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As described in "Schizophrenia (Part one)", schizophrenia is a psychotic brain disorder characterized by distortions in the way a person perceives reality, thinks, acts, expresses emotions and relates to others. This article describes schizophrenia's potential causes and treatments.

It is believed that schizophrenia is caused by a combination of environmental and genetic factors¹⁰. Approximately one percent of the general population has schizophrenia, but it is seen in ten percent of those with a first-degree relative (parent, brother or sister) with the disorder2. People who have a second-degree relative (aunt, uncle, grandparent or cousin) with schizophrenia also develop the disorder more often than the general population3. Recently scientists from the Massachusetts Institute of Technology in the United States and RIKEN Brain Science Institute in Japan reported that the PPP3CC and other genes in the early growth response (EGR) gene family (specifically, EGR3) may be linked to the disease4. These genes are important in the signaling pathway for calineurin, a brain enzyme that plays a role in many neuronal functions whose disruption may lead to the disorganized thinking, attention deficits, and memory and language problems symptomatic of schizophrenia.

Scientists believe that an imbalance in certain complex, interrelated chemical reactions in the brain involving neurotransmitters such as dopamine, glutamate and possibly others plays a role in schizophrenia5. It is believed that several genes are associated with an increased risk of schizophrenia; however it is likely that environmental factors also contribute to the disorder. Researchers believe that factors such as exposure to viruses or malnutrition in the womb, problems during birth, and psychosocial factors such as stressful environmental conditions may play a role in the development of schizophrenia6.

Schizophrenia treatment focuses on eliminating the symptoms, since the disease's causes are still unknown. Antipsychotic drugs are available, but everyone reacts differently and sometimes several different medications must be tried before the most effective one is found. Atypical antipsychotics, developed in the 1990's, have overcome many of the side effects such as rigidity, muscle spasms, tremors and restlessness traditionally associated with antipyschotics7. However, they may cause weight gain and metabolic changes. Psychosocial treatment may also be effective in patients who are taking antipsychotic drugs and are in stable condition.^[viii] Illness management skills, cognitive behavior therapy, family education skills and self-help groups may help patients deal with certain aspects of schizophrenia such as difficulty with communication, motivation, work and maintaining relationships with others. It is very important to understand that schizophrenia is a chronic disease that requires constant management.

Due to recent advances in schizophrenia research, the ambiguity of the old term and the entrenched negative image of schizophrenia, the Japanese Society of Psychiatry and Neurology changed the Japanese term for the disease from "Seishin Bunretsu Byo" (mind-split-disease) to "Togo Shitcho Sho" (integration disorder) in 2002.^[ix] The new term refers to the vulnerability-stress model, and it implies that the disorder may be treated and that recovery is possible if advanced medications and psychosocial intervention is used.

Discussion questions

1. Please summarize the article. What is the main point of the article?
2. What causes schizophrenia?
3. What genes may be related to schizophrenia?
4. What types of drugs are used to treat schizophrenia?
5. What is psychosocial treatment?
6. Why was the Japanese term for schizophrenia changed?

References:

1. Mental health: Schizophrenia. WebMD. (Accessed 26 June 2007)
2. Schizophrenia. U.S. National Institutes of Mental Health. (Accessed 26 June 2007)
3. Schizophrenia. U.S. National Institutes of Mental Health. (Accessed 26 June 2007)
4. Study shows genetic link for schizophrenia. Massachusetts Institute of Technology. 20 February 2007. (Accessed 26 June 2007)
5. Schizophrenia. U.S. National Institutes of Mental Health. (Accessed 26 July 2007)
6. Schizophrenia. U.S. National Institutes of Mental Health. (Accessed 26 June 2007)
7. Schizophrenia. U.S. National Institutes of Mental Health. (Accessed 26 July 2007)
8. Schizophrenia. U.S. National Institutes of Mental Health. (Accessed 26 July 2007)
9. Sato M. Renaming schizophrenia: a Japanese perspective. World Psychiatry. 2006 February; 5(1): 53-55. (Accessed 26 July 2007)