To Be or Not to Be a Bipolar Disorder Patient Problems With Diagnosis Marianna Mazza, MD, PhD, Marco Di Nicola, MD, PhD, Luigi Janiri, MD, and Pietro Bria, MD Abstract: The diagnosis of bipolar disorder (BD) is predominantly clinical. Some authors have suggested that BD is underdiagnosed and that many pa- tients, particularly those with major depressive disorder, actually have BD. Some studies have suggested that BD is wrongly diagnosed, probably because of the idea of a ‘‘bipolar spectrum.’’ To address this potential overdiagnosis, clinicians should carefully and systematically assess whether symptoms are included in diagnostic criteria and include the individual context of the patient. Key Words: Overdiagnosis, underdiagnosis, bipolar disorder, borderline (J Nerv Ment Dis 2013;201: 435Y437) A s is the case for all psychiatric disorders, bipolar disorder (BD) lacks pathophysiological indicators or tests that provide a crite- rion standard for diagnosis. Its diagnosis, therefore, remains pre- dominantly clinical (Iordache and Low, 2010). Some authors have suggested that BD is underdiagnosed and that many patients, par- ticularly those with major depressive disorder, actually have BD (Bowden, 2001). The treatment and clinical implications of the fail- ure to recognize BD in patients with depression include the un- derprescription of mood-stabilizing medications, an increased risk for rapid cycling, and increased costs of care (Ghaemi et al., 2000). On the other hand, some studies have suggested that BD is also overdiagnosed (Hirschfeld et al., 2005; Zimmerman et al., 2008). Looking at chart records, BD is often misdiagnosed as a psychotic disorder (Meyer and Meyer, 2009), or there is a tendency to overdiagnose BD among pa- tients with substance use disorder for the presence of mood instability and high-risk behaviors (Goldberg et al., 2008). One reason for misdiagnoses could be that, in routine practice, clinicians use a heuristic approach instead of strictly adhering to diag- nostic criteria. The idea of a ‘‘bipolar spectrum’’ remains controversial because of the lack of widely accepted definitions, the concern that spectrum definitions might subsume cases with nonbipolar disorders, the worry that ‘‘diagnostic creep’’ may lead practitioners to overdiag- nose BD in marginal cases, and the worry that more diagnoses of bi- polar spectrum may increase aggressive pharmacotherapy (Youngstrom et al., 2010). Nevertheless, it seems that a correct diagnosis of BD does not depend on a specific criterion but on the total number of criteria. Clinicians seem to follow the additive model when making diagnoses (Wolkenstein et al., 2011). BD and Borderline Personality Disorder In 2008, Zimmerman et al. conducted the largest study of BD underdiagnosis and overdiagnosis, as part of the Rhode Island Methods to Improve Diagnostic Assessment and Services project. They found that slightly more than 20% of the sample reported that they had been previously diagnosed as having BD, significantly higher than the 12.9% rate based on the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). BD was also underdiagnosed in some patients. Three times as many patients had been overdiagnosed as had been underdiagnosed (82 vs. 27, as reported by author). In a follow-up study, the same group found that nearly 40% of the patients diagnosed with DSM-IV borderline personality disorder had been overdiagnosed with BD (Zimmerman, 2010). In borderline personality disorder, the mood swings are often triggered by interpersonal stressors (e.g., rejection) and a particular mood is usually less sustained than in BD (American Psychiatric As- sociation, Work Group on Borderline Personality Disorder, 2001). Both BD II and borderline personality disorder encompass irritability, im- pulsivity, and affective lability. However, BP II seems to be associated more with attentional impulsiveness (e.g., inability to focus on a task, racing thoughts), whereas borderline personality disorder is more re- lated to nonplanning impulsiveness (e.g., inability to think through consequences of actions) and seems to be associated with greater hostility (Manning, 2010). Finally, in patients with borderline person- ality disorder, depressive symptoms show only marginal improvement with antidepressants, and these agents never lead to remission of the disorder (Paris, 2011). As previously described, the phenomenological features of BD and borderline personality disorder overlap, in particu- lar, mood fluctuations and impulsivity, and, in fact, these two disorders frequently co-occur (Abe et al., 2011). However, notwithstanding a statistical association of BD and borderline personality disorder, most individuals with one of these disorders are not diagnosed with the other. Zimmerman et al. (2010b) affirm that the increased availability of medications to treat BD and the accompanying marketing efforts are chiefly responsible for the phenomenon of false-positive BD diag- noses. On the other hand, it is possible that clinicians are inclined to diagnose disorders that they feel more comfortable treating. For ex- ample, in patients with mood instability who do not meet criteria for a hypomanic episode, physicians are inclined to diagnose BD, a po- tentially medication-responsive disorder, rather than borderline per- sonality disorder, which is less responsive to medication (Zimmerman et al., 2010b). Another possible explanation for BD overdiagnosis is the secondary gain associated with receiving disability payments (Zimmerman et al., 2010a).Although it is difficult to come to closure on whether a patient with an acute axis I disorder also has a personality disorder, the early identification of personality factors can help guide treatment interventions so that these are more effective. In cases of treatment resistance, this is particularly important: if there is a signifi- cant axis II disorder, refocusing the treatment to address psychosocial stabilization and rehabilitation with supportive use of pharmacologi- cal agents offers a good chance of effective treatment (Bolton and Gunderson, 1996). BD and Major Depression Many patients with BD who have had a preponderance of de- pressive symptoms for many years carry a misdiagnosis of recurrent major depression, leading to treatment with antidepressants that achieve little or no relief of symptoms (Hintz et al., 2010). To confirm CLINICAL CONTROVERSIES The Journal of Nervous and Mental Disease & Volume 201, Number 5, May 2013 www.jonmd.com 435 Department of Neurosciences, Institute of Psychiatry and Psychology, Bipolar Disorders Unit, Universita ` Cattolica del Sacro Cuore, Rome, Italy. Send reprint requests to Marianna Mazza, MD, PhD, Department of Neurosciences, Institute of Psychiatry and Psychology, Bipolar Disorders Unit, Universita Cattolica del Sacro Cuore di Roma, Via Ugo De Carolis, 48 00136 Rome, Italy. E-mail: mariannamazza@hotmail.com; marianna.mazza@rm.unicatt.it. Copyright * 2013 by Lippincott Williams & Wilkins ISSN: 0022-3018/13/20105Y0435 DOI: 10.1097/NMD.0b013e3182901de0 Copyright © 2013 Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.