Depressive disorder and depression within schizophrenia spectrum disorders: are they the same?

Abstract

Depressive states are a prevalent condition in mental disorders other than depressive disorders, which raises the question of whether or not depression in non-depressive disorders and depressive disorders has the same clinical and biological meaning. The aim of this study was to test the hypothesis that depression in schizophrenia spectrum disorders and depressive disorders does have the same characteristics regarding gender distribution and family history of mood disorders in first-degree relatives. The study sample was made up of 660 psychotic patients who were assessed for alternative definitions of depressive states. The pattern of gender distribution and family antecedents of mood disorders in those patients having depressive symptoms or syndromes was very similar to that reported in depressive disorders, and more specifically to depression in patients with schizophrenia spectrum disorders. These data support the hypothesis that depressions in schizophrenia spectrum disorders do have the same biological meaning as in depressive disorders.