Introduction 

Personality disorders are conditions that can cause a range of distressing symptoms and patterns of abnormal behaviour.

This could include:

• overwhelming feelings of distress, anxiety, worthlessness or anger
• difficulty managing such feelings without self-harming – for example, by abusing drugs and alcohol or taking overdoses
• difficulty maintaining stable and close relationships
• sometimes having periods of loss of contact with reality
• in some cases, threats of harm to others

Read more about the symptoms of borderline personality disorder.

Personality disorders typically emerge in adolescence and persist into adulthood. They may be associated with genetic and family factors, and experiences of distress or fear during childhood, such as neglect or abuse, are common. Personality disorders range from mild to severe.

What is borderline personality disorder (BPD)?

It used to be thought that people with BPD were at the "border" between:

• neurosis – where a person is mentally distressed, but can still tell the difference between their perception and reality
• psychosis – where a person is unable to tell the difference between their perception and reality, and may experience delusions and hallucinations

Now it's known that this is not an accurate description. BPD is best understood as a disorder of mood and how a person interacts with others.

BPD is a common personality disorder seen by healthcare professionals. Although BPD is said to be more common in women, this is probably because it is recognised less frequently in men, who may be less likely to seek treatment.

Read more about how BPD is diagnosed.

How does BPD develop?

The causes of BPD are unclear. However, as with most conditions, BPD appears to be due to a combination of genetic and environmental factors.

Traumatic events that occur during childhood are associated with developing BPD. An estimated 8 out of 10 people with BPD experience parental neglect or physical, sexual or emotional abuse during their childhood.

Read more about the causes of BPD.

Outlook

BPD can be a serious condition, and many people with the condition self-harm and attempt suicide. It is estimated that 60-70% of people with BPD will attempt suicide at some point in their life.

However, for many with BPD, the outlook is reasonably good over time, and psychological or medical treatment may help.

Treatment may involve a range of individual and group psychological therapies (psychotherapy) carried out by trained professionals working with a community mental health team. Effective treatment may last more than a year.

Read more about treatments for BPD.

Recent studies have suggested that the majority of those with BPD do well over time, with most experiencing sustained relief from symptoms, and around half being completely free of symptoms and able to function well.

Additional treatment is recommended for people whose symptoms return.