t=1.373,P0.05)。不同季节儿童血清25-羟维生素D水平秋季最高,夏季最低。结论 0岁~16岁儿童25-羟维生素D水平低下,应增加该地区儿童的维生素D摄入量,尤需加强6岁以上儿童维生素D的补充及夏季儿童的户外活动。     

0～9岁儿童维生素D水平的调查

目的了解儿童维生素D的营养状况。方法对绍兴市妇幼保健院儿童保健科门诊进行体检的0~9岁952名儿童,进行血清25-(OH)维生素D水平检测,分析不同性别、年龄和季节儿童维生素D水平。结果 0~9岁儿童25-(OH)维生素D的平均测定值为(29.78±12.08)ng/L;其中25-(OH)维生素D严重缺乏占2.63%;缺乏占18.80%;不足占32.77%。不同年龄组儿童的25-(OH)维生素D水平不同(P0.01),男、女童血清25-(OH)维生素D水平比较,差异无统计学意义(P0.05)。夏秋季体检儿童的血清25-(OH)维生素D水平高于春冬季体检儿童(P0.05)。结论绍兴市城区0~9岁儿童25-(OH)维生素D水平低下,应增加儿童的维生素D摄入量及加强户外活动,尤需重视4~9岁的儿童及冬春季节维生素D的补充。     

血清维生素B12水平对产妇及新生儿IGF2 DNA甲基化的影响

目的评价健康产妇血清维生素B12水平对胎儿甲基化状态的影响。方法对河南省侯寨乡中心卫生院80例临产产妇进行回顾性健康问卷调查;采用顺磁性颗粒化学发光免疫法测定血清维生素B12含量;real time-PCR分析IGF2 P2、P3启动子区甲基化状态。结果母亲与脐血血清维生素B12水平分别为167.68 pg/m L和205.98 pg/m L,两组之间差异具有统计学意义(P0.05)。母血IGF2 P2甲基化率均值为3.03%,脐血3.84%,脐血IGF2 P2甲基化率高于母血IGF2 P2甲基化率(P0.05)。母血IGF2 P3甲基化率均值为5.58%,脐血为4.35%,母血IGF2 P3甲基化率高于脐血IGF2 P3甲基化率(P0.05)。脐血IGF2 P3的甲基化状态与母血IGF2P3的甲基化状态呈正相关(β=0.423,P=0.000 5),同时与母血维生素B12水平呈负相关(β=-0.211,P=0.006 9),与母亲受教育程度呈正相关(β=0.185,P=0.038)。母血IGF2 P2的甲基化状态与母血维生素B12水平呈负相关(β=-0.213,P=0.016),与母亲被动吸烟(β=0.310,P=0.022)和孕期增重(β=0.362,P=0.019)呈正相关。结论环境因素可影响母亲外周血及脐血DNA甲基化水平。     

强化挂面改善学龄前儿童营养状况的实验观察

目的 了解儿童营养强化挂面对改善学龄前儿童营养状况的效果。方法 采用称重法对某幼儿园儿童进行膳食调查,并测定尿中维生素B1、维生素B2及维生素C营养水平。结果：儿童膳食中最易缺乏的维生素A、维生素B1、维生素B2的摄入量有明显的6提高。实验前、后尿中维生素B1、维生素B2、维生素C营养水平差异具有显性（P＜0.01）。结论：该产品对改善儿童维生素A、维生素B1、维生素B2营养状况作用明显,是一种值得推广的儿童食品。     

包头地区0～6岁儿童25羟基维生素D水平调查分析

目的调查内蒙古自治区包头地区0～6岁儿童25羟基维生素D水平,以了解其维生素D营养状况。方法以整群抽样方法选择2016年2月—2017年2月包头地区5家医院2 952例0～6岁体检儿童,以酶联免疫吸附法测定其血清25羟基维生素D水平,统计其血清25羟基维生素D整体水平及维生素D营养状态,对比不同性别、不同年龄及不同季节时儿童血清25羟基维生素D水平与维生素D营养状态,并分析性别、年龄与季节与维生素D缺乏的相关性。结果受检儿童血清25羟基维生素D平均水平为(68.02±6.95)nmol/L;其中维生素D过量12例,占0.41%;维生素D充足936例,占31.71%;维生素D不足1 155例,占39.13%;维生素D缺乏747例,占25.30%;维生素D严重缺乏102例,占3.46%,维生素D不足、缺乏、严重缺乏的总检出率为67.89%。男女童血清25羟基维生素D水平、维生素D营养状态相比,差异均无统计学意义;2岁年龄≤4岁及4岁年龄≤6岁儿童血清25羟基维生素D水平明显低于年龄1岁及1岁≤年龄≤2岁婴幼儿,且维生素D充足人数比例低于年龄1岁及1岁≤年龄≤2岁婴幼儿,缺乏与严重缺乏人数比例高于年龄1岁及1岁≤年龄≤2岁婴幼儿,差异均有统计学意义;4岁年龄≤6岁儿童维生素D严重缺乏人数比例亦高于2岁年龄≤4岁儿童,差异有统计学意义;夏秋季儿童的血清25羟基维生素D水平高于春冬季,且维生素D充足人数比例高于春冬季,缺乏人数比例低于春冬季,差异均有统计学意义。通过Spearman相关性分析显示,年龄与维生素D缺乏呈显著正相关,季节与维生素D缺乏呈显著负相关(P均0.05);性别与维生素D缺乏无明显相关性。结论包头地区0～6岁儿童25羟基维生素D水平较低,维生素D缺乏现象较为严重,且其与季节、儿童年龄等具有密切关系,应适当增加本地区儿童维生素D摄入量与户外活动量,特别需重视春冬季时及年龄≥3岁儿童血清25羟基维生素D水平检测与维生素D的补充。     

太原市1050名0～14岁儿童维生素D营养状况调查

目的了解太原市1 050名0～14岁健康儿童维生素D营养状况。方法回顾性分析2016年9月至2017年8月在太原市妇幼保健院儿保科门诊进行常规体检的1 050名健康儿童的25-(OH)D水平,分析不同性别、年龄、季节维生素D营养状况。结果太原市1 050名0～14岁儿童25-(OH)D平均水平为(31.04±10.42)ng/ml,男女童差异无统计学意义(P0.05)。随年龄增长维生素D水平逐渐下降,不同年龄组儿童维生素D水平差异有统计学意义(P0.01),6～14岁儿童维生素D水平最低(23.13±7.70)ng/ml。随年龄增加维生素D缺乏与不足逐渐上升(P0.01),2岁以下儿童无缺乏。春季儿童维生素D水平最低(26.25±9.53)ng/ml,冬春季维生素D缺乏与不足高于夏秋季(P0.01)。结论太原市1 050名儿童中2岁婴幼儿维生素D营养状况良好,2岁儿童在冬春季维生素D缺乏与不足问题值得关注。     

2009年北京市顺义区4～12月龄婴幼儿母乳喂养与辅食添加情况

目的了解北京市农村1岁之内婴幼儿母乳喂养及辅食添加情况,为政府制定政策提供依据。方法采取分层整群随机抽样方法,在顺义区4个乡镇抽取北京市户口4～12月龄婴幼儿136名,在知情同意后,进行连续入户2日或4日面对面调查。结果顺义区婴幼儿4月龄内完全母乳喂养、部分母乳喂养及人工喂养率分别为43.4%、44.6%、11.8%;73.9%的婴幼儿在4～6个月添加了辅食,大部分添加3种以上,最先添加为谷类和蛋类,然后为果蔬类,肉豆类添加较晚。结论应加强对乳母及未生育妇女的健康教育,提高4月龄内完全母乳喂养率,适时添加各类辅食。     

待产女性血清维生素B12和叶酸水平的流行病学特征

目的 分析陕西省待产女性维生素B₁₂和叶酸水平及两者间关系的流行病学特征。方法 资料来源于2014年1月至2016年12月在6所三甲医院待产的健康孕妇,产前采集血样以测定维生素B₁₂和叶酸水平。采用分位数回归模型分析待产女性维生素B₁₂和叶酸水平间的关系。结果 共纳入1 277名待产女性,其血清维生素B₁₂的中位数为164.7 pg/ml,缺乏率为69.6%,血清叶酸的中位数为7.6 ng/ml,缺乏率为12.1%,单纯缺乏维生素B₁₂者占58.4%,单纯缺乏叶酸者占0.9%。农村待产女性维生素B₁₂和叶酸水平低于城市女性,维生素B₁₂和叶酸水平随年龄的增长而呈不同幅度增加,<25岁者维生素B₁₂和叶酸水平明显较低。叶酸缺乏者的维生素B₁₂水平比非缺乏者平均低37.62 pg/ml,分位数回归模型显示,在不同的维生素B₁₂分位点上,叶酸缺乏者的维生素B₁₂水平明显低于不缺乏者,且这种差异随着维生素B₁₂水平的升高而增大。结论 陕西省待产女性维生素B₁₂和叶酸缺乏症仍普遍存在,在妇幼保健实践中,叶酸增补的同时可能需重视维生素B₁₂补充。加大健康教育力度,重点提高农村和年轻女性对营养素补充重要性的认识,从而改善其维生素B₁₂和叶酸水平。     

Dietary Intake and Milk Micronutrient Levels in Lactating Women with Full and Partial Breastfeeding

Background

Micronutrient intake and status in lactating women may impact micronutrient levels in milk.

Objectives

This study aimed to determine the micronutrient intake and status in lactating women, and their association with micronutrient levels in human milk.

Methods

Lactating women were enrolled at 4–6 months postpartum. A 24h food recall was examined and nutrient intakes were analyzed using INMUCAL software. Human milk samples were collected to analyze calcium, copper, iron, and zinc levels. Plasma zinc and serum ferritin levels were determined.

Results

Thirty-four women participated; 19 were classified as full breastfeeding and 15 as partial breastfeeding. Mean levels of calcium, copper, iron, and zinc in human milk were 243, 0.2, 0.2, and 1.56 mg/L, respectively. The prevalence of zinc deficiency (plasma zinc?<?10.7 µmol/L) was 11.8%. No lactating women had iron deficiency. Nutrient intakes were lower than the recommended amounts in 38%–70% of participants, and were not correlated with corresponding nutrient levels in human milk. Multiple linear regression showed significant association between zinc levels in human milk and plasma for lactating women with full breastfeeding (β?=?0.034, 95% confidence interval [0.003, 0.067], p?=?0.040).

Conclusions

Lactating women were at risk of micronutrient deficiency. There was an association between zinc levels in human milk and plasma of lactating women with full breastfeeding. As the nutritional status of lactating women influences the quality of human milk, we should encourage good nutrient intake for lactating women.

     

乌市水区新生儿脐血与孕母血维生素D水平的相关性及其影响因素

目的了解新生儿脐带血与孕母妊娠末期血维生素D水平的相关性,探讨影响新生儿脐血维生素D水平的相关因素。方法对自2015年11月-2016年3月冬季收住的112例新生儿脐血及其中40例的孕母产前静脉血采用化学发光法测定维生素D值,进行相关性分析。结果 112例新生儿脐血25(OH)D平均水平为(6.75±3.59)ng/ml,新生儿维生素D均处于缺乏状态,中、重度维生素D缺乏新生儿占85.7%。40例孕母血25(OH)D平均水平与新生儿血25(OH)D水平呈显著正相关(r=0.86,P0.001);孕妇的民族、孕期补钙时间、海产品摄入次数与孕妇文化程度等对新生儿维生素D水平的影响有统计学意义;孕妇不同孕周、工作类型、户外活动时间、孕期是否抽筋及新生儿胎产次、胎儿性别、出生方式等对新生儿维生素D水平的影响无统计学意义(P0.05)。结论冬季出生的新生儿维生素D缺乏严重,与孕妇妊娠末期静脉血维生素D水平显著相关。冬季应给予孕晚期孕妇补充足量维生素D,以提高新生儿维生素D水平。     

Breast milk vitamin B-12 concentrations in Guatemalan women are correlated with maternal but not infant vitamin B-12 status at 12 months postpartum

In our previous studies, one-third of lactating Guatemalan women, infants, and children had deficient or marginal serum vitamin B-12 concentrations. Relationships among maternal and infant status and breast milk vitamin B-12, however, have not, to our knowledge, been investigated in such populations. Our purpose was to measure breast milk vitamin B-12 in Guatemalan women with a range of serum vitamin B-12 concentrations and explore associations between milk vitamin B-12 concentrations and maternal and infant vitamin B-12 intake and status. Participants were 183 mother-infant pairs breastfeeding at 12 mo postpartum. Exclusion criteria included mother <17 y, infant <11.5 or >12.5 mo, multiple birth, reported health problems in mother or infant, and mother pregnant >3 mo. Data collected on mothers and infants included anthropometry, serum and breast milk vitamin B-12, and dietary vitamin B-12. Serum vitamin B-12 concentrations indicated deficiency (<150 pmol/L) in 35% of mothers and 27% of infants and marginal status (150-220 pmol/L) in 35% of mothers and 17% of infants. In a multiple regression analysis, breast milk vitamin B-12 concentration was associated (P < 0.05) with both maternal vitamin B-12 intake (r = 0.26) and maternal serum vitamin B-12 (r = 0.30). Controlling for the number of breastfeeds per day and vitamin B-12 intake from complementary foods, infant serum vitamin B-12 was associated with maternal serum vitamin B-12 (r = 0.31; P < 0.001) but not breast milk vitamin B-12, implicating a long-term effect of pregnancy status on infant vitamin B-12 status at 12 mo postpartum.     

Nutritional factors associated with anaemia in pregnant women in northern Nigeria

This study was conducted to assess the relative contribution of iron, folate, and B 12 deficiency to anaemia in pregnant women in sub-Saharan Africa. In total, 146 pregnant women, who attended two antenatal clinics in Gombe, Nigeria, were recruited into the study. The majority (54%) of the women were in the third trimester. Blood samples were obtained for determination of haematocrit and for measurement of serum iron, total iron-binding capacity, ferritin, folate, vitamin B12, and homocysteine. Malaria was present in 15 (9.4%) women. Based on a haemoglobin value of<105 g/L, 44 (30%) women were classified as anaemic. The major contributing factor to anaemia was iron deficiency based on the serum concentration of ferritin (<10 ng/mL). The mean homocysteine concentration for all subjects was 14.1 pmol/L, and homocysteine concentrations were inversely correlated with concentrations of folate and vitamin B 12. The serum homocysteine increased markedly at serum vitamin B12 levels below 250 pmol/L. The most common cause of anaemia in the pregnant women in northern Nigeria was iron deficiency, and the elevated concentrations of homocysteine were most likely due to both their marginal folate and vitamin B12 status.     

High frequency of maternal vitamin B12 deficiency as an important cause of infantile vitamin B12 deficiency in Sanliurfa province of Turkey

Summary Background Vitamin B₁₂ deficiency in infancy may cause failure to thrive, severe neurological disorders and megaloblastic pancytopenia. It is well known that infants born with deficient vitamin B₁₂ storage have increased the risk of vitamin B₁₂ deficiency. Vitamin B₁₂ deficiency is more prevalent in infancy in Sanliurfa province (at the southeast region of Turkey). Aim of the study The aim of this study was to determine the frequencies of vitamin B₁₂, folic acid and iron deficiencies in pregnants and their babies at birth and to what extend the mothers’ deficiency becomes effective on babies’ deficiencies. Methods The study groups were constituted by 180 pregnant women and their single and term babies. Venous blood samples of pregnants were obtained 1–3 h before delivery and babies’ cord bloods were collected at birth. Vitamin B₁₂ and folic acid levels were measured with electro chemiluminiscence method; serum iron and iron binding capacities were measured by colorimetric method and complete blood counts were performed by automatic blood counter. Results Mean vitamin B₁₂ levels in maternal and cord blood serum were 130 ± 61.7 pg/ml and 207 ± 141 pg/ml; mean folic acid levels were 8.91 ± 6.46 ng/ml and 17.8 ± 11.8 ng/ml; mean serum iron levels were 56.9 ± 37.5 μg/dl and 147 ± 43.2 μg/dl; and mean transferrin saturations were 11.8 ± 8% and 65.6 ± 24%, respectively. There were vitamin B₁₂ deficiency (<160 pg/ml) in 72% of the mothers and 41% of the babies, and severe deficiency (<120 pg/ml) in 48% of the mothers and 23% of the babies. Folic acid deficiency was found in 12% of the mothers, but was not found in the babies. There were iron deficiency in 62% of the mothers and 1% of the babies. There were statistically significant correlation between maternal and cord blood serum vitamin B₁₂ levels (r = 0.395, P < 0.001) and folic acid levels (r = 0.227, P = 0.017), while there were no correlation between maternal and cord blood iron levels and transferrin saturations. Conclusion The study results showed that vitamin B₁₂ deficiency is prevalent in pregnants in this region and that 41% of infants have born with deficient vitamin B₁₂ storages. Therefore, prophylactic use of vitamin B₁₂ by pregnant women in Sanliurfa and other poor communities could have considerable benefits to prevent vitamin B₁₂ deficiency and its complications in infants.     

High prevalence of folic acid and vitamin B12 deficiencies in infants, children, adolescents and pregnant women in Venezuela

BACKGROUND: There is increased worldwide concern about the consequences of folic acid and vitamin B12 deficiencies on health, which include megaloblastic anemia, neural tube defects and cardiovascular disease. OBJECTIVE: This study intended to determine the prevalence of folic acid and vitamin B12 deficiencies in vulnerable groups in labor and poor socioeconomic strata of the Venezuelan population. METHODS: A total of 5658 serum samples were processed to determine folic acid and vitamin B12 concentrations. The study involved three surveys performed during 2001-2002 and included infants, children, adolescents and pregnant women from labor and poor socioeconomic strata of the population. The method used was a radio immunoassay designed for the simultaneous measurement of serum folic acid and vitamin B12. RESULTS: The prevalence of folic acid deficiency was higher than 30% for all groups studied, reaching 81.79% in adolescents. Vitamin B12 deficiency was 11.4% in samples collected nationwide, but there was also a similar prevalence of high serum levels. The prevalence of folic acid and vitamin B12 deficiencies in pregnant women reached 36.32 and 61.34%, respectively. CONCLUSION: This work shows that there is a high prevalence of folic acid deficiency, especially in women of reproductive age, pregnant adolescents and in the whole population studied in Vargas state. This situation requires immediate intervention as supplementation or food fortification programs.     

西藏自治区六岁以下儿童维生素A缺乏情况调查

目的 了解西藏自治区6岁以下儿童维生素A缺乏(VAD)情况。方法 采用分层整群随机抽样方法,将西藏分为城市、牧业县、农业县、半农半牧县4层,每层抽2个市或县进行调查。调查内容包括家庭一般状况、儿童喂养和疾病情况,收集儿童血清。血清维生素A(VA)含量检测采用微量荧光法。结果 共调查6岁以下儿童1257人,男635人,女622人,藏族占98．8％。2岁以上儿童836人,发现儿童夜盲症6例,结膜干燥症2例,儿童临床VAD患病率为0．96％。在1071名接受调查的母亲中,夜盲症18例(1．7％)。4类地区均发现有临床VAD病例。西藏儿童VA平均水平为1．09μmol／L,城市儿童(1．15μmol／L)和牧业县儿童(1．12μmol／L)显著高于农业县儿童(1．04μmol／L)和半农半牧县儿童(1．05μmol／L)。儿童亚临床VAD(血清VA≤0．70μmol／L)患病率：城市、牧业县、农业县和半农半牧县儿童分别为5．4％、4．7％、11．0％和12．3％,差异有显著性;0．5岁以下和0．5岁以上婴儿组亚临床VAD患病率分别为22．2％和13．3％,显著高于1岁以上各年龄组儿童(1岁为8．5％,2～3岁为5．4％,4～5岁为7．9％);男女儿童血清VA水平和亚临床VAD患病率的差异无显著性。结论 西藏儿童VAD情况较全国为轻,但农业县和半农半牧县属于中度亚临床VAD地区,需要对这些地区的儿童,特别是1岁以下的婴儿补充VA。