2011年广东省碘缺乏病监测结果分析

Data analysis of surveillance results of iodine deficiency disorders in Guangdong Province in 2011

目的评价广东省碘缺乏病防治效果及碘营养状况。方法于2011年，在广东省按人口比例概率抽样法抽取30个县（市、区），从每个县（市、区）中各抽取1个乡镇（街道），每个乡镇（街道）中抽取1所小学．每个小学抽取8～10岁儿童40名检查甲状腺及采集家中盐样，用于盐碘测定。从40名儿童中，抽取12名儿童，采集尿样，用于尿碘测定。在抽中的小学校，抽取5年级学生40人进行智商（IQ）测验。在小学校附近，选择3个乡（镇、街道），每个乡（镇、街道）抽取孕妇和哺乳妇女各5人，采集尿样用于尿碘测定。甲状腺检查采用B超法；盐碘测定采用直接滴定法；尿碘采用砷铈催化分光光度方法测定；IQ测验采用中国联合型瑞文试验进行。根据地理位置和碘盐落实情况，分析平原及珠三角沿海轻度缺碘地区（碘盐落实地区，简称平原及珠三角）、历史病区（碘盐落实地区）和粤东粤西沿海地区（非碘盐问题地区，简称粤东粤西）的碘缺乏病防治效果。结果检查8～10岁儿童1200名，甲状腺肿大率为3．5％（42／1200），不同地理位置儿童甲状腺肿大率比较差异有统计学意义（X^2=6．6，P〈0．05），其中粤东粤西儿童甲状腺肿大率（6．1％）明显高于平原及珠三角和历史病区（3．3％、2．0％，X^2值分别为5．6、7．1，P均〈0．05）。共采集盐样1200份，盐碘均数为31．0mg／kg，变异系数为23．2％，碘盐覆盖率为97．5％（1170／1200），合格碘盐食用率为96．1％（1153／1200）。1200名8，10岁儿童尿碘中位数为186．5μg／L，不同地理位置儿童尿碘中位数比较差异有统计学意义（X^2=5．9，P〈0．05），其中粤东粤西（162．4μg／L）儿童尿碘中位数明显低于平原及珠三角（207．5μg／L，X^2=8．7，P〈0．01）。孕妇和哺乳期妇女尿碘中位数比较差异有统计学意义（X^2=58．9，P〈0．01），其中粤东粤西孕妇和哺乳期妇女尿碘（109．6μg／L）明显低于历史病区和平原及珠三角（152．9、155．2μg／L，X^2值分别为18.3、20．6，P均〈0．05）。1208名5年级学生IQ平均值为102．8±14．3，其中平原及珠三角（104．3±13．9）和历史病区（102．7±14．3）学生IQ高于粤东粤西（100．3±14．7，t值分别为3．8、2．1，P〈0．01或〈0．05）。结论广东省碘缺乏病防治效果显著，实现了消除碘缺乏病目标。普通人群碘营养处于适宜范围，但孕妇碘营养偏低，特别是受非碘盐冲销的粤东粤西应引起重点关注。

Objective To assess the effectiveness of prevention program on iodine deficiency disorders and iodine nutritional status of residents in Guangdong Province. Methods Probability proportionate to size sampling （PPS） was employed in surveillance of iodine deficiency disorders. Thirty counties （cities, districts） were selected in Guangdong Province. In each county （city, district） one township （street） was selected; in each township （street） one primary school was selected and in each primary school d0 children aged 8 - 10 were chosen to examine their thyroid and to collect salt samples at their home for determination of salt iodine. Out of the 40 children, 12 children were chosen to collect urine samples for determination of urinary iodine. From the primary schools chosen, 40 grade 5 students were selected for intelligence quotient（IQ） test. In the nearby of the primary schools, 3 townships （towns, street） were selected and in each township （town, street） 5 pregnant and 5 lactating women were selected to collect their urine samples for determination of urinary iodine. Type-B ultrasonic was used in measuring the thyroid volume. The iodine content of urine samples was measured by the method of arsenic and cerium catalysis spectrophotometry. The iodine content of salt was determined quantitatively with the titration method. IQ was tested by Chinese combined Raven＇s test. According to geographical location and the implementation of iodized salt, the effects of iodized salt on iodine deficiency disorders were analyzed in the plains and the Pearl River Delta Coastal region with mild iodine deficiency （iodized salt implementation region, referred to as the plains and the PRD）, historical iodine deficiency areas（iodized implementation region） and the eastern and the western coastal areas of Guangdong（areas with non-iodized salt problem, referred to as the eastern and the western Guangdong）. Results A total of 1200 children aged 8 to 10 were examined by type-B ultrasonic test, and goiter rate was 3.5% （42/1200）. The differences of goiter rate between the plains and the PRD, the historical iodine deficiency areas and the eastern and the western Guangdong were statistically significant（x2 = 6.6, P 〈 0.05 ）. The goiter rate （6.1%） in the eastern and the western Guangdong was significantly higher than that of the plains and the PRD and the historical iodine deficiency areas （3.3%, 2.0%, X2 = 5.6, 7.1, all P 〈 0.05）. A total of 1200 salt samples were examined. The median and coefficient of variation of iodine in the salt were 31.0 mg/kg and 23.2%, respectively. Coverage of iodized salt was 97.5%（1170/1200） while 96.1% （1153/1200） of consumed iodized salt was qualified. The median urinary iodine of 1200 children aged 8 - 10 was 186.5 μg/L, and the differences of median urinary iodine between the plains and the PRD, the historical iodine deficiency areas and the eastern and the western Guangdong were statistically significant（x2 = 5.9, P 〈 0.05）. The median urinary iodine of the eastern and the western Guangdong（ 162.4 μg,/L） was significantly lower than that of the plains and the PRD（207.5 μg/L, X2 = 8.7, P 〈 0.01 ）. The difference of median urinary iodine between the plains and the PRD, the historical iodine deficiency areas and the eastern and the western Guangdong was statistically significant （x^2 = 58.9, P 〈 0.01）. The median urinary iodine of the eastern and the western Guangdong（109.6 μg/L） was significantly lower than that of the historical iodine deficiency areas and the plains and the PRD （152.9, 155.2 μg/L, X2 = 18.3, 20.6, all P 〈 0.05 ）. The mean IQ of the 1208 grade 5 students was 102.8 ± 14.3. The IQ of the plains and the PRD（104.3 ± 13.9） and the historical iodine deficiency areas（ 102.7± 14.3） was significantly higher than that of the eastern and the western Guangdong （ 100.3± 14.7, t = 3.8, 2.1, P 〈 0.01 or P 〈 0.05）. Conclusions The goal Of iodine deficiency disorders elimination is achieved as scheduled in Guangdong Province. The health level of general population has been improved significantly. Iodine nutrition is in the appropriate range （100 - 199 μg/L） in general population but low in pregnant women. The selling of non-iodized salt in the eastern and the western Guangdong Province should be followed closely.