Updated in September 2009
Fact Sheet content was reviewed by a member of NARSAD's Scientific Council
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Overview
Schizophrenia is a severe and debilitating brain disorder affecting how
one thinks, feels and acts. People with schizophrenia can have trouble
distinguishing reality from fantasy, expressing and managing normal
emotions and making decisions. Thought processes may also be
disorganized and the motivation to engage in life's activities may be
blunted. Those with the condition may hear imaginary voices and believe
others are reading their minds, controlling their thoughts or plotting
to harm them.
Schizophrenia affects approximately 1 percent of the world's
population over age 18 -- nearly 2.5 million people in the United
States. Symptoms usually first appear in men in their late teens and
early 20s and in women four to five years later. The disease can begin
after age 45 and before puberty, but is less likely to do so.
Most people with schizophrenia suffer from symptoms either continuously
or intermittently throughout life and are often severely stigmatized by
people who do not understand the disease. Contrary to popular
perception, people with schizophrenia do not have "split" or multiple
personalities, and most pose no danger to others. However, the symptoms
are terrifying to those afflicted and can make them unresponsive,
agitated or withdrawn. People with schizophrenia attempt suicide more
often than people in the general population, and estimates are that up
to 10 percent of people with schizophrenia will complete a suicide in
the first 10 years of the illness-particularly young men with
schizophrenia.
While schizophrenia is a chronic disorder, it can be treated with
medication, psychological and social treatments, substantially
improving the lives of people with the condition. Scientists are
working to understand the genetic and environmental mechanisms that
combine to cause schizophrenia. As they learn more about the chemical
circuitry and structure of the brains of people with the disease, they
are developing better ways to diagnose schizophrenia early on and
provide earlier interventions and treatments.
What are the symptoms of schizophrenia?
Schizophrenia is what physicians call a heterogeneous condition: it can
have very different symptoms in different people. The way the disease
manifests itself and progresses in a person depends on the time of
onset, severity, and duration of symptoms, which are categorized as
positive, negative and cognitive. "Positive" symptoms are active
symptoms, such as hallucinations, that people without psychosis don't
have, while "negative" symptoms reflect a loss of functioning in areas
such as emotion or motivation; and "cognitive" symptoms affect thinking
and higher brain functions. All three kinds of symptoms reflect
problems in the functioning of the brain. Relapse and remission cycles
often occur; a person can get better, worse, and better again
repeatedly over time.
• Positive symptoms, which can be severe or mild, include delusions,
hallucinations, and thought disorders. Some psychiatrists also include
psychomotor problems that affect movement in this category. Delusions,
hallucinations and inner voices are collectively called psychosis,
which also can be a hallmark of other serious mental illnesses such as
bipolar disorder. Delusions lead people to believe others are
monitoring or threatening them, or reading their thoughts.
Hallucinations cause a patient to hear, see, feel or smell something
that is not there. Thought disorders may involve difficulty putting
cohesive thoughts together or making sense of speech. Psychomotor
problems may appear as clumsiness, unusual mannerisms or repetitive
actions, and in extreme cases, motionless rigidity held for extended
periods of time.
• Negative symptoms include loss or reduction in the ability to
initiate plans, speak, express emotion or find pleasure in life. They
include emotional flatness or lack of expression, diminished ability to
begin and sustain a planned activity, social withdrawal, and apathy.
These symptoms can be mistaken for laziness or depression.
• Cognitive symptoms involve problems with attention and memory,
especially in planning and organizing to achieve a goal. Cognitive
deficits are the most disabling for patients trying to lead a normal
life.
Schizophrenia has a number of subtypes:
• Paranoid schizophrenia - feelings of extreme suspicion, persecution or grandiosity, or a combination of these.
• Disorganized schizophrenia - incoherent thoughts, but not necessarily delusional.
• Catatonic schizophrenia - withdrawal, negative affect and isolation, and marked psychomotor disturbances.
• Residual schizophrenia - delusions or hallucinations may go away, but motivation or interest in life is gone.
• Schizoaffective disorder - symptoms of both schizophrenia and a major mood disorder, such as depression.
For most people, though, the symptoms may be quite variable and not fall into any particular subtype.
How is schizophrenia diagnosed?
Currently, schizophrenia is diagnosed by the presence of symptoms or
their precursors for a period of six months. Two or more symptoms, such
as hallucinations, delusions, disorganized speech and grossly
disorganized or catatonic behavior, must be significant and last for at
least one month. Only one symptom is required for diagnosis if
delusions are bizarre enough or if hallucinations consist either of a
voice constantly commenting on the person's behavior/ thoughts or two
or more voices "conversing." Social or occupational problems can also
be part of the diagnosis during the six-month period.
While the illness may develop abruptly or gradually, schizophrenia is
often difficult to diagnose. The person's behavioral problems may seem
mild at first even though family members and the individual sense
something is wrong. Research is now being done to find markers, such as
abnormal brain scans or blood chemicals, that can help detect early
disease and allow for quicker interventions.
New NARSAD-supported research to improve the diagnosis of schizophrenia includes:
• Identifying unique blood factors in schizophrenia that may lead to a test to detect schizophrenia as early as possible
• Understanding the relationship between marijuana use and the onset of psychosis in schizophrenia.
• Learning how abnormal decision-making processes may be an early sign of schizophrenia.
• Combining brain imaging and behavioral assessments to discover how
the brains of individuals with schizophrenia may be unable to filter
out information, a hallmark of the disease
How is schizophrenia treated?
While no cure exists for schizophrenia, it is treatable and
manageable with medication and psychotherapy, especially if diagnosed
early and treated continuously. Those with acute symptoms, such as
severe delusions or hallucinations, suicidal thoughts or the inability
to care for themselves, may require hospitalization. Antipsychotic
drugs are the primary medications to treat schizophrenia. They relieve
the positive symptoms through their impact on the brain's
neurotransmitter systems. Psychiatrists may also give antidepressants
if an individual with schizophrenia is depressed.
The first generation of antipsychotics, introduced in the 1950s, block
the neurotransmitter dopamine. While they help to control abnormal
thinking, they may also limit emotional expression, and cause muscle
slowing and stiffness. Dopamine receptor blockers include:
chlorpromazine (Thorazine); fluphenazine (Prolixin); haloperidol
(Haldol), thiothixene (Navane), trifluoperazine (Stelazine),
perphenazine (Trilafon) and thioridazine (Mellaril).
Side effects can include dry mouth, constipation, blurred vision,
drowsiness, sexual dysfunction, menstrual changes, significant weight
gain, restlessness, stiffness, tremors, muscle spasms and tardive
dyskinesia (repetitive, involuntary stereotypic movements that may be
irreversible).
Recently, the so-called atypical antipsychotics, which block both the
dopamine and serotonin neurotransmitters and act at other receptors,
too, have become available. They appear as effective as older
medications in reducing positive symptoms, but have different side
effect profiles. Atypicals include: risperidone (Risperdal), clozapine
(Clozaril), olanzapine (Zyprexa), quetiapine (Seroquel) and ziprasidone
(Geodon).
Atypical antipsychotics have a variable side effect profile because of
their multiple neurotransmitter receptor effects. They may cause
drowsiness or dizziness when first taken. Blurred vision, a rapid
heartbeat, menstrual problems, sensitivity to the sun or skin rashes
may also occur. Many of these side effects diminish after the first
days of treatment. Clozapine can lower the white blood cell count,
making some patients infection prone, and must be monitored with
regular laboratory tests. Atypical antipsychotics also can lead to
weight gain and increase the risk of developing diabetes and other
metabolic problems. Despite these problems, pharmacologic treatment is
usually essential for a person with schizophrenia, and antipsychotic
medication should not be discontinued without medical supervision.
Numerous studies have found psychosocial treatments -- various forms of
psychotherapy, behavioral therapy, counseling and occupational
therapies -- can help patients who have stabilized on antipsychotic
medications.
These approaches improve communication, motivation and self-care and
teach coping mechanisms so that individuals with schizophrenia may
attend school, go to work and socialize. Patients undergoing regular
psychosocial treatment comply better with medication and have fewer
relapses and hospitalizations. A positive relationship with a therapist
or a case manager also gives a patient a reliable source of information
about schizophrenia, as well as empathy, encouragement and hope.
Social networks and family member support are very helpful, too. The
"Recovery Movement" is a new trend in self-help that empowers people
with schizophrenia to focus on their strengths in spite of the
challenges of living with the condition.
New NARSAD-supported research on treating schizophrenia includes:
• Improving drugs to treat the onset of schizophrenia through
pharmacogenetics , an approach to understanding how people with
different genetic backgrounds respond to different drugs
• Understanding new, alternate neurotransmitter pathways in the brain,
including the GABA and glutamate systems, that may contribute to
schizophrenia, and how they could be affected by new drugs
• Figuring out why some individuals become less responsive to antipsychotic medications over time
• Developing drugs that target the cognitive symptoms of schizophrenia , which are not directly treated by antipsychotic drugs
• Measuring the effectiveness of an online cognitive behavioral program to help patients deal with auditory hallucinations
• Creating employment programs that help people with schizophrenia and
other mental illnesses improve cognitive skills, work and contribute to
society
• Developing ways to treat or prevent the weight gain and metabolic side effects that come with atypical antipsychotics
What causes schizophrenia?
Like other serious neuropsychiatric illnesses, schizophrenia is a
highly complex disease believed to result from many factors, including
genetic vulnerability, biological imbalances in the brain's chemistry
and even environmental events that occur during a person's development,
in some cases possibly during the prenatal period.
Studies of identical twins suggest schizophrenia runs in families.
Scientists have identified a number of gene variations that appear to
increase risk for the disorder. Deletions or amplification of certain
genes may also increase the risk of schizophrenia. Some epigenetic
changes, or genetic alterations that alter gene expression but do not
affect the sequence of genes, also have been linked to schizophrenia.
But scientists are still studying how these gene changes, alone or in
combination, cause illness.
Schizophrenia may also be related to other environmental factors, such
as viral infections, pre-natal malnutrition, perinatal problems, or a
combination of factors. Although psychological and other kinds of
stress have never been shown to cause schizophrenia, stress may play a
role in the timing and symptoms of the disease and in recovery from it.
For quite some time scientists focused on how abnormal levels of the
brain chemicals serotonin and dopamine, neurotransmitters that allow
nerve cells to communicate, may be related to schizophrenia. A
neurotransmitter imbalance affects the way the brain reacts to stimuli
(sights, smells, sounds, tastes), and may make someone with
schizophrenia overwhelmed by sensory information. Problems in
processing external stimuli can contribute to psychosis. Recent studies
have been examining how other neurotransmitters, such as glutamate and
GABA, or gamma-aminobutyric acid, act in schizophrenia.
Brain imaging technology has revealed differences in the brains of
people with schizophrenia compared to those who do not have the
disease. People with schizophrenia may have reduced numbers of nerve
cell connections (synapses) in some regions of the brain, and may have
abnormal levels or activity of brain neurotransmitters, such as GABA
and glutamate. These differences may not cause schizophrenia, but
scientists are actively investigating the disease process to be able to
design drugs or other treatments to overcome the problems.
New NARSAD-supported research to understand the causes of schizophrenia include:
• Combining brain imaging and genetic studies to understand what factors increase the risk of schizophrenia
• Studying the genes for neuregulin, dysbindin, DISC1 and other brain chemicals, that may contribute to schizophrenia
• Developing new methods, such as magnetic resonance imaging,
ultrasound and other approaches, for increasingly precise studies of
brain structure and function in schizophrenia
• Working with animal models to try to analyze how both genes and
environmental stresses, such as maternal infection or severe trauma in
early life, may lead to schizophrenia
• Studying the molecular biology of what goes wrong in schizophrenia at
the level of synapse, the point of connection between nerve cells in
the brain
• Understanding and treating what causes the debilitating cognitive problems of schizophrenia
Living with schizophrenia-from diagnosis to treatment
A diagnosis of schizophrenia may take a period of time, since symptoms
usually need to be observed over a six month period. Psychiatrists need
to rule out other medical conditions, such as epilepsy, bipolar
disorder, a brain tumor, steroid overdose, and substance abuse, all of
which can cause psychosis that may initially look similar to
schizophrenia. For some time, before a psychotic episode emerges,
family members, co-workers and the patient might be worried about
unusual behavior-loss of friends, poor grades in school, trouble
trusting people, or odd ways of communicating. A young or older person
hearing voices or hallucinating may be afraid to tell parents or
doctors about their experiences, and the condition will go unnoticed
until the person reveals what is happening inside his or her head or
until disorganized thought becomes so obvious that medical care is
warranted. In some cases, a psychotic episode or suicide attempt may
bring the individual in contact with the police or to an emergency
room. People who are a danger to themselves or others or cannot take
care of themselves may need to be hospitalized.
For some, a diagnosis of schizophrenia can be a relief, because it
helps explain what has been so wrong. For others, it is devastating. In
either case, a doctor can start right away to educate the patient and
loved ones about the condition, start antipsychotic treatment and help
the person with schizophrenia cope with their own unique form of the
disease. Each individual and family has to learn how to improve what is
good and how to respond to possible recurrences or worsening of
psychosis. It can be difficult to stay on antipsychotic medications
because of their side effects, but it's critically important in
recovery. Different drugs are available and new ones can always be
tried to find the greatest benefit with the fewest side effects. There
is some evidence that the prognosis is best when schizophrenia is
identified early, when an individual is still socially engaged with
school or work and the brain hasn't suffered the biological effects of
the disease. But continual care, such as psychosocial treatment to
learn how to deal with stressors that might increase the risk of
psychoses, is helpful even for people who are diagnosed later on. New
drug-based and psychological interventions are on the horizon and offer
hope for people with this illness and their families.
How is NARSAD helping people with schizophrenia?
For the past 23 years, NARSAD has been at the forefront of
schizophrenia research. It is second only to the National Institute of
Mental Health in dollars given to research into causes, prevention and
improved treatments for the illness. To date, NARSAD has provided:
• 1,706 grants to researchers studying schizophrenia and related psychotic disorders
• $111 million dollars for those research grants
NARSAD supports work in all the major areas of schizophrenia
research-the causes and nature of the disease, structural and
functional changes in the brain, chemical abnormalities, genetics,
pharmacological and non-pharmacological treatments, and social and
behavioral problems associated with the illness.
Besides schizophrenia research, NARSAD funds research on depression,
bipolar disorder, anxiety, and childhood mental illness. NARSAD's
grants programs are guided by its Scientific Council, a volunteer group
comprised of 116 leading neuroscientists, which reviews and recommends
research proposals for funding.
NARSAD relies on thousands of donors and volunteers to support the
research, which has yielded great progress in the understanding,
diagnosis and treatment of mental illnesses. To keep its donors and the
general public informed about progress, NARSAD has a website
(www.narsad.org), produces publications and presents nationwide public
symposia, where NARSAD scientists share their research developments.
Formerly known as the National Alliance for Research on
Schizophrenia and Depression, NARSAD is a 501 (c)(3) organization that
receives no government support; all donations are tax-deductible. To
donate to NARSAD and for more information, click here.