Comorbidity in Patients with Narcissistic Personality Disorder in Comparison to Patients with Borderline Personality Disorder

Background: Patients with a narcissistic personality disorder (NPD) do not often consult a psychotherapist or psychiatrist because of their NPD, but rather, because of co-occurring psychiatric disorders, or higher general symptom stress. Until now there is no actual data about rates of co-occurrence disorders and general symptom stress. Objective: Which axis I and axis II disorders occur typically in NPD in comparison to patients with a borderline personality disorder (BPD)? How are general symptom stress and depressive symptoms related? Methods: Prevalence of co-occurring disorders (Structured Clinical Interview for DSM-IV for Axis I and Axis II) and general symptom stress (SCL-90-R) and depression (BDI) were investigated in 62 patients with a NPD, 62 patients with a BPD and 59 patients with a double diagnosis NPD/BPD. Results: Affective disorders (64.5%) and substance use disorders (35.5%) were the most comorbid psychiatric disorders in patients with NPD. Substance use disorders (p < 0.01) and post-traumatic stress disorder (PTSD) (p < 0.01) were more common in BPD than in NPD. In comparison to patients with the double diagnosis NPD/BPD major depression (p < 0.05) was more frequent in patients with NPD and substance use disorders (p < 0.001) and antisocial personality disorder (p < 0.001) were less common in patients with NPD. Gender effects were found in PTSD, bulimia nervosa, substance use disorders and antisocial personality disorder. Patients with NPD showed lowest rates of co-occurring disorders and lowest scores in general symptom stress and depression than the other two groups. Conclusions: In general, patients with NPD showed similar co-occurring disorders as patients with BPD, or with the co-diagnosis NPD and BPD, but they showed lower scores for general symptom stress and depression.