Psychobiological predictors of antidepressant drug response.

Forty-nine patients with major depression and a reduced (less than 65.0 minute) REM latency were treated in a randomized, double-blind study with either amitriptyline or alprazolam. Predictors of response were sought for the whole group and for each drug cell individually. A longer current episode and a higher Beck Depression Inventory to Hamilton Rating Scale ratio were predictive of a poorer response for the whole group and for the alprazolam group. A longer current episode was also predictive of a poor response to amitriptyline. These data suggest that (1) a longer current episode and (2) a greater level of self-reported compared to clinician-observed symptoms correlate with a poorer response to antidepressant medications.