Incidence of thyroid diseases in Zhejiang Province, China, after 15 years of salt iodization.
Thyroid diseases(TD) can be induced by either deficient or excessive iodine intake. Universal Salt Iodization(USI) program has been implemented in China since 1995, to prevent iodine deficiency disorders (IDD). To evaluate the current conditions of TD and the role of USI, a multi-stage stratified random sampling scheme was used to perform a cross-sectional survey on the incidence of TD among participants in 6600 households in Zhejiang Province, a coastal area in China. Iodine nutrition status of the population was assessed by dietary iodine intake recall and urinary iodine concentration (UIC) of the participants, and TD were diagnosed by thyroid ultrasonography for 15122 participants and for 5873 participants by serum criteria for thyroid function(fT3, fT4, TSH, TRAb, TgAb, TPOAb; see Introduction for abbreviations). The median UIC of the surveyed population was 163μg iodine/L. From the participants 23.2% had UIC<100μg/L which is moderately iodine-deficient according to WHO classification. Diffuse goiter was present in 2.3% of the population and thyroid nodule in 20.9%. The incidence of hyperthyroidism, subclinical hyperthyroidism, hypothyroidism, subclinical hypothyroidism, Graves' disease and chronic lymphocytic thyroiditis was 0.5%, 0.6%, 0.6%, 7.8%, 0.2% and 0.3%, respectively. The proportion of several TD for participants with non-iodized salt intake was higher than that for participants with iodized salt intake.
Zhejiang Provincial Center for Disease Control and Prevention, No. 3399 Binshen Road, Hangzhou 310051, China.
Fang
F
Gu
Zhejiang Provincial Center for Disease Control and Prevention, No. 3399 Binshen Road, Hangzhou 310051, China. Electronic address: zgzjcdc@sina.com.
Gangqiang
G
Ding
Zhejiang Provincial Center for Disease Control and Prevention, No. 3399 Binshen Road, Hangzhou 310051, China. Electronic address: zgzjscdc@sina.com.
Xiaoming
X
Lou
Zhejiang Provincial Center for Disease Control and Prevention, No. 3399 Binshen Road, Hangzhou 310051, China. Electronic address: woyanlidiyi@sina.com.
Xiaofeng
X
Wang
Zhejiang Provincial Center for Disease Control and Prevention, No. 3399 Binshen Road, Hangzhou 310051, China. Electronic address: duokanduoji@sina.com.
Zhe
Z
Mo
Zhejiang Provincial Center for Disease Control and Prevention, No. 3399 Binshen Road, Hangzhou 310051, China. Electronic address: 906561622@qq.com.
Wenming
W
Zhu
Zhejiang Provincial Center for Disease Control and Prevention, No. 3399 Binshen Road, Hangzhou 310051, China. Electronic address: 150081832@qq.com.
Jinshui
J
Zhou
Zhejiang Provincial Center for Disease Control and Prevention, No. 3399 Binshen Road, Hangzhou 310051, China. Electronic address: mgm888@sina.com.
Guangming
G
Mao
D000293:Adolescent; D000328:Adult; D002648:Child; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007455:Iodine / Q000008:administration & dosage* / Q000172:deficiency / Q000652:urine; D008297:Male; D017673:Sodium Chloride, Dietary / Q000008:administration & dosage* / Q000652:urine; D013959:Thyroid Diseases / Q000175:diagnosis / Q000453:epidemiology* / Q000378:metabolism / Q000652:urine; D055815:Young Adult
D017673:Sodium Chloride, Dietary; C034024:iodized salt; D007455:Iodine
Diffuse goiter; Iodine intake; Subclinical hypothyroidism; Thyroid nodule; Universal salt iodization (USI); Urinary iodine concentration (UIC)