Abstract:
Objective To explore the effect of additional selenium on the serum levels of thyroid peroxidase antibody(TPOAb) after treatment of Graves disease with 131I.
Methods A total of 266 patients with TPOAb levels between 10 and 1300 IU/ml participated in this study. TPOAb levels within 10 IU/ml to 60 IU/ml were considered negative, and levels greater than 60 IU/ml were considered positive. All patients were randomly divided into control(n=112) and selenium treatment group(n=154). After treatment with 131I, the control group received conventional therapy, whereas the selenium treatment group received additional selenium(100 μg twice a day). The TPOAb levels and positive ratios of the two groups were compared with pre-therapy levels after treatment for 6 and 12 months.
Results After 6 months, the TPOAb levels in both groups significantly increased compared with the pre-therapy levels(control group:Z=-2.084, P < 0.05; selenium treatment group:Z=-2.112, P < 0.05). However, no significant difference existed in the TPOAb levels between the two groups(Z=-0.764, P > 0.05). After 12 months, the TPOAb levels in the control group did not change significantly compared with the pre-therapy levels(Z=-1.538, P > 0.05), whereas the TPOAb levels in the selenium treatment group significantly decreased compared with the pre-therapy levels(Z=-5.465, P < 0.01). The difference between the two groups were statistically significant(Z=-2.180, P < 0.05). The positive ratios of TPOAb for both groups did not change significantly 6 or 12 months after 131I therapy(control group:x12= 0.720, x22=0.103, both P > 0.05; selenium treatment group:x12=0.023, x22=0.340, both P > 0.05). Overall, the positive ratios were not statistically significant between the two groups(x12=0.001, x22=0.366, both P > 0.05).
Conclusion Additional treatment with selenium after 131I therapy for Graves disease can effectively decrease the TPOAb levels, especially for patients with high initial TPOAb levels.