Psychotic features and illness severity in combat veterans with chronic posttraumatic stress disorder.

BACKGROUND Psychotic symptoms may be present in up to 40% of patients with combat-related posttraumatic stress disorder (PTSD). In this study, we hypothesized that severity of psychotic symptoms would also reflect severity of PTSD symptoms in patients with well-defined psychotic features. METHODS Forty-five Vietnam combat veterans with PTSD but without a primary psychotic disorder diagnosis underwent a Structured Clinical Interview for DSM-III-R with Psychotic Screen, and the Clinician Administered PTSD Scale (CAPS). Patients identified as having psychotic features (PTSD-P), (n = 22) also received the Positive and Negative Syndrome Scale (PANSS) and the Hamilton Depression Rating Scale (HDRS). RESULTS There was a significant positive correlation between the CAPS and PANSS global ratings (p < .001) and the HDRS and PANSS (p < .03) in the PTSD-P patients. Many CAPS and PANSS subscales also demonstrated significant intercorrelations; however, the CAPS-B subscale (reexperiencing) and the PANSS positive symptom scale were not correlated, suggesting that psychotic features may not necessarily be influenced or accounted for by more severe reexperiencing symptoms. Fifteen (68%) of the PTSD-P patients had major depression (MDD). Both CAPS and PANSS ratings were significantly higher in the PTSD-P patients with comorbid MDD. CONCLUSIONS As postulated, patients with more severe psychosis ratings are likely to have more severe PTSD disease burden if psychotic features are present. This study further documents the occurrence of psychotic features in PTSD that are not necessarily due to a primary psychotic disorder, suggesting that this may be a distinct subtype; however, a significant interaction likely exists between PTSD, depression, and psychotic features.