‘Personality disorder’ is used to describe people who experience a particular set of difficulties in responding to others and to (especially stressful) situations in the same way that the majority of other people do.

• A sense of disconnection or feelings of emptiness
• Difficulty making and maintaining relationships with other people
• Difficulty in trusting other people or yourself
• Feelings of unfairness, or that others, or just the world or life, are out to get you
• Difficulty in coping with feelings without needing to ‘act out’ in some way, often quite dramatically
• Volatile and extreme emotional reactions that seem (to others anyway) disproportionate to the circumstances
• Non-specific feelings of anger or rage that are easily inflamed in adverse situations or when others are ‘difficult’

Just as everybody's experience of a personality disorder will be unique to them, the cause will be equally unique.

There is no one cause of personality disorders; rather, they may arise due to a combination of environmental or social circumstances, early life experiences, and genetic factors.

People who have been exposed to trauma at an early age are more likely to develop what are called insecure attachment patterns and also to develop unstable and volatile emotions, which they find hard to regulate. They may have difficulty thinking things through, and may be impulsive as well as subject to volatile and extreme emotional responses. They may feel unable to manage these thoughts and feeling, and feel themselves and the world to be unpredictable, hostile or dangerous; they may struggle to form trusting relationships or even to trust themselves. These are symptoms of personality disorders. The symptoms are developmental responses to early trauma or neglect, with insufficient nurturing care present to enable the baby/infant/child to emotionally and cognitively process the ‘adverse events’ she or he experienced.

It is estimated that 1 in 20 people in the UK meet the diagnostic criteria for personality disorder, making it a very common mental health problem; however, not many of them will go on to receive a diagnosis. For the majority of these people, symptoms are mild, and they may find they only need help at times of stress, such as a bereavement or relationship breakdown, just as many other people do.

The diagnosis of a personality disorder may be made when you encounter difficulties in all aspects of your life, all or most of the time, as a result of your thoughts, feelings or behaviours, and you seek medical help: it essentially refers to a particular set of difficulties in effective social functioning. It is not usually given if a sudden change in personality has occurred as the result of a traumatic or unexpected life event (these tend to be considered affective disorders, though they are actually difficulties in processing exceptionally difficult events).

The diagnostic manuals used by psychiatrists denote many different types of personality disorders, but that is disputed by many other psychiatrists and psychology professionals; all the so-called different types certainly have many similarities and overlaps, and there has been a strong campaign to get the diagnostic manuals changed. A more exact diagnostic and descriptive term is perhaps ‘Developmental Trauma Disorder’, but this has not yet been included in the manuals.

The 10 types of personality disorders listed in the standard psychiatric diagnostic manuals are grouped into three categories or ‘clusters’. However, any individual person may have symptoms from a variety of types. 

It’s worth noting that most people feel all of the things listed below sometimes; what distinguishes personality disorder is that some or all of the feelings in the list are the person’s typical feelings, as well as the intensity with which they are felt, they are also often felt as somehow natural – they are as they are because that’s how life is – rather than being understood as originating in particular interactions, or as a result of particular thought or emotional processes.

These personality disorder types involve unusual patterns of thoughts and behaviours.

Paranoid Personality Disorder

• Difficulty in trusting others
• Seeing danger in everyday situations that others may not
• Expecting betrayal or hostility from others

Schizoid Personality Disorder

• Preference for being alone
• Little interest in building close relationships with others
• May display emotional coldness towards other people

Schizotypal Personality Disorder

• Difficulty in forging close relationships
• Upholding beliefs that others may call ‘unusual’ and feeling anxious around those who do not share these beliefs

These personality disorder types involve dramatic and emotional thoughts and behaviours that may continue to change.

Antisocial Personality Disorder

• Likely to act impulsively or recklessly
• Be easily bored
• A history of manipulating, exploiting, or violating the rights of others
• Tendency to be ruthless and to show little concern for how your actions affect others

Borderline Personality Disorder

• Trouble managing your emotions
• Likely to act impulsively and then regret your actions later
• May feel uncertain about how you see yourself

Histrionic Personality Disorder

• Revel in being the centre of attention
• Behaviour may be overly dramatic and feel emotions strongly
• Feeling dependent on the approval of others
• Being easily influenced by other people

Narcissistic Personality Disorder

• Sensitive to being rejected or ignored
• Likely to have a sense of being special or more deserving than others
• Lacking empathy, a tendency to take advantage of other people

These personality disorder types involve anxious and fearful thoughts and behaviours.

Avoidant Personality Disorder

• Likely to avoid social situations
• Fearful of being criticised, may feel you are not as good as others
• Feeling isolated and lonely, unwilling to make relationships or try new things due to a fear of rejection or of embarrassing yourself

Dependent Personality Disorder

• Likely to feel like you need support in order to make decisions
• Tendency to agree to things simply to avoid losing the support of others
• Have low self-confidence and are seen by others as submissive

Obsessive-Compulsive Personality Disorder

• Likely to need order and control, can be very inflexible
• Set unrealistically high standards for yourself and others
• Expect catastrophes if you or another makes a mistake
• Although the symptoms are similar, this is different to obsessive-compulsive disorder (OCD)

As noted above, the distinctness and usefulness of these sub-groups or categories are strongly contested by many clinicians and experts in working with people with personality disorders, and most people will experience feelings and thoughts from within various categories and clusters.

Also, note that modern neurological and developmental research strongly suggests that personality disorders arise as a result of developmental difficulties caused by exposure to early trauma or neglect, often compounded by further traumatic experiences throughout development (this is known as ‘complex’ or ‘compound trauma’).

A consequence of understanding personality disorder as the outcome of a developmental process affected by trauma is that there is the possibility of change. The evidence is strong that, with the right support, people with and without diagnosed personality disorder, but with the characteristic experiences, can and do change: the emotional difficulties can become much more manageable, life can become much more straightforward for you, and you can find yourself better able to build strong, stable and loving relationships with those around you.

Because personality disorders arise from damaging psychosocial experiences during the development process, most responses to personality disorders are psychosocial. There is no drug treatment for personality disorders, and indeed, drug treatments are unadvisable because of the tendency for people affected by developmental trauma disorders to become drug dependent. Therapy and psychosocial interventions work because people who have been damaged by adverse developmental experiences can, as it were, ‘re-grow’ and experience a positive developmental experience, and, with an experienced therapist who can provide an emotionally and psychologically safe and holding space within which to do so, they can work through and process some of the traumatising experiences/feelings and learn in the here-and-now to manage their emotions and their urge to act on them.

There are various forms of psychotherapy that have been found to be effective for people with personality disorders: these include psychodynamic or psychoanalytic psychotherapy or mentalisation-based therapy (a specific type of psychodynamic therapy), all of which are used within the NHS and schema therapy (a psychodynamics-influenced ‘third wave’ CBT approach). 

Many NHS therapy programmes use group therapy, although many people with experiences of personality disorder, especially at the severe end, find groups too difficult to be in, at least at the beginning of treatment. Most private therapists will offer individual therapy. The length and frequency of treatment depend to a large extent on the degree to which everyday life is challenging for the individual seeking treatment. Typically, therapy for someone with a diagnosis of personality disorder might consist of two to three years of twice-weekly therapy sessions, but some individual therapies go on longer or are shorter, and some people only attend weekly. Some people move between weekly and twice-weekly over the course of the therapy. You can discuss this with your therapist.

Not all psychotherapists work with people with personality disorders because it is a specialised area of work, and it is important to check that the therapist feels confident in working with someone with characteristics of personality disorder and that you trust them, as far as you are able to trust anyone when you first meet them. One of the difficulties some people with personality disorder symptoms experience when starting therapy is impatience, which appears behaviourally in ‘acting out’ and leaving therapy prematurely and feeling that it ‘doesn’t work’ or that the therapist is ‘rubbish’ -  worth watching out for (once you’ve decided that the therapist you’ve chosen is the right person for your therapy).

There are also residential programmes, therapeutic communities, peer-support systems, day programmes, and a range of other psychosocial interventions available to different degrees depending on where you live.

Updated August 21 2024