Iodine nutrition and thyroid diseases in Chengdu, China: an epidemiological study

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 concen-tration. 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 autoan-tibodies were measured, and thyroid ultrasonog-raphy was performed. Results: The median urine iodine concentration was 184 mg/l in school-age children. The prevalence of clinical hyperthyroidism, subclinical hyperthyroid-ism, clinical hypothyroidism and subclinica