Borderline Personality Disorder (Part I)

Borderline personality disorder (BPD), also known as emotionally unstable personality disorder (EUPD), is a mental illness characterized by a long-term pattern of unstable relationships, strong emotional reactions, and distorted sense of self.  There is often self-harm and other dangerous behavior.  People may also struggle with a feeling of emptiness, fear of abandonment, and feeling cut off from reality.  Symptoms may be brought on by seemingly normal events.  The behavior typically begins by early adulthood and occurs across a variety of situations.  Substance abuse, depression, and eating disorders are commonly associated with BPD.  Up to 10% of people affected die by suicide.

BPD's causes are unclear but seem to involve genetic, neurological, environmental, and social factors.  It occurs about five times more often in a person who has an affected close relative.  Adverse life events also appear to play a role.  The underlying mechanism appears to involve the frontolimbic network of neurons.  BPD is recognized by the Diagnostic and Statistical Manual of Mental Disorders (DSM) as a personality disorder, along with nine other such disorders.  Diagnosis is based on the symptoms, while a medical examination may be done to rule out other problems.  The condition must be differentiated from an identity problem or substance use disorders, among other possibilities.

BPD is typically treated with therapy, such as cognitive behavior therapy (CBT).  Another type, dialectical behavior therapy (DBT), may reduce the risk of suicide.  Therapy may occur one-on-one or in a group.  While medications do not cure BPD, they may be used to help with the associated symptoms.  Some people require care in hospital.

About 1.6% of people have BPD in a given year.  Women are diagnosed about three times as often as men.  It appears to become less common among older people.  Up to half of people improve over a ten-year period.  People affected typically use a high amount of healthcare resources.  There is an ongoing debate about the naming of the disorder, especially the suitability of the word borderline.  The disorder is often stigmatized in both the media and the psychiatric field. 

Signs and symptoms

BPD is characterized by the following signs and symptoms:

• Markedly disturbed sense of reality
• Frantic efforts to avoid real or imagined abandonment and extreme reactions
• Splitting ("black-and-white" thinking)
• Impulsive or dangerous behaviors (e.g., spending, sex, substance abuse, reckless driving, binge eating)
• Intense or uncontrollable emotional reactions that often seem disproportionate to the event or situation
• Unstable and chaotic interpersonal relationships
• Self-damaging behavior
• Distorted self-image
• Dissociation
• Frequently accompanied by depression, anxiety, anger, substance abuse, and rage

 

Emotions

People with BPD may feel emotions with greater ease, depth and for a longer time than others do.  A core characteristic of BPD is affective instability, which generally manifests as unusually intense emotional responses to environmental triggers, with a slower return to a baseline emotional state.  According to Marsha Linehan, the sensitivity, intensity, and duration with which people with BPD feel emotions have both positive and negative effects.  People with BPD are often exceptionally enthusiastic, idealistic, joyful, and loving.  However, they may feel overwhelmed by negative emotions ("anxiety, depression, guilt/shame, worry, anger, etc."), experiencing intense grief instead of sadness, shame and humiliation instead of mild embarrassment, rage instead of annoyance, and panic instead of nervousness.

People with BPD are also especially sensitive to feelings of rejection, criticism, isolation, and perceived failure.  Before learning other coping mechanisms, their efforts to manage or escape from their very negative emotions may lead to emotional isolation, self-injury or suicidal behavior.  They are often aware of the intensity of their negative emotional reactions and, since they cannot regulate them, shut them down entirely since awareness would only cause further distress.  This can be harmful to people with BPD, since in normal functioning negative emotions alert people to the presence of a problematic situation and move them to address it.

While people with BPD feel euphoria (ephemeral or occasional intense joy), they are especially prone to dysphoria (a profound state of unease or dissatisfaction), depression, and/or feelings of mental and emotional distress. Zanarini et al. recognized four categories of dysphoria that are typical of this condition: extreme emotions, destructiveness or self-destructiveness, feeling fragmented or lacking identity, and feelings of victimization.  Within these categories, a BPD diagnosis is strongly associated with a combination of three specific states: feeling betrayed, feeling out of control, and "feeling like hurting myself".  Since there is great variety in the types of dysphoria experienced by people with BPD, the amplitude of the distress is a helpful indicator of borderline personality disorder.

In addition to intense emotions, people with BPD experience emotional "lability" (changeability, or fluctuation). Although that term suggests rapid changes between depression and elation, the mood swings in people with this condition more frequently involve anxiety, with mood fluctuating between anger and anxiety and between depression and anxiety.

Interpersonal relationships

People with BPD can be very sensitive to the way others treat them, by feeling intense joy and gratitude at perceived expressions of kindness, and intense sadness or anger at perceived criticism or hurtfulness.  People with BPD often engage in idealization and devaluation of others, alternating between high positive regard for people and great disappointment in them.  Their feelings about others often shift from admiration or love to anger or dislike after a disappointment, a threat of losing someone, or a perceived loss of esteem in the eyes of someone they value. This phenomenon is sometimes called splitting.  Combined with mood disturbances, idealization and devaluation can undermine relationships with family, friends, and co-workers.

While strongly desiring intimacy, people with BPD tend toward insecure, avoidant or ambivalent or fearfully preoccupied attachment fixtures in relationships, and they often view the world as dangerous and malevolent.  BPD, like other personality disorders, is linked to increased levels of chronic stress and conflict in romantic relationships, decreased satisfaction on the part of romantic partners, abuse, and unwanted pregnancy.

Behavior

Impulsive behavior is common, including substance or alcohol abuse, eating disorders, unprotected sex or indiscriminate sex with multiple partners, reckless spending, and reckless driving.  Impulsive behavior may also include leaving jobs or relationships, running away, and self-injury.  People with BPD might do this because it gives them the feeling of immediate relief from their emotional pain.  However, in the long term, people with BPD have increased shame and guilt that follow such actions and the inevitable consequences of continuing this behaviour over a prolonged period of time.  A cycle often begins in which people with BPD feel emotional pain, engage in impulsive behavior to relieve that pain, feel shame and guilt over their actions, feel emotional pain from the shame and guilt, and then experience stronger urges to engage in impulsive behavior to relieve the new pain.  As time goes on, impulsive behavior may become an automatic response to emotional pain. 

Self-harm and suicide

Self-harming or suicidal behavior is one of the core diagnostic criteria in the DSM-5.  Self-harm occurs in 50 to 80% of people with BPD. The most frequent method of self-harm is cutting.  Bruising, burning, head banging or biting are not uncommon with BPD.  People with BPD may feel emotional relief after cutting themselves.

The lifetime risk of suicide among people with BPD is between 3% and 10%.   There is evidence that men diagnosed with BPD are approximately twice as likely to die by suicide as women diagnosed with BPD.  There is also evidence that a considerable percentage of men who die by suicide may have undiagnosed BPD.

The reported reasons for self-harm differ from the reasons for suicide attempts.  Nearly 70% of people with BPD self-harm without trying to end their life.  Reasons for self-harm include expressing anger, self-punishment, generating normal feelings (often in response to dissociation), and distracting oneself from emotional pain or difficult circumstances.  In contrast, suicide attempts typically reflect a belief that others will be better off following the suicide.  Both suicide and self-harm are a response to feeling negative emotions.  Sexual abuse can be a particular trigger for suicidal behavior in adolescents with BPD tendencies. 

Sense of self

People with BPD tend to have trouble seeing a clear picture of their identity. In particular, they tend to have difficulty knowing what they value, believe, prefer, and enjoy.  They are often unsure about their long-term goals for relationships and jobs. This difficulty with knowing who they are and what they value can cause people with BPD to experience feeling "empty" and "lost".  Self-image can also change rapidly from healthy to unhealthy. 

Cognitions

The often intense emotions experienced by people with BPD can make it difficult for them to control the focus of their attention – to concentrate.  In addition, people with BPD may tend to dissociate, which can be thought of as an intense form of "zoning out".  It is sometimes possible for another person to tell when someone with BPD is dissociating, because their facial or vocal expressions may become flat or expressionless, or they may appear to be distracted; at other times, dissociation may be barely noticeable.

Dissociation often occurs in response to experiencing a painful event (or experiencing something that triggers the memory of a painful event). It involves the mind automatically redirecting attention away from that event—presumably to protect against experiencing intense emotion and unwanted behavioral impulses that such emotion might otherwise trigger.  Although the mind's habit of blocking out intense painful emotions may provide temporary relief, it can also have the unwanted side effect of blocking or blunting the experience of ordinary emotions, reducing the access of people with BPD to the information contained in those emotions: information which helps guide effective decision-making in daily life. 

Disability

Many people with BPD are able to work if they find appropriate jobs and their condition is not too severe. People with BPD may be found to have a disability in the workplace if the condition is severe enough that the behaviors of sabotaging relationships, engaging in risky behaviors or intense anger prevent the person from functioning in their job role.

Causes

As is the case with other mental disorders, the causes of BPD are complex and not fully agreed upon.  Evidence suggests that BPD and post-traumatic stress disorder (PTSD) may be related in some way.  Most researchers agree that a history of childhood trauma can be a contributing factor, but less attention has historically been paid to investigating the causal roles played by congenital brain abnormalities, genetics, neurobiological factors, and environmental factors other than trauma.

Social factors include how people interact in their early development with their family, friends, and other children.  Psychological factors include the individual's personality and temperament, shaped by their environment and learned coping skills that deal with stress.  These different factors together suggest that there are multiple factors that may contribute to the disorder. 

Genetics

The heritability of BPD has been estimated at 40%. That is, 40 percent of the variability in liability underlying BPD in the population can be explained by genetic studies.  Twin studies may overestimate the effect of genes on variability in personality disorders due to the complicating factor of a shared family environment.  Nonetheless, the researchers of this study concluded that personality disorders "seem to be more strongly influenced by genetic effects than almost any axis I disorder [e.g., bipolar disorder, depression, eating disorders], and more than most broad personality dimensions."  Moreover, the study found that BPD was estimated to be the third most-heritable personality disorder out of the 10 personality disorders reviewed.  Twin, sibling, and other family studies indicate partial heritability for impulsive aggression, but studies of serotonin-related genes have suggested only modest contributions to behavior.

Families with twins in the Netherlands were participants of an ongoing study by Trull and colleagues, in which 711 pairs of siblings and 561 parents were examined to identify the location of genetic traits that influenced the development of BPD.  Research collaborators found that genetic material on chromosome 9 was linked to BPD features.  The researchers concluded that "genetic factors play a major role in individual differences of borderline personality disorder features."  These same researchers had earlier concluded in a previous study that 42 percent of variation in BPD features was attributable to genetic influences and 58 percent was attributable to environmental influences.  Genes under investigation as of 2012 include the 7-repeat polymorphism of the dopamine D4 receptor (D4R4) on chromosome 11, which has been linked to disorganized attachment, whilst the combined effect of the 7-repeat polymorphism and the 10/10 dopamine transporter (DAT) genotype has been linked to abnormalities in inhibitory control, both noted features of BPD.  There is a possible connection to chromosome 5.

Brain abnormalities

A number of neuroimaging studies in BPD have reported findings of reductions in regions of the brain involved in the regulation of stress responses and emotion, affecting the hippocampus, the orbitofrontal cortex, and the amygdala, amongst other areas.  A smaller number of studies have used magnetic resonance spectroscopy to explore changes in the concentrations of neurometabolites in certain brain regions of BPD patients, looking specifically at neurometabolites such as N-acetylaspartate, creatine, glutamate-related compounds, and choline-containing compounds. 

Hippocampus

The hippocampus tends to be smaller in people with BPD, as it is in people with post-traumatic stress disorder (PTSD). However, in BPD, unlike PTSD, the amygdala also tends to be smaller. 

Amygdala

The amygdalae are smaller and more active in people with BPD.  Decreased amygdala volume has also been found in people with obsessive-compulsive disorder (OCD).  One study has found unusually strong activity in the left amygdalas of people with BPD when they experience and view displays of negative emotions.  This unusually strong activity may explain the unusual strength and longevity of fear, sadness, anger, and shame experienced by people with BPD, as well as their heightened sensitivity to displays of these emotions in others. 

Prefrontal cortex

The prefrontal cortex tends to be less active in people with BPD, especially when recalling memories of abandonment.  This relative inactivity occurs in the right anterior cingulate.

Given its role in regulating emotional arousal, the relative inactivity of the prefrontal cortex might explain the difficulties people with BPD experience in regulating their emotions and responses to stress. 

Hypothalamic-pituitary-adrenal axis

The hypothalamic-pituitary-adrenal axis (HPA axis) regulates cortisol production, which is released in response to stress. Cortisol production tends to be elevated in people with BPD, indicating a hyperactive HPA axis in these individuals.  This causes them to experience a greater biological stress response, which might explain their greater vulnerability to irritability.  Since traumatic events can increase cortisol production and HPA axis activity, one possibility is that the prevalence of higher than average activity in the HPA axis of people with BPD may simply be a reflection of the higher than average prevalence of traumatic childhood and maturational events among people with BPD.  Another possibility is that, by heightening their sensitivity to stressful events, increased cortisol production may predispose those with BPD to experience stressful childhood and maturational events as traumatic.

Increased cortisol production is also associated with an increased risk of suicidal behavior. 

Neurobiological factors

Estrogen

Individual differences in women's estrogen cycles may be related to the expression of BPD symptoms in female patients.  A 2003 study found that women's BPD symptoms were predicted by changes in estrogen levels throughout their menstrual cycles, an effect that remained significant when the results were controlled for a general increase in negative affect.

Developmental factors

Childhood trauma

There is a strong correlation between child abuse, especially child sexual abuse, and development of BPD.  Many individuals with BPD report a history of abuse and neglect as young children, but causation is still debated.  Patients with BPD have been found to be significantly more likely to report having been verbally, emotionally, physically, or sexually abused by caregivers of either gender.  They also report a high incidence of incest and loss of caregivers in early childhood.  Individuals with BPD were also likely to report having caregivers of both sexes deny the validity of their thoughts and feelings. Caregivers were also reported to have failed to provide needed protection and to have neglected their child's physical care. Parents of both sexes were typically reported to have withdrawn from the child emotionally and to have treated the child inconsistently.  Additionally, women with BPD who reported a previous history of neglect by a female caregiver and abuse by a male caregiver were significantly more likely to have experienced sexual abuse by a non-caregiver.

It has been suggested that children who experience chronic early maltreatment and attachment difficulties may go on to develop borderline personality disorder.  Writing in the psychoanalytic tradition, Otto Kernberg argues that a child's failure to achieve the developmental task of psychic clarification of self and other and failure to overcome splitting might increase the risk of developing a borderline personality. 

Neurological patterns

The intensity and reactivity of a person's negative affectivity, or tendency to feel negative emotions, predicts BPD symptoms more strongly than does childhood sexual abuse.  This finding, differences in brain structure, and the fact that some patients with BPD do not report a traumatic history, suggest that BPD is distinct from the post-traumatic stress disorder which frequently accompanies it. Thus, researchers examine developmental causes in addition to childhood trauma.

Research published in January 2013 by Anthony Ruocco at the University of Toronto has highlighted two patterns of brain activity that may underlie the dysregulation of emotion indicated in this disorder: (1) increased activity in the brain circuits responsible for the experience of heightened emotional pain, coupled with (2) reduced activation of the brain circuits that normally regulate or suppress these generated painful emotions. These two neural networks are seen to be dysfunctionally operative in the frontolimbic regions, but the specific regions vary widely in individuals, which calls for the analysis of more neuroimaging studies.

Also (contrary to the results of earlier studies) sufferers of BPD showed less activation in the amygdala in situations of increased negative emotionality than the control group. John Krystal, editor of the journal Biological Psychiatry, wrote that these results "[added] to the impression that people with borderline personality disorder are 'set-up' by their brains to have stormy emotional lives, although not necessarily unhappy or unproductive lives". Their emotional instability has been found to correlate with differences in several brain regions. 

Mediating and moderating factors

Executive function

While high rejection sensitivity is associated with stronger symptoms of borderline personality disorder, executive rejection appears to mediate the relationship between rejection sensitivity and BPD symptoms.  That is, a group of cognitive processes that include planning, working memory, attention, and problem-solving might be the mechanism through which rejection sensitivity impacts BPD symptoms. A 2008 study found that the relationship between a person's rejection sensitivity and BPD symptoms was stronger when executive function was lower and that the relationship was weaker when executive function was higher.  This suggests that high executive function might help protect people with high rejection sensitivity against symptoms of BPD.  A 2012 study found that problems in working memory might contribute to greater impulsivity in people with BPD. 

Family environment

Family environment mediates the effect of child sexual abuse on the development of BPD. An unstable family environment predicts the development of the disorder, while a stable family environment predicts a lower risk. One possible explanation is that a stable environment buffers against its development. 

Self-complexity

Self-complexity, or considering one's self to have many different characteristics, may lessen the apparent discrepancy between an actual self and a desired self-image. Higher self-complexity may lead a person to desire more characteristics instead of better characteristics; if there is any belief that characteristics should have been acquired, these may be more likely to have been experienced as examples rather than considered as abstract qualities. The concept of a norm does not necessarily involve the description of the attributes that represent the norm: cognition of the norm may only involve the understanding of "being like", a concrete relation and not an attribute. 

Thought suppression

A 2005 study found that thought suppression, or conscious attempts to avoid thinking certain thoughts, mediates the relationship between emotional vulnerability and BPD symptoms.  A later study found that the relationship between emotional vulnerability and BPD symptoms is not necessarily mediated by thought suppression. However, this study did find that thought suppression mediates the relationship between an invalidating environment and BPD symptoms.