[Changes of sex hormones and sex hormone-binding globulin levels in male adults with hyperthyroidism before and after antithyroid drug treatment].

Objective To observe the changes of sex hormone and sex hormone-binding globulin (SHBG) levels in young male patients with hyperthyroidism before and after antithyroid drug (ATD) treatment. Methods Between January 2015 and July 2016, forty male patients with hyperthyroidism aged 19-52 years (with an median age of 33.1 years) were enrolled in the Department of Endocrinology of Peking Union Medical College Hospital. Blood samples were taken before treatment and at 1 month, 2 months, 3 months and 5 months after treatment to evaluate thyroid function, follicle stimulating hormone (FSH), luteinizing hormone (LH), testosterone(T), free testosterone(FT), estradiol(E2), prolactin and SHBG. Results A total of 40 patients were enrolled but only 35 patients completed the follow-up. The patients had high levels of thyroid function, SHBG and sex hormones before treatment. Before treatment, free thyroxine (FT4), free triiodothyronine (FT3), SHBG, LH, estradiol, testosterone and free testosterone was (0.30±0.12) pmol/L, (9.68±4.73) pmol/L, (146±111) nmol/L, (8.41±3.61) U/L, (19.9±7.7) pmol/L, (29.9±9.5) nmol/L and (0.24±0.08) nmol/L, respectively. After treatment, the level of triiodothyronine, thyroxine, FT3 and FT4 gradually decreased to normal (all P 0.05). However FT/LH gradually increased and its difference was statistically significant (P<0.001). Conclusion The levels of LH, estradiol, testosterone and SHBG in male patients with hyperthyroidism significantly increased, while the free testosterone level decreased, but they all gradually returned to normal with the lowering of thyroid hormone levels during ATD treatment. Key words: Hyperthyroidism; Testosterone; Estradiol; Sex hormone-binding globulin