A serious mental disorder in which there are disturbed emotions, disorganized thinking, and an inability to function socially

  • Usually develops in males aged 15–25 and females aged 25–35
  • Sometimes runs in families
  • Stressful life events are risk factors
  • Gender is not a significant factor

Schizophrenia is a severe and disruptive mental illness that occurs in all cultures and affects about 1 in 100 people worldwide. Although the term is sometimes used mistakenly to refer to a split personality, schizophrenia is actually an impairment of a person’s sense of reality that leads to irrational behaviour and disturbed emotional reactions. People with schizophrenia may hear voices, and this may contribute to their bizarre behaviour. In addition, they are usually unable to function at work or maintain relationships with other people.

Without proper support and treatment, people with schizophrenia are likely to neglect or harm themselves. About 1 in 10 people with the condition commits suicide (see Attempted suicide and suicide).

Brain activity in schizophrenia

PET scans show a distinctive pattern of large areas of low activity in the brain of a person with schizophrenia when compared with the brain of an unaffected person.

What are the causes?

No single cause of schizophrenia has been identified, but genetic factors are known to play a major part. A person who is closely related to someone with schizophrenia has a significantly increased risk of developing the disorder. In addition, a stressful life event, such as a serious illness or a bereavement, may trigger the disorder in a person who is susceptible. Evidence also points to abnormalities in brain structure, such as enlarged fluid-filled cavities that suggest loss of brain tissue.

What are the symptoms?

Schizophrenia tends to develop in men during their teens or early 20s, but the onset in women may be 10–20 years later. The condition usually develops gradually, with the person losing energy and personal motivation and becoming increasingly withdrawn over a period of months or years. In other cases, the illness is more sudden and may be a response to an episode of stress. Some people have clear-cut episodes of illness and recover completely in between. In other cases, the disorder is more or less continuous. Symptoms may include:

  • Hearing hallucinatory voices.

  • Having irrational beliefs, in particular that thoughts and actions are being controlled by an outside force.

  • Delusions of persecution or a conviction that trivial objects and events have deep significance.

  • Expression of inappropriate emotions, such as laughing at bad news.

  • Rambling speech with rapid switching from one topic to another.

  • Impaired concentration.

  • Disordered thoughts.

  • Agitation and restlessness.

A person with schizophrenia may be depressed, lethargic, and socially withdrawn. He or she may begin to neglect personal care and become increasingly isolated. In some cases, alcohol or drug abuse may occur.

How is it diagnosed?

If you are worried that a close friend or family member is suffering from schizophrenia, you should contact a doctor. Normally, the doctor will look for evidence of a profound break with reality, disturbed emotions, and strange beliefs lasting for several months before considering a diagnosis of schizophrenia. He or she will carry out a full physical examination, and blood or urine tests may be arranged to exclude other possible causes of abnormal behaviour, such as alcohol or drug abuse. The doctor may arrange for imaging of the brain by CT scanning or MRI to exclude an underlying physical disorder, such as a brain tumour.

What is the treatment?

If schizophrenia is suspected, it may be necessary to admit the person to hospital for further assessment and to begin treatment. Antipsychotic drugs are prescribed to help to calm the affected person and control symptoms such as hallucinations and delusions. Up to 6 weeks of treatment may be needed to reduce the more obvious symptoms of schizophrenia. Some drugs may cause serious side effects, such as tremors, and doses may have to be reduced or other drugs prescribed to minimize these effects. Treatment with adjusted doses of drugs usually continues after symptoms have subsided.

After assessment and treatment, people with schizophrenia are usually sent home, but it is essential that they have support and a calm and unthreatening home environment. People who have schizophrenia need to be protected from stressful situations because anxiety may trigger symptoms. They also need frequent, regular contact with community mental health service workers, who will supervise their progress and wellbeing.

Counselling may be offered both to the person with schizophrenia and to family members. People close to the affected person should watch for signs of relapse and indications that the person is sinking into a general state of apathy and self-neglect.

What is the prognosis?

For most affected people, schizophrenia is a long-term illness. However, about 1 in 5 of those affected have one sudden episode from which they recover and lead a normal life. The majority have a number of episodes of severe symptoms that may require hospital stays, interspersed with periods of recovery. Drugs have improved the outlook for people with schizophrenia, but adequate community care and support is essential to prevent relapse. The outlook is worse for people who develop schizophrenia gradually while they are young.

From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.

The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.

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