Suicide Risk
Suicide
is a serious danger in people who have schizophrenia. If an
individual tries to commit suicide or threatens to do so,
professional help should be sought immediately. People with
schizophrenia have a higher rate of suicide than the general
population. Approximately 10 percent of people with schizophrenia
(especially younger adult males) commit suicide. Unfortunately,
the prediction of suicide in people
with schizophrenia can be especially difficult.
What Causes Schizophrenia?
There is no known single cause of schizophrenia. Many diseases,
such as heart disease, result from an interplay of genetic,
environmental, and behavioral factors; and this may be the
case for schizophrenia as well. Scientists do not yet understand
all of the factors necessary to produce schizophrenia, but
all the tools of modern biomedical research are being used
to search for genes, critical moments in brain development,
and environmental factors that may lead to the illness.
Is Schizophrenia Genetic?
It has long been known that schizophrenia runs in families.
People who have a close relative with schizophrenia are more
likely to develop the disorder than are people who have no
relatives with the illness. For example, a monozygotic (identical)
twin of a person with schizophrenia has the highest risk --
40 to 50 percent -- of developing the illness. A child whose
parent has schizophrenia has about a 10 percent chance. By
comparison, the risk of schizophrenia in the general population
is only about 1 percent.
Scientists
are studying genetic factors in schizophrenia. It appears
likely that multiple genes are involved in creating a predisposition
to develop the disorder. In addition, factors such as prenatal
difficulties like intrauterine starvation or viral infections,
perinatal complications, and various nonspecific stressors,
seem to influence the development of schizophrenia. However,
it is not yet understood how the genetic predisposition is
transmitted, and it cannot yet be accurately predicted whether
a given person will or will not develop the disorder.
Is Schizophrenia Associated With
a Chemical Imbalance in the Brain?
Basic knowledge about brain chemistry and its link
to schizophrenia is expanding rapidly. Neurotransmitters,
substances that allow communication between nerve cells, have
long been thought to be involved in the development of schizophrenia.
It is likely, although not yet certain, that the disorder
is associated with some imbalance of the complex, interrelated
chemical systems of the brain, perhaps involving the neurotransmitters
dopamine and glutamate. This area of research is promising.
Is
Schizophrenia Caused by a Physical Abnormality in the Brain?
Many
studies of people with schizophrenia have found abnormalities
in brain structure. It should be emphasized that these abnormalities
are quite subtle and are not characteristic of all people
with schizophrenia, nor do they occur only in individuals
with this illness. Microscopic studies of brain tissue after
death have also shown small changes in distribution or number
of brain cells in people with schizophrenia. It appears that
many (but probably not all) of these changes are present before
an individual becomes ill, and schizophrenia may be, in part,
a disorder in development of the brain. Developmental
neurobiologists funded by the National Institute of Mental
Health (NIMH) have found that schizophrenia may be a developmental
disorder resulting when neurons form inappropriate connections
during fetal development. These errors may lie dormant until
puberty, when changes in the brain that occur normally during
this critical stage of maturation interact adversely with
the faulty connections. This research has spurred efforts
to identify prenatal factors that may have some bearing on
the apparent developmental abnormality.
In other
studies, investigators using brain imaging techniques have
found evidence of early biochemical changes that may precede
the onset of disease symptoms, prompting examination of the
neural circuits that are most likely to be involved in producing
those symptoms. Scientists working at the molecular level,
meanwhile, are exploring the genetic basis for abnormalities
in brain development and in the neurotransmitter systems regulating
brain function.
Medications
for Shizophrenia
Antipsychotic
medications have been available since the mid-1950s. Medications
reduce the psychotic symptoms of schizophrenia and usually
allow the patient to function more effectively and appropriately.
Antipsychotic drugs are the best treatment now available,
but they do not “cure” schizophrenia or ensure that
there will be no further psychotic episodes. The choice and
dosage of medication can be made only by a qualified physician
who is well trained in the medical treatment of mental disorders.
The dosage of medication is individualized for each patient,
since people may vary a great deal in the amount of drug needed
to reduce symptoms without producing troublesome side effects.
The large
majority of people with schizophrenia show substantial improvement
when treated with antipsychotic drugs. Some patients, however,
are not helped very much by the medications and a few do not
seem to need them. It is difficult to predict which patients
will fall into these two groups and to distinguish them from
the large majority of patients who do benefit from treatment
with antipsychotic drugs.
A number
of new antipsychotic drugs (the so-called “atypical antipsychotics”)
have been introduced since 1990. The newer antipsychotic drugs,
such as risperidone (Risperdal®) and olanzapine (Zyprexa®),
are safer than the older drugs, and they also may be better
tolerated.
Antipsychotic
drugs are often very effective in treating certain symptoms
of schizophrenia, particularly hallucinations and delusions;
unfortunately, the drugs may not be as helpful with other
symptoms, such as reduced motivation and emotional expressiveness.
Indeed, the older antipsychotics (which also went by the name
of “neuroleptics”), medicines like haloperidol (Haldol®)
or chlorpromazine (Thorazine®), may even produce side
effects that resemble the more difficult to treat symptoms.
Often, lowering the dose or switching to a different medicine
may reduce these side effects; the newer medicines, including
olanzapine (Zyprexa®), quetiapine (Seroquel®), and
risperidone (Risperdal®), appear less likely to have this
problem. Sometimes when people with schizophrenia become depressed,
other symptoms can appear to worsen. The symptoms may improve
with the addition of an antidepressant medication.
Patients and families sometimes become worried about the antipsychotic
medications used to treat schizophrenia. In addition to concern
about side effects, they may worry that such drugs could lead
to addiction. However, antipsychotic medications do not produce
a “high” (euphoria) or addictive behavior in people
who take them.
Another
misconception about antipsychotic drugs is that they act as
a kind of mind control, or a “chemical straitjacket.”
Anti-psychotic drugs used at the appropriate dosage do not
“knock out” people or take away their free will.
While these medications can be sedating, and while this effect
can be useful when treatment is initiated particularly if
an individual is quite agitated, the utility of the drugs
is not due to sedation but to their ability to diminish the
hallucinations, agitation, confusion, and delusions of a psychotic
episode. Thus, antipsychotic medications should eventually
help an individual with schizophrenia to deal with the world
more rationally.
The Outlook for Those Living with Schizophrenia
The outlook
for people with schizophrenia has improved over the last 25
years. Although no totally effective therapy has yet been
devised, it is important to remember that many people with
the illness improve enough to lead independent, satisfying
lives. As we learn more about the causes and treatments of
schizophrenia, we should be able to help more patients achieve
successful outcomes.
Studies
that have followed people with schizophrenia for long periods,
from the first episode to old age, reveal that a wide range
of outcomes is possible. When large groups of patients are
studied, certain factors tend to be associated with a better
outcome—for example, a pre-illness history of normal
social, school, and work adjustment. However, the current
state of knowledge does not allow for a sufficiently accurate
prediction of long-term outcome.
Given
the complexity of schizophrenia, the major questions about
this disorder—its cause or causes, prevention, and treatment—must
be addressed with research. The public should beware of those
offering "the cure" for (or "the cause"
of) schizophrenia. Such claims can provoke unrealistic expectations
that, when unfulfilled, lead to further disappointment. Although
progress has been made toward better understanding and treatment
of schizophrenia, continued investigation is urgently needed.
As the lead Federal agency for research on mental disorders,
the National Institute on Mental Health (NIMH) conducts and
supports a broad spectrum of mental illness research from
molecular genetics to large-scale epidemiologic studies of
populations. It is thought that this wide-ranging research
effort, including basic studies on the brain, will continue
to illuminate processes and principles important for understanding
the causes of schizophrenia and for developing more effective
treatments.
(Thanks are extended to the National Institute of Mental
Health for the information provided here).
