Causes of suicide
Despite being a leading cause of death, both in England and worldwide, there is little hard evidence to explain why some people commit suicide while other people in similar circumstances do not. However, some important factors that make suicide more likely have been identified. These are explained below.
Vulnerability to suicide
Many experts believe that several factors determine how vulnerable a person is to suicidal thinking and behaviour.
Factors that make someone more vulnerable include:
- genetics and family history - see below
- life history - for example having a traumatic experience during childhood, such as a bereavement
- mental health - for example developing a serious mental health condition, such as schizophrenia
- lifestyle - people who misuse alcohol and drugs are at increased risk of suicidal thoughts
- job - poor job security, low levels of job satisfaction or not having a job can increase a person s risk of dying by suicide
- relationships - people who are socially isolated and have few close relationships with others have a higher risk of dying by suicide
As well as these factors, one or more stressful events may push a person "over the edge" and lead to suicidal thinking and behaviour. The amount of stress it takes to do this will depend on the person s level of vulnerability.
In some cases, it may only take a minor event, such as having an argument with a partner. In other cases, it may take one or more very stressful or upsetting events before a person feels suicidal, such as a partner dying or being diagnosed with a terminal illness.
In many cases, it may take a combination of different factors to increase a person's risk of suicidal thoughts.
Mental health conditions
Having a mental health condition is the most significant risk factor for suicide.
It is estimated that 90% of people who attempt or die by suicide have one or more mental health conditions. The mental health conditions that lead to the biggest risk of suicide are described below.
Severe depression
Severe depression is where a person has severe symptoms of despair and hopelessness that interfere with their life. People with severe depression are 20 times more likely to attempt suicide than the general population.
Bipolar disorder
Bipolar disorder is where a person swings from feeling very high and happy to feeling very low and depressed. About 1 in 3 people with bipolar disorder will attempt suicide at least once, and 1 in 10 people with the condition will take their own life.
Schizophrenia
Schizophrenia is a long-term mental health condition that causes hallucinations (seeing or hearing things that are not real), delusions (believing in things that are not true) and changes in behaviour. It is estimated that 1 in 20 people with schizophrenia will take their own life.
People with schizophrenia are most at risk of suicide when their symptoms first begin. The risk reduces as they learn to cope with their condition.
Borderline personality disorder
Borderline personality disorder is characterised by unstable emotions, disturbed thinking patterns, impulsive behaviour and intense but unstable relationships with other people. It is estimated that just over half of people with borderline personality disorder will make at least one suicide attempt.
People with a borderline personality disorder who have a history of childhood sexual abuse have a particularly high risk of suicide.
Anorexia nervosa
Anorexia nervosa is where a person is very anxious about their weight and keeps it as low as possible by strictly controlling and limiting what they eat. It is estimated that around 1 in 5 people with anorexia will make at least one suicide attempt.
Generalised anxiety disorder
Generalised anxiety disorder is where a person has persistent, recurring feelings of stress and anxiety.
Other risk factors for suicide
Other factors that can increase the risk of suicide include:
- having a history of sexual or physical abuse
- having a history of parental neglect, either emotional or physical neglect or both
- having a parent with a serious mental health condition, such as severe depression or schizophrenia
- having a parent who died by suicide
- having previously attempted suicide
- being socially isolated, such as living alone or having few close friends or family members
- being gay, arising from the prejudice that gay people often face
- being unemployed, having poor job security or working in an unskilled occupation
- being in debt
- being homeless
- being recently released from prison
- having recently experienced a traumatic event, such as the end of a relationship or the death of a loved one
- misusing drugs or misusing alcohol
- working in an occupation that provides access to potential ways of dying by suicide, such as working as a doctor, nurse, pharmacist, farmer or as member of the armed services
Antidepressants and suicide risk
Research has found that young people under 25 years of age have a small increased risk of suicide or having suicidal thoughts when taking antidepressants, usually when they first begin treatment.
Contact your GP immediately or go to your local hospital if you have thoughts of killing or harming yourself at any time while taking antidepressants.
It may be useful to tell a relative or close friend that you have started taking antidepressants and to ask them to read the leaflet that comes with your medication. Ask them to tell you if they think your symptoms are getting worse or if they are worried about changes in your behaviour.
Genetics and suicide
It has been known for some time that suicide can run in families. This has led to speculation that certain genes may be associated with suicide.
Recent research has identified several genetic mutations that may disrupt the chemical make-up of the brain, making a person more vulnerable to suicidal thinking and behaviour.
A mutation is where the normal genetic instructions inside the cells become scrambled so that some cells do not work in the way that they should. However, it would be too simple to claim that there is a "suicide gene" and that whoever had a copy of that gene would attempt suicide.
Suicide is not just a matter of biology. It is a complex phenomenon and a wide range of factors is involved. However, a better understanding of the genetics associated with suicide may eventually make it possible to screen people who are at risk and to provide them with treatment and support.
A newer theory of suicide
A newer theory about suicide, devised by an American psychologist called Thomas Joiner, states that three main factors can cause someone to turn to suicide. They are:
- a perception (usually mistaken) that they are alone in the world and that no one really cares about them
- a feeling (again usually mistaken) that they are a burden on others and that people would be better off if they were dead
- fearlessness towards pain and death
The last factor poses the biggest risk that someone will go through with a successful suicide attempt.
The theory argues that fearlessness towards pain and self-harm may be learnt over time, which could explain the strong association between self-harming behaviour and suicide.
People who are regularly exposed to the suffering and pain of others may develop this fearlessness over time. This could help explain why suicide rates are higher in occupations that are linked to such exposure, such as soldiers, nurses and doctors.
