Clinical research
The relationship between borderline
personality disorder and bipolar disorder
Mark Zimmerman, MD; Theresa A. Morgan, PhD
Introduction
T he under-recognition of bipolar disorder in
patients presenting for the treatment of depression has
been identified as a significant clinical problem.1-11 The
diagnosis of bipolar disorder is often delayed, with the
time between initial treatment seeking and the correct
diagnosis often taking more than 10 years.12,13 The treat-
It is clinically important to recognize both bipolar disorder ment and clinical implications of the failure to recognize
and borderline personality disorder (BPD) in patients seek- bipolar disorder in depressed patients are significant,
ing treatment for depression, and it is important to dis- and include the underprescription of mood-stabilizing
tinguish between the two. Research considering whether medications, an increased risk of rapid cycling, and
BPD should be considered part of a bipolar spectrum increased costs of care.4,14-16 As a result of the potential
reaches differing conclusions. We reviewed the most stud- morbidity associated with a delay in diagnosis, experts
ied question on the relationship between BPD and bipo- have called for improved recognition of bipolar disor-
lar disorder: their diagnostic concordance. Across studies, der,1,6 and screening scales have been developed and rec-
approximately 10% of patients with BPD had bipolar I dis- ommended to facilitate the identification of bipolar dis-
order and another 10% had bipolar II disorder. Likewise, order.17-19
approximately 20% of bipolar II patients were diagnosed Borderline personality disorder (BPD) is a common
with BPD, though only 10% of bipolar I patients were comorbidity in depressed patients that is also under-
diagnosed with BPD. While the comorbidity rates are sub- diagnosed.20 Compared with patients with major depres-
stantial, each disorder is nontheless diagnosed in the sive disorder (MDD) without BPD, patients with MDD
absence of the other in the vast majority of cases (80% to and BPD also have excess psychosocial morbidity.21,22
90%). In studies examining personality disorders broadly, The recognition of BPD is clinically important because
other personality disorders were more commonly diag- of the availability of specific psychotherapies that are
nosed in bipolar patients than was BPD. Likewise, the con-
verse is also true: other axis I disorders such as major Keywords: bipolar disorder; borderline personality disorder; bipolar spectrum
depression, substance abuse, and post-traumatic stress dis-
Author affiliations: Department of Psychiatry and Human Behavior, Brown
order are also more commonly diagnosed in patients with Medical School, Providence, Rhode Island, USA
BPD than is bipolar disorder. These findings challenge the
Address for correspondence: Mark Zimmerman, MD, Bayside Medical Center,
notion that BPD is part of the bipolar spectrum. 235 Plain Street, Providence, RI 02905, USA
© 2013, AICH Dialogues Clin Neurosci. 2013;15:155-169. (e-mail: )
Copyright © 2013 AICH. All rights reserved 155 www.dialogues-cns.org
, Clinical research
effective23,24 and the possible overprescription of med- Methodological issues in
ications that have little benefit and carry the risk of med- personality disorder assessment
ically significant side effects.25
Because of the potential treatment implications, it is Any review of a topic involving personality disorders
clinically important to recognize both bipolar disorder needs to consider assessment methodology, because
and BPD in patients seeking treatment for depression, assessment issues can have a significant impact on the find-
and it is important to distinguish between the two. ings. In short, there should be some consideration of the
However, this presupposes that each is a valid diagnos- who, what, and when of personality disorder assessment.
tic entity. During the past 20 years there have been To be sure, these are also issues in the evaluation of Axis I
increasing suggestions that BPD should be conceptual- disorders, though they have not been studied as much as
ized as part of the spectrum of bipolar disorder. they have been studied in the personality disorder field.
Advocates of the bipolar spectrum suggest that treat- Who should be questioned when assessing personality
ments that have been found effective in treating bipo- disorders–the target individual or someone who knows
lar disorder should be used when treating patients with the target individual well? The evaluation of personality
BPD because of its inclusion on the bipolar spectrum.6,26-28 disorders presents special problems that may require the
Literature reviews considering whether BPD belongs to use of informants. In contrast to the symptoms of major
the bipolar spectrum have reached differing conclusions. Axis I disorders, the defining features of personality dis-
Smith et al29 suggested that a strong case could be made orders are based on an extended longitudinal perspective
that a significant percentage of patients with BPD fall of how individuals act in different situations, how they
into the bipolar spectrum, and Belli et al30 concluded perceive and interact with a constantly changing envi-
that the two disorders are closely linked in phenome- ronment, and the perceived reasonableness of their
nology and treatment response. Antoniadis et al31 and behaviors and cognitions. Only a minority of the person-
Coulston et al32 did not draw a conclusion regarding ality disorder criteria are discrete, easily enumerated
BPD’s inclusion on the bipolar spectrum, whereas Paris behaviors. For any individual to describe their normal
et al33 and Dolan-Sewell et al34 concluded that empirical personality they must be somewhat introspective and
evidence did not support BPD’s link to the bipolar spec- aware of the effect their attitudes and behaviors have on
trum. Sripada and Silk,35 reviewing neuroimaging stud- others. But insight is the very thing usually lacking in
ies, noted that there were some areas of overlap and individuals with a personality disorder. DSM-IV notes
some differences between BPD and bipolar disorder. that the characteristics defining a personality disorder
Some of the authors of these reviews noted that few may not be considered problematic by the affected indi-
studies have directly compared patients with bipolar vidual (ie, ego-syntonic) and suggests that information be
disorder and BPD, and they called for such empirical obtained from informants. Research comparing patient
data to help clarify the relationship between the two and informant report of personality pathology has found
disorders.32,35 marked disagreement between the two sources of infor-
In the present review we focus on the most studied ques- mation.36-39 Only one of the studies examining the fre-
tion on the relationship between BPD and bipolar dis- quency of personality disorders in patients with bipolar
order—their diagnostic concordance. More than 30 stud- disorder examined the impact of informant assessment
ies have examined the frequency of bipolar disorder in on the rates of personality disorder diagnoses.40 Peselow
patients with borderline personality disorder, or the fre- et al40 presented personality disorder rates based on inde-
quency of BPD in patients with bipolar disorder. We pendent patient and informant interviews, and we have
address the following questions: (i) What is the fre- included in Table I the results based on the patient infor-
quency of each disorder when the other is present? (ii) mation in order to be consistent with other studies.
Is the level of co-occurrence elevated? That is, is the What measures should be used to diagnose personality
prevalence of BPD significantly higher in patients with disorders? Several instruments exist, and while there is
bipolar disorder than in other psychiatric disorders? (iii) no evidence that any one interview schedule is more reli-
Is BPD the most common personality disorder in bipo- able or valid than another, there is consistent evidence
lar patients or are other personality disorders more fre- that prevalence rates are higher based on self-adminis-
quent? tered scales than clinician interviews.41-43
156
The relationship between borderline
personality disorder and bipolar disorder
Mark Zimmerman, MD; Theresa A. Morgan, PhD
Introduction
T he under-recognition of bipolar disorder in
patients presenting for the treatment of depression has
been identified as a significant clinical problem.1-11 The
diagnosis of bipolar disorder is often delayed, with the
time between initial treatment seeking and the correct
diagnosis often taking more than 10 years.12,13 The treat-
It is clinically important to recognize both bipolar disorder ment and clinical implications of the failure to recognize
and borderline personality disorder (BPD) in patients seek- bipolar disorder in depressed patients are significant,
ing treatment for depression, and it is important to dis- and include the underprescription of mood-stabilizing
tinguish between the two. Research considering whether medications, an increased risk of rapid cycling, and
BPD should be considered part of a bipolar spectrum increased costs of care.4,14-16 As a result of the potential
reaches differing conclusions. We reviewed the most stud- morbidity associated with a delay in diagnosis, experts
ied question on the relationship between BPD and bipo- have called for improved recognition of bipolar disor-
lar disorder: their diagnostic concordance. Across studies, der,1,6 and screening scales have been developed and rec-
approximately 10% of patients with BPD had bipolar I dis- ommended to facilitate the identification of bipolar dis-
order and another 10% had bipolar II disorder. Likewise, order.17-19
approximately 20% of bipolar II patients were diagnosed Borderline personality disorder (BPD) is a common
with BPD, though only 10% of bipolar I patients were comorbidity in depressed patients that is also under-
diagnosed with BPD. While the comorbidity rates are sub- diagnosed.20 Compared with patients with major depres-
stantial, each disorder is nontheless diagnosed in the sive disorder (MDD) without BPD, patients with MDD
absence of the other in the vast majority of cases (80% to and BPD also have excess psychosocial morbidity.21,22
90%). In studies examining personality disorders broadly, The recognition of BPD is clinically important because
other personality disorders were more commonly diag- of the availability of specific psychotherapies that are
nosed in bipolar patients than was BPD. Likewise, the con-
verse is also true: other axis I disorders such as major Keywords: bipolar disorder; borderline personality disorder; bipolar spectrum
depression, substance abuse, and post-traumatic stress dis-
Author affiliations: Department of Psychiatry and Human Behavior, Brown
order are also more commonly diagnosed in patients with Medical School, Providence, Rhode Island, USA
BPD than is bipolar disorder. These findings challenge the
Address for correspondence: Mark Zimmerman, MD, Bayside Medical Center,
notion that BPD is part of the bipolar spectrum. 235 Plain Street, Providence, RI 02905, USA
© 2013, AICH Dialogues Clin Neurosci. 2013;15:155-169. (e-mail: )
Copyright © 2013 AICH. All rights reserved 155 www.dialogues-cns.org
, Clinical research
effective23,24 and the possible overprescription of med- Methodological issues in
ications that have little benefit and carry the risk of med- personality disorder assessment
ically significant side effects.25
Because of the potential treatment implications, it is Any review of a topic involving personality disorders
clinically important to recognize both bipolar disorder needs to consider assessment methodology, because
and BPD in patients seeking treatment for depression, assessment issues can have a significant impact on the find-
and it is important to distinguish between the two. ings. In short, there should be some consideration of the
However, this presupposes that each is a valid diagnos- who, what, and when of personality disorder assessment.
tic entity. During the past 20 years there have been To be sure, these are also issues in the evaluation of Axis I
increasing suggestions that BPD should be conceptual- disorders, though they have not been studied as much as
ized as part of the spectrum of bipolar disorder. they have been studied in the personality disorder field.
Advocates of the bipolar spectrum suggest that treat- Who should be questioned when assessing personality
ments that have been found effective in treating bipo- disorders–the target individual or someone who knows
lar disorder should be used when treating patients with the target individual well? The evaluation of personality
BPD because of its inclusion on the bipolar spectrum.6,26-28 disorders presents special problems that may require the
Literature reviews considering whether BPD belongs to use of informants. In contrast to the symptoms of major
the bipolar spectrum have reached differing conclusions. Axis I disorders, the defining features of personality dis-
Smith et al29 suggested that a strong case could be made orders are based on an extended longitudinal perspective
that a significant percentage of patients with BPD fall of how individuals act in different situations, how they
into the bipolar spectrum, and Belli et al30 concluded perceive and interact with a constantly changing envi-
that the two disorders are closely linked in phenome- ronment, and the perceived reasonableness of their
nology and treatment response. Antoniadis et al31 and behaviors and cognitions. Only a minority of the person-
Coulston et al32 did not draw a conclusion regarding ality disorder criteria are discrete, easily enumerated
BPD’s inclusion on the bipolar spectrum, whereas Paris behaviors. For any individual to describe their normal
et al33 and Dolan-Sewell et al34 concluded that empirical personality they must be somewhat introspective and
evidence did not support BPD’s link to the bipolar spec- aware of the effect their attitudes and behaviors have on
trum. Sripada and Silk,35 reviewing neuroimaging stud- others. But insight is the very thing usually lacking in
ies, noted that there were some areas of overlap and individuals with a personality disorder. DSM-IV notes
some differences between BPD and bipolar disorder. that the characteristics defining a personality disorder
Some of the authors of these reviews noted that few may not be considered problematic by the affected indi-
studies have directly compared patients with bipolar vidual (ie, ego-syntonic) and suggests that information be
disorder and BPD, and they called for such empirical obtained from informants. Research comparing patient
data to help clarify the relationship between the two and informant report of personality pathology has found
disorders.32,35 marked disagreement between the two sources of infor-
In the present review we focus on the most studied ques- mation.36-39 Only one of the studies examining the fre-
tion on the relationship between BPD and bipolar dis- quency of personality disorders in patients with bipolar
order—their diagnostic concordance. More than 30 stud- disorder examined the impact of informant assessment
ies have examined the frequency of bipolar disorder in on the rates of personality disorder diagnoses.40 Peselow
patients with borderline personality disorder, or the fre- et al40 presented personality disorder rates based on inde-
quency of BPD in patients with bipolar disorder. We pendent patient and informant interviews, and we have
address the following questions: (i) What is the fre- included in Table I the results based on the patient infor-
quency of each disorder when the other is present? (ii) mation in order to be consistent with other studies.
Is the level of co-occurrence elevated? That is, is the What measures should be used to diagnose personality
prevalence of BPD significantly higher in patients with disorders? Several instruments exist, and while there is
bipolar disorder than in other psychiatric disorders? (iii) no evidence that any one interview schedule is more reli-
Is BPD the most common personality disorder in bipo- able or valid than another, there is consistent evidence
lar patients or are other personality disorders more fre- that prevalence rates are higher based on self-adminis-
quent? tered scales than clinician interviews.41-43
156
