Instruct: Given a question, retrieve relevant passages that answer the question.
Query: How many people have schizophrenia?
Schizophrenia affects around 0.3–0.7% of people at some point in their life, or 21 million people worldwide as of 2011 (about one of every 285). By using precise methods in its diagnosis and a large, representative population, schizophrenia seems to occur with relative consistency over time during the last half-century.
Visual hallucinations occur in roughly a third of people with schizophrenia, although rates as high as 55% are reported. Content frequently involves animate objects, although perceptual abnormalities such as changes in lighting, shading, streaks, or lines may be seen. Visual abnormalities may conflict with proprioceptive information, and visions may include experiences such as the ground tilting. Lilliputian hallucinations are less common in schizophrenia, and occur more frequently in various types of encephalopathy (e.g. Peduncular hallucinosis).
In support of the above mentioned conclusions many studies have been performed. Doctors Lindamer, Lohr, Harris, and Jeste conducted a study to determine age of onset of schizophrenia in which they examined gender differences in 194 patients ranging in age from 35 to 97. They found that the mean age for onset in men was 30, while in women it was 39. (It is important to note that this is just one study, and overall averages come from a combination of different studies). About 37% of the women developed schizophrenia at the age of 45, while only 16% of men reported the same. Thus, more women than men experience late onset schizophrenia. This indicates that there is indeed another peak for women at the age of 45 and women do develop schizophrenia later in life.
Family studies on schizophrenia were reviewed. That the disorder runs in families did not suggest it was genetically inherited, since cultural transmission occurs from parents to children. Twin and adoption studies were presented as the standard methods to disentangle contributions from genes and the environment. Gottesman used a computer-based method for calculating the odds of becoming schizophrenic based on the many causes. The book examines the problems caused by schizophrenia for relatives of patients and for society at large, larger-scale ones exemplified by the eugenics policies of states such as Nazi Germany. Two final chapters cover molecular biology and neuroanatomy briefly. Newer methods of behavioral genetics being researched at the time of publication, such as linkage analysis which used the likelihood of neighboring genes being inherited together, were not covered.
The concept of schizophrenia as a result of civilization has been developed further by psychologist Julian Jaynes in his 1976 book "The Origin of Consciousness in the Breakdown of the Bicameral Mind"; he proposed that until the beginning of historic times, schizophrenia or a similar condition was the normal state of human consciousness. This would take the form of a "bicameral mind" where a normal state of low affect, suitable for routine activities, would be interrupted in moments of crisis by "mysterious voices" giving instructions, which early people characterized as interventions from the gods. Researchers into shamanism have speculated that in some cultures schizophrenia or related conditions (such as schizotypal personality disorder) may predispose an individual to becoming a shaman; the experience of having access to multiple realities is not uncommon in schizophrenia, and is a core experience in many shamanic traditions. Equally, the shaman may have the skill to bring on and direct some of the altered states of consciousness psychiatrists label as illness. Psychohistorians, on the other hand, accept the psychiatric diagnoses. However, unlike the current medical model of mental disorders they may argue that poor parenting in tribal societies causes the shaman's schizoid personalities. Commentators such as Paul Kurtz and others have endorsed the idea that major religious figures experienced psychosis, heard voices and displayed delusions of grandeur.
Dopamine is one of the chemicals that carries messages between brain cells. There is evidence that too much dopamine may be involved in the development of schizophrenia, but it’s still not clear how, or whether everyone diagnosed with schizophrenia has too much dopamine. Neuroleptic drugs (antipsychotics), which are sometimes used to treat schizophrenia, target the dopamine system.
Hallucinations of pain and touch are very rare in schizophrenic disorders but 20% of patients with schizophrenia experience some sort of tactile hallucinations along with visual and auditory hallucinations. The most common tactile hallucination in patients with schizophrenia is a sensation in which a patch of their skin is stretched elastically across their head. They vary in intensity, range and speed at which they feel this stretching painful sensation. They are usually triggered by emotional cues such as guilt, anger, fear and depression. Other types of tactile hallucinations takes on a sexual form in patients with schizophrenia. Patients with schizophrenia may sometimes experience the feeling of being kissed or the feeling of someone lying by their side in response to their emotion of being lonely. Additionally, they occasionally hallucinate the feeling of small animals such as snakes crawling over their body. Such vivid tactile sensation of an object that is not present results from the unsuccessful attempt of the brain trying to perceive objects that are novel and that represent unreal situations usually triggered by guilt and fear. Patients with schizophrenia also have a hard time portraying emotions as they divert most of their energy to control the pain from their tactile hallucinations.
The disorder presents symptoms such as auditory and visual hallucinations, strange thoughts or feelings, and abnormal behavior, profoundly impacting the child's ability to function and sustain normal interpersonal relationships. Delusions are often not systematized and vague. Among the actual psychotic symptoms seen in childhood schizophrenia auditory hallucinations are the most common. They are often presented in relatively simple form of akoasms (auditory hallucinations, such as noise, shots, knocks, etc.). Many of these children also have symptoms of irritability, searching for imaginary objects, or low performance. It typically presents after the age of seven. About 50% of young children diagnosed with schizophrenia experience severe neuropsychiatric symptoms. Studies have demonstrated that diagnostic criteria are similar to those of adult schizophrenia. Diagnosis is based on behavior observed by caretakers and, in some cases depending on age, self reports. Less than 5% of people with schizophrenia see their first symptoms before age 18.
The word "schizophrenia" was coined by the Swiss psychiatrist and eugenicist Eugen Bleuler in 1908, and was intended to describe the separation of function between personality, thinking, memory, and perception. He formally introduced the term on 24 April 1908 in a lecture given at a psychiatric conference in Berlin and in a publication that same year. Bleuler later expanded his new disease concept into a monograph in 1911, which was finally translated into English in 1950.
In 1908, Eugen Bleuler introduced the term ""schizophrenia"" to represent a revised disease concept for Emil Kraepelin's "dementia praecox." Whereas Kraepelin's natural disease entity was anchored in the metaphor of progressive deterioration and mental weakness and defect, Bleuler offered a reinterpretation based on dissociation or "splitting' ("Spaltung") and widely broadened the inclusion criteria for the diagnosis. A review of the "Index medicus" from 1903 through 1978 showed a dramatic decline in the number of reports of multiple personality after the diagnosis of schizophrenia became popular, especially in the United States. The rise of the broad diagnostic category of dementia praecox has also been posited in the disappearance of "hysteria" (the usual diagnostic designation for cases of multiple personalities) by 1910. A number of factors helped create a large climate of skepticism and disbelief; paralleling the increased suspicion of DID was the decline of interest in dissociation as a laboratory and clinical phenomenon.
Another typical disorder where auditory hallucinations are very common is dissociative identity disorder. In schizophrenia voices are normally perceived coming from outside the person but in dissociative disorders they are perceived as originating from within the person, commenting in their head instead of behind their back. Differential diagnosis between schizophrenia and dissociative disorders is challenging due to many overlapping symptoms, especially Schneiderian first rank symptoms such as hallucinations. However, many people not suffering from diagnosable mental illness may sometimes hear voices as well. One important example to consider when forming a differential diagnosis for a patient with paracusia is lateral temporal lobe epilepsy. Despite the tendency to associate hearing voices, or otherwise hallucinating, and psychosis with schizophrenia or other psychiatric illnesses, it is crucial to take into consideration that, even if a person does exhibit psychotic features, he/she does not necessarily suffer from a psychiatric disorder on its own. Disorders such as Wilson's disease, various endocrine diseases, numerous metabolic disturbances, multiple sclerosis, systemic lupus erythematosus, porphyria, sarcoidosis, and many others can present with psychosis.
It is not known exactly how common PCS is. Estimates of the prevalence at 3 months post-injury are between 24 and 84%, a variation possibly caused by different populations or study methodologies. The estimated incidence of PPCS (persistent postconcussive syndrome) is around 10% of mTBI cases. Since PCS by definition only exists in people who have suffered a head injury, demographics and risk factors are similar to those for head injury; for example, young adults are at higher risk than others for receiving head injury, and, consequently, of developing PCS.
A mild form of hallucination is known as a "disturbance", and can occur in most of the senses above. These may be things like seeing movement in peripheral vision, or hearing faint noises or voices. Auditory hallucinations are very common in schizophrenia. They may be benevolent (telling the subject good things about themselves) or malicious, cursing the subject, etc. Auditory hallucinations of the malicious type are frequently heard, for example people talking about the subject behind their back. Like auditory hallucinations, the source of the visual counterpart can also be behind the subject's back. Their visual counterpart is the feeling of being looked or stared at, usually with malicious intent. Frequently, auditory hallucinations and their visual counterpart are experienced by the subject together.
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")—was coined by Eugen Bleuler in 1908 and was intended to describe the separation of function between personality, thinking, memory, and perception. Bleuler described the main symptoms as four "A"'s: flattened "Affect", "Autism", impaired "Association" of ideas and "Ambivalence". Bleuler realized that the illness was not a dementia as some of his patients improved rather than deteriorated and hence proposed the term "schizophrenia" instead. However, many at the time did not accept that splitting or dissociation was an appropriate description, and the term would later have more significance as a source of confusion and social stigma than scientific meaning.
Command hallucinations are hallucinations in the form of commands; they can be auditory or inside of the person's mind or consciousness. The contents of the hallucinations can range from the innocuous to commands to cause harm to the self or others. Command hallucinations are often associated with schizophrenia. People experiencing command hallucinations may or may not comply with the hallucinated commands, depending on the circumstances. Compliance is more common for non-violent commands.
The incarceration rate of the People's Republic of China varies depending on sources and measures. According to the World Prison Brief, the rate for only sentenced prisoners is 118 per 100,000 (as of 2015). The rate for prisoners including estimations for the number of pre-trial detainees and those in administrative detention is 164 per 100,000 (as of 2015). In a 2010 interview Harry Wu, a U.S.-based human rights activist and ex-Chinese labor camp prisoner, estimates that "in the last 60 years, more than 40–50 million people" were in Chinese labor camps, but that period includes the mass incarcerations of the 1950s or the Cultural Revolution (1966-1976) and is not representative of modern China.
An incident of disinformation about coprolalia and Tourette's involved Dr. Laura Schlessinger. According to the former Tourette Syndrome Association (name changed to Tourette Association of America in 2015), she berated a caller inquiring whether a child with TS should attend a family wedding, declaring that a majority of those with the condition exhibited coprolalia and should be excluded from many social situations, provoking an avalanche of angry calls about the misinformation. Garrison Keillor, radio show host of NPR's "A Prairie Home Companion", produced a segment in 2006, titled "Broadway Tourette's", about segregating people with stereotypical TS from other passengers on a cruise ship, prompting a press release from the Tourette Syndrome Association.
Agnes Hann of the National Childbirth Trust said, "These findings are shocking, and mean that thousands of women experiencing potentially serious perinatal mental health problems are not getting the support they need. Perinatal mental illness can have a severe and long-term impact on mothers, babies and families. In extreme circumstances, it can result in tragedy – suicide is a leading cause of maternal death." From roughly 10% to 20% of women giving birth experience some type of mental illness such as anxiety and depression or more complex problems like PTSD and psychosis. With about 665,000 births a year in England 66,500–133,000 women a year develop illnesses. In 2016, 13,000 women were treated by perinatal teams while 800 became inpatients. This means the majority were untreated.
In World War I, shell shock was considered a psychiatric illness resulting from injury to the nerves during combat. The horrors of trench warfare meant that about 10% of the fighting soldiers were killed (compared to 4.5% during World War II) and the total proportion of troops who became casualties (killed or wounded) was 56%. Whether a shell-shock sufferer was considered "wounded" or "sick" depended on the circumstances. When faced with the phenomenon of a minority of soldiers mentally breaking down, there was an expectation that the root of this problem lay in character of the individual soldier, not because of what they experienced on the front lines during the war. These sorts of attitudes helped fuel the main argument that was accepted after the war and going forward that there was a social root to shell shock that consisted of soldiers finding the only way allowed by the military to show weakness and get out of the front, claiming that their mental anguish constituted a legitimate medical diagnosis as a disease. The large proportion of World War I veterans in the European population meant that the symptoms were common to the culture.
The rate of SLE varies between countries, ethnicity, and sex, and changes over time. In the United States, one estimate of the rate of SLE is 53 per 100,000; other estimates range from 322,000 to over 1 million. In Northern Europe the rate is about 40 per 100,000 people. SLE occurs more frequently and with greater severity among those of non-European descent. That rate has been found to be as high as 159 per 100,000 among those of Afro-Caribbean descent. Childhood-onset systemic lupus erythematosus generally presents between the ages of 3 and 15 and is four times more common in girls.
Estimates for the total casualties of World War II vary, but most suggest that some 60 million people died in the war, including about 20 million soldiers and 40 million civilians. The Soviet Union lost around 27 million people during the war, about half of all World War II casualties. The largest number of civilian deaths in a single city was 1.2 million citizens dead during the 872-day Siege of Leningrad. Based on 1860 census figures, 8% of all white American males aged 13 to 50 died in the American Civil War. Of the 60 million European soldiers who were mobilized in World War I, 8 million were killed, 7 million were permanently disabled, and 15 million were seriously injured.
In the first half of the 20th century schizophrenia was considered to be a hereditary defect, and sufferers were subject to eugenics in many countries. Hundreds of thousands were sterilized, with or without consent—the majority in Nazi Germany, the United States, and Scandinavian countries. Along with other people labeled "mentally unfit", many diagnosed with schizophrenia were murdered in the Nazi "Action T4" program.
Schizophrenia has great human and economic costs. It results in a decreased life expectancy by 10–25 years. 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. Antipsychotic medications may also increase the risk. These differences in life expectancy increased between the 1970s and 1990s.
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. Approximately three-fourths of people with schizophrenia have ongoing disability with relapses and 16.7 million people globally are deemed to have moderate or severe disability from the condition. Some people do recover completely and others function well in society. Most people with schizophrenia live independently with community support. About 85% are unemployed. Some evidence suggests that paranoid schizophrenia may have a better prospect than other types of schizophrenia for independent living and occupational functioning. 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%. Outcomes for schizophrenia appear better in the developing than the developed world. These conclusions have been questioned.
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. Several times more (20 to 40%) attempt suicide at least once. There are a variety of risk factors, including male gender, depression, and a high intelligence quotient.
Schizophrenia and smoking have shown a strong association in studies worldwide. Use of cigarettes is especially high in those diagnosed with schizophrenia, with estimates ranging from 80 to 90% being regular smokers, as compared to 20% of the general population. Those who smoke tend to smoke heavily, and additionally smoke cigarettes with high nicotine content. Some propose that this is in an effort to improve symptoms. Among people with schizophrenia use of cannabis is also common.
Schizophrenia is a complex disorder that affects about a half percent of the world's population. Typically, the first symptoms of schizophrenia typically appear in adolescence. In a genome-wide association study of 1,735 schizophrenic patients and 3,485 healthy adults, the Center identified copy number variations as a potential cause of the disorder. In the schizophrenia group, researchers located CNVs near the CACNA1B and DOC2A genes, both of which facilitate calcium signals that are important to neurotransmission in the brain. They also identified CNVs near the RET and RIT2 genes, which are known to be involved in brain development. Some of the regions associated with schizophrenia have previously been found to associate with autism and ADHD. This provides a strong indication that many psychiatric disorders stem share similar neurodevelopmental features.
Media coverage relating to violent acts by people with schizophrenia reinforces public perception of an association between schizophrenia and violence. In a large, representative sample from a 1999 study, 12.8% of Americans believed that those 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. The perception of people with psychosis as violent has more than doubled in prevalence since the 1950s, according to one meta-analysis.