Persistent cortisol non-suppression after clinical recovery predicts symptomatic relapse in unipolar depression.

We assessed the length and the quality of remission of 13 unipolar endogenous depressed patients, DST non-suppressors before treatment, in a 2-year prospective study. During this period, we recorded stressful life events. Persistent dexamethasone non-suppression, after treatment and complete clinical recovery, correlated highly with early clinical relapse. All six non-normalizers but only one normalizer were rehospitalized within the following 2 years for a major depressive relapse. Persistent DST non-suppression was unrelated to any impact of drug discontinuation, the occurrence of stressful life events or the length of illness-free intervals in the patient's prior course of illness. Persistent DST non-suppression appears to have significant prognostic value.