Abstract:

Objective To retrospectively analyze correlative factors and therapeutic effect for the treatment to Graves disease by ¹³¹I and to identify critical influencing factors of one treatment and multi-treatments. Methods A total of 455 outpatients with Graves disease underwent the ¹³¹I treatment. The dose of ¹³¹I was determined based on the dose formula and clinical experience. For unrecovered or recurrent patients, the same treatment was repeated after 3 months or more until they were cured. Patients were followed up for more than 1 year after the treatment. The differences of correlative factors and therapeutic effect of patients cured by 1 treatment or multi-treatments were retrospectively analyzed and critical influencing factors and their clinical values were identified. Results There were 367 patients (80.7%) and 88 patients(19.3%) who were cured by one treatment (one treatment group) and multi-treatments (multi-treatment group), respectively. The differences of age, gender, 24h ¹³¹I uptake rate, withdrawal time of antithyroid drugs (ATD), thyroid hormone and autoantibody levels before treatment, and thyroid weight of two groups were not statistically significant (P>0.05). The activity values of the first 131I treatment of one treatment group and multi-treatment group were (314.5±136.9) MBq and (292.3±96.2) MBq, respectively (t=2.590 7, P<0.01). The ratios of ¹³¹I dose of the first treatment and thyroid weight of two groups were (3.8±1.2) MBq/g and (3.5±1.0) MBq/g (t=2.105 4, P<0.05). The total activity values of two groups were (314.5±136.9) MBq and (706.7±399.6) MBq (t=-13.283 0, P<0.01). There were 186 patients (50.7%) of one treatment group and 48 patients (54.5%) of multi-treatment group suffered from the permanent hypothyroidism (χ²=0.283 7, P>0.05). Conclusion For the Graves disease, one ¹³¹I treatment is better than multi ¹³¹I treatments. The critical influencing factor is that the activity of the first ¹³¹I treatment should be sufficient. Average MBq/g ratio ≥4.4 is recommended.

Key words: ¹³¹I, Graves disease, curative effect, retrospective analysis