Schizophrenia—one of the most complex mental disorders—involves a severe, chronic and disabling disturbance in the brain.

There is no known single cause responsible for schizophrenia. It is believed that a chemical imbalance in the brain is an inherited factor. But it's likely that many factors--genetic, behavioral, and environmental--play a role in its development.

Schizophrenia is considered to be multifactorially inherited. Multifactorial inheritance means that "many factors" are involved. The factors are usually both genetic and environmental, where a combination of genes from both parents in addition to unknown environmental factors, produce the trait or condition.

Schizophrenia Statistics

Statistics indicate that schizophrenia affects 2.7 million Americans. Schizophrenia affects men and women equally. But symptoms in men generally begin earlier than in women. In most cases, schizophrenia first appears in men during their late teens or early 20s. In women, schizophrenia often first appears during their 20s or early 30s.

A child born into a family with a schizophrenic family member has a greater chance of developing the disorder than a child born into a family with no history of schizophrenia. After a person has been diagnosed with schizophrenia, the chance for a sibling to also be diagnosed with it is 7 to 8 percent. If a parent has schizophrenia, the chance for a child to have the disorder is 10 to 15 percent. Risk increases with the number of affected family members.

The Puzzling Symptoms of Schizophrenia

One of the most puzzling characteristics of schizophrenia is the sudden start of its symptoms. The symptoms of schizophrenia are often classified as positive (including delusions, hallucinations, and bizarre behavior) and negative (including social withdrawal and emotional unresponsiveness).

  • Positive Symptoms
  • Hallucinations (disordered perceptions) that may involve any of the five senses, including sight, hearing, touch, smell and taste
  • Delusions (distorted thoughts)
  • Disorganized speech
  • Unusual or disorganized behavior
  • Negative Symptoms
  • Restricted emotional range ("flat affect")
  • Limited, unresponsive speech with little expression
  • Disordered thinking, with problems making logical connections
  • Trouble starting or pursuing goal-directed activity

The symptoms of schizophrenia in children are similar to adults; however, children more often experience auditory hallucinations and typically do not experience delusions or formal thought disorders until mid-adolescence or older. The symptoms of schizophrenia may resemble other problems or psychiatric conditions. Always consult your doctor for a diagnosis.

Diagnosis and Treatment

A psychiatrist usually diagnoses schizophrenia. Other mental health professionals usually participate in completing a comprehensive mental health evaluation to determine individualized treatment needs.

Treatment for schizophrenia is complex. A combination of therapies is often necessary. Treatment is aimed at reducing the symptoms associated with the disorder. Types of treatment that may be helpful to an individual with schizophrenia may include antipsychotic medications and neuroleptics, individual and family psychotherapy (including cognitive and behavioral therapy), and support groups.

Medical Reviewer: [Mitchell, Roberta RN, MSN, CPNP, Pierce-Smith, Daphne RN, MSN, CCRC, FNP] Last Annual Review Date: 2009-08-12T00:00:00-06:00 Copyright: © 2000-2010 The StayWell Company, 780 Township Line Road, Yardley, PA 19067. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.

Reference: Mental Health and Behavior section on Better Medicine


What to Ask Your Doctor About Schizophrenia

Be prepared to ask the right questions at your next doctor’s appointment for schizophrenia.

Did You Know?

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