Posttraumatic stress disorder and negative symptoms of schizophrenia.

Posttraumatic stress disorder (PTSD) is highly comorbid with schizophrenia and may be associated with higher levels or lower levels of negative symptoms. In the current study, we attempted to clarify the relationship between PTSD and negative symptoms by examining the proportion of patients meeting various negative symptom criteria in a sample of patients diagnosed with schizophrenia alone or schizophrenia and comorbid PTSD. Results indicated that the presence of PTSD in schizophrenia was associated with increased secondary negative symptoms, with the deficit syndrome (DS) and primary negative symptoms associated with lower rates of current and lifetime diagnoses of PTSD. Furthermore, the deficit/nondeficit classification provided greater differentiation of PTSD symptoms than did negative symptoms defined more broadly using the Scale for the Assessment of Negative Symptoms or primary vs secondary distinctions. These findings suggest that DS patients are at a uniquely low risk for PTSD.