Study On The Correlation Between Thyroid 24h RAIU And The Clinical Efficacy Of 131I Therapy For Graves

Objective:In order to evaluate the correlation between 24 hours rate of iodine uptake(24h RAIU) and the clinical efficacy of 131 I therapy for Graves hyperthyroidism.Methods:The data of 3218 patients with Graves hyperthyroidism from August 2009 to July 2014 were collected after a follow-up study, and the follow-up times are from 6 to60 months with the mean as 28.36 +/- 14.06 months. All the patients were the first time treated with radioactive 131 I therapy in our hospital. 2690 patients(83.6% of 3218patients) were follow-up. There were 855 males and 1835 females, and the ages are from11 to 81 years with an average of 42.81 +/- 15.06 years old. Patients with definite 131 I therapy doses were 74 ~ 3700MBq(the mean doses as 409.63+ /- 318.83MBq).According to the thyroid 24 h RAIU before 131 I therapy, the patients were divided into three groups: A group, 405 cases(24 h RAIU < 50.0%); B group, 1764 cases(50.0%≤24h RAIU≤80.0%); C group, 521 cases(24 h RAIU > 80.0%). According to the follow-up results of patients with the 131 I therapy, the patients were divided into two groups: the cured group(including healing and hypothyroidism), and the uncured group(including improving, invalid and recurrence).Results:All of 2690 Graves hyperthyroidisms were treated with radioactive 131 I, 2244 cases were cured(83.4%) and 446 cases were uncured(16.6%). For the 405 patients of A group, 360 cases(88.9%) were cured, 45 cases(11.1%) were uncured; For the 1764 cases of B group, 1534 cases(87.0%) were cured, 230 cases(13.0%) were uncured; For 521 patients of C group, 350 cases(67.2%) were cured, 171 cases(32.8%) were uncured.Between the cure rate and the uncured rate for those Graves hyperthyroidisms in A B C groups statistically significant difference(x2=21.80,P<0.05). The result of Multivariate linear regression analysis indicated that age(b =-0.259), thyroid weight(b = 0.340),gender(b = 0.275), and whether to use ATD treatment(b =-0.226) have linear regression correlation with thyroid 24 h RAIU.Conclusions:Thyroid 24 h RAIU is related to the clinical efficacy of 131 I therapy for Graves hyperthyroidism. The lower the 24 h RAIU implies the higher the cure rate, but the higher the 24 h RAIU means the higher the failure rate. The higher the thyroid weight, the smaller the age, female and no history of ATD treatment are the main reasons for the higher 24 h RAIU. And the smaller the thyroid weight, the bigger the age, male, with history of ATD treatment would lead to the lower 24 h RAIU. This study will provide additional information for clinical 131 I treatment of Graves hyperthyroidism.