Symptoms as predictors of response in depression

Sertraline, a novel selective serotonin re-uptake inhibitor, has been proven as effective as amitriptyline and imipramine, and more effective than placebo, in double-blind controlled studies in patients with major depressive disorder. The question 'Do symptoms predict response to treatment?' is an important one in clinical practice. In order to try and answer this question, four double-blind clinical trials in major depressive disorder have been examined for clinically important symptoms and subgroups at entry to the studies. The Hamilton Depression Rating Scale (HAM-D, 17-item) was used throughout and the data for sertraline-treated patients were split in several different ways. The response to treatment was defined as the percentage of patients achieving a CGI-improvement score of 1 or 2 at the end of treatment. Patients with severe depression at entry had a response rate of > 80%, which was comparable to that of patients with moderate depression. A similar response rate was seen in the presence of DSM-III-defined melancholia, high anxiety, insomnia, psychomotor agitation or retardation. Finally, in order to examine the effect of old age on the response to treatment, one of the four studies, which included only patients aged 65 or older, was examined separately. In this study responders were defined as those with >50% reduction in baseline HAM-D at the end of treatment. Approximately 70% were found to be responders in both the moderate and severe depression subgroups.