Borderline personality disorder



  1. What is borderline personality disorder?
  2. What are the symptoms?
  3. What causes borderline personality disorder?
  4. How is borderline personality disorder diagnosed?
  5. What is the treatment?
  6. What are the UK statistics for borderline personality disorder?
  7. Is borderline personality disorder genetic?
  8. Is borderline personality disorder different to bipolar disorder?
  9. Can people outgrow borderline personality disorder?


What is borderline personality disorder?

Borderline personality disorder (BPD) is a mental health disorder that affects the way someone thinks, feels and relates to others which can create problems in everyday life. BPD is thought to be the most common of personality disorders.


Man in bathroom looking into mirror with a serious expression


What are the symptoms?

The symptoms of borderline personality disorder generally start to show and emerge in adolescence and continue into adulthood.

Signs and symptoms of BPD are categorised into four main areas:

  • Impulsive behaviour
  • Emotional instability – this is known in psychiatry as affective dysregulation.
  • Intense, unstable relationships with others.
  • Cognitive or perceptual distortions – this describes warped, disturbed patterns of thinking or perception.



What causes borderline personality disorder?

As with many mental health disorders, the exact causes of BPD are not clear cut, however, BPD is thought to result from a combination of environmental and genetic factors.


Brain abnormalities:

  • Some research has indicated that parts of the brain involved in the regulation of emotion, aggression and impulsivity show changes in those suffering from BPD.

Environmental factors thought to be common among those with BPD:

  • Having a stressful childhood.
  • Being neglected by one or both parents as a child.
  • Being a victim of sexual, emotional or physical abuse.
  • Being exposed to a family member with a serious mental illness or substance abuse problem as a child.


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How is borderline personality disorder diagnosed?

A diagnosis of BPD will be based on the following:

  • Medical history
  • A psychological evaluation, which can sometimes involve a series of questionnaires
  • A thorough interview with a specialist

There is a set of criteria used to diagnose BPD which are internationally recognised, which a specialist will use to guide their diagnosis.



What is the treatment?

Treatment for borderline personality disorder uses psychotherapy, and sometimes medication too. Generally, the purpose of BPD treatment is to show how you can cope with such a disorder and how to live a more stable and rewarding life.


There are lots of different types of psychotherapy, but fundamentally each will take the time to understand how someone with BPD thinks and feels, and to work on how to cope and to help the patient better understand their own condition.

These are the forms of psychotherapy found to be effective when treating borderline personality disorder:

  • Dialectical behaviour therapy (DBT)
  • Mentalisation-based therapy (MBT)
  • Therapeutic communities (TCs)
  • Art therapies


  • The use of medication in treating BPD is disputed.
  • However, if someone presents other mental health conditions as well, such as depression, anxiety disorder or bipolar disorder, then mood stabilisers or antipsychotic medication might be prescribed to help reduce some of the mood swings and psychotic symptoms.


What are the UK statistics for borderline personality disorder?

It’s estimated by NICE (The National Institute for Health and Care Excellence) that prevalence of BPD in the UK varies between 0.7 and 2 per cent in the general population.


The body has also found that BPD is predominantly diagnosed in women, who are more likely to seek treatment. People with BDP also use mental health services at higher rates than people with other mental health conditions, other than those with schizophrenia.


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Is borderline personality disorder genetic?

There may be genes that make you more vulnerable to developing BPD, but there is no evidence there is a gene for it.


There have been identical twin studies have found that if one identical twin had BPD, there was a two in three chance than the other would also have BPD. However, caution should be exercised regarding these results.



Is borderline personality disorder different to bipolar disorder?

There are some similarities between borderline personality disorder and bipolar disorder. However, they are different mental health conditions and have distinctive characteristics.


Both BPD and bipolar disorders are known for mood swings. However, bipolar mood swings are defined by alternating periods of depression and mania that last for days to months, accompanied by changes in sleep, energy, speech and thinking. In BPD, mood swings are triggered by interpersonal conflicts and last for minutes to hours.


People with BPD are more likely to have had some type of trauma as a child than those with bipolar disorder.


Medication is used to treat both BPD and bipolar disorder but it’s less likely for the main focus of BPD treatment to be medicine-based, even though short stays in hospital may be required to manage times of crisis that can involve threats to well-being and safety.



Can people outgrow borderline personality disorder?

While experts have found that BPD symptoms seem to decline in frequency and severity with age, some have suggested that reasons for this may not be direct result of the condition getting better but that people have learnt to manage their symptoms. For example, they may learn to avoid triggers such as interpersonal relationships. This may not be ideal as avoidance and living a solitary life aren’t considered healthy approaches.


Furthermore, it’s been said that as people age, they begin to engage in less impulsive behaviour and it becomes a less prevalent symptom of BPD.