Background: The aim of the present study is to evaluate the symptomatologic presentation of delusional compared to non-delusional major depressive episodes.
Methods: Two hundred and eighty-eight subjects suffering from mood disorder (144 bipolar, 133 unipolar) were assessed at admission by the Hamilton Depression Rating Scale (HAMD-21).
Results: Depressive symptomatology was more severe in the delusional sample, even after the exclusion of the items directly involved with delusional symptoms (P = 0.00002).
Conclusions: Our data support the hypothesis of delusional depression as a more severe form of mood disorder.