The prevalence of Graves’ disease and related factors recurrence following discontinuation of antithyroid agents

Abstract Background: Although iodine supply has reached to adequate levels in the recent years in Iran, it is evidently lower than the amount in western countries and USA. Some studies indicate that the quantity of iodine supplies present in food substances is effective in the recurrence of Graves’ disease. Objective: To determine the prevalence of Graves’ recurrence and related factors following dicontinuation of antithyroid agents. Methods: In a cross-sectional study based on easy sampling, 204 euthyroid out patients with Graves’ disease, treated with methimazole for 12-59 months, were selected and evaluated for the reccurence of disease a year later following the continuation of therapy. Parameters likes age, goiter size at the beginning and end of the treatment, severity of disease (T4 value), drug maintenance dose and the duration of treatment were studied. T test and X2 were used to analysis the data statistically. Findings: The one-year prevalence of disease recurrence following the medicine withdrawal was 44.6%, with a duration of 1-12 months (mean=7). There was no significant relation between the recurrence of disease and the age, sex, maintenance dose, goiter size before and after the treatment and also the T4 value at the beginning and the duration of treatment. Conclusion: The one-year prevalence of Graves’ disease recurrence following antithyroids withdrawal was significantly lower than the values in countries with rich iodine supplies. This finding is in accord with studies indicating that the level of iodine intake is effective in the recurrence of Graves’ disease.