Understanding the Difference Between Bipolar and Borderline Personality Disorder

What is bipolar disorder vs. borderline personality disorder? Both diagnoses have been in the headlines, but many may wonder: What’s the difference?

Changing moods can often be a natural response to stressful situations. But for some, mood shifts are so significant that they could be a sign of these psychiatric conditions, both of which can include notable changes in mood, according to Dr. Colleen Cullen, a psychologist at NewYork-Presbyterian/Columbia University Irving Medical Center.

“This partial similarity in mood shifts causes many people to confuse the two disorders,” says Dr. Cullen. “Yet they are two distinct psychiatric diagnoses with different symptoms that require different methods of treatment.”

While often misunderstood, these conditions affect millions of Americans. Bipolar disorder is estimated to affect about 2.8% of U.S. adults, while borderline personality disorder is estimated to affect 1.4 to 5.9% of U.S. adults.

How do you know if you or someone you love suffers from one of these disorders? And how can you tell the difference? Health Matters spoke with Dr. Cullen to define these disorders, explain the telltale signs and the recommended treatments.

What does borderline personality disorder look like?

We often think about borderine personality disorder (BPD) as involving dysregulation in five key areas: emotional, behavioral, cognitive (thinking) and interpersonal (e.g., in relationships) as well as dysregulation of self. 

With respect to emotions, individuals with BPD often have intense emotions that can shift rapidly. This can include quickly moving from stable and centered feelings to a negative, depressed state and/or feeling irritable, angry and/or anxious. In this psychiatric illness, the mood shifts often are precipitated by reactions to events that may be disproportionate to the event and for which someone else might have a minimal reaction. In addition, individuals with BPD may take more time returning to their emotional baseline as compared to others. Mood shifts also generally last at least a few hours and don’t typically last more than a few days.

For example, if a friend cancels plans, many of us might be understandably annoyed by this and experience mild irritation that lasts for a short period of time.  Someone who struggles with emotional reactivity may become extremely angry about such an event, and that emotional state could last for hours or days.

Behavioral dysregulation can include impulsive behaviors, for example reckless driving or spending. In addition, individuals may engage in suicidal and/or self-harm behaviors.  All of these behaviors are often considered maladaptive attempts at coping with stressors. 

People with this condition may often engage in “black and white thinking” and have difficulty putting things in perspective. They also may struggle with maintaining a clear sense of their own identity, chronic feelings of emptiness and/or challenges in awareness of their own thoughts, feelings and urges, or what is called dysregulation of self. 

Finally, people with this condition may experience interpersonal dysregulation, which can lead to unstable relationships, significant interpersonal conflicts and fear of abandonment by others; they may take great pains to avoid this abandonment. At times, individuals with borderline personality disorder may also move between idealizing someone, or putting them on a metaphoric pedestal, and then, in response to stressors, devaluing that same person and feeling quite negatively about them. In addition, in some situations individuals may experience difficulty getting their needs met in an effective manner and have trouble saying no skillfully and/or maintaining self-respect in interactions with others.

In discussing disorders that involve changes in mood, it is important to make clear that not all negative emotional states indicate a psychiatric condition. If a marriage ends, or you lose a parent, it’s normal to feel extremely sad and the emotions experienced are appropriate to the circumstances.

How does borderline personality disorder affect relationships?

People with borderline personality disorder have relationships that can be chaotic and intense, at times veering between a desperate neediness for others to an intense anger or dismissal of others when feeling rejected, even in situations where the other person may in fact be neutral or even positive. Individuals with borderline personality disorder can have difficulty accurately reading people’s emotions and trusting others. There can be difficulties with how the individual perceives others.

What is the cause of borderline personality disorder?

There is no single cause of borderline personality disorder, though studies suggest that certain traits, especially a temperament characterized by intense emotional reactions, stem to a large degree from genetics and neurobiological factors.

Developmental and environmental factors, including problems with emotional attunement between a developing child and caregivers, seem to play a role, as do physical or sexual abuse, or emotional neglect. Frequent or significant invalidation, in which individuals are told that how they are feeling or acting is wrong or problematic can also be a factor. However, it’s important to note that in cases with a history of trauma, the disorder seems to stem from a combination of temperament and trauma rather than trauma alone, since many people who have experienced trauma early in life do not go on to develop serious psychiatric illnesses.

How is borderline personality disorder treated?

There is no medication that successfully treats the condition, although they may help reduce some There is no medication that successfully treats the condition, although they may help reduce some specific symptoms, such as intense anxiety or symptoms of depression. Evidence-based models of psychotherapy are the treatment of choice.

• Dialectical behavioral therapy teaches people skills to better regulate their emotions and tolerate intense emotions, improve their interpersonal relationships and increase their mindful awareness of themselves and the world around them, as well as how to apply these skills in everyday situations.
• Transference-focused psychotherapy focuses on a patient’s feelings and behavior, specifically within the relationship between the patient and the therapist. By observing and interpreting distorted or unrecognized emotional states that arise, the therapist is able to help the patient gain emotional balance and a more coherent sense of self.
• Mentalization-based therapy helps individuals differentiate their emotional state from that of others, as well as how their emotional state affects their own behavior. Patients should be better able to process their own emotions, as well as understand the source of other people’s feelings and behaviors.

Good psychiatric management is based on a case management model that combines a focus on the environment of the patient, psychoeducation, supportive therapy, and possibly family therapy.

What is bipolar disorder?

Like borderline personality disorder, those with bipolar disorder experience extreme shifts in mood. In bipolar disorder, individuals meet full criteria for a diagnosis of depression and also have experienced manic symptoms. As compared to borderline personality disorder, these mood states are often more prolonged. Individuals will likely experience symptoms of depression such as sadness, changes in appetite, fatigue, feelings of worthlessness for weeks or months at a time.

They may also have separate, discrete episodes of mania lasting days or weeks. During these times they might speak at a rapidly accelerated pace, demonstrate a decreased need for sleep and yet still have significant energy and stamina, have racing thoughts or an inflated sense of self-esteem and their own worth that is not consistent with reality. They often engage in impulsive behaviors that they would not demonstrate if not in a manic state and that often have significant consequences, such as spending sprees or quitting their job impulsively.

In between the depressed and manic states, they may have periods of stable mood. In another variant of the disorder, some individuals experience repeated depressive states without full-blown manic states; this is referred to as Bipolar II.

What is the cause of bipolar disorder?

Bipolar disorder is rooted in brain chemistry, structural brain differences, and brain functioning, as well as genetics and family history.

How is bipolar disorder treated?

Bipolar disorder can be treated with medications that help stabilize mood. Psychotherapy is usually helpful as well to aid the person in managing complications in their life that stem from the episodes of illness, and to monitor adherence to the medication regimen.

What are the key differences between the disorders?

Bipolar disorder is much more episodic than borderline personality disorder. Individuals with bipolar disorder will have discrete episodes of depression and mania and in between mood episodes, they often demonstrate stability and typical mood states and emotional functioning.  For individuals with borderline personality disorder, they experience chronic difficulties with emotion regulation.

The mood shifts of bipolar disorder are more random and less related to events than those of individuals with borderline personality disorder. In addition, those with bipolar disorder may be more emotionally reactive during a mood episode whereas individuals with borderline personality disorder are generally quite emotionally reactive much of the time.

Bipolar disorder is also more rooted in the biology of the nervous system and more responsive to medication. Borderline personality disorder strongly involves the psychological level of the mind – the way meaning is generated and events are interpreted – in addition to the biology of the brain and nervous system.

What is important for people to know?

Each is a serious illness, and those suffering benefit from seeking out the proper treatment. Both illnesses can be successfully treated. It is essential to establish an accurate diagnosis as different psychiatric illnesses, including borderline personality disorder and bipolar disorder, respond to different treatments. It is extremely beneficial for patients with borderline personality disorder to see a specialist with experience in treating this illness. .

Learn more about psychiatry and mental health services at NewYork-Presbyterian.