Yung Lee, BHSc1, Jerry Dang, MD2, James Yu, BHSc1, Chunhong Tian, PhD2, Noah Switzer, MD, MPH2, Daniel W Birch, MD, MSc2, Shahzeer Karmali, MD, MPH2. 1McMaster University, 2University of Alberta
Background: This systematic review and meta-analysis aims to establish the effects of bariatric surgery on male sex hormones, sperm parameters, and sexual function. Men with obesity experience lower testosterone levels, lower sexual satisfaction, and reduced fertility. The literature on the effect of bariatric surgery on male sex hormones and sperm quality is considerable and has not been comprehensively reviewed and meta-analyzed.
Methods: We searched the following databases covering the period from database inception through June 2018: MEDLINE, EMBASE, Web of Science, and Scopus. Articles were eligible for inclusion if the studies examined the effect of bariatric surgery on male sex hormones and sperm parameters in patients with obesity. Primary outcomes of interest were: (1) sex hormones (luteinizing hormone (LH), follicle stimulating hormone (FSH), total estradiol, free estradiol, total testosterone, free testosterone, dehydroepiandrosterone (DHEA), androstenedione, sex hormone binding globulin (SHBG), prolactin, inhibin B) and (2) sperm quality (sperm volume, sperm concentration, % total motility, % normal morphology, % progressive motility. Secondary outcome was sexual function (International Index of Erectile Function (IIEF) score). Pooled estimates were calculated using random effects meta-analyses and heterogeneity was quantified using the inconsistency (I2) statistic.
Results: A total of 28 cohort studies with 1,022 patients were identified from 3,896 potentially relevant citations. Both free and calculated testosterone levels were significantly increased after bariatric surgery (Mean Difference (MD) -7.47 nM, 95% CI -8.62 to -6.31, p<0.001 and MD -0.05 nM, 95% CI -0.07 to -0.02, p<0.001 respectively). Consistent with the increase in testosterone levels, LH, FSH, and SHBG levels were also significantly increased after surgery. In contrast, free and total estradiol and prolactin levels were significantly decreased after bariatric surgery. From only five studies that reported the IIEF score, bariatric surgery led to a small, but statistically significant increase in erectile function after surgery (MD -0.46, 95% CI -0.89 to -0.02, p=0.04). However, bariatric surgery did not affect any of the sperm parameters, DHEA, androstenedione, and inhibin B levels. Most of the sex hormone meta-analyses results had considerable heterogeneity (I2 >50%).
Conclusions: Sustained weight-loss induced by bariatric surgery had an effect on male sex hormones and decreased female sex hormones in male patients with obesity. However, sperm quality and function were not improved after surgery. Long-term comparative studies or adequately powered randomized controlled trials are warranted to examine the impact of bariatric surgery on male sex hormones and sperm quality.
Presented at the SAGES 2017 Annual Meeting in Houston, TX.
Abstract ID: 91970
Program Number: P132
Presentation Session: Poster Session (Non CME)
Presentation Type: Poster