An analysis of the dose and the therapeutic effect of 131I in treating youngsters with Graves disease

Objective: To analyses the clinical data of 131I in treating youngsters with Graves disease, and to explore the effective dose range which is appropriate for Chinese youngsters with Graves disease. Methods: Two hundred and thirty-four youngsters with Graves disease were selected in this study, their ages were between 8 and 17, the average quality of their thyroids was (59.0±16.5)g. According to the absorbed dose of 131I per gram of thyroid gland, 234 patients were divided into five groups: A: 1.11-<1.48 MBq/g, B: 1.48-<1.85 MBq/g, C: 1.85-<2.22 MBq/g, D: 2.22-2.59 MBq/g, E: >2.59 MBq/g. The therapeutic effect was evaluated by observing after treatment. And calculate the recovery rate, the improvement rate and the incidence rate of hypothyroidism. Results: (1) One hundred and fifty-two (64.95%) patients were cured, 56 (23.93%) were much better than before and 26 (11.11%) were hypothyroid. The therapeutic effect of group B was the best in all groups. (2) The recovery rate: there was no significant difference between group B, group C and group D (χ2=2.68, P>0.05). The recovery rate of group B was better than group A and group E (χ2=10.20 and χ2=5.49, P<0.05). The recovery rate of group A was the lowest. (3) The improvement rate: There was no significant difference between group B, group C, group D and group E (χ2=1.94, P>0.05). The improvement rate of group A was the highest (χ2=8.74, χ2=6.68, χ2=7.01 and χ2=11.12, P<0.05). (4) The incidence rate of hypothyroidism: There was no significant difference between group A, group B, group C and group D (χ2=2.71, P>0.05). Group E had the highest incidence rate of hypothyroidism (χ2=12.36, χ=11.58, χ2=9.37 and χ2=4.36, P<0.05). Conclusion: Using 131I is a safe and effective therapeutic approach for youngsters with Graves disease. We suggest the absorbed dose range of 131I per gram of thyroid gland is 1.48-2.59 MBq/g, which can obtain the better therapeutic effect and can't increase the incidence rate of hypothyroidism. (authors)