What are the facts of Schizophrenia?
- Schizophrenia is a chronic, severe brain disorder. It is considered to be one of the most disabling of the serious mental illnesses.
- Schizophrenia is associated with both positive symptoms (e.g., delusions, hallucinations, disorganized thinking and behavior, catatonic movements) and negative symptoms (e.g., affective flattening, alogia, and avolition).
- In any given year, 2.2 million adults in the US about 1.1% of the population age 18 and over have schizophrenia. The rates of schizophrenia are similar worldwide.
- Although two-thirds of treated patients require hospitalization, only about half of all people with schizophrenia receive treatment.
- Schizophrenia has been recognized in one form or another throughout recorded history.
- Misleading terms that are often incorrectly associated with schizophrenia include multiple personality, psychopath, and sociopath.
- The premorbid phase refers to the period before a person first shows clear symptoms of schizophrenia. In retrospect, family members may recall that the person was “a little unusual” or “different.”
- The prodromal phase is the earliest presentation of schizophrenia; the person begins to experience distinct changes in perception or thinking, without overt psychosis. Characteristic behaviors may include social withdrawal, reduced concentration or motivation, suspiciousness, peculiar speech, and an interest in abstract ideas, philosophy, the occult, or religion.
- The onset phase (first break) is when the symptoms of psychosis are first clearly noticed. It is usually characterized by positive symptoms (e.g., hallucinations, delusions, and disorganized thinking and behavior).
- The chronic phase is characterized by periodic relapses and remissions. Although some people may gradually recover from a psychotic episode and function with minimal impairment, in most cases the individual will eventually relapse.
- The positive symptoms of schizophrenia tend to become less severe over time. However, the socially debilitating negative symptoms may actually worsen.
- About half of people with schizophrenia attempt suicide at least once, and 10% to 15% die from suicide over a 20-year period.
- Schizophrenia often progressively worsens over time. Relapses may become more severe over time, and the time between relapses often decreases with each new psychotic episode.
- Changes in the brain may occur as patients enter the chronic phase. This may mean that the longer a patient experiences psychosis without initial treatment, the worse the treatment response and outcome.
- Some researchers now postulate that psychosis is an active disease process that if not treated could lead to treatment resistance.
- Genetic and biological/environmental factors are believed to be most important in causing schizophrenia, while psychosocial factors may be more important in affecting the onset and course of the disease.
- Some evidence suggests that schizophrenia has a genetic component. For example, people with one affected first-degree relative have a 10% increased risk for developing schizophrenia; children with two affected parents have a 40% increased risk.
- When one identical twin has schizophrenia, the second twin does not have a 100% chance of being affected. This means the development of schizophrenia cannot be solely attributed to genetic factors.
- Biological/environmental factors that may increase the risk of developing schizophrenia include complications during gestation or birth and viral infections.
- Psychoanalytic, psychodynamic, and learning theories suggest that psychosocial factors can cause schizophrenia, but these theories are not commonly believed today.
- In people with schizophrenia, components of the limbic system are often decreased in size, whereas the volume of basal ganglia nuclei may be increased.
- Both MRI and CT studies have found that patients with schizophrenia have enlarged ventricles.
- Some PET scans have found that people with schizophrenia have hypoactivity in the frontal lobes and hyperactivity in the basal ganglia, but these results have not been widely replicated.
- The initial dopamine hypothesis stated that in schizophrenia, certain regions of the brain produce excess dopamine, thereby causing symptoms of the disease, particularly positive symptoms. The theory has since been expanded to propose that decreased dopaminergic activity may also be a factor.
- Hyperactivity of the mesolimbic dopaminergic pathways may cause the positive symptoms of schizophrenia, while deficits in the mesocortical dopamine pathway may cause the negative symptoms and some cognitive deficits of schizophrenia.
- Dopamine deficiencies in the nigrostriatal pathway (e.g., due to blockade of D2 receptors by antipsychotic drugs) may cause extrapyramidal symptoms (EPS) such as akathisia, dystonia, and akinesia.
- D2 blockade and the resultant dopamine deficiencies in the tuberoinfundibular pathway can result in hyperprolactinemia.
- Evidence for the role of serotonin in schizophrenia includes the fact that atypical antipsychotics, which block 5-HT2A receptors, increase serotonin and dopamine levels, and that in the prefrontal cortex these effects are associated with improved cognition.
- Other neurotransmitters and receptors that may be involved in schizophrenia include norepinephrine, glutamate, NMDA receptors, GABA, histamine, and acetylcholine. However, their role is not well understood.
- Neurologic signs are seen in many people with schizophrenia and are important because they may indicate the severity of illness and poor prognosis. Neurologic signs may also be the result of the medication. They include nonlocalized signs (e.g., clumsiness and primitive reflexes) and other signs such as tics, grimacing, and impaired fine motor skills.
- Because schizophrenia is a syndrome, different people diagnosed with the illness can have different symptoms. It is also a heterogeneous disease.
- No single symptom of schizophrenia is pathognomonic, but the occurrence of several symptoms can be diagnostic of the disease.
- The positive symptoms of schizophrenia reflect an excess or distortion of normal functioning. They include delusions, hallucinations, disorganized thinking and behavior, and catatonic motor behaviors.
- Delusions are erroneous beliefs that involve misinterpretation of perceptions or experiences and that a person strongly believes despite obvious evidence to the contrary. In schizophrenia, the most common type are persecutory delusions.
- Hallucinations are sensory impressions that occur without any external stimulation. Auditory hallucinations (e.g., hearing voices) are most commonly seen in schizophrenia.
- Disorganized thinking is considered by some to be the most important feature of schizophrenia. The most common forms are derailment (loose associations) and tangentiality (answering questions with unclear or unrelated responses).
- Disorganized behavior may range from childlike silliness to unpredictable agitation. Other expressions of this symptom may include disheveled or unusual dress, inappropriate sexual behavior, and unexplained agitation.
- Catatonic motor behavior refers to a decrease in reactivity to the environment. This behavior occurs when patients are overwhelmed by environmental stimuli and are unable to differentiate or filter out the overload of sensory information. It may include complete unawareness (catatonic stupor), maintaining a rigid posture (catatonic rigidity), and holding unusual or bizarre postures.
- The negative symptoms of schizophrenia reflect a loss of normal functioning. They include affective flattening, alogia, avolition, and anhedonia.
- Affective flattening is a common negative symptom that frequently manifests as an unchanging facial expression, lack of vocal inflections, and poor eye contact.
- Alogia (poverty of speech) is also common in schizophrenia, seen as a poverty or lack of speech, brief or empty replies to questions, or a lengthy delay before responding in conversation.
- Avolition (apathy) is a lack of motivation and an inability to initiate activities or pursue goals. Patients may simply sit for long periods with little interest in work or social activities.
- Anhedonia is a loss of enjoyment in activities that were previously pleasurable. Areas commonly affected include recreational activities, relationships, intimacy, and sexual activity. Other key symptoms of schizophrenia include social/personal dysfunction and cognitive deficits.
- Schizophrenia is a diagnosis of exclusion; a definitive diagnosis may not be made until other explanations for the symptoms have been ruled out.
- In general, diagnosing schizophrenia involves 1) ruling out organic causes; 2) ruling out other psychiatric disorders; and 3) identifying the specific subtype of schizophrenia involved.
- The Mental Status Examination can help in identifying certain features of schizophrenia. Relevant categories include general description; mood, feelings, and affect; perceptual disturbances; thought; impulsiveness and violence; orientation; and judgment and insight.
- To make a diagnosis of schizophrenia using the DSM-IV-TR, six criteria must be met. Criterion A states that patients must have at least two of five major symptoms: delusions, hallucinations, disorganized speech, grossly disorganized or catatonic behavior, negative symptoms.
- Criterion B states that one or more major areas of functioning must be markedly impaired for a significant portion of time since the illness began. Criterion C states that continuous signs of the disturbance must persist for at least 6 months.
- Criteria D, E, and F require that schizoaffective disorder and mood disorder (as well as other causes of psychosis, including substances, underlying medical conditions, and development disorders) be ruled out.
- Schizophreniform disorder is identical to schizophrenia but has a duration of less than 6 months and the patient does not necessarily have impaired social or occupational functioning.
- Schizoaffective disorder is similar to schizophrenia, but the patient must also have a mood episode (major depressive episode, manic episode, or mixed episode) during a substantial portion of the illness, as well as delusions or hallucinations for at least 2 weeks without prominent mood symptoms. The DSM-IV-TR chapter on schizophrenia also describes disorders in which psychotic symptoms are a prominent feature. However, psychotic symptoms are not necessarily the core feature, and these disorders do not necessarily share a common etiology.
- Because there is no cure for schizophrenia, therapy generally focuses on achieving three basic goals: relieving symptoms, preventing relapse, and improving social and occupational functioning.
- Pharmacologic agents are a cornerstone in treating schizophrenia, but effective treatment often involves psychosocial therapy and rehabilitation as well.
- The BPRS and PANSS are often used to measure treatment response in clinical trials; a decrease of 20% or more is often used to indicate a response to treatment.
- At least 30% of patients with schizophrenia have an inadequate or poor response to typical antipsychotics. Side effects (especially EPS) associated with typical antipsychotics contribute to rates of treatment nonadherence that approach 50%.
- The benefits of short-term hospitalization during the acute phase of schizophrenia include providing an opportunity for diagnosis and treatment, and establishing a framework for long-term support. The average length of stay is 4 to 6 weeks.
- The goal of psychosocial therapy is to help resolve social and psychological difficulties. In addition, it can help improve treatment adherence and the capacity to handle stress, identify expectations for achievement, and provide support.
- Important forms of psychosocial therapy in schizophrenia include behavior therapy, family-oriented therapy, group therapy, cognitive therapy, and individual therapy.
- Rehabilitation services for people with schizophrenia include supervised shelters, social and occupational skills training, and lessons in daily hygiene and food preparation.
- Antipsychotic medications do not cure schizophrenia, but they can effectively treat many of the symptoms seen in schizophrenia. Compared with patients who receive antipsychotic medications, about two to four times as many patients who receive a placebo will relapse.
- Typical antipsychotics block D2 receptors in all dopaminergic pathways in the brain. The blockade of D2 receptors in the mesolimbic pathway is believed to relieve the positive symptoms of schizophrenia.
- Many side effects associated with typical antipsychotics may result from their blockade of D2 receptors in other dopaminergic pathways.
- Atypical antipsychotics block both serotonin (5-HT2A ) and dopamine (D2) receptors.
- When atypical antipsychotics block 5-HT2A receptors, they increase dopamine release, which may counteract their D2-blocking properties. This decreases side effects caused by D2 antagonism in the nigrostriatal and tuberoinfundibular pathways. In the mesocortical pathway, these effects may improve negative symptoms.
- Good prognostic indicators of treatment outcome include late or acute onset, being married, positive symptoms, and few or no relapses. Poor indicators include early onset; being single, divorced, or widowed; negative symptoms; and many relapses.
- Psychosis is a state of mind that can occur in a number of psychiatric disorders and medical conditions. During psychosis, the individual’s ability to recognize reality, communicate, and relate to others is severely impaired.
- Psychosis can be caused by medical conditions (e.g., epilepsy, tumors, AIDS, trauma), use of/withdrawal from substances (e.g., amphetamines, hallucinogens, alcohol), or psychiatric disorders (e.g., schizophrenia, bipolar disorder). In discussing psychiatric causes of psychosis, the DSM-IV-TR notes that psychosis can be narrowly defined as delusions or prominent hallucinations. A broader definition includes positive symptoms, but not negative symptoms.
Schizophrenia |
History of Schizophrenia |
Schizophrenia Syndrome |
Schizophrenia Misconceptions |
Epidemiology of Schizophrenia |
Facts of Schizophrenia |
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