Goiter Prevalence, Urinary Iodine and Thyroid Function Tests in Inhibitants of Tehran City

Introduction: As the production, distribution and consumption of iodised salt has increased in recent years, this study was carried out to monitor the IDD control program in Tehran, in 1996.   Methods:1146 families comprising 5140 subjects intwenty districts of Tehran City from all age groups were randomly selected. Thyroid size was examined by palpation and graded according to WHO classification. In 163 families selected randomly and comprising of 749 subjects, (digestion method) and TH, T, and TSH (RIA) were measured. Results: In 3111 females and 2029 males percentage of grades 1 & 2 goiter were 44 & 44 in females and 49 & 33% in males, respectively. Mean urinary iodine was 17.5±5.3 µg/dl. Urinary iodine was below 2 in 1.2% of subjects, 2-5 in 2.8%, 5-10 in 9.1%, 10-25 in 78.5%, >25 µg/dl in 8.4%. Serum T4, T3 and TSH concentrations were 8.4±1.4 µg/dl, 170±37 µg/dl and 1.4±0.08 µU/ml, respectively. Prevalence of thyrotoxicosis was not increased Conclusion: This study demonstrates that iodine intake in the majority of families residing in Tehran city is adequate. High goiter prevalence observed in this study points to the fact that the length of iodised salt consumption has not been long enough to affect the prevalence rate.