About Personality Disorders

Each of us has characteristics which influence the way we think, feel and behave and makes us a unique individual.

It's possible that some people with these disorders never come into contact with the mental health services. Those who are given a diagnosis of personality disorder may feel, perhaps understandably, that they are being blamed or criticised or that they are somehow responsible for their problems.

There are different types of Personality Disorder, which are explained in more detail on the Types of personality disorder page.

How common is personality disorder?

Research from the Office of National Statistics states that as many as 5.4% of men have a personality disorder, and for women, it is 3.4%.

Personality disorders are found more in younger age groups (25-44 year age group) and are equally common between males and females.

In 1998, research carried out by the Office of National Statistics found that numbers of people with personality disorders are highest in institutional settings like prison, which has a population where 64% of male sentenced prisoners and 50% of female prisoners have been found to be suffering from a personality disorder.

Risks associated with personality disorder

Personality disorders are associated with suicidal behaviour although this varies considerably between the diagnoses (see Types of personality disorder).

People diagnosed as borderline or paranoid personality disorder may be at higher risk of self harm and/or suicide than other people. Because some personality - disordered people engage in impulsive and dangerous behaviour they have an increased mortality rate.

Antisocial personality disorder is associated with a significant increase in unnatural causes of death (largely suicide, accidents and homicides).

There is also a strong association between personality disorders and substance misuse. It is estimated that 35-55% of people with substance misuse problems also have symptoms of a personality disorder with the most prevalent being antisocial personality disorder.

What is the connection between personality disorder and substance misuse?

It has been suggested that the combination of personality disorder and street drug or alcohol misuse is the most common form of Dual diagnosis (when substance misuse and mental illness occur together).

Young People with personality disorder are particularly at risk. According to the Royal College of Psychiatrists, a recent study found that 15% of 16-24 year olds with personality disorder report using a drug in the last year. People with a diagnosis of a cluster B personality disorder are more likely to misuse substances.

There are many reasons why people with personality disorders and other mental health problems turn to drugs and or alcohol. They may feel anxious or wish to ‘block out’ symptoms or side-effects of various medications.

They may feel bored and isolated, lonely, marginalised and depressed. They may have sleeping difficulties or hope to boost their self-confidence and feel ‘normal’.

Rethinks believes it’s important that the mental health services and drug and alcohol agencies come together to treat the individual. Sadly, this kind of service is not often available, and individuals are more likely to be referred to a substance misuse service than a mental health service. 

See our factsheet on Dual diagnosis factsheet for more detailed information about mental health and substance misuse.

Personality disorder and other mental disorders

One difficulty with personality disorders is that they can exist alongside a mental illness, such as depression or bipolar disorder, sometimes causing conflict around diagnoses and confusing issues around best treatment.

A second opinion may be useful in some cases.