Mao Guang-ming, Ding Gang-qiang, Lou Xiao-ming, Zhu Wen-ming, Wang Xiao-feng, Mo Zhe, Zhou Jin-shui
Department of Environment and Occupation Health, Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou 310051, China.
Zhonghua Yu Fang Yi Xue Za Zhi. 2013 Jan;47(1):8-13.
To evaluate the iodine nutrition level of population in Zhejiang province and to analyze the relevant influencing factors from 2009 to 2011.
From October 2009 to October 2011, a total of 19 517 subjects were recruited in this cross sectional survey, by multistage stratified cluster random sampling method. The subjects were all living over three years in Zhejiang province. The basic information and life styles were interviewed by questionnaires; and the samples of drinking water, edible salt and urines were separately collected from the subjects to test the content of iodine. In total, 16 228 subjects answered the questionnaire, and 265 samples of drinking water, 7811 samples of edible salt and 19 517 samples of urine were collected. Then, we analyzed the distribution of iodine in water, edible salt and urine samples, as well as the relevance.
The median (25% - 75% percentile) of water iodine was 2.42 (1.17 - 6.28) µg/L in drinking water among Zhejiang residents; while separately 2.79 (1.60 - 6.87) µg/L in city and 2.04 (1.03 - 5.29) µg/L in country side (Z = 2.07, P < 0.05). The figures turned out to be 2.17 (1.22 - 5.73) µg/L, 2.77 (1.88 - 6.87) µg/L, and 1.40 (0.77 - 5.65) µg/L, respectively, in coastal areas, coastal periphery areas and inland areas (χ(2) = 11.16, P < 0.05). The median (25% - 75% percentile) of salt iodine was 28.80 (22.93 - 32.40) mg/kg; while separately 29.00 (24.50 - 32.60) mg/kg and 28.50 (13.90 - 32.29) mg/kg in city and country side (Z = 6.32, P < 0.05). The figures turned out to be 25.19 (0.00 - 30.20) mg/kg, 29.00 (26.60 - 31.70) mg/kg and 32.40 (28.94 - 36.30) mg/kg, respectively, in coastal areas, coastal periphery areas and inland areas (χ(2) = 1581.62, P < 0.05). The coverage rate of iodized salt was 79.54% (6213/7811) in all province. The urinary iodine median was 160.74(97.20 - 247.00) µg/L, while the urinary iodine median in pregnant women was 137.99 (82.40 - 215.30) µg/L, lower than the recommended optimal levels, which was 150 - 249 µg/L. The figures turned out to be 153.45(92.00 - 237.50) µg/L in city and 168.00 (102.18 - 257.00) µg/L in country side (Z = -9.25, P < 0.05); while in coastal, coastal periphery place and inland areas, the median were separately 156.00 (94.29 - 242.80) µg/L, 150.14 (94.70 - 227.00) µg/L and 187.70 (109.00 - 276.80) µg/L (χ(2) = 194.12, P < 0.05). The analysis of relevance between urine iodine, water iodine and iodized salt showed that the urine iodine would increase as long as the iodized salt increased; and the difference had statistical significance (χ(2) = 440.88, P < 0.01). And there were no relevance between urine iodine level and the water iodine level (χ(2)cmh = 0.57, P = 0.45). The analysis of the influencing factors showed that education background (χ(2) = 14.17, P < 0.05), different styles of career (χ(2) = 16.15, P < 0.01) and diet habits (χ(2) = 108.63, P < 0.01) could influence the level of urine iodine.
Iodine was deficient in Zhejiang province. The nutrition level of iodine was fine in Zhejiang in 2009, however, the coverage rate of iodine was commonly low in coastal areas, especially the pregnant women suffered from iodine deficiency. In our study, the factors influencing the urine iodine level included iodized salt, age, education background and diet habits.
评估2009年至2011年浙江省人群碘营养水平并分析相关影响因素。
2009年10月至2011年10月，采用多阶段分层整群随机抽样方法，共招募19517名受试者参与本次横断面调查。所有受试者均在浙江省居住超过三年。通过问卷调查获取其基本信息和生活方式；并分别采集受试者的饮用水、食用盐和尿液样本检测碘含量。共16228名受试者回答了问卷，采集了265份饮用水样本、7811份食用盐样本和19517份尿液样本。然后，分析水、食用盐和尿液样本中碘的分布情况以及相关性。
浙江省居民饮用水中碘含量中位数（25% - 75%百分位数）为2.42（1.17 - 6.28）μg/L；其中城市为2.79（1.60 - 6.87）μg/L，农村为2.04（1.03 - 5.29）μg/L（Z = 2.07，P < 0.05）。沿海地区、沿海周边地区和内陆地区分别为2.17（1.22 - 5.73）μg/L、2.77（1.88 - 6.87）μg/L和1.40（0.77 - 5.65）μg/L（χ(2)=11.16，P < 0.05）。食用盐碘含量中位数（25% - 75%百分位数）为28.80（22.93 - 32.40）mg/kg；其中城市为29.00（24.50 - 32.60）mg/kg，农村为28.50（13.90 - 32.29）mg/kg（Z = 6.32，P < 0.05）。沿海地区、沿海周边地区和内陆地区分别为25.19（0.00 - 30.20）mg/kg、29.00（26.60 - 31.70）mg/kg和32.40（(28.94 - 36.30）mg/kg（χ(2)=1581.62，P < 0.05）。全省碘盐覆盖率为79.54%（6213/7811）。尿碘中位数为160.74(97.20 - 247.00)μg/L，而孕妇尿碘中位数为137.99（82.40 - 215.30）μg/L，低于推荐的适宜水平150 - 249μg/L。城市为153.45(92.00 - 237.50)μg/L，农村为168.00（102.18 - 257.00）μg/L（Z = -9.25，P < 0.05）；沿海、沿海周边地区和内陆地区中位数分别为156.00（94.29 - 242.80）μg/L、150.14（94.70 - 227.00）μg/L和187.70（109.00 - 276.80）μg/L（χ(2)=194.12，P < 0.05）。尿碘、水碘与碘盐之间的相关性分析显示，碘盐增加尿碘也会增加；差异有统计学意义（χ(2)=440.88，P < 0.01）。尿碘水平与水碘水平之间无相关性（χ(2)cmh = 0.57，P = 0.45）。影响因素分析显示，教育背景（χ(2)=14.17，P < 0.05）、职业类型（χ(2)=16.15，P < 0.01）和饮食习惯（χ(2)=108.63，P < 0.01）可影响尿碘水平。
浙江省存在碘缺乏情况。2009年浙江省碘营养水平尚可，但沿海地区碘盐覆盖率普遍较低，尤其是孕妇存在碘缺乏情况。本研究中，影响尿碘水平的因素包括碘盐、年龄、教育背景和饮食习惯。
