Schizophrenia is a
severe mental illness characterized
by a variety of symptoms, including loss of contact with reality,
bizarre
behavior, disorganized thinking and speech, decreased emotional
expressiveness,
and social withdrawal. Usually only some of these symptoms occur in any
one
person. The term schizophrenia comes from Greek words meaning
“split
mind.” However, contrary to common belief, schizophrenia does not refer
to a
person with a split personality or multiple personality. (For a
description of
a mental illness in which a person has multiple personalities, see Dissociative
Identity
Disorder.) To observers, schizophrenia may seem like madness or
insanity.
Perhaps more than any
other mental illness,
schizophrenia has a debilitating effect on the lives of the people who
suffer
from it. A person with schizophrenia may have difficulty telling the
difference
between real and unreal experiences, logical and illogical thoughts, or
appropriate and inappropriate behavior. Schizophrenia seriously impairs a
person’s ability to work, go to school, enjoy relationships with others,
or
take care of oneself. In addition, people with schizophrenia frequently
require
hospitalization because they pose a danger to themselves. About 10
percent of
people with schizophrenia commit suicide, and many others attempt
suicide. Once
people develop schizophrenia, they usually suffer from the illness for
the rest
of their lives. Although there is no cure, treatment can help many
people with
schizophrenia lead productive lives.
Schizophrenia also carries
an enormous cost to society.
People with schizophrenia occupy about one-third of all beds in
psychiatric
hospitals in the United States. In addition, people with schizophrenia
account
for at least 10 percent of the homeless population in the United States (see
Homelessness). The National Institute of Mental Health has estimated
that
schizophrenia costs the United States tens of billions of dollars each
year in
direct treatment, social services, and lost productivity.
|
II
|
PREVALENCE
|
Approximately 1 percent
of people develop schizophrenia
at some time during their lives. Experts estimate that about 1.8 million
people
in the United States have schizophrenia. The prevalence of schizophrenia
is the
same regardless of sex, race, and culture. Although women are just as
likely as
men to develop schizophrenia, women tend to experience the illness less
severely, with fewer hospitalizations and better social functioning in
the
community.
|
III
|
SYMPTOMS
|
Schizophrenia usually
develops in late adolescence or early
adulthood, between the ages of 15 and 30. Much less commonly,
schizophrenia
develops later in life. The illness may begin abruptly, but it usually
develops
slowly over months or years. Mental health professionals diagnose
schizophrenia
based on an interview with the patient in which they determine whether
the
person has experienced specific symptoms of the illness.
Symptoms and functioning
in people with schizophrenia
tend to vary over time, sometimes worsening and other times improving.
For many
patients the symptoms gradually become less severe as they grow older.
About 25
percent of people with schizophrenia become symptom-free later in their
lives.
A variety of symptoms
characterize schizophrenia.
The most prominent include symptoms of psychosis—such as delusions and
hallucinations—as well as bizarre behavior, strange movements, and
disorganized
thinking and speech. Many people with schizophrenia do not recognize
that their
mental functioning is disturbed.
|
A
|
Delusions
|
Delusions are false beliefs
that appear obviously untrue to other people. For example, a person with
schizophrenia may believe that he is the king of England when he is not.
People
with schizophrenia may have delusions that others, such as the police or
the
FBI, are plotting against them or spying on them. They may believe that
aliens
are controlling their thoughts or that their own thoughts are being
broadcast
to the world so that other people can hear them.
|
B
|
Hallucinations
|
People with schizophrenia
may also experience
hallucinations (false sensory perceptions). People with hallucinations
see,
hear, smell, feel, or taste things that are not really there. Auditory
hallucinations, such as hearing voices when no one else is around, are
especially common in schizophrenia. These hallucinations may include two
or
more voices conversing with each other, voices that continually comment
on the
person’s life, or voices that command the person to do something.
|
C
|
Bizarre Behavior
|
People with schizophrenia
often behave bizarrely. They
may talk to themselves, walk backward, laugh suddenly without
explanation, make
funny faces, or masturbate in public. In rare cases, they maintain a
rigid,
bizarre pose for hours on end. Alternately, they may engage in constant
random
or repetitive movements.
|
D
|
Disorganized
Thinking and
Speech
|
People with schizophrenia
sometimes talk in incoherent
or nonsensical ways, which suggests confused or disorganized thinking.
In
conversation they may jump from topic to topic or string together
loosely
associated phrases. They may combine words and phrases in meaningless
ways or
make up new words. In addition, they may show poverty of speech,
in
which they talk less and more slowly than other people, fail to answer
questions or reply only briefly, or suddenly stop talking in the middle
of
speech.
|
E
|
Social
Withdrawal
|
Another common characteristic
of schizophrenia is social
withdrawal. People with schizophrenia may avoid others or act as though
others
do not exist. They often show decreased emotional expressiveness. For
example,
they may talk in a low, monotonous voice, avoid eye contact with others,
and
display a blank facial expression. They may also have difficulties
experiencing
pleasure and may lack interest in participating in activities.
|
F
|
Other Symptoms
|
Other symptoms of schizophrenia
include difficulties
with memory, attention span, abstract thinking, and planning ahead.
People with
schizophrenia commonly have problems with anxiety, depression, and
suicidal
thoughts. In addition, people with schizophrenia are much more likely to
abuse
or become dependent upon drugs or alcohol than other people. The use of
alcohol
and drugs often worsens the symptoms of schizophrenia, resulting in
relapses
and hospitalizations.
|
IV
|
CAUSES
|
Schizophrenia appears
to result not from a single cause, but
from a variety of factors. Most scientists believe that schizophrenia is
a
biological disease caused by genetic factors, an imbalance of chemicals
in the
brain, structural brain abnormalities, or abnormalities in the prenatal
environment. In addition, stressful life events may contribute to the
development of schizophrenia in those who are predisposed to the
illness.
|
A
|
Genetic Factors
|
Research suggests that
the genes one inherits strongly
influence one’s risk of developing schizophrenia. Studies of families
have
shown that the more closely one is related to someone with
schizophrenia, the
greater the risk one has of developing the illness. For example, the
children
of one parent with schizophrenia have about a 13 percent chance of
developing
the illness, and children of two parents with schizophrenia have about a
46
percent chance of eventually developing schizophrenia. This increased
risk
occurs even when such children are adopted and raised by mentally
healthy
parents. In comparison, children in the general population have only
about a 1
percent chance of developing schizophrenia.
|
B
|
Chemical
Imbalance
|
Some evidence suggests
that schizophrenia may result
from an imbalance of chemicals in the brain called neurotransmitters.
These
chemicals enable neurons (brain cells) to communicate with each other.
Some
scientists suggest that schizophrenia results from excess activity of
the
neurotransmitter dopamine in certain parts of the brain or from an
abnormal
sensitivity to dopamine. Support for this hypothesis comes from
antipsychotic
drugs, which reduce psychotic symptoms in schizophrenia by blocking
brain
receptors for dopamine. In addition, amphetamines, which increase
dopamine
activity, intensify psychotic symptoms in people with schizophrenia.
Despite
these findings, many experts believe that excess dopamine activity alone
cannot
account for schizophrenia. Other neurotransmitters, such as serotonin
and
norepinephrine, may play important roles as well.
|
C
|
Structural Brain
Abnormalities
|
Brain imaging techniques,
such as magnetic resonance
imaging and positron-emission tomography, have led researchers to
discover
specific structural abnormalities in the brains of people with
schizophrenia.
For example, people with chronic schizophrenia tend to have enlarged
brain
ventricles (cavities in the brain that contain cerebrospinal fluid).
They also
have a smaller overall volume of brain tissue compared to mentally
healthy
people. Other people with schizophrenia show abnormally low activity in
the
frontal lobe of the brain, which governs abstract thought, planning, and
judgment. Research has identified possible abnormalities in many other
parts of
the brain, including the temporal lobes, basal ganglia, thalamus,
hippocampus,
and superior temporal gyrus. These defects may partially explain the
abnormal
thoughts, perceptions, and behaviors that characterize schizophrenia.
|
D
|
Factors Before
and During
Birth
|
Evidence suggests that
factors in the prenatal
environment and during birth can increase the risk of a person later
developing
schizophrenia. These events are believed to affect the brain development
of the
fetus during a critical period. For example, pregnant women who have
been
exposed to the influenza virus or who have poor nutrition have a
slightly
increased chance of giving birth to a child who later develops
schizophrenia.
In addition, obstetric complications during the birth of a child—for
example,
delivery with forceps—can slightly increase the chances of the child
later
developing schizophrenia.
|
E
|
Stressful Events
|
Although scientists favor
a biological cause of
schizophrenia, stress in the environment may affect the onset and course
of the
illness. Stressful life circumstances—such as growing up and living in
poverty,
the death of a loved one, an important change in jobs or relationships,
or
chronic tension and hostility at home—can increase the chances of
schizophrenia
in a person biologically predisposed to the disease. In addition,
stressful
events can trigger a relapse of symptoms in a person who already has the
illness. Individuals who have effective skills for managing stress may
be less
susceptible to its negative effects. Psychological and social
rehabilitation
can help patients develop more effective skills for dealing with
stress.
|
V
|
TREATMENT
|
Although there is no cure
for schizophrenia, effective
treatment exists that can improve the long-term course of the illness.
With
many years of treatment and rehabilitation, significant numbers of
people with
schizophrenia experience partial or full remission of their symptoms.
Treatment of schizophrenia
usually involves a
combination of medication, rehabilitation, and treatment of other
problems the
person may have. Antipsychotic drugs (also called neuroleptics)
are the
most frequently used medications for treatment of schizophrenia.
Psychological
and social rehabilitation programs may help people with schizophrenia
function
in the community and reduce stress related to their symptoms. Treatment
of
secondary problems, such as substance abuse and infectious diseases, is
also an
important part of an overall treatment program.
|
A
|
Antipsychotic
Drugs
|
Antipsychotic medications,
developed in the mid-1950s, can
dramatically improve the quality of life for people with schizophrenia.
The
drugs reduce or eliminate psychotic symptoms such as hallucinations and
delusions. The medications can also help prevent these symptoms from
returning.
Common antipsychotic drugs include risperidone (Risperdal), olanzapine
(Zyprexa), clozapine (Clozaril), quetiapine (Seroquel), haloperidol
(Haldol),
thioridazine (Mellaril), chlorpromazine (Thorazine), fluphenazine
(Prolixin),
and trifluoperazine (Stelazine). People with schizophrenia usually must
take
medication for the rest of their lives to control psychotic symptoms.
Antipsychotic medications appear to be less effective at treating other
symptoms of schizophrenia, such as social withdrawal and apathy.
Antipsychotic drugs help
reduce symptoms in 80 to 90
percent of people with schizophrenia. However, those who benefit often
stop
taking medication because they do not understand that they are ill or
because
of unpleasant side effects. Minor side effects include weight gain, dry
mouth,
blurred vision, restlessness, constipation, dizziness, and drowsiness.
Other
side effects are more serious and debilitating. These may include muscle
spasms
or cramps, tremors, and tardive dyskinesia, an irreversible
condition
marked by uncontrollable movements of the lips, mouth, and tongue. Newer
drugs,
such as clozapine, olanzapine, risperidone, and quetiapine, tend to
produce fewer
of these side effects. However, clozapine can cause agranulocytosis,
a
significant reduction in white blood cells necessary to fight
infections. This
condition can be fatal if not detected early enough. For this reason,
people
taking clozapine must have weekly tests to monitor their blood.
|
B
|
Psychological
and Social
Rehabilitation
|
Because many patients
with schizophrenia continue to
experience difficulties despite taking medication, psychological and
social
rehabilitation is often necessary. A variety of methods can be
effective.
Social skills training helps people with schizophrenia learn specific
behaviors
for functioning in society, such as making friends, purchasing items at a
store, or initiating conversations. Behavioral training methods can also
help
them learn self-care skills such as personal hygiene, money management,
and
proper nutrition. In addition, cognitive-behavioral therapy, a type of
psychotherapy, can help reduce persistent symptoms such as
hallucinations,
delusions, and social withdrawal.
Family intervention programs
can also benefit people
with schizophrenia. These programs focus on helping family members
understand
the nature and treatment of schizophrenia, how to monitor the illness,
and how
to help the patient make progress toward personal goals and greater
independence. They can also lower the stress experienced by everyone in
the
family and help prevent the patient from relapsing or being
rehospitalized.
Because many patients
have difficulty obtaining or
keeping jobs, supported employment programs that help patients find and
maintain jobs are a helpful part of rehabilitation. In these programs,
the
patient works alongside people without disabilities and earns
competitive
wages. An employment specialist (or vocational specialist) helps the
person
maintain their job by, for example, training the person in specific
skills,
helping the employer accommodate the person, arranging transportation,
and
monitoring performance. These programs are most effective when the
supported
employment is closely integrated with other aspects of treatment, such
as
medication and monitoring of symptoms.
Some people with schizophrenia
are vulnerable to
frequent crises because they do not regularly go to mental health
centers to
receive the treatment they need. These individuals often relapse and
face
rehospitalization. To ensure that such patients take their medication
and
receive appropriate psychological and social rehabilitation, assertive
community treatment (ACT) programs have been developed that deliver
treatment
to patients in natural settings, such as in their homes, in restaurants,
or on
the street.
|
C
|
Associated
Problems
|
People with schizophrenia
often have other medical
problems, so an effective treatment program must attend to these as
well. One
of the most common associated problems is substance abuse. Successful
treatment
of substance abuse in patients with schizophrenia requires careful
coordination
with their mental health care, so that the same clinicians are treating
both
disorders at the same time.
The high rate of substance
abuse in patients
with schizophrenia contributes to a high prevalence of infectious
diseases,
including hepatitis B and C and the human immunodeficiency virus (HIV).
Assessment, education, and treatment or management of these illnesses is
critical for the long-term health of patients.
Other problems frequently
associated with schizophrenia
include housing instability and homelessness, legal problems, violence,
trauma
and post-traumatic stress disorder, anxiety, depression, and suicide
attempts.
Close monitoring and psychotherapeutic interventions are often helpful
in
addressing these problems.
|
VI
|
RELATED
DISORDERS
|
Several other psychiatric
disorders are closely related
to schizophrenia. In schizoaffective disorder, a person shows
symptoms
of schizophrenia combined with either mania or severe depression. Schizophreniform
disorder refers to an illness in which a person experiences
schizophrenic
symptoms for more than one month but fewer than six months. In schizotypal
personality
disorder, a person engages in odd thinking, speech, and
behavior, but usually does not lose contact with reality (see Personality
Disorders).
Sometimes mental health professionals refer to these disorders
together as schizophrenia-spectrum disorders.
