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Medical Author:

Roxanne Dryden-Edwards, MD

Roxanne Dryden-Edwards, MD

Dr. Roxanne Dryden-Edwards is an adult, child, and adolescent psychiatrist. She is a former Chair of the Committee on Developmental Disabilities for the American Psychiatric Association, Assistant Professor of Psychiatry at Johns Hopkins Hospital in Baltimore, Maryland, and Medical Director of the National Center for Children and Families in Bethesda, Maryland.

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Medical Editor:

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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The causes of schizophrenia are not known. However, an interplay of genetic, biological, environmental, and psychological factors are thought to be involved. We do not yet understand all the causes and other issues involved, but current research is making steady progress toward elucidating and defining causes of schizophrenia. Schizophrenia and bipolar disorder are thought to have many risk factors in common.

In biological models of schizophrenia, genetic (familial) predisposition, infectious agents, allergies, and disturbances in metabolism have all been investigated.

Schizophrenia is known to run in families. Thus, the risk of illness in an identical twin of a person with schizophrenia is 40%-50%. A child of a parent suffering from schizophrenia has a 10% chance of developing the illness. The risk of schizophrenia in the general population is about 1%.

The current concept is that multiple genes are involved in the development of schizophrenia and that risk factors such as prenatal (intrauterine), perinatal, and nonspecific stressors are involved in creating a disposition or vulnerability to develop the illness. Neurotransmitters (chemicals allowing the communication between nerve cells) have also been implicated in the development of schizophrenia. The list of neurotransmitters under scrutiny is long, but special attention has been given to dopamine, serotonin, and glutamate.

Also, recent research studies have identified subtle changes in brain structure and function, indicating that, at least in part, schizophrenia could be a disorder of the development of the brain.

Environmental risk factors, like a history of using marijuana, have also been associated with the development of schizophrenia.

It is important for doctors to investigate all reasonable medical causes for any acute change in someone's mental health or behavior. Sometimes a medical condition that might be treated easily, if diagnosed, is responsible for symptoms that resemble those of schizophrenia.

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