Cushings syndrome is severely elevated cortisol, normally caused by steriod treatment or a pitiutary adanoma, the increase in cortisol from depression isn't significant in compraison, just enough to jamble brain chemistry.
Raised Cortisol isn't found in most patients with depression and only about half of severely depressed patients have it, mostly those who fit the melcholic sub-type suffering from psychotic depression.
There is no point in getting your cortisol tested unless an endocrineologist has reason to suspect cushings. It won't give you any extra treatment options. Most (if not all) of the cortisol receptor antagonists being trialed for depression have already been withdrawan due to lack of effiacy.
That being said in psychotic depression and severe hospitalized depression with signficant psychomotor abnormalities (agitated or retarded (typically the patient will be psychotic anyway or at least showing delusion like symptoms) and cataonic depression cortisol antagonists may have a place in treatment if its refactory to standard treatments or as agumentation in partial response.
Edited by Tom_, 23 May 2014 - 09:32 AM.