Marwaha R K, Tandon Nikhil, Gupta Nandita, Karak A K, Verma K, Kochupillai N
Department of Endocrinology, All India Institute of Medical Sciences, New Delhi, India.
Clin Endocrinol (Oxf). 2003 Dec;59(6):672-81. doi: 10.1046/j.1365-2265.2003.01895.x.
This study was done to assess goitre prevalence, thyroid functional status and cause of residual goitre among school children in the postsalt iodization phase in India.
A cross-sectional study in which, 14762 school children in the age group of 6-18 years, from different States and Union territories of India, were evaluated for goitre prevalence, urinary iodine and thiocyanate excretion, functional status of the thyroid as well as serological and cytopathological markers for thyroid autoimmunity.
Urinary iodine (wet ashing method), urinary thiocyanate (colourimetric method), serum thyroxine [in-house radioimmunoassay (RIA)], serum TSH (IRMA), antithyroid microsomal and antithyroglobulin antibodies (haemagglutination method) were estimated. Fine-needle aspiration cytology was performed in all goitrous subjects giving consent.
The overall goitre prevalence was 23% (27.1% girls; 17.8% boys, P < 0.001). Subjects belonging to poor socio-economic strata had significantly higher goitre prevalence. Median urinary iodine excretion (UIE) in goitrous subjects (2-53 micromol/l) was significantly higher than in controls (2-24 micromol/l; P < 0.001). Levels of UIE observed among goitrous subjects showed no relationship with the presence or absence of thyroid dysfunction or with thyroid antibody status. High titres (> or = 1:1600) of TMA were present more often in goitrous subjects (6.08%) than nongoitrous controls (0.34%; P < 0.001) and in girls (7.3%) than boys (2.35%; P < 0.001). TMA positivity were significantly more among goitrous subjects with thyroid dysfunction than in euthyroid subjects. Significantly higher median urinary thiocyanate (USCN) excretion was observed in goitrous subjects (0.75 mg/dl) compared to controls (0.64 mg/dl; P < 0.001) and goitrous girls compared to goitrous boys. USCN excretion of goitrous subjects and controls showed no relationship with functional or thyroid antibody status in various groups.
Persistent, albeit reduced prevalence of goitre, despite adequate iodine prophylaxis, suggests existence of additional factors in goitrogenesis in India. Thyroid autoimmunity can explain only a part of the goitre prevalence. The role of goitrogens in residual goitre prevalence is brought forth.
本研究旨在评估印度食盐加碘阶段学龄儿童的甲状腺肿患病率、甲状腺功能状态以及残余甲状腺肿的病因。
一项横断面研究，对来自印度不同邦和中央直辖区的14762名6至18岁学龄儿童进行甲状腺肿患病率、尿碘和硫氰酸盐排泄、甲状腺功能状态以及甲状腺自身免疫的血清学和细胞病理学标志物评估。
采用湿灰化法测定尿碘，比色法测定尿硫氰酸盐，采用内部放射免疫分析法（RIA）测定血清甲状腺素，免疫放射分析法（IRMA）测定血清促甲状腺激素，血凝法测定抗甲状腺微粒体抗体和抗甲状腺球蛋白抗体。对所有同意的甲状腺肿患者进行细针穿刺细胞学检查。
总体甲状腺肿患病率为23%（女孩为27.1%；男孩为17.8%，P<0.001）。社会经济阶层较低的受试者甲状腺肿患病率显著更高。甲状腺肿患者的尿碘排泄中位数（UIE）（2 - 53微摩尔/升）显著高于对照组（2 - 24微摩尔/升；P<0.001）。甲状腺肿患者中观察到的UIE水平与甲状腺功能障碍的有无或甲状腺抗体状态无关。甲状腺肿患者中高滴度（≥1:1600）的甲状腺微粒体抗体（TMA）出现频率（6.08%）高于非甲状腺肿对照组（0.34%；P<0.001），女孩（7.3%）高于男孩（2.35%；P<0.001）。甲状腺功能障碍的甲状腺肿患者中TMA阳性率显著高于甲状腺功能正常的患者。与对照组（0.64毫克/分升；P<0.001）相比，甲状腺肿患者的尿硫氰酸盐（USCN）排泄中位数显著更高（0.75毫克/分升），甲状腺肿女孩高于甲状腺肿男孩。甲状腺肿患者和对照组的USCN排泄与各亚组的功能或甲状腺抗体状态无关。
尽管碘预防措施充分，但甲状腺肿患病率仍持续存在且有所降低，这表明印度甲状腺肿发生存在其他因素。甲状腺自身免疫仅能解释部分甲状腺肿患病率。甲状腺肿原在残余甲状腺肿患病率中的作用被揭示。
