666 Personality Disorders
give the impression of borderline personality disorder. Such situations are characterized by
emotional instability, “existential” dilemmas, uncertainty, anxiety- provoking choices, con-
flicts about sexual orientation, and competing social pressures to decide on careers. 
Gender-Related Diagnostic Issues
Borderline personality disord er is diagnosed predominantly (about 75%) in females.
Differential Diagnosis
Depressive and bipolar disorders. Borderline personality disorder often co-occurs with
depressive or bipolar disorders, and when criteria for both are met, both may be diagnosed.
Because the cross-sectional presentation of bo rderline personality disorder can be mimicked
by an episode of depressive or bipolar disord er, the clinician should avoid giving an addi-
tional diagnosis of borderline personality diso rder based only on cr oss-sectional presenta-
tion without having documented that the pattern of behavior had an early onset and a long-
standing course.
Other personality disorders. Other personality disorders ma y be confused with border-
line personality disorder because they have certain features in  common. It is therefore im-
portant to distinguish among these disorders based on differences in their characteristic
features. However, if an individual has person ality features that meet criteria for one or
more personality disorders in addition to bord erline personality disorder, all can be diag-
nosed. Although histrionic personality disorder can also be characterized by attention seek-
ing, manipulative behavior, an d rapidly shifting emotions, borderline personality disorder
is distinguished by self-destructiveness, an gry disruptions in close relationships, and
chronic feelings of deep emptiness and loneline ss. Paranoid ideas or illusions may be pres-
ent in both borderline personality disorder an d schizotypal personality disorder, but these
symptoms are more transient, in terpersonally reactive, and responsive to external structur-