不同碘营养水平对育龄妇女甲状腺功能的影响

Thyroid function of women of reproductive age in iodine sufficiency and iodine deficiency

目的研究不同碘营养水平对育龄妇女甲状腺功能的影响。方法选择新疆巩留县和伊宁县各50名育龄妇女（非孕）作为碘充足组和碘缺乏组，按统一设计的调查项目表，逐项询问、检查、填写；内容包括家庭食用盐和饮用水的种类，个人甲状腺疾病史和甲状腺肿大情况。采集调查对象饮用水、食盐、尿液，分别用直接滴定法、砷铈催化分光光度法检测含碘量；采集并用化学发光免疫法检测静脉血清中的TSH、FT4、FT3水平。结果碘缺乏组和碘充足组碘盐覆盖率分别为72％和100％，前者低于后者（X2=16．28，P〈0．01）；尿碘中位数分别为95．5μg／L[四分位间距（QR）=50．0μg／L]和167．4μg／L（QR=186．4μg/L），前者低于后者（U=632．00，P〈0．01）；血清TSH中位数分别为2．56、1．88mU／L，前者有高于后者的趋势，但差异无统计学意义（U=990．50，P〉0．05）；血清FT4分别为（14．7±2．0）、（17．0±3．8）pmol／L，前者明显低于后者（t=3．76，P〈0．01）；血清FT3分别为（5．1±1．4）、（4．8±0．5）pmol／L，二者比较差异无统计学意义（t=1．59，P〉0．05）；FT3/FT4比值分别为0．33±0．04、0．30±0．04，二者比较差异有统计学意义（t=3．13，P〈0．01）；甲状腺功能异常检出率分别为20．0％（10／50）、8．0％（4／50），二者比较差异无统计学意义（X2=2．99，P〉0．05）。结论育龄妇女的碘营养缺乏是导致自身甲状腺功能低下的主要原因，坚持长期食用碘盐是彻底纠正机体缺碘状况的最有效方法。

Objective To study the effects of different level of iodine nutrition on the thyroid function in women of reproductive age. Methods A total of 100（50 from each） women of reproductive age but not pregnant were collected from iodine deficient and adequate areas. The questionnaire was obtained individually with items concerning personal history of thyroid diseases, goiters and category of edible salt and drinking water based on the project design. The household salt and drinking water were collected for measuring iodine content, and blood samples were obtained for TSH, FT4 and FT3 testing. Results The coverage of iodized salt and the median level of urinary iodine in iodine deficient women（72.0% and 95.5 μg/L） were obviously lower than that in iodine sufficient women（ 100.0% and 167.4 μg/L, X2 = 16.28, U= 632.00, P 〈 0.01 ）. Median level of serum TSH in iodine deficient women（2.56 mU/L） appeared in an increasing tendency compared to the iodine sufficient women（1.88 mU/L）, but there was no significance （U = 990.50, P 〉 0.05 ）. Serum FT4 mean level in iodine deficient women [ （14.7± 2.0） pmol/L] was lower than that in iodine sufficient women [ （17.0 ± 3.8）pmoI/L, t = 3.76, P 〈 0.011. There was no difference in serum FT3 between two group women[（5.1 ± 1.4）, （4.8 ± 0.5）pmoI/L, t = 1.59, P 〉 0.05]; but FT3/FT4 ratio in iodine deficient women（0.33 ± 0.04） was markedly higher than that in the iodine sufficient women（0.30 ＋ 0.04, t = 3.13, P 〈 0.01 ）. The percentage of thyroid dysfunction in iodine deficient women[20.0% （10/50） ] was higher compared with the iodine sufficient women [ 8.0% （4/50） ], but without significance （X2 = 2.99, P 〉 0.05）. Conclusions Iodine deficiency is a primary cause leading to hypothyroid in women of reproductive age. Long term of iodized salt usage is an efficient way to correct iodine deficiency.