Cluster B personality disorders are the most common in psychiatric patients and are correlated with specific characteristics. However, dissimilarities may be noticed between different personality types.

This study aimed to compare sociodemographic and clinical features of patients with varied types of this cluster.

It's a comparative study held in the psychiatric outpatient unit. All five years first time attendances to the unit were retrospectively examined in order to identify those with diagnosis of cluster B personality disorder according to DSM-IV criteria (N=81). Statistical comparisons were performed for sociodemographic features, medical history and axis I comorbidity.

Antisocial personality was the most common (n=32), followed by histrionic (n=28), then borderline personality (n=19).

Patients with antisocial personality were mainly of male gender (p<10-4) and had more antecedents of incarcerations (p<10-4) than the remainder.

Patients with borderline personality had reported less alcohol (p=0.035) and prescribed drugs (p=0.01) use than patients with antisocial personality and more alcohol use (p=0.013) than patients with histrionic personality. History of alcohol (p<10-4), cannabis (0.002) and prescribed drugs (p<10-4) use was more frequent in antisocial compared to histrionic personality. Also, patients with histrionic personality had more conversion disorder than those with antisocial personality (p=0.001).

Cluster B personality disorders seem to share similar family and personal past medical history, but are very different in matter of substance use and comorbid conversion disorder. These findings support the idea that adapted psychiatric care is needed for each type of cluster B personality disorder.