title: Iodine nutrition and thyroid diseases in Chengdu, China: an epidemiological study.
abstract: OBJECTIVE
  To assess the iodine nutritional status and investigate the prevalence of thyroid diseases in a community population in Chengdu, China.
  
  
  METHODS
  Eighty school-age children were randomly selected for measurements of urinary iodine concentration. A total of 1500 residents over the age of 18 who had lived in Chengdu for more than 5 years were selected by stratified cluster sampling. Serum thyroid hormone concentrations and thyroid autoantibodies were measured, and thyroid ultrasonography was performed.
  
  
  RESULTS
  The median urine iodine concentration was 184 µg/l in school-age children. The prevalence of clinical hyperthyroidism, subclinical hyperthyroidism, clinical hypothyroidism and subclinical hypothyroidism was 0.97%, 1.95%, 0.90% and 5.55%, respectively. The prevalence of thyroid autoantibodies and thyroid nodules was 15.82% and 16.87%, respectively. The prevalence of clinical hyper- and hypothyroidism was greater in females than in males (P < 0.05). The prevalence of subclinical hyper- and hypothyroidism, thyroid nodules and thyroid autoantibodies increased significantly with age (P < 0.05). The rate of new abnormal TSH was 9.37%, and the average serum Thyroid Stimulating Hormone (TSH) concentrations increased with age. When TSH >0.71 mU/l, the prevalence of positive TPOAb and/or TgAb increased significantly with rising concentrations of TSH (P < 0.05); however, the prevalence of thyroid nodules did not increase with escalating concentrations of TSH (P = 0.09).
  
  
  CONCLUSIONS
  Subclinical thyroid diseases, especially subclinical hypothyroidism and thyroid nodules, are common in an iodine sufficient area. Females and the elderly might benefit from routine screening for thyroid diseases, followed by appropriate detection and treatment.
authors.affiliation: From the Department of Endocrinology and Metabolism, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China, Department of Geriatrics Medicine of Sichuan Provincial People's Hospital, Chengdu, Sichuan 610041, China and Department of General Medicine, Yulin Community Health Service Center, Wuhou District, Chengdu, Sichuan 610041, China.
authors.forename: Y R
authors.initials: YR
authors.lastname: Yan
authors.affiliation: From the Department of Endocrinology and Metabolism, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China, Department of Geriatrics Medicine of Sichuan Provincial People's Hospital, Chengdu, Sichuan 610041, China and Department of General Medicine, Yulin Community Health Service Center, Wuhou District, Chengdu, Sichuan 610041, China From the Department of Endocrinology and Metabolism, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China, Department of Geriatrics Medicine of Sichuan Provincial People's Hospital, Chengdu, Sichuan 610041, China and Department of General Medicine, Yulin Community Health Service Center, Wuhou District, Chengdu, Sichuan 610041, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Liu
authors.affiliation: From the Department of Endocrinology and Metabolism, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China, Department of Geriatrics Medicine of Sichuan Provincial People's Hospital, Chengdu, Sichuan 610041, China and Department of General Medicine, Yulin Community Health Service Center, Wuhou District, Chengdu, Sichuan 610041, China sansan1880@126.com.
authors.forename: H
authors.initials: H
authors.lastname: Huang
authors.affiliation: From the Department of Endocrinology and Metabolism, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China, Department of Geriatrics Medicine of Sichuan Provincial People's Hospital, Chengdu, Sichuan 610041, China and Department of General Medicine, Yulin Community Health Service Center, Wuhou District, Chengdu, Sichuan 610041, China.
authors.forename: Q G
authors.initials: QG
authors.lastname: Lv
authors.affiliation: From the Department of Endocrinology and Metabolism, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China, Department of Geriatrics Medicine of Sichuan Provincial People's Hospital, Chengdu, Sichuan 610041, China and Department of General Medicine, Yulin Community Health Service Center, Wuhou District, Chengdu, Sichuan 610041, China.
authors.forename: X L
authors.initials: XL
authors.lastname: Gao
authors.affiliation: From the Department of Endocrinology and Metabolism, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China, Department of Geriatrics Medicine of Sichuan Provincial People's Hospital, Chengdu, Sichuan 610041, China and Department of General Medicine, Yulin Community Health Service Center, Wuhou District, Chengdu, Sichuan 610041, China.
authors.forename: J
authors.initials: J
authors.lastname: Jiang
authors.affiliation: From the Department of Endocrinology and Metabolism, West China Hospital, Sichuan University, Chengdu, Sichuan 610041, China, Department of Geriatrics Medicine of Sichuan Provincial People's Hospital, Chengdu, Sichuan 610041, China and Department of General Medicine, Yulin Community Health Service Center, Wuhou District, Chengdu, Sichuan 610041, China.
authors.forename: N W
authors.initials: NW
authors.lastname: Tong
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D001323:Autoantibodies / Q000097:blood*; D002648:Child; D002681:China / Q000453:epidemiology; D016021:Epidemiologic Studies; D005260:Female; D006801:Humans; D007455:Iodine / Q000652:urine*; D008297:Male; D008875:Middle Aged; D009752:Nutritional Status; D017678:Sex Distribution; D013959:Thyroid Diseases / Q000453:epidemiology*; D013961:Thyroid Gland / Q000000981:diagnostic imaging; D013963:Thyroid Hormones / Q000097:blood*; D016606:Thyroid Nodule / Q000453:epidemiology*; D013972:Thyrotropin / Q000097:blood*; D014463:Ultrasonography; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D013963:Thyroid Hormones; D013972:Thyrotropin; D007455:Iodine