Causes of personality disorder

Like other psychiatric illnesses, it is thought that personality disorders are caused by a number of factors. These include parental upbringing in childhood, personality, social development as well as genetic and biological factors.

Psychological causes

There is a body of research which shows that the many people with personality disorders have experienced trauma such as physical or sexual abuse. One piece of research found that up to 87% of those with borderline personality disorder experienced some sort of childhood trauma.

Abuse can be physical, sexual or involve neglect. Childhood is the time to learn to cope and manage intense emotional changes and form emotional attachments. Children who are abused often do not learn these lessons, thus they are more likely to have difficulty regulating their emotions as adults.

Not all people who have experienced trauma will have a personality disorder, but may become more vulnerable to having one.

Genetic causes

Research has looked at the inheritance of normal personality traits. This has suggested that some personality traits are more likely to be inherited (e.g. narcissism), while some (e.g. submissiveness) are less so. It has also been identified that individuals with certain personality disorders tend to have relatives with certain mental illnesses. For example, people with schizoid, paranoid and schizotypal personality disorders tended to have relatives with schizophrenia or schizophrenia-related conditions. People with dependent, avoidant and obsessive compulsive personality disorders tended to have relatives with an anxiety disorder.