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From the Research
Differences between Bipolar Disorder (BD) and Borderline Personality Disorder (BPD)
- BD and BPD are frequently confused due to their symptomatic overlap, but they can be distinguished by their phenomenology, etiology, family history, biological studies, outcome, and response to medication 1
- Affective instability is a prominent feature of both disorders, but the pattern is entirely different: BPD is characterized by transient mood shifts in response to interpersonal stressors, whereas BD is associated with sustained mood changes 1
- The manifestation of emotional dysregulation and impulsivity in BD and BPD is different, and these symptoms are driven by distinct aetiological factors 2
- Childhood trauma is a possible differentiating variable between BD and BPD, as it shapes the circumstances in which emotional dysregulation and impulsivity are triggered, and modulates the clinical expression and course of bipolar illness 2
Clinical Factors for Differential Diagnosis
- A clinical analysis of identity, self-concept, and self-esteem may help distinguish BD and BPD, with qualitative differences between the two disorders 3
- In BPD, there is a well-documented identity diffusion, and the self-concept appears predominantly negative, with shifts in self-concept and self-esteem often tied to interpersonal triggers 3
- In BD, patients struggle with their identity, but narrative identity might be less compromised compared with BPD, with shifts in self-concept and self-esteem more linked to internal factors such as mood and motivation 3
Neuroanatomical and Neurobiological Differences
- BD and BPD demonstrate similarities in neuroanatomy, such as alterations in the limbic system, as well as specific differences, such as the increase in size of the amygdala in BD and the decrease in BPD 4
- Both disorders appear to have a significant percentage of heritability, but environmental factors seem to hold an important role in BPD, in particular 4
- Alterations in the dopaminergic and serotonergic system are present in both BD and BPD 4
Treatment and Prognosis
- Medication treatment differs between BD and BPD, with antidepressants considered effective in BPD, and mood stabilizers the main treatment of choice in BD 4
- Functionality and prognosis are slightly worse for BPD 4
- The effectiveness of psychotherapeutic methods is still under research for both disorders 4