Background: Male obesity can be associated with symptomatic alterations in sex hormones resulting in hypogonadism and impaired fertility. Surgical-induced weight loss can improve the sex hormone profile in men. The aim of the present study is to evaluate the levels of sex hormones in obese males before and after 6 months from bariatric surgery. Possible mechanisms and clinical implications are also discussed.
Methods: We evaluated levels of serum total testosterone (TT), sex hormone-binding globulin (SHBG), calculated free testosterone (cFT), follicular-stimulating hormone (FSH), luteinizing hormone (LH), and total estradiol (E2) in 20 male patients at the baseline and 6 months after bariatric surgery.
Results: Median [interquartile range] age at the time of surgery was 40.5 [27.2-46.7] years with a median [interquartile range] BMI of 43.6 [40.9-48.7] kg/m(2). The median baseline levels of TT, SHBG, cFT, LH, and FSH were reduced; levels of E2 were elevated. At 6 months from surgery, the median BMI dropped to 34.8 [31.7-40.5] kg/m(2), TT, SHBG, cFT, LH, and FSH increased, while levels of E2 decreased. The improvement in the sex hormone profile was more evident in younger patients, with a statistically significant difference in cFT following surgery and in the raise of TT and cFT between the groups of patients below and above 35 years. At multivariate analysis, the age was the best predictive factor of the postoperative variations of TT.
Conclusions: These preliminary results confirm the general improvement in sex hormone profile in obese men after bariatric surgery and introduce the age as a possible contributing factor to this improvement.