An empirical study of psychosis in borderline personality disorder.

To assess the nature and prevalence of psychotic symptoms in borderline personality disorder, the authors reviewed the cases of 33 patients meeting DSM-III criteria for borderline personality disorder, using both "narrow" and "broad" definitions of psychosis. Only eight patients displayed psychotic symptoms meeting the "narrow" DSM-III definition; in all of these cases, the symptoms appeared to be attributable to either severe drug abuse or major affective disorder, present simultaneously with borderline personality disorder. The remaining patients displayed only "broadly defined" psychotic symptoms or symptoms that appeared to be under voluntary control. These findings weigh against the assumption that borderline personality disorder lies "on the border" of classical psychotic disorders.