Psychotic features in chronic posttraumatic stress disorder and schizophrenia - Comparative severity

Psychotic features are frequent in combat veterans with chronic posttraumat ic stress disorder (PTSD), may correlate with severity of PTSD symptoms,;an d may reflect a distinct subtype of the disorder. These psychotic features include auditory and visual hallucinations and delusional thinking that is usually paranoid in nature. Psychotic features may be under-recognized in c hronic PTSD because patients are reluctant to report these symptoms and bec ause they may not have overt changes in affect or bizarre delusions charact eristic of other psychoses, e.g., schizophrenia. To further assess these ph enomena, we compared clinical ratings on the Positive and Negative Syndrome Scale (PANSS) and other assessments, including the Clinical Global Impress ion Scale and the Structured Clinical Interview with Psychotic Screen, in v eterans meeting DSM-nt criteria for chronic PTSD with well-defined comorbid psychotic features (N = 40) or chronic sckizophrenia (N = 40). The patient s with schizophrenia had modestly higher composite PANSS scores and positiv e symptom scores although average scores in both groups were moderate to se vere in intensity. Negative symptom and general psychopathology subscale sc ores were comparable in both groups. Regarding specific positive symptoms, hallucinations were comparable between groups in severity; however, schizop hrenia patients had slightly more intense delusions and conceptual disorgan ization. These data further validate the occurrence of positive as well as negative symptoms of psychosis in chronic PTSD in a range of severity that may approach that of patients with schizophrenia. Although meeting DSM-IV c riteria for two different major psychiatric disorders, these two patient po pulations were remarkably similar with respect to not only positive but als o negative symptoms.