Refractory depression: prediction of non-response by clinical indicators.

The prediction of non-response in a well-defined group of 76 inpatients with a major depressive syndrome was made on the basis of clinical data. While agitation, anxiety, presence of delusions and bipolarity were significant factors, previously considered predictors (e.g. endogenous subtype, duration of present episode, number of previous episodes) did not contribute to the successful discrimination of response in this group at three levels: Clear-cut response, partial response and non-response. Since this investigation has carefully controlled for drug withdrawal and washout phases, medical complications and antidepressant drug compliance, the results of earlier studies may need to be reevaluated.