In some different studies, a high prevalence of posttraumatic stress disorder (PTSD) has been found in patients with several mental illness (SMI): schizophrenia, schizoaffective and bipolar disorder.

Evaluate the prevalence and correlates of PTSD in a sample of patients with SMI.

Adult patients with schizophrenia, schizoaffective disorder or bipolar I disorder were enrolled.

Patients who score 3 or more in conceptual disorganisation, hallucinations and/or unusual contents of thinking and 4 in another item of the Brief Psychiatric Rating Scale (BPRS) were excluded.

• Sociodemographic data

• Traumatic Live Events Questionnarie. Kubany ang Hayne, 2001.

• Distressing Event Questionnaire. Kubany anb Haynes, 2001, related to PTSD diagnostic DSM-IV criteria.

• 102 patients were included.

• The diagnostic subgrup of SMI patients were: 40 bipolar disorder, 52 schizophrenia and 10 schizoaffective desorder.

• The prevalence of PTSD was found in 15.1%: Criterion B (reexperiencing) 34.4%, Criterion C (avoindance and numbing) 27.1%, Criterion D (hyperarousal) 27.1%.

• The PTSD was more prevalent in females: 21.7% versus 8.5% (p 0.074). Only in criterium of hyperarousal the differences of gender were significatives (p 0.02).

• There were no significative differences in dignostic subgrups (p 0.381).

• Patients with PTSD had some suicide attempt history in 64.3% versus in 35.7% the patients without PTSD (p 0.042).

The comorbidity of PTSD in SMI was found in a fifteen percent, and only three patients had been diagnostiqued.

PTSD is significantly related to history of suicide attempts in patients with SMI.