Does comorbid posttraumatic stress disorder affect the severity and course of psychotic major depressive disorder?
GROUND: Major depressive disorder (MDD) and posttraumatic stress disorder (PTSD) are commonly comorbid conditions that result in greater severity, chronicity, and impairment compared with either disorder alone. However, previous research has not systematically explored the potential effects of the psychotic subtyping of MDD and comorbid PTSD. METHOD: The sample in this retrospective case-control study conducted from December 1995 to August 2006 consisted of psychiatric outpatients with DSM-IV-diagnosed psychotic MDD with PTSD, psychotic MDD without PTSD, or nonpsychotic MDD with PTSD presenting for clinic intake. Clinical indices of severity, impairment, and history of illness were assessed by trained diagnosticians using the Structured Clinical Interview for DSM-IV Axis I Disorders supplemented by items from the Schedule for Affective Disorders and Schizophrenia. RESULTS: In terms of current severity and impairment, the psychotic MDD with PTSD (n = 34) and psychotic MDD only (n = 26)
