Calculated bioavailable testosterone levels and depression in middle-aged men

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 tower mean BT levels (3.51 +/- 1.69vs. 4.69 +/- 2.04nmot/L; p=0.008) and 17 levels (11.94 +/- 4.63 vs. 17.64 +/- 1.02nmot/L; p < 0.001) when compared to the control group. Biochemical hypogonadism (i.e., BT level <= 2.4 nmol/L or TT level <= 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. (c) 2006 Elsevier Ltd. All rights reserved.