title: Association of hypogonadism with vitamin D status: the European Male Ageing Study.
abstract: OBJECTIVE
  Interrelationships between hormones of the hypothalamic-pituitary-testicular (HPT) axis, hypogonadism, vitamin D and seasonality remain poorly defined. We investigated whether HPT axis hormones and hypogonadism are associated with serum levels of 25-hydroxyvitamin D (25(OH)D) in men.
  
  
  METHODS
  Cross-sectional survey of 3369 community-dwelling men aged 40-79 years in eight European centres. Testosterone (T), oestradiol (E(2)) and dihydrotestosterone were measured by gas chromatography-mass spectrometry; LH, FSH, sex hormone binding globulin (SHBG), 25(OH)D and parathyroid hormone by immunoassay. Free T was calculated from total T, SHBG and albumin. Gonadal status was categorised as eugonadal (normal T/LH), secondary (low T, low/normal LH), primary (low T, elevated LH) and compensated (normal T, elevated LH) hypogonadism. Associations of HPT axis hormones with 25(OH)D were examined using linear regression and hypogonadism with vitamin D using multinomial logistic regression.
  
  
  RESULTS
  In univariate analyses, free T levels were lower (P=0.02) and E(2) and LH levels were higher (P<0.05) in men with vitamin D deficiency (25(OH)D <50 nmol/l). 25(OH)D was positively associated with total and free T and negatively with E(2) and LH in age- and centre-adjusted linear regressions. After adjusting for health and lifestyle factors, no significant associations were observed between 25(OH)D and individual hormones of the HPT axis. However, vitamin D deficiency was significantly associated with compensated (relative risk ratio (RRR)=1.52, P=0.03) and secondary hypogonadism (RRR=1.16, P=0.05). Seasonal variation was only observed for 25(OH)D (P<0.001).
  
  
  CONCLUSIONS
  Secondary and compensated hypogonadism were associated with vitamin D deficiency and the clinical significance of this relationship warrants further investigation.
authors: Arthritis Research UK Epidemiology Unit, Manchester Academic Health Science Centre, The University of Manchester, Manchester M13 9PT, UK.
authors: David M
authors: DM
authors: Lee
authors: Abdelouahid
authors: A
authors: Tajar
authors: Stephen R
authors: SR
authors: Pye
authors: Steven
authors: S
authors: Boonen
authors: Dirk
authors: D
authors: Vanderschueren
authors: Roger
authors: R
authors: Bouillon
authors: Terence W
authors: TW
authors: O'Neill
authors: Gyorgy
authors: G
authors: Bartfai
authors: Felipe F
authors: FF
authors: Casanueva
authors: Joseph D
authors: JD
authors: Finn
authors: Gianni
authors: G
authors: Forti
authors: Aleksander
authors: A
authors: Giwercman
authors: Thang S
authors: TS
authors: Han
authors: Ilpo T
authors: IT
authors: Huhtaniemi
authors: Krzysztof
authors: K
authors: Kula
authors: Michael E J
authors: ME
authors: Lean
authors: Neil
authors: N
authors: Pendleton
authors: Margus
authors: M
authors: Punab
authors: Frederick C W
authors: FC
authors: Wu
mesh_terms: D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D013196:Dihydrotestosterone / Q000378:metabolism; D004958:Estradiol / Q000378:metabolism; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007006:Hypogonadism / Q000378:metabolism*; D007118:Immunoassay; D016015:Logistic Models; D007986:Luteinizing Hormone / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone; D012738:Sex Hormone-Binding Globulin / Q000378:metabolism; D013739:Testosterone / Q000378:metabolism; D014807:Vitamin D / Q000031:analogs & derivatives / Q000378:metabolism; D014808:Vitamin D Deficiency / Q000378:metabolism*
chemical_list: D010281:Parathyroid Hormone; D012738:Sex Hormone-Binding Globulin; D013196:Dihydrotestosterone; D014807:Vitamin D; D013739:Testosterone; D004958:Estradiol; D007986:Luteinizing Hormone; C104450:25-hydroxyvitamin D