title: Calculated bioavailable testosterone levels and depression in middle-aged men.
abstract: BACKGROUND
  The association between circulating total testosterone (TT) levels and depressive symptoms remains unclear. We sought to determine the relationship between physiologically active bioavailable testosterone (BT) and depressive symptoms in middle-aged men with and without major depressive disorder (MDD).
  
  
  METHODS
  We assessed and compared calculated BT levels in two groups of middle-aged men (40-65 years): untreated subjects meeting DSM-IV-TR-defined criteria for a major depressive episode as part of major depressive disorder (N=44) and a matched non-depressed control group (N=50).
  
  
  RESULTS
  Depressed men had lower mean BT levels (3.51+/-1.69 vs. 4.69+/-2.04 nmol/L; p=0.008) and TT levels (11.94+/-4.63 vs. 17.64+/-1.02 nmol/L; p<0.001) when compared to the control group. Biochemical hypogonadism (i.e., BT level< or =2.4 nmol/L or TT level< or =12.14 nmol/L) was also more prevalent in depressed men vs. non-depressed controls (34% vs. 6%, p<0.001; 61% vs. 14%, p<0.001, respectively).
  
  
  CONCLUSIONS
  Changes in physiologically active BT concentration may be a vulnerability factor for depressive symptoms in middle-aged depressed men.
authors.affiliation: Department of Psychiatry, University of Toronto, Toronto, Ontario, Canada. roger.mcintyre@uhn.on.ca
authors.forename: Roger S
authors.initials: RS
authors.lastname: McIntyre
authors.forename: Deborah
authors.initials: D
authors.lastname: Mancini
authors.forename: Beata S
authors.initials: BS
authors.lastname: Eisfeld
authors.forename: Joanna K
authors.initials: JK
authors.lastname: Soczynska
authors.forename: Larry
authors.initials: L
authors.lastname: Grupp
authors.forename: Jakub Z
authors.initials: JZ
authors.lastname: Konarski
authors.forename: Sidney H
authors.initials: SH
authors.lastname: Kennedy
mesh_terms: D000328:Adult; D000342:Affective Symptoms / Q000097:blood; D000368:Aged; D016022:Case-Control Studies; D003866:Depressive Disorder / Q000097:blood* / Q000150:complications / Q000523:psychology; D006801:Humans; D007006:Hypogonadism / Q000097:blood* / Q000150:complications; D008297:Male; D016555:Matched-Pair Analysis; D008875:Middle Aged; D012720:Severity of Illness Index; D013739:Testosterone / Q000097:blood*
chemical_list: D013739:Testosterone