Fluoxetine-clonazepam cotherapy for anxious depression: an exploratory, post-hoc analysis of a randomized, double blind study.

Anxious depression, defined as major depressive disorder (MDD) accompanied by high levels of anxiety, seems to be both common and difficult to treat, with antidepressant monotherapy often yielding modest results. We sought to examine the relative benefits of antidepressant-anxiolytic cotherapy versus antidepressant monotherapy for patients with anxious depression versus without anxious depression. We conducted a post-hoc analysis of an existing dataset (N=80), from a 3-week, randomized, double-blind trial which demonstrated cotherapy with fluoxetine and clonazepam to result in superior efficacy than fluoxetine monotherapy in MDD. The present analysis involved examining whether anxious depression status served as a predictor and moderator of symptom improvement. Anxious depression status was not found to predict symptom improvement, or serve as a moderator of clinical improvement to cotherapy versus monotherapy. However, the advantage in remission rates in favor of cotherapy versus monotherapy was, numerically, much larger for patients with anxious depression (32.2%) than it was for patients without anxious MDD (9.7%). The respective number needed to treat statistic for these two differences in response rates were, approximately, one in three for patients with anxious depression versus one in 10 for patients without anxious depression. The efficacy of fluoxetine-clonazepam cotherapy compared with fluoxetine monotherapy was numerically but not statistically enhanced for patients with anxious depression than those without anxious depression.