The Co-Occurrence of Trauma Related Disorder and Borderline Personality Disorder: AQ Study on a Clinical Sample of Patients Seeking Psychotherapy Treatment.

The nature of the relationship between borderline personality disorder (borderline PD), post-traumatic stress disorder (PTSD) and complex PTSD remains controversial. In this study we attempted to investigate the association between traumatic events and borderline PD and the co-occurrence of complex PTSD, PTSD and borderline PD. Finally, we tested the association between complex PTSD and PTSD diagnoses and other DSM-5 Section II personality disorders. In a sample of 416 patients, we administered the International Trauma Questionnaire (ITQ) to evaluate the PTSD/complex PTSD diagnoses and the Structured Clinical Interview for DSM-5 Personality Disorders (SCID-5-PD) and the Personality Diagnostic Questionnaire- 4+ (PDQ-4+) to assess borderline PD and other PDs. One hundred-twenty-three participants reported experiencing one or more traumatic events. Our findings show that the presence of adverse events does not represent a risk factor for borderline PD assessed using both SCID-5-PD and PDQ4+. A co-occurrence of borderline PD diagnoses and complex PTSD/PTSD diagnoses has not been observed. We found a significant association only between complex PTSD and schizoid personality disorder assessed using PDQ4+. Our findings suggest relevant clinical implications for the development of effective treatment for complex PTSD, PTSD and borderline PD.