title: Vitamin D levels and bone mineral density: are LH levels involved in the pathogenesis of bone impairment in hypogonadal men?
abstract: BACKGROUND
  Osteoporosis is a major public health problem also in men and it recognizes hypogonadism as a major cause.
  
  
  OBJECTIVE
  To investigate the possible pathogenetic mechanisms on bone impairment in male hypogonadism and on its improvement in response to testosterone replacement treatment (TRT).
  
  
  METHODS
  We retrospectively investigated the hormonal profile and bone mineral density (BMD), evaluated by DXA, in 17 middle-aged hypogonadal men treated for at least 5 years with TRT, compared with 21 recently diagnosed untreated hypogonadal males and 18 age- and BMI-matched healthy subjects.
  
  
  RESULTS
  No significant differences in clinical, biochemical and densitometric parameters were found among the three groups, with the exception of 25-OH vitamin D levels that were significantly higher in healthy subjects compared with hypogonadal patients. Untreated patients affected by central hypogonadism, despite similar hormonal levels, displayed significantly lower BMD and decreased LH and 25-OH vitamin D levels, compared with patients with primary hypogonadism. Among the treated patients, BMD parameters were similar regardless of the formulation of TRT.
  
  
  CONCLUSIONS
  A recent history of central hypogonadism, compared with primary hypogonadism, appears to adversely affect bone health independently of gonadal steroids levels. This could be due to lower LH levels and consequent reduction of vitamin D 25-hydroxylation in the testis.
authors.affiliation: Division of Endocrinology, Polytechnic University of Marche, Ospedali Riuniti Umberto I-GM Lancisi-G Salesi, Ancona, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Gioia
authors.forename: L
authors.initials: L
authors.lastname: Ceccoli
authors.forename: V
authors.initials: V
authors.lastname: Ronconi
authors.forename: F
authors.initials: F
authors.lastname: Turchi
authors.forename: M
authors.initials: M
authors.lastname: Marcheggiani
authors.forename: M
authors.initials: M
authors.lastname: Boscaro
authors.forename: G
authors.initials: G
authors.lastname: Giacchetti
authors.forename: G
authors.initials: G
authors.lastname: Balercia
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D015519:Bone Density / Q000502:physiology*; D006801:Humans; D007006:Hypogonadism / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology; D007986:Luteinizing Hormone / Q000097:blood*; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology; D012189:Retrospective Studies; D014807:Vitamin D / Q000097:blood*
chemical_list: D015415:Biomarkers; D014807:Vitamin D; D007986:Luteinizing Hormone