title: Hypogonadotropic hypogonadism in morbidly obese males is reversed after bariatric surgery.
abstract: BACKGROUND
  The effect of weight loss by bariatric surgery on gonadal hormones in morbidly obese males is not entirely known. The main objective of the study was to analyze gonadal hormonal changes after weight loss.
  
  
  METHODS
  An observational study was conducted before and after 12 months of weight loss at a clinical research center. Thirty-three men [age 40.5 ± 9.9, body mass index (BMI) 50.3 ± 6.1 kg/m(2)] undergoing bariatric surgery were included. The main outcome measures were as follows: changes in total (TT) and free testosterone (FT), estradiol (E2), sex hormone binding globulin (SHBG), luteinizing hormone (LH), follicle-stimulating hormone (FSH), anti-Müllerian hormone (AMH), inhibin B, and prolactin (PRL).
  
  
  RESULTS
  Baseline prevalence of hypogonadism (defined by TT < 300 ng/dl or FT < 65 pg/ml) was 78.8 and 51.5%, respectively. Hypogonadal patients were older and showed inhibin B and AMH significantly lower than those with normal TT. BMI correlated negatively with TT, LH, and SHBG. Regression analyses showed a significant and independent association of hypogonadism with age (OR = 1.2, p = 0.01), BMI (OR = 1.3, p = 0.03), and AMH (OR = 0.4, p = 0.03) after adjustments. After 1 year, percentage of weight loss (%WL) was 18.8 ± 5.2%, and there was a significant increase of TT, FT, SHBG, and FSH and a decrease of E2 and PRL. Prevalence of persistent hypogonadism after surgery was 6% (low TT) and 15% (low FT). %WL was significantly associated with percent changes in SHBG (r = -0.4, p = 0.04), inhibin B (r = -0.4, p = 0.03), and AMH (r = -0.4, p = 0.01). Age and %WL were the only significant and independent parameters associated with %TT change.
  
  
  CONCLUSIONS
  Obesity-associated hypogonadism is very prevalent in males with morbid obesity and is mostly reversed after sustained weight loss by bariatric surgery.
authors.affiliation: Endocrinology and Nutrition Service, Department of Internal Medicine, Universitat Autònoma de Barcelona, Germans Trias i Pujol University Hospital, Via Canyet, 08916, Badalona, Barcelona, Spain. spellitero.germanstrias@gencat.cat
authors.forename: Silvia
authors.initials: S
authors.lastname: Pellitero
authors.forename: Izaskun
authors.initials: I
authors.lastname: Olaizola
authors.forename: Antoni
authors.initials: A
authors.lastname: Alastrue
authors.forename: Eva
authors.initials: E
authors.lastname: Martínez
authors.forename: María Luisa
authors.initials: ML
authors.lastname: Granada
authors.forename: Jose María
authors.initials: JM
authors.lastname: Balibrea
authors.forename: Pau
authors.initials: P
authors.lastname: Moreno
authors.forename: Assumpta
authors.initials: A
authors.lastname: Serra
authors.forename: Maruja
authors.initials: M
authors.lastname: Navarro-Díaz
authors.forename: Ramon
authors.initials: R
authors.lastname: Romero
authors.forename: Manel
authors.initials: M
authors.lastname: Puig-Domingo
mesh_terms: D000328:Adult; D054304:Anti-Mullerian Hormone / Q000097:blood; D050110:Bariatric Surgery; D015415:Biomarkers / Q000097:blood; D015992:Body Mass Index; D004958:Estradiol / Q000097:blood; D005640:Follicle Stimulating Hormone / Q000097:blood; D006801:Humans; D007006:Hypogonadism / Q000097:blood*; D007265:Inhibins / Q000097:blood; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D009767:Obesity, Morbid / Q000097:blood* / Q000150:complications / Q000601:surgery*; D011388:Prolactin / Q000097:blood; D012016:Reference Values; D012074:Remission Induction; D012738:Sex Hormone-Binding Globulin / Q000378:metabolism; D013739:Testosterone / Q000097:blood; D016896:Treatment Outcome; D015431:Weight Loss
chemical_list: D015415:Biomarkers; D012738:Sex Hormone-Binding Globulin; C422364:inhibin B; D013739:Testosterone; D004958:Estradiol; D007265:Inhibins; D054304:Anti-Mullerian Hormone; D011388:Prolactin; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone