Effects of bariatric surgery on sex hormones in male patients with obesity

Abstract

Objective: To analyze and evaluate the differences in sex hormones after laparoscopic Roux-en-Y Gastric Bypass Surgery (LRYGB) and laparoscopic sleeve gastrectomy (LSG) in male patients with obesity. Methods: This study was a retrospective cohort study. The inclusion criteria were (1) male patients with obesity who met the surgical indications of the "Chinese Guidelines for Surgical Treatment of Obesity and Type 2 Diabetes" (2019 Edition); (2) patients with a body mass index (BMI) of ≥27.5 kg/m2 and obesity-related metabolic diseases, or patients with severe obesity and a BMI of ≥35 kg/m2; and (3) sex hormone levels checked 1 year after surgery. The exclusion criteria included (1) patients with endocrine diseases (thyrotoxicosis, hyperprolactinemia) and hypothalamic-pituitary lesions and (2) those with severe major organ dysfunction who could not tolerate anesthesia or surgery. According to the above criteria, the clinical data of male patients with obesity admitted to the Gastrointestinal Surgery/Bariatric Center of the First Affiliated Hospital of Jinan University from October 2017 to January 2020 were included. A total of 52 male patients with obesity were included in this study. The mean age, body weight, BMI, and total testosterone level were (29.3±10.2) years, (123.6±35.4) kg, (40.1±11.1) kg/m2, and 7.6 (5.5, 9.1) nmol/L, respectively. Forty-five patients (86.5%) exhibited testosterone deficiency. Among all the patients, 29 underwent LSG (LSG group) and 23 underwent LRYGB surgery (LRYGB group). The main outcome measure was the change in sex hormone levels before and after bariatric surgery in all the patients. The secondary outcome measures were the comparison of changes in sex hormone levels before and after LSG and LRYGB. Results: Pearson correlation analysis showed that preoperative estradiol was positively correlated with waist circumference (R=0.299, P<0.05), hip circumference (R=0.326, P<0.05), and chest circumference (R=0.388, P<0.05). Testosterone was negatively correlated with BMI (R=-0.563, P<0.01), waist circumference (R=-0.521, P<0.01), hip circumference (R=-0.456, P<0.01), chest circumference (R=-0.600, P<0.01), and neck circumference (R=-0.547, P<0.01). One year following bariatric surgery, the serum testosterone (7.6 [5.5, 9.1] nmol/L vs. 13.6 [10.5, 15.4] nmol/L, Z=-5.910, P<0.001), follicle-stimulating hormone (4.7 [2.7, 5.3] IU/L vs. 6.5 [3.6, 7.8] IU/L, Z=-4.658, P<0.001), and progesterone (1.2 [0.4, 1.5] nmol/L vs. 1.9 [0.8, 1.3] nmol/L, Z=-2.542, P=0.011) levels were significantly higher in all the patients. Both estradiol (172.8 [115.6, 217.5] pmol/L vs. 138.3 [88.4, 168.1] pmol/L, Z=-2.828, P=0.005) and prolactin (11.4 [6.4, 14.6] mIU/L vs. 8.6 [4.8, 7.3] mIU/L, Z=-2.887, P=0.004) levels were decreased. In addition to prolactin levels in the LRYGB group, there were statistically significant differences in the levels of estradiol (P=0.030), follicle-stimulating hormone (P < 0.001), luteinizing hormone (P=0.033), progesterone (P=0.034), and testosterone (P<0.001) compared with their preoperative levels. In the LSG group, there were statistically significant differences in the levels of follicle-stimulating hormone (P=0.011), prolactin (P=0.023), and testosterone (P<0.001) compared with their preoperative levels. Conclusion: The degree of obesity in men was negatively correlated with testosterone levels. Both LRYGB and LSG can significantly improve sex hormone levels in male patients with obesity, and testosterone levels show a significant increase after surgery.