Thyroid Axis in Major Depression

The primary hypothesis is that triiodothyronine (Cytomel) supplementation of the antidepressant sertraline (Zoloft) will result in a greater improvement in HAM-D scores compared to placebo in the treatment of Major Depressive Disorder (MDD). The goals of this proposal are to examine the relationship between Major Depressive Disorder (MDD) and abnormalities of the hypothalamic pituitary thyroid (HPT) axis. This protocol will systematically examine the value of supplemental triiodothyronine (T3, Cytomel) with sertraline (Zoloft), a selective serotonin reuptake inhibitor (SSRI) in the treatment of MDD. The focus will be on two overlapping populations: 1) those with evidence of HPT abnormalities, and 2) those who did not respond to a previous adequate SSRI trial