Schizophrenia
Schizophrenia is a mental disorder characterized by loss of contact with reality (psychosis), hallucinations (usually, hearing voices), delusions (false beliefs), abnormal thinking, flattened affect (restricted range of emotions), diminished motivation, and disturbed work and social functioning.
Schizophrenia is a major health problem throughout the world. The disorder typically strikes young people at the very time they are establishing their independence and can result in lifelong disability and stigma. In terms of personal and economic costs, schizophrenia has been described as among the worst disorders afflicting humankind.
Schizophrenia is listed by the World Health Organization as the ninth leading cause of disability worldwide and affects about 1% of the population, although pockets where schizophrenia is more or less common have been identified. Schizophrenia affects men and women equally. In the USA, schizophrenia accounts for about 1 of every 5 Social Security disability days and 2.5% of all health care expenditures. Schizophrenia is more common than Alzheimer's disease and multiple sclerosis.
Determining when onset occurs is often difficult because unfamiliarity with symptoms may delay medical care for several years. The average age for the onset of schizophrenia is 18 for men and 25 for women. Onset in childhood or early adolescence (see Section 23, Chapter 286) is uncommon. Onset is also uncommon late in life.
Deterioration in social functioning can lead to substance abuse, poverty, and homelessness. People with untreated schizophrenia may lose contact with their families and friends and often find themselves living on the streets of large cities.
Causes
What precisely causes schizophrenia is not known, but current research suggests a combination of hereditary and environmental factors. Fundamentally, however, it is a biologic problem, not one caused by poor parenting or a mentally unhealthy environment. People who have a parent or sibling with schizophrenia have about a 10% risk of developing the disorder, compared with a 1% risk among the general population. An identical twin whose co-twin has schizophrenia has about a 50% risk of developing schizophrenia. These statistics suggest a hereditary risk.
Other causes may include problems that occurred before, during, or after birth, such as influenza infection during the 2nd trimester of pregnancy, oxygen deprivation at birth, low birth weight, and mother-infant blood type incompatibility.
Symptoms
The onset of schizophrenia may be sudden, over a period of days or weeks, or slow and insidious, over a period of years. Although the severity and types of symptoms vary among different people with schizophrenia, the symptoms are usually sufficiently severe as to interfere with the ability to work, interact with people, and care for oneself. In some people with schizophrenia, mental ability declines, leading to an impaired ability to pay attention, think in the abstract, and solve problems. The severity of mental impairment is a major determinant of overall disability in people with schizophrenia.
Symptoms may be triggered or worsened by environmental stresses, such as stressful life events. Drug use, including use of marijuana, may trigger or worsen symptoms as well. Overall, the symptoms of schizophrenia fall into three major groups: positive (nondeficit) symptoms, negative (deficit) symptoms, and cognitive impairment. A person may have symptoms from one, two, or all three groups.
Positive symptoms include delusions, hallucinations, thought disorder, and bizarre behavior. Delusions are false beliefs that usually involve a misinterpretation of perceptions or experiences. For example, people with schizophrenia may experience persecutory delusions, believing that they are being tormented, followed, tricked, or spied on. They may have delusions of reference, believing that passages from books, newspapers, or song lyrics are directed specifically at them. They may have delusions of thought withdrawal or thought insertion, believing that others can read their mind, that their thoughts are being transmitted to others, or that thoughts and impulses are being imposed on them by outside forces. Hallucinations of sound, sight, smell, taste, or touch may occur, although hallucinations of sound (auditory hallucinations) are by far the most common. A person may "hear" voices commenting on his behavior, conversing with one another, or making critical and abusive comments.
Thought disorder refers to disorganized thinking, which becomes apparent when speech is rambling, shifts from one topic to another, and loses its goal-directed quality. Speech may be mildly disorganized or completely incoherent and incomprehensible. Bizarre behavior may take the form of childlike silliness, agitation, or inappropriate appearance, hygiene, or conduct. Catatonia is an extreme form of bizarre behavior in which a person maintains a rigid posture and resists efforts to be moved or, in contrast, displays purposeless and unstimulated motor activity.
Negative symptoms of schizophrenia include blunted affect, poverty of speech, anhedonia, and asociality. Blunted affect refers to a flattening of emotions. The person's face may appear immobile; he makes poor eye contact and lacks emotional expressiveness. Events that would normally make a person laugh or cry produce no response. Poverty of speech refers to a diminishment of thoughts reflected in a decreased amount of speech. Answers to questions may be terse, perhaps one or two words, creating the impression of an inner emptiness. Anhedonia refers to a diminished capacity to experience pleasure; the person may take little interest in previous activities and spend more time in purposeless ones. Asociality refers to a lack of interest in relationships with other people. These negative symptoms are often associated with a general loss of motivation, sense of purpose, and goals.
Cognitive impairment refers to difficulty in concentrating and remembering, organizing, planning, and problem solving. Some people are unable to concentrate sufficiently to read, follow the story line of a movie or television show, or follow directions. Others are unable to ignore distractions or remain focused on a task. Consequently, work that involves attention to detail, involvement in complicated procedures, and decision making may be impossible.
 See the sidebar Disorders That Resemble Schizophrenia.
Types of Schizophrenia
Some researchers believe schizophrenia is a single disorder, whereas others believe it is a syndrome (a collection of symptoms) based on numerous underlying disorders. Subtypes of schizophrenia have been proposed in an effort to classify people into more distinct groups. However, among individuals, the subtype may change over time.
Paranoid schizophrenia is characterized by a preoccupation with delusions or auditory hallucinations; disorganized speech and inappropriate emotions are less prominent. Hebephrenic or disorganized schizophrenia is characterized by disorganized speech, disorganized behavior, and flat or inappropriate emotions. Catatonic schizophrenia is dominated by physical symptoms such as immobility, excessive motor activity, or the assumption of bizarre postures. Undifferentiated schizophrenia is characterized by a mixture of symptoms from the other subtypes: delusions and hallucinations, thought disorder and bizarre behavior, and negative symptoms.
Diagnosis
No definitive test exists to diagnose schizophrenia. A doctor makes the diagnosis on the basis of a comprehensive assessment of the person's history and symptoms. For a diagnosis of schizophrenia to be made, symptoms must persist for at least 6 months and be associated with significant deterioration of work, school, or social functioning. Information from family, friends, or teachers is often important in establishing when the disorder began.
Laboratory tests are often performed to rule out substance abuse or an underlying medical, neurologic, or hormonal disorder that can have features of psychosis. Examples of such disorders include brain tumors, temporal lobe epilepsy, thyroid disease, autoimmune disorders, Huntington's disease, liver disease, and side effects of drugs. Testing for drug abuse is sometimes warranted.
People with schizophrenia have brain abnormalities that may be seen on a computed tomography (CT) or magnetic resonance imaging (MRI) scan. However, the abnormalities are not specific enough to be of help in diagnosing schizophrenia.
Prognosis
Adherence to treatment is very important for people with schizophrenia. Without drug treatment, 70 to 80% of people with schizophrenia experience substantial recurrence of symptoms within the first year after diagnosis. Drugs taken continuously can reduce the relapse rate to about 20 to 30% and can lessen symptoms significantly in most people. After discharge from a hospital, a person with schizophrenia who does not take prescribed drugs is very likely to be readmitted within the year; taking drugs as directed dramatically reduces the likelihood of being readmitted.
Despite the proven benefit of drug therapy, half of people with schizophrenia do not take their prescribed drugs. Some do not recognize their illness and resist taking drugs. In other instances, unpleasant side effects lead people to decide to stop taking their drugs. Memory problems, disorganization, or simply a lack of money prevents others from taking their drugs.
Improving adherence to drug therapy is most successful when specific barriers to adherence are addressed. If side effects of drugs are a major problem, a change to a different drug may help. A consistent, trusting relationship with a doctor or other therapist helps some people with schizophrenia to accept their illness more readily and recognize the need for adhering to prescribed treatment.
Over longer periods, the prognosis of schizophrenia varies. In general, one third of people achieve significant and lasting improvement, one third achieve some improvement with intermittent relapses and residual disabilities, and one third experience severe and permanent incapacity. Factors associated with a better prognosis include sudden onset of the disorder, late age at onset, a good level of skills and accomplishments before becoming ill, and having the positive (nondeficit) subtype of the disorder. Factors associated with a poor prognosis include early age of onset, poor social and vocational functioning before becoming ill, a family history of schizophrenia, and having the negative (deficit) subtype of the disorder.
About 10% of people with schizophrenia commit suicide.
Treatment
The general goals of treatment are to reduce the severity of psychotic symptoms, prevent the recurrence of symptomatic episodes and the associated deterioration in functioning, and provide support to allow functioning at the highest level possible. Antipsychotic drugs, rehabilitation and community support activities, and psychotherapy represent the three major components of treatment.
Antipsychotic Drugs: Drugs can be effective in reducing or eliminating symptoms, such as delusions, hallucinations, and disorganized thinking. After the immediate symptoms have cleared, the continued use of antipsychotic drugs substantially reduces the probability of future episodes.
Unfortunately, antipsychotic drugs have significant side effects that can include sedation, muscle stiffness, tremors, weight gain, and motor restlessness. Antipsychotic drugs may also cause tardive dyskinesia, an involuntary movement disorder most often characterized by puckering of the lips and tongue or writhing of the arms or legs. Tardive dyskinesia may not go away even after the drug is discontinued. For tardive dyskinesia that persists, there is no effective treatment. Another side effect of antipsychotic drugs, although rare but potentially fatal, is neuroleptic malignant syndrome, which is characterized by muscle rigidity, fever, high blood pressure, and changes in mental function (for example, confusion and lethargy).
A number of new antipsychotic drugs that cause fewer side effects have become available. These drugs may relieve positive symptoms (such as hallucinations), negative symptoms (such as lack of emotion), and cognitive impairment (such as reduced mental functioning and attention span) to a greater extent than the older antipsychotic drugs.
Clozapine has proven to be effective in up to half of the people for whom other drugs do not work. However, clozapine can cause serious side effects, such as seizures or potentially fatal bone marrow suppression; thus, it is generally used only for people who have not responded to other antipsychotic drugs. People who take clozapine must have their white blood cell count measured weekly, at least for the first 6 months, so that clozapine can be discontinued at the first indication that the number of white blood cells is dropping.
Rehabilitation and Community Support Activities: Community support activities, such as on-the-job coaching, are directed at teaching the skills needed to survive in the community. These skills enable a person with schizophrenia to work, shop, care for himself, manage a household, and get along with others. Although hospitalization may be needed during severe relapses, and involuntary hospitalization may be needed if the person poses a danger to himself or others, the general goal is to have the person live in the community. To achieve this goal, some people may need to live in a supervised apartment or group home where someone can ensure that drugs are taken as prescribed.
A small number of people with schizophrenia are unable to live independently, either because they have severe and unresponsive symptoms or because they lack the skills necessary to live in the community. They usually require full-time care in a safe and supportive setting.
Psychotherapy: Generally, the goal of psychotherapy is to establish a collaborative relationship between the person, family, and doctor. That way the person might learn to understand and manage his disorder, to take antipsychotic drugs as prescribed, and to manage stresses that can aggravate the disorder. A good doctor-patient relationship is often a major determinant of successful treatment. Psychotherapy reduces symptoms in some cases and helps prevent relapse in others.
 See the drug table Antipsychotic Drugs.
See the sidebar Antipsychotic Drugs: How Do They Work?
See the sidebar What Is Neuroleptic Malignant Syndrome?
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