Schizophrenia

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Schizophrenia
Classification and external resources

A painting often used to help explain what a person with schizophrenia experiences.

ICD-10 F20.
ICD-9 295
OMIM 181500
DiseasesDB 11890
MedlinePlus 000928
eMedicine med/2072 emerg/520
MeSH F03.700.750

Schizophrenia is a mental disorder that may cause delusions, paranoia, hallucinations, disordered thinking and behaviour, and catatonia.[1] The symptoms usually begin between the ages of 16-30.

The word schizophrenia comes from two Greek words that mean to split and mind because there is a 'split' between what's going on in their minds and what's happening in reality. “Schizophrenia” is commonly misunderstood to mean that an affected persons has a "split personality". A person with schizophrenia may hear voices which sound as if they are coming from different people, the person with schizophrenia however does not change between different personalities; they have only one.[2] The condition in which a person has multiple personalities is dissociative identity disorder.

Schizophrenia has many different symptoms and not everyone with schizophrenia has all of them. For this reason, some scientists think that schizophrenia is actually many separate diseases that have some of the same symptoms. Schizophrenic "delusions" are actual perceptions that occur in or near the auditory system of the brain. The brain can not tell them apart from normal sounds that are heard. This is not yet fully understood by science. We can not say whether a schizophrenic person is hearing wavelengths other than normal or their own imagination.

There are many risk factors that might cause a person to develop schizophrenia. They include genetics; the disorder is known to run in families, and environmental factors which affect a developing fetus, such as viruses, oxygen deprivation and poor nutrition.

People with schizophrenia might also have other mental health disorders, including depression, anxiety and drug abuse.[3] They often have problems functioning in society, and have difficulty maintaining stable employment. However there are a small number of people with schizophrenia that are able to manage their symptoms and have earned college degrees and professional careers such as Elyn. R. Saks, a law professor at the University of Southern California and a published author.

Treatment of schizophrenia may include medication to help treat the symptoms, different types of psychotherapy, such as cognitive-behavioral therapy and various cognitive rehabilitation therapies such as Cognitive Remediation Therapy to help with the cognitive deficits associated with the disorder, which can be severe.

Phases[change | edit source]

Phases of Schizophrenia[4]
Phase I Phase II Phase III Phase IV
Premorbid Pre-psychotic Prodrome Acute Psychosis Chronic Illness
Features Genetic vulnerability, Environmental Exposure Cognitive, behavioral, social deficits; seeking help Loss of insight, abnormal thought and behavior, remitting-relapsing course Loss of function, medical complications,
Diagnosis Genetic sequence, family history SIPS*, cognitive assessment, neuroimaging Clinical interview, Clinical interview,
Disability None, mild cognitive deficit Change in school and social function Acute loss of function, acute family distress Chronic disability, unemployment, homelessness, incarceration
Intervention Unknown Cognitive training? PUFA?*, Family support? Medication, Psychosocial interventions Medication, psychosocial interventions, rehabilitation services
SIPS = Structured Interview for Prodromal Syndromes
PUFA = polyunsaturated fatty acids. Levels are reduced in people with schizophrenia.

Symptoms[change | edit source]

Disorganized thinkingA cloth embroidered by a person with schizophrenia, a written example of a "word salad"; a meaningless mixture of words and phrases. This is one example of the disorganized thinking caused by the disorder.
Disorganized thinking
A cloth embroidered by a person with schizophrenia, a written example of a "word salad"; a meaningless mixture of words and phrases.

This is one example of the disorganized thinking caused by the disorder.

Emotion-matching taskThis task involves picking one of the images at the bottom that expresses the same emotion as the one at top. People with schizophrenia often have difficulty recognizing facial emotions.[5]
Emotion-matching task
This task involves picking one of the images at the bottom that expresses the same emotion as the one at top. People with schizophrenia often have difficulty recognizing facial emotions.[5]

The symptoms of schizophrenia fall into three main categories: positive symptoms, negative symptoms, and cognitive symptoms.[6]

  • Positive symptoms
Positive symptoms are thoughts, behaviors, or sensory perceptions - like hearing voices that are not really there - that a person with a mental disorder has but healthy people do not have. They are called 'positive' not because they are good but because they are "added on". The symbol for add is the plus sign +; it is also the sign for the word "positive". These symptoms may include having strange thoughts that do not make sense (delusions),disorganized thoughts and speech, and feeling, hearing, seeing, smelling, or tasting things that do not exist (hallucinations).[7] Positive symptoms usually respond to drug treatment.[8]
  • Negative symptoms
Negative symptoms are thoughts, behaviors or emotions normally present in a healthy person that a person with a mental disorder has less of or may not have at all, they are 'minus' these. The sign for minus is -; it is also the sign for the word "negative". Negative symptoms includes a 'flat affect'; having a blank inexpressive look on the face and/or a monosyllabic speech spoken in a slow monotone, few gestures, lack of interest in anything including other people, inabilty to act spontaneously or feel pleasure.
  • Cognitive symptoms (or cognitive deficits)
Cognitive symptoms are problems with attention, certain types of memory, concept of time, and the ability to plan and organize. Cognitive deficits caused by schizophrenia can also be difficult to recognize as part of the disorder. They are the most disabling of the symptoms because cognitive problems affect everyday functioning.

Pre-onset symptoms

Around 40 percent of men and 23 percent of women who have schizophrenia had "pre-onset" signs of schizophrenia before they were 19 years old.[9] This "pre-onset" phase can occur as long as 30 months before symptoms begin.[10] During the pre-onset phase, people who go on to develop schizophrenia might have brief or self-limiting serious or violent symptoms,[11] as well as the non-specific symptoms of social withdrawal, annoyance, a general feeling of extreme unhappiness,[12] and clumsiness.[13]

Violent behavior A minority of people with schizophrenia have an increased risk for aggressive behavior. The risk for aggressive behavior increases with comorbid alcohol abuse, substance abuse, antisocial personality, or neurological impairment. Individuals with severe mental illness such as schizophrenia have a greater risk of being victims of violence.[14]

Causes[change | edit source]

Schizophrenia risk factors.

A combination of a person’s genes and environment plays a role in the development of schizophrenia.[15][16] People who have a family history of schizophrenia and who experienced a brief period of psychotic symptoms have a 20- to 40-percent chance of being diagnosed one year later.[17]

Inherited factors

Estimates of whether schizophrenia is inherited vary because separating the effects of a person’s genes and environment is difficult.[18] The greatest risk (6.5 percent) for developing schizophrenia is having a first-degree relative with the condition. When a person with schizophrenia has an identical twin, that twin also has the condition in more than 40 percent of the cases.[16] Many genes are probably involved, each to a small degree.[16] In the largest study of its kind, it was found that schizophrenia, autism, major depression, and bipolar disorder and ADHD, are genetically linked. They have the same differences in four regions of the DNA.

Environmental factors

Environmental factors that are risk factors for schizophrenia are drug use, stress before birth and in some cases exposure to infectious disease.[15] Living in an urban environment during childhood or as an adult has consistently been found to increase the risk of schizophrenia by a factor of two.[15][16] This is true even after taking into account drug use, ethnicity, and the size of one’s social group.[19] Other factors that play an important role include whether the person feels socially isolated, as well as social adversity, racial discrimination, failures in family functioning, unemployment, and poor housing conditions.[16][20] There is evidence that childhood experiences of abuse or trauma are risk factors for developing schizophrenia later in life.[21]

Neurotransmission

Neural signaling-human brain.gif

Action potentials


Neurons-axons-dendrites-synapses.PNG

Neurotransmitters


DTI-sagittal-fibers.jpg

Neural networks

An electrical impulse called an action potential travels down the axon of a neuron. At the end of the neuron the action potential causes the release of different chemicals called neurotransmitters, into the space - called the synapse - between that axon, and the axon or dendrite of the next neuron.

The neurotransmitters cross the synapse and set up the action potential in the next neuron. There are different types of neurotransmitters; dopamine, glutamate and serotonin, are three which are linked to the symptoms of schizophrenia. It could be there is too much of a neurotransmitter in one area of the brain or not enough in others. It is not yet known for sure.

The neurons in the brain are connected, and form pathways, which in turn form "neural networks", which is like the brains wiring. To complete a task -like recalling a memory - usually more than one region of the brain is involved, and the signals travel along the specific neural pathways in the neural network responsible for that type of task. People with schizophrenia have been shown to have problems that affect these neural networks.

Substance abuse Several drugs have been linked with the development of schizophrenia and the abuse of certain drugs and can cause symptoms like those of schizophrenia.[16][16][22] About half of those people who have schizophrenia use drugs or alcohol excessively possibly as coping mechanisms to deal with depression, anxiety, boredom, or loneliness.[23] Frequent marijuana use has been linked to twice the risk of serious mental illness and schizophrenia.[24]

Smoking

More people with schizophrenia smoke than the general population; it is estimated that at least 60% to as much as 90% of people with schizophrenia smoke. Recent research suggests that cigarette smoking may be a risk factor for developing schizophrenia.

Pre-birth factors

Factors such as oxygen deprivation, infection, or stress and lack of healthy foods in one’s mother during pregnancy, might result in a slight increase in the risk of schizophrenia later in life.[15] People who have schizophrenia are more likely to have been born in winter or spring (at least in the northern half of the world). This might relate to increased rates of exposures to viruses before birth.[16] This difference is about 5 to 8 percent.[25]

Brain structure

Enlarged lateral ventricles in schizophrenia.

People who have schizophrenia have differences in their brain structure compared to those who do not have the disorder. These differences are often in the parts of the brain that manage memory, organization, emotions, the control of impulsive behavior, and language.[26] Among these structural differences, are a reduction in brain volume in the frontal cortex and temporal lobes, and problems within the corpus callosum, the band of nerve fibers which connects the left side and the right side of the brain. People with schizophrenia also tend to have enlarged lateral and third ventricles. The ventricles are spaces within the brain filled with cerebrospinal fluid.[27]

Brain wiring

The human brain has 100 billion neurons, each one of these neurons are connected to many other neurons. One neuron may have as many as 20,000 connections; there is between 100 trillion and 500 trillion neural connections in the adult human brain. There are many different parts or 'regions' of the brain. To complete a task -like recalling a memory - usually more than one region of the brain is involved, and they are connected by neural networks which is like the brain's wiring. It is believed that there are problems with the brain's wiring in schizophrenia.

Diagnosis[change | edit source]

The DSM-IV-TR or the ICD-10 criteria are used to determine whether a person has schizophrenia.[15] These criteria use the self-reported experiences of the person and reported abnormalities in the behavior of the person, followed by a clinical assessment. A person can be determined to have the disease only if the symptoms are severe.[16]

Differential diagnosis[change | edit source]

There are various medical conditions, other psychiatric conditions and drug abuse related reactions that may mimic the symptoms of schizophrenia. For example delirium can cause visual hallucinations, or an unpredictable changing levels of consciousness. Schizophrenia occurs along with obsessive-compulsive disorder (OCD), a disorder in which a person becomes onsessed with certain ideas or actions. However, separating the obsessions of OCD from the delusions of schizophrenia can be difficult.[31]

Prevention[change | edit source]

There is no clear evidence that treating schizophrenia early is effective.[32] There is some evidence which shows that early treatment improves short term outcomes for people who have a serious episode of mental illness. These measures show little benefit five years later.[15] Attempting to prevent schizophrenia in the pre-onset phase is of uncertain benefit and so is not recommended (as of 2009).[33] Prevention is difficult because there are no reliable markers for the later development of the condition.[34]

Management[change | edit source]

Cognitive Remediation Therapy (CRT) is an 'evidence-based' therapy which helps to improve the cognitive deficits common in schizophrenia. The effects of CRT may be seen on fMRI scans of the brain.

The treatment of schizophrenia is based upon the phase of the illness the person is in. There are three treatment phases.

  • Acute Phase

The goals of treatment during the acute phase of treatment, defined by an acute psychotic episode, are to prevent harm, control disturbed behavior, reduce the severity of psychosis and associated symptoms (e.g., agitation, aggression, negative symptoms, affective symptoms), determine and address the factors that led to the occurrence of the acute episode, effect a rapid return to the best level of functioning, develop an alliance with the patient and family, formulate short- and long-term treatment plans, and connect the patient with appropriate aftercare in the community

  • Stabilization Phase

During the stabilization phase, the goals of treatment are to reduce stress on the patient and provide support to minimize the likelihood of relapse, enhance the patient’s adaptation to life in the community, facilitate continued reduction in symptoms and consolidation of remission, and promote the process of recovery. If the patient has improved with a particular medication regimen, continuation of that regimen and monitoring are recommended for at least 6 months.

  • Stable Phase

The goals of treatment during the stable phase are to ensure that symptom remission or control is sustained, that the patient is maintaining or improving his or her level of functioning and quality of life, that increases in symptoms or relapses are effectively treated, and that monitoring for adverse treatment effects continues. Regular monitoring for adverse effects is recommended. For most persons with schizophrenia in the stable phase, psychosocial interventions are recommended as a useful adjunctive treatment to pharmacological treatment and may improve outcomes [I]. Antipsychotic medications substantially reduce the risk of relapse in the stable phase of illness and are strongly recommended

Medication[change | edit source]

A 1960's era ad for Thorazine, a typical antipsychotic.

The first-line psychiatric treatment for schizophrenia is antipsychotic medication,[35] which can reduce the positive symptoms in about 7 to 14 days. However, medication fails to improve negative symptoms or problems in thinking significantly.[36][37]

About 40 to 50 percent of people have a good response to medication, 30 to 40 percent have a partial response, and 20 percent have an unsatisfactory response (after 6 weeks on two or three different drugs).[36] A drug called clozapine is an effective treatment for people who respond poorly to other drugs, but clozapine can lower the white blood cell count in 1 to 4 percent of people who take it. This is a serious side effect.[15][16][38]


For people who are unwilling or unable to take drugs regularly, injectable long-acting preparations of antipsychotics can be used.[39] When used in combination with mental and social interventions, such preparations can help people to continue their treatment.[39]

Psychosocial therapies[change | edit source]

Numerous mental and social interventions can be useful in treating schizophrenia. Such interventions include various types of therapy,[40] community-based treatments, supported employment, skills training, token economic interventions, and mental interventions for drug or alcohol use and weight management.[41] Family therapy or education, which addresses the whole family system of an individual, might reduce a return of symptoms or the need for hospitalizations.[40] The evidence for the effectiveness of cognitive behavioral therapy (also known as “talk therapy”) in reducing symptoms or preventing their return is minimal.[42][43]

Outlook[change | edit source]

Schizophrenia has great human and economic costs.[15] The condition results in a decreased life expectancy of 12 to 15 years, primarily because of its association with being overweight, not exercising, and smoking cigarettes. An increased rate of suicide plays a lesser role.[15] These differences in life expectancy increased between the 1970s and 1990s.[44]

Schizophrenia is a major cause of disability, with active psychosis ranked as the third-most-disabling.[45] Approximately three-fourths of people with schizophrenia have ongoing disability with symptoms that keep coming back.[36] Some people do recover completely and others function well in society.[46] Most people with schizophrenia live independently, with community support.[15] In people with a first episode of serious mental symptoms, 42 percent have a good long-term outcome. Thirty-five percent of the people have an intermediate outcome. Twenty-seven percent of the people have a poor outcome.[47] Outcomes for schizophrenia appear better in the developing world than in the developed world,[48] although that conclusion has been questioned.[49][50]

The suicide rate of people who have schizophrenia is estimated to be about 4.9 percent, most often occurring in the period following the first appearance of symptoms or the first hospital admission.[51] 20 to 40 percent try to kill themselves at least once.[52][53]

Schizophrenia and smoking have shown a strong association in studies worldwide.[54][55] Use of cigarettes is especially high in individuals who have schizophrenia, with estimates ranging from 80 to 90 percent of these people being regular smokers, as compared to 20 percent of the general population.[55] Those individuals who smoke tend to smoke heavily and smoke cigarettes with a high nicotine content.[53]

Research continues on Schizophrenia. In Spring of 2013, genetics associations were shown between five major psychiatric disorders: autism, ADHD, bipolar disorder, depression, and schizophrenia per recent study.[56][57] In the summer of 2013, for the first time brain tissue development was been replicated in three dimensions by scientists cloning a human "mini-brain" using stem cells. This could help with schizophrenia and autism neurological research. [58]

Likelihood[change | edit source]

As of 2011, schizophrenia affects around 0.3% to 0.7% of people,[15] or 24 million people worldwide,[59] at some point in their lives. More men are affected than women: the number of males with the disorder is 1.4 times greater than that of females. Schizophrenia usually appears earlier in men.[16] For males the symptoms usually start from 20 to 28 years of age, and in females it is 26 to 32 years of age.[60] Symptoms that start in childhood,[61] middle or old age are much rarer.[62] Despite the received wisdom that schizophrenia occurs at similar rates worldwide, its rate of likelihood varies across the world,[63] within countries,[64] and at the local level.[65] The disorder causes approximately 1% of worldwide disability adjusted life years (in other words, years spent with a disability).[16] The rate of schizophrenia varies depending on how it is defined.[15]

History[change | edit source]

Insulin coma therapy was often used for schizophrenia. Large doses of insulin would be injected into a person being treated causing them to go into a coma. Then glucose would be given to bring them back out of the coma.[66]

Accounts of a schizophrenia-like syndrome are rare before the 19th century. Detailed case reports from 1797 and 1809, are regarded as the earliest cases of the disorder.[67] Schizophrenia was first described as a distinct syndrome affecting teenagers and young adults by Bénédict Morel in 1853, termed démence précoce (literally 'early dementia'). The term dementia praecox was used in 1891 by Arnold Pick in a case report of a psychotic disorder. In 1893 Emil Kraepelin introduced a new distinction in the classification of mental disorders between dementia praecox and mood disorder (termed manic depression and including both unipolar and bipolar depression). Kraepelin believed that dementia praecox was primarily a disease of the brain,[68] and a form of dementia, different from other forms of dementia such as Alzheimer's disease which usually happen later in life.[69]

Eugen Bleuler coined the term ”schizophrenia”, which translates roughly as "split mind",[70] in 1908. The word was intended to describe the separation of functioning between personality, thinking, memory, and perception.[71] Bleuler realized that the illness was not a dementia because some of his patients improved rather than got worse.

In the early 1970s, the criteria for determining schizophrenia were the subject of numerous controversies. Schizophrenia was diagnosed far more often in the United States than in Europe.[72] This difference was partly the result of looser criteria for determining whether someone had the condition in the United States, where the DSM-II manual was used. In Europe, the ICD-9 manual was used. A 1972 study, published in the journal Science, concluded that the diagnosis of schizophrenia in the United States was often unreliable.[73] These factors resulted in the publication of the DSM-III in 1980 with a stricter and more defined criteria for the diagnosis.[74]

Society and culture[change | edit source]

Negative social judgement has been identified as a major obstacle in the recovery of people who have schizophrenia.[75]

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”), in an attempt to reduce feelings of shame or embarrassment.[76] The idea that the disease is caused by multiple factors (not just one mental cause) inspired the new name. The change increased the percentage of people who were informed of the diagnosis from 37 percent to 70 percent over three years.[77]

In the United States in 2002, the cost of schizophrenia, including direct costs (people who were not hospitalized, people who were hospitalized, medicines, and long-term care) and non-healthcare costs (law enforcement, reduced workplace productivity, and unemployment), was estimated to be $62.7 billion.[78]

The book “A Beautiful Mind” and the film of the same name are about the life of John Forbes Nash, an American mathematician and Nobel Prize winner who has schizophrenia. The movie The Soloist is based on the life of Nathaniel Ayers, a gifted musician who dropped out of the prestigious Julliard School, in New York City after the symptoms of schizophrenia began. He later became homeless in Los Angeles, California, in the notorious Skid Row section.

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