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Schizophrenia has great human and economic costs.[4] It results in a decreased life expectancy by 10–25 years.[106] This is primarily because of its association with obesity, poor diet, sedentary lifestyles, and smoking, with an increased rate of suicide playing a lesser role.[4][106] Antipsychotic medications may also increase the risk.[106] These differences in life expectancy increased between the 1970s and 1990s.[107] Schizophrenia is a major cause of disability, with active psychosis ranked as the third-most-disabling condition after quadriplegia and dementia and ahead of paraplegia and blindness.[108] Approximately three-fourths of people with schizophrenia have ongoing disability with relapses[19] and 16.7 million people globally are deemed to have moderate or severe disability from the condition.[109] Some people do recover completely and others function well in society.[110] Most people with schizophrenia live independently with community support.[4] In people with a first episode of psychosis a good long-term outcome occurs in 42%, an intermediate outcome in 35% and a poor outcome in 27%.[111] Outcomes for schizophrenia appear better in the developing than the developed world.[112] These conclusions, however, have been questioned.[113][114] There is a higher than average suicide rate associated with schizophrenia. This has been cited at 10%, but a more recent analysis revises the estimate to 4.9%, most often occurring in the period following onset or first hospital admission.[6][115] Several times more (20 to 40%) attempt suicide at least once.[67][116] There are a variety of risk factors, including male gender, depression, and a high intelligence quotient.[116] Schizophrenia and smoking have shown a strong association in studies world-wide.[117][118] Use of cigarettes is especially high in individuals diagnosed with schizophrenia, with estimates ranging from 80 to 90% being regular smokers, as compared to 20% of the general population.[118] Those who smoke tend to smoke heavily, and additionally smoke cigarettes with high nicotine content.[119] Some evidence suggests that paranoid schizophrenia may have a better prospect than other types of schizophrenia for independent living and occupational functioning.[120] Epidemiology Disability-adjusted life year for schizophrenia per 100,000 inhabitants in 2004. no data ≤ 185 185–197 197–207 207–218 218–229 229–240 240–251 251–262 262–273 273–284 284–295 ≥ 295 Main article: Epidemiology of schizophrenia Schizophrenia affects around 0.3–0.7% of people at some point in their life,[4] or 24 million people worldwide as of 2011.[121] It occurs 1.4 times more frequently in males than females and typically appears earlier in men[1]—the peak ages of onset are 25 years for males and 27 years for females.[122] Onset in childhood is much rarer,[123] as is onset in middle- or old age.[124] Despite the received wisdom that schizophrenia occurs at similar rates worldwide, its frequency varies across the world,[67][125] within countries,[126] and at the local and neighborhood level.[127] It causes approximately 1% of worldwide disability adjusted life years[1] and resulted in 20,000 deaths in 2010.[128] The rate of schizophrenia varies up to threefold depending on how it is defined.[4] In 2000, the World Health Organization found the prevalence and incidence of schizophrenia to be roughly similar around the world, with age-standardized prevalence per 100,000 ranging from 343 in Africa to 544 in Japan and Oceania for men and from 378 in Africa to 527 in Southeastern Europe for women.[129] History Main article: History of schizophrenia In the early 20th century, the psychiatrist Kurt Schneider listed the forms of psychotic symptoms that he thought distinguished schizophrenia from other psychotic disorders. These are called first-rank symptoms or Schneider's first-rank symptoms. They include delusions of being controlled by an external force; the belief that thoughts are being inserted into or withdrawn from one's conscious mind; the belief that one's thoughts are being broadcast to other people; and hearing hallucinatory voices that comment on one's thoughts or actions or that have a conversation with other hallucinated voices.[130] Although they have significantly contributed to the current diagnostic criteria, the specificity of first-rank symptoms has been questioned. A review of the diagnostic studies conducted between 1970 and 2005 found that they allow neither a reconfirmation nor a rejection of Schneider's claims, and suggested that first-rank symptoms should be de-emphasized in future revisions of diagnostic systems.[131] The history of schizophrenia is complex and does not lend itself easily to a linear narrative.[132] Accounts of a schizophrenia-like syndrome are thought to be rare in historical records before the 19th century, although reports of irrational, unintelligible, or uncontrolled behavior were common. A detailed case report in 1797 concerning James Tilly Matthews, and accounts by Phillipe Pinel published in 1809, are often regarded as the earliest cases of the illness in the medical and psychiatric literature.[133] The Latinized term dementia praecox was first used by German alienist Heinrich Schule in 1886 and then in 1891 by Arnold Pick in a case report of a psychotic disorder (hebephrenia). In 1893 Emil Kraepelin borrowed the term from Schule and Pick and in 1899 introduced a broad new distinction in the classification of mental disorders between dementia praecox and mood disorder (termed manic depression and including both unipolar and bipolar depression).[134] Kraepelin believed that dementia praecox was probably caused by a long-term, smouldering systemic or "whole body" disease process that affected many organs and peripheral nerves in the body but which affected the brain after puberty in a final decisive cascade.[135] His use of the term "praecox" distinguished it from other forms of dementia such as Alzheimer's disease which typically occur later in life.[136] It is sometimes argued that the use of the term démence précoce in 1852 by the French physician Bénédict Morel constitutes the medical discovery of schizophrenia. However this account ignores the fact that there is little to connect Morel's descriptive use of the term and the independent development of the dementia praecox disease concept at the end of the nineteenth-century.[137] Molecule of chlorpromazine (trade name Thorazine), which revolutionized treatment of schizophrenia in the 1950s The word schizophrenia—which translates roughly as "splitting of the mind" and comes from the Greek roots schizein (σχίζειν, "to split") and phrēn, phren- (φρήν, φρεν-, "mind")[138]—was coined by Eugen Bleuler in 1908 and was intended to describe the separation of function between personality, thinking, memory, and perception. American and British interpretations of Beuler led to the claim that he described its main symptoms as 4 A's: flattened Affect, Autism, impaired Association of ideas and Ambivalence.[139][140] Bleuler realized that the illness was not a dementia, as some of his patients improved rather than deteriorated, and thus proposed the term schizophrenia instead. Treatment was revolutionized in the mid-1950s with the development and introduction of chlorpromazine.[141] In the early 1970s, the diagnostic criteria for schizophrenia were the subject of a number of controversies which eventually led to the operational criteria used today. It became clear after the 1971 US-UK Diagnostic Study that schizophrenia was diagnosed to a far greater extent in America than in Europe.[142] This was partly due to looser diagnostic criteria in the US, which used the DSM-II manual, contrasting with Europe and its ICD-9. David Rosenhan's 1972 study, published in the journal Science under the title "On being sane in insane places", concluded that the diagnosis of schizophrenia in the US was often subjective and unreliable.[143] These were some of the factors leading to the revision not only of the diagnosis of schizophrenia, but the revision of the whole DSM manual, resulting in the publication of the DSM-III in 1980.[144] The term schizophrenia is commonly misunderstood to mean that affected persons have a "split personality". Although some people diagnosed with schizophrenia may hear voices and may experience the voices as distinct personalities, schizophrenia does not involve a person changing among distinct multiple personalities. The confusion arises in part due to the literal interpretation of Bleuler's term schizophrenia (Bleuler originally associated Schizophrenia with dissociation and included split personality in his category of Schizophrenia[145][146]). Dissociative identity disorder (having a "split personality") was also often misdiagnosed as Schizophrenia based on the loose criteria in the DSM-II.[146][147] The first known misuse of the term to mean "split personality" was in an article by the poet T. S. Eliot in 1933.[148] Other scholars have traced earlier roots.[149] Society and culture See also: List of people with schizophrenia The term schizophrenia was coined by Eugen Bleuler. In 2002 the term for schizophrenia in Japan was changed from Seishin-Bunretsu-Byō 精神分裂病 (mind-split-disease) to Tōgō-shitchō-shō 統合失調症 (integration disorder) to reduce stigma.[150] The new name was inspired by the biopsychosocial model; it increased the percentage of patients who were informed of the diagnosis from 37 to 70% over three years.[151] A similar change was made in South Korea in 2012. [152] In the United States, the cost of schizophrenia—including direct costs (outpatient, inpatient, drugs, and long-term care) and non-health care costs (law enforcement, reduced workplace productivity, and unemployment)—was estimated to be $62.7 billion in 2002.[153] The book and film A Beautiful Mind chronicles the life of John Forbes Nash, a Nobel Prize-winning mathematician who was diagnosed with schizophrenia. Violence Individuals with severe mental illness including schizophrenia are at a significantly greater risk of being victims of both violent and non-violent crime.[154] Schizophrenia has been associated with a higher rate of violent acts, although this is primarily due to higher rates of drug use.[155] Rates of homicide linked to psychosis are similar to those linked to substance misuse, and parallel the overall rate in a region.[156] What role schizophrenia has on violence independent of drug misuse is controversial, but certain aspects of individual histories or mental states may be factors.[157] Media coverage relating to violent acts by individuals with schizophrenia reinforces public perception of an association between schizophrenia and violence.[155] In a large, representative sample from a 1999 study, 12.8% of Americans believed that individuals with schizophrenia were "very likely" to do something violent against others, and 48.1% said that they were "somewhat likely" to. Over 74% said that people with schizophrenia were either "not very able" or "not able at all" to make decisions concerning their treatment, and 70.2% said the same of money management decisions.[158] The perception of individuals with psychosis as violent has more than doubled in prevalence since the 1950s, according to one meta-analysis.[159] Research directions See also: Animal models of schizophrenia Research has found a tentative benefit in using minocycline to treat schizophrenia.[160] Nidotherapy or efforts to change the environment of people with schizophrenia to improve their ability to function, is also being studied; however, there is not enough evidence yet to make conclusions about its effectiveness.[161] |
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