Endocrine Abstracts

Introduction: In Graves’ hyperthyroidism with long-term antithyroid drugs (ATD) treatment, remission is often umpredictable. However variables at diagnosis or at the end of the ATD regimen are associated with a highest likelihood of recurrence and could be used to decide an ablative treatment.

Objective: To identify variables before and at the end of a long-term treatment with ATD (>6 months) associated with higher rates of relapse during a follow-up of at less 1 year after discontinuing ATD.

Subjects: About 250 subjects with a first episode of Graves’ disease between January 1999 and December 2004 seen in the same institution.

Results: At baseline mean age was 41±14 years, 21% were male and 33% smokers, 49% used iodinated salt and 40% were classified as having a goiter > grade 2. Mean TSI decreased from 11±18 to 2.5±4 (P<0.05) at the end of ATD regimen. About 29% were excluded of a further analysis because of an ablative treatment as soon as ATD were stopped. Relapse ocurred in 60% of the resting 177 subjects submitted to a long-term treatment (mean 18±8 months) during the follow-up period (mean: 3.1±1.7 years). Of analyzed variables at diagnosis,only male gender, smoking history and iodinated salt use were significantly associated with failure of medical treatment. In a logistic regression analysis only male gender and smoking cigarettes were independent predictive factors for recurrence. TSI 3 times above the normal value at the end of the treatment yield a 98% positive predictive value for relapse.

Conclusion: Recognition of variables at diagnosis of Graves’ disease or at the end of long-term ATD course could be used to select pacients for surgery or radioiodine because of lower remission rate with medical treatment.