Agitated “unipolar” depression re-conceptualized as a depressive mixed state: implications for the antidepressant-suicide controversy

The data reported herein, placed in the setting of the literature reviewed in the discussion suggest that the reports of increased risk of suicidal ideation and/or behavior in some depressed patients treated by antidepressant monotherapy or combinations thereof might be attributed to baseline psychomotor activation/agitation as part of an unrecognized bipolar mixed state. Whether antidepressants induce de novo suicidality in MDD cannot be answered without adequately powered prospective double-blind studies, unlikely to be conducted because of ethical constraints. Nonetheless, we submit that agitated, activated, or otherwise excited depressions (which we consider as depressive mixed states) overlap considerably with the so-called antidepressant “activation syndrome.” Furthermore, the rare occurrence of suicidality on antidepressants should not obscure the fact that the advent of the new antidepressants is associated with worldwide decline in suicide rates. We finally wish to point out that our formal nosology (i.e. DSM-IV and ICD-10), in its failure to recognize the bipolar nature of depressive mixed states, thereby fails to shield pseudo-unipolar patients from antidepressant monotherapy, which is inappropriate for such patients.