Borderline personality disorder is often a devastating mental condition, both for the people who have it and for those around them.

Perhaps shaped by harmful childhood experiences or brain dysfunctions, people diagnosed with borderline personality disorder live in a world of inner and outer turmoil. They have difficulty regulating their emotions and are often in a state of upheaval. They have distorted images of themselves, often feeling worthless and fundamentally bad or damaged.

And while they yearn for loving relationships, people with borderline personality disorder typically find that their anger, impulsivity, stormy attachments and frequent mood swings push others away.

Over the last 10 years, increasing awareness and research are helping improve the treatment and understanding of borderline personality disorder. At the same time, it remains a controversial condition, particularly since so many more women than men are diagnosed with it, raising questions about gender bias. Although definitive data are lacking, it’s estimated that 1 percent to 2 percent of American adults have borderline personality disorder (BPD). It occurs in about one in every 33 women, compared with one in every 100 men, and is usually diagnosed in early adulthood.

Contrary to lingering perceptions, emerging evidence indicates that people with BPD often get better over time and that they can live happy, peaceful lives.

Borderline personality disorder affects how people feel about themselves, how they relate to others and how they behave.

People with BPD often have an unstable sense of who they are. That is, their self-image or sense of self often rapidly changes. They typically view themselves as evil or bad, and sometimes they may feel as if they don’t exist at all. This unstable self-image can lead to frequent changes in jobs, friendships, goals, values and gender identity.

Relationships are usually in turmoil. People with BPD often experience a love-hate relationship with others. They may idealize someone one moment and then abruptly and dramatically shift to fury and hate over perceived slights or even misunderstandings. This is because people with the disorder have difficulty accepting gray areas — things are either black or white. For instance, in the eyes of a person with BPD, someone is either good or evil. And that same person may be good one day and evil the next.

In addition, people with BPD often engage in impulsive and risky behavior. This behavior often winds up hurting them, whether emotionally, financially or physically. For instance, they may drive recklessly, engage in unsafe sex, take illicit drugs or go on spending or gambling sprees. People with BPD also often engage in suicidal behavior or deliberately injure themselves for emotional relief.

Other signs and symptoms of borderline personality disorder may include:

• Strong emotions that wax and wane frequently
• Intense but short episodes of anxiety or depression
• Inappropriate anger, sometimes escalating into physical confrontations
• Difficulty controlling emotions or impulses
• Fear of being alone

As with other mental disorders, the causes of borderline personality disorder are complex. The name arose because of theories in the 1940s and 1950s that the disorder was on the border between neurosis and psychosis. But that view doesn’t reflect current thinking. In fact, some advocacy groups have pressed for changing the name, such as calling it emotional regulation disorder.

Meanwhile, the cause of BPD remains under investigation, and there’s no known way to prevent it. Possible causes include:

• Genetics. Some studies of twins and families suggest that personality disorders may be inherited.
• Environmental factors. Many people with borderline personality disorder have a history of childhood abuse, neglect and separation from caregivers or loved ones.
• Brain abnormalities. Some research shows changes in certain areas of the brain involved in emotion regulation, impulsivity and aggression. In addition, certain brain chemicals that help regulate mood, such as serotonin, may not function properly.

Most likely, a combination of these issues results in borderline personality disorder.

Personality forms during childhood. It’s shaped by both inherited tendencies and environmental factors, or your experiences during childhood. Some factors related to personality development can increase the risk of developing borderline personality disorder. These include:

• Hereditary predisposition. You may be at a higher risk if a close family member — a mother, father or sibling — has the disorder.
• Childhood abuse. Many people with the disorder report being sexually or physically abused during childhood.
• Neglect. Some people with the disorder describe severe deprivation, neglect and abandonment during childhood.

People with borderline personality disorder often feel misunderstood, alone, empty and hopeless. They’re typically full of self-hate and self-disgust. They may be fully aware that their behavior is destructive and be distressed about it. Impulsivity may cause problems with gambling, driving or even the law. You may find that many areas of your life are affected, including relationships, work or school.

If you notice these things about yourself, talk to your doctor or a mental health provider. The right treatment can help you feel better about yourself and help you live a more stable, rewarding life.

If you notice these things in a family member or friend, talk to them about seeing a doctor or mental health provider. But keep in mind that you can’t force someone to seek help. If the relationship has you unduly distressed, you may find it helpful to see a therapist yourself.

Personality disorders are diagnosed based on signs and symptoms and a thorough psychological evaluation. To be diagnosed with borderline personality disorder, someone must meet criteria spelled out in the Diagnostic and Statistical Manual of Mental Disorders (DSM). This manual is published by the American Psychiatric Association and is used by mental health professionals to diagnose mental conditions and by insurance companies to reimburse for treatment.

The DSM criteria note that people with BPD have a pattern of unstable relationships, self-image and mood, as well as impulsive behavior. These typically begin in early adulthood.

For BPD to be diagnosed, at least five of the following signs and symptoms must be present:

• Intense fears of abandonment
• A pattern of unstable relationships
• Unstable self-image
• Impulsive and self-destructive behaviors
• Suicidal behavior or self-injury
• Wide mood swings
• Chronic feelings of emptiness
• Inappropriate anger
• Periods of paranoia and loss of contact with reality

A diagnosis of BPD is usually made in adults, not children or adolescents. That’s because what appear to be signs and symptoms of BPD may go away with maturity.

Borderline personality disorder can damage many areas of a person’s life. Relationships, jobs, school, social activities, self-image — all can be negatively affected. Repeated job losses and broken marriages are common. Self-injury, such as cutting or burning, can result in scarring and frequent hospitalizations. Suicide rates among people with BPD are very high, reaching 10 percent.

In addition, people with borderline personality disorder may have other mental health problems, too, including:

• Depression
• Substance abuse
• Anxiety disorders
• Eating disorders
• Bipolar disorder
• Other personality disorders

Because of their risky, impulsive behavior, people with BPD are also more vulnerable to unplanned pregnancies, sexually transmitted diseases, motor vehicle accidents and physical fights. They may also be involved in abusive relationships, either as the abuser or the abused.

Treatment for borderline personality disorder has improved in recent years with the adoption of techniques specifically aimed at people with this disorder. Treatment includes:

• Psychotherapy. This is the core treatment for BPD. Dialectical behavior therapy (DBT) was designed specifically to treat the disorder. Generally conducted through individual, group and phone counseling, DBT uses a skills-based approach to teach people how to regulate their emotions, tolerate distress and improve relationships.
• Medications. Medications can’t cure BPD, but they can help associated problems, such as depression, impulsivity and anxiety. Medications may include antidepressant, antipsychotic and antianxiety medications.
• Hospitalization. At times, people with BPD may need more intense treatment in a psychiatric hospital or clinic. Hospitalization can also keep them safe from self-injury.

Because treatment can be intense and long term, people face the best chance for success when they find mental health providers with experience treating BPD.

Living with borderline personality disorder can be difficult. You may fully realize that your behaviors and thoughts are self-destructive or damaging yet feel unable to control them. Treatment can help you learn skills to manage and cope with your condition.

Other things you can do to help manage your condition and feel better about yourself include:

• Sticking to your treatment plan
• Attending therapy sessions as scheduled
• Practicing healthy ways to ease painful emotions, rather than inflicting self-injury
• Not blaming yourself for having the disorder but recognizing your responsibility to get it treated
• Learning what things may trigger angry outbursts or impulsive behavior
• Not being embarrassed by having this condition
• Getting treatment for related problems, such as substance abuse
• Educating yourself about the disorder so you understand its causes and treatments better
• Reaching out to others with the disorder to share insights and experiences

Remember, there’s no one right path to recovery from BPD. The condition seems to be worse in young adulthood and may gradually get better with age. Many people with the disorder find greater stability in their lives during their 30s and 40s. Their inner misery may lessen and they go on to sustain loving relationships and enjoy meaningful careers.