Roles of TgAb and TPOAb in the Development of Hypothyroidism After ~(131)I Treatment in Hyperthyroid Patients With Graves' Disease

To evaluate the roles of antithyroid peroxidase antibodies(TPOAb) and antithyroglobulin antibodies(TgAb) in the development of hypothyroidism after 131I treatment in hyperthyroid patients with Graves' disease(GD),data were collected from 160 GD patients who were treated with 131I in the department of nuclear medicine of Tongji Hospital between January 2008 and February 2011.Patients were divided into four groups: group A(TgAb60.00 U/mL,TPOAb60.00 U/mL),group B(TgAb≥60.00 U/mL,TPOAb60.00 U/mL),group C(TgAb60.00 U/mL,TPOAb≥60.00 U/mL),and group D(TgAb≥60.00 U/mL,TPOAb≥60.00 U/mL).Chi-square criterion and logistic regression analysis were used to evaluate the roles of TPOAb and TgAb in the development of hypothyroidism.The results showed that hypothyroidism was observed in 34.4% of the patients with GD treated with 131I.The incidence of hypothyroidism after 131I treatment was different for each group(P=0.0340.05),with group C and D having significantly higher incidence than group A(P=0.0410.05 and P=0.0050.01,respectively).Logistic regression analysis showed that the TGAb levels(Wald = 4.145,P=0.042 0.05) and the TPOAb levels(Wald = 6.850,P=0.009 0.01) played important roles in the occurrence of hypothyroidism after 131I treatment.In conclusion,because TgAb and TPOAb play important roles in the occurrence of hypothyroidism after 131I therapy,in patients with positive levels of TgAb and TPOAb,lower doses of 131I might prevent hypothyroidism.