Goiter and urinary Iodine excretion survey of 8-10 years old school children in Tehran province, 17 years after universal salt iodisation (2007)

Following two decades of intensive efforts work in IDD elimination, Iran has been recognized as an IDD free country in the Middle-East region. This study was performed to evaluate the adequacy of iodine intake, 17 years after universal salt iodization in Tehran and to compare the results with those of previous studies. In this cross-sectional study, 8 to10 year-old schoolchildren, randomly selected from Tehran province, were evaluated in year 2007, using data gathered on goiter prevalence, urinary iodine excretion, iodine content of household salts and thyroid volume measured by ultrasonography the results obtained were compared with those documented for 1996 and 2001. In this study, 1200 children were evaluated. Total prevalence of goiter was 2.3% no one had grade 2 goiter. The median urinary iodine in 120 schoolchildren was 94.1µg/L. Only 54.9% of Tehranian households were using iodized salt and salt storage was appropriate in 47.9% of households salt used by 62.5% of households had less than 15 µg iodide. Ultrasonic measurement of thyroid volume was performed in 464 schoolchildren, aged 7-15 years, and while the median thyroid volume of girls aged 7-11 years was slightly more than that of boys, the 97th percentile thyroid volume of both sexes was similar for all age groups. Thyroid volumes were significantly correlated with age, weight, height and body surface area. Goiter prevalence has decreased significantly in Tehran, the central province of Iran, 17 years after universal salt iodization. However the median urinary iodine of school children has decreased in comparison to results of studies conducted in 1996 and 2001. Continuous monitoring of national programs is essential for IDD elimination.