Prevalence of hyperthyroidism in Isfahan-Iran, in the ear 2006, fifteen years after universal salt iodization: a community based study

The objective of this study was to investigate the prevalence of hyperthyroidism in Isfahan, a centrally located city in Iran, fifteen years after universal salt iodization. In a cross-sectional study, 2523 Isfahani adult people (aged >20 years, 1275 men and 1248 women) were selected by multistage cluster sampling method. TSH was measured in all (n=2523) and urinary iodine concentration (UIC) in one fourth of participants. Those with low TSH 0.05). Thyroid function had no statistically significant correlation with iodine intake status. Nobody had UIC more than 100 μg/dl. The prevalence of positive TPOAb and/ or TgAb was 54.5% and 29.2% in hyperthyroid and euthyroid people, respectively (OR= 2.9, CI 95%: 1.2-7, P=0.01). Conclusions:The rate of hyperthyroidism in our region was similar to iodine sufficient areas. Its development is not a direct effect of iodine intake. Antithyroid autoimmunity may have a role.