What is schizophrenia? Schizophrenia is a serious mental illness that affects one percent of the population. Characterized by psychosis and psychotic behavior, schizophrenia is one of the most misunderstood categories of mental illness.

Psychosis: Loss of Reality

Psychosis is defined as a loss of a sense of reality: Real and unreal events are difficult or impossible to distinguish. Psychosis may include delusions, hallucinations, confusion, and inarticulate, disorganized thoughts.

How a psychosis presents in an individual is referred to as psychotic behavior. For instance, if a schizophrenia patient's psychosis included disorganized thoughts, resulting psychotic behavior may include inarticulate speech and difficulty focusing on ideas.

Psychotic Behavior, Schizophrenia, and Other Mental Illness

While psychosis and psychotic behavior are integral to schizophrenia, not all cases of psychosis indicate schizophrenia. Mental disorders other than schizophrenia also produce psychotic behavior. A severe mood disorder such as depression or bipolar disorder may produce hallucinations and other psychosis.

Distinguishing between schizophrenia and other mental illness is vital, as treatments differ widely from one mental illness to another. Psychosis resulting from depression will disappear once depression treatment begins to work. Psychotic behaviors stemming from a different mental illness will not necessarily respond to schizophrenia medications.

So What is Schizophrenia?

Schizophrenia describes a state of social dysfunction and psychotic symptoms that last for at least six months. To be considered schizophrenia, psychosis symptoms must not be due to depression or other mental illness, nor can psychotic symptoms be traced to illicit drug use or medication side effects.

Schizophrenia Statistics and Incidence Rates

While incidence rates for other varieties of mental illness often vary from country to country, schizophrenia rates are remarkably stable across the globe. Internationally, one percent of the population experiences psychosis symptoms due to schizophrenia at some point in their lives. In developed countries, schizophrenia is one of the top ten causes of disability.

For example, an estimated two million Americans suffer from schizophrenia and psychotic symptoms annually. Schizophrenia patients fill an estimated 25 percent of U.S hospital beds, and the mental illness has a higher incidence rate than diabetes.

Gender and Schizophrenia

Schizophrenia affects men and women equally. Schizophrenia symptoms usually appear in men between the ages of 18 and 25. Women are more likely to develop schizophrenia symptoms between the ages of 25 and 45.

Cases of schizophrenia also occur in children and the elderly. While psychosis caused by schizophrenia occur in children as young as five, schizophrenia is rare before the teenage years.

Socioeconomics and Schizophrenia

Higher rates of schizophrenia are associated with low-income groups, most often in urban centers. The connection between schizophrenia and low socioeconomic status may be explained by the social effects of psychotic behavior, which often result in unemployment, social isolation, and poverty. Psychotic behavior often causes severe social dysfunction, which may explain why schizophrenia has higher rates in single people when compared to married individuals.

What Schizophrenia Is Not

Mental illness is often misrepresented in the media, and schizophrenia more often than most varieties of mental illness. Contrary to popular belief, schizophrenia does not indicate a "split" or multiple personality. Schizophrenia produces psychosis that often produces sudden behavioral changes, but schizophrenia patients do not have fragmented personalities.

Popular media often equates schizophrenia with violent, dangerous behavior. In part, this may be because "psychotic behavior" is popularly believed to be dangerous, "psycho" behavior. In fact, the term psychotic merely means being unable to distinguish reality from imaginary stimuli.

Studies indicate that schizophrenia sufferers are no more violent than other people, and that when violence does occur in a schizophrenia patient, the individual usually has a history of violence or criminal activity that predates schizophrenia onset.

Resources

Beers, M.H., & Berkow, R. (ed). Schizophrenia and related disorders. The Merck Manual of Diagnosis and Therapy, 17th Edition. Merck Research Laboratories, NJ, 1999.

Fauci, A., Braunwald, E., Isselbacher, K., Wilson, J., Martin, J., Kasper, D., Hauser, S. & Longo, D. (ed). Harrison's Principles of Internal Medicine, 14th Edition . McGraw-Hill, New York, 1998.

Murphy, M., Cowan, R. & Sederer, L. Blueprints in Psychiatry. Blackwell Publishing, Massachusetts, 2004.

National Library of Medicine. (updated 2004). Schizophrenia . MedlinePlus Medical Encyclopedia.

National Mental Health Information Center. (2003, April). Schizophrenia. NMHIC brochure [KEN98-0052].

Spearing, M.K. (2002, August). Schizophrenia [NIH Publication No. 02-3517]. National Institute of Mental Health.