A common diagnostic dilemma among clinicians is differentiating between Borderline Personality Disorder (BPD) and Bipolar II Disorder (BP II) (Bayes et al., 2014). These two disorders share similar features including impulsivity and emotional dysregulation. Additionally, “affect storms” in individuals with BPD can resemble hypomanic episodes similar to ones seen in individuals with BP II. Bayes et al., discuss various distinctions between the two disorders to assist clinicians with differentiating between the two (2014).
Family history, age of onset, and illness course
The first three categories examined are family history, age of onset, and illness course. Individuals with BP II have a greater probability of having a first-degree relative with bipolar disorder or another mood disorder (Bayes et al., 2014). Individuals with BPD have an increased likelihood of having a family member with an impulse control disorder, such as antisocial or substance use disorder, or a unipolar mood condition. Symptoms of BP II usually appear in late adolescence or young adulthood and the onset represents a distinct change in the individual. There is no distinct onset period for BPD and many individuals with BPD report being depressed their whole lives. BP II tends not to remit with age and can worsen over time, whereas BPD has a more favorable prognosis, with many individuals no longer meeting criteria in middle age (Bayes et al., 2014).
Depressive Symptoms and Suicidality
Depressive symptoms among individuals with BP II are usually presented as melancholic features, agitation, and mixed symptoms of depression (Bayes et al., 2014). They experience “typical” depressive feature such as decreased self-esteem and self-criticism, and feel guilty about annoying others with irritable mood and are self-accusatory. Individuals with BPD has depressive symptoms represented by non-melancholic reactive depressive episodes. They are characterized by emptiness, shame, and “painful incoherence.” They also tend to project responsibility onto others, being accusatory, blaming, hostile, and more angry than depressed. Suicidality and self-harm occur in both BP II and BPD with similar frequencies (Bayes et al., 2014).
Hypomanic Symptoms, Impulsivity, and Mood State Context
Individuals with BP II usually report elated mood, increased energy, creativity, connectedness, grandiosity, and productivity (Bayes et al., 2014). These traits are viewed as uncharacteristic and only occur during a mood episode. There is usually also a reduction in anxiety symptoms when an individual with BP II is experiencing a hypomanic episode. Individuals with BPD report emotional dysregulation and elation is rarely present. There remains an ongoing poor self-image and increased anxiety symptoms during these periods. Episodes of impulsivity are more commonly associated with hypomanic mood states in individuals with BP II, where as impulsivity is a core diagnostic feature for an individual with BPD and tends to be more enduring. Individuals with BP II are more likely than those with BPD to have autonomous mood episodes and lacking an interpersonal context. Individuals with BPD are usually more reactive, generally triggered by a psychologically salient interpersonal event (Bayes et al., 2014).
Psychosis and Trauma
During depressive episodes, psychotic features are uncommon for individuals with BP II (Bayes et al., 2014). There is a lifetime prevalence ranging from 3 to 45% and when present they tend to be mood congruent. 75% of individuals with BPD will experience transient dissociative and paranoid symptoms, but rarely have a depressive theme. A history of childhood trauma is not a distinctly differentiating feature, as there are high rates associated with both disorders. 50% of individuals with BP II report experience childhood trauma and 60 to 80% among individuals with BPD (Bayes et al., 2014).
Self-Identity and Relationships
Individuals with BP II tend to experience self-deficits only when depressed and a grandiose self when hypomanic (Bayes et al., 2014). There is typically stability while euthymic and they are able to maintain stable relationships. Individuals with BPD generally experience a disruption to their sense of self and core elements of BPD include “painful incoherence” and “role absorption.” There is a tendency towards idealization and devaluations, as well as, fears of abandonment and ongoing interpersonal conflicts (Bayes et al., 2014).
Therapy including cognitive behavioral therapy (CBT) and dialectical behavior therapy (DBT) have shown to be effective for individuals with BP II (Bayes et al., 2014). Additionally, antidepressants, anticonvulsant mood stabilizers, and atypical antipsychotics are usually prescribed to treat symptoms of BP II. Symptoms of BPD rarely remit with the use of mood stabilizers. DBT is typically used with individuals with BPD, to work on disrupted sense of self and improving mutually satisfying relationships (Bayes et al., 2014).
Bayes, A., Parker, G., & Fletcher, K. (2014). Clinical differentiation of bipolar II disorder from borderline personality disorder. Current opinion in psychiatry, 27(1), 14-20.
James Bender, MA
WKPIC Doctoral Intern