Schizophrenia

Schizophrenia is a mental disorder characterized by a breakdown of thought processes and by poor emotional responsiveness.  It is a psychotic disorder characterized by loss of contact with the environment, by noticeable decline in the level of functioning in everyday life, and by collapsing of personality expressed as disorder of feeling, thought (as delusions), perception (as hallucinations), and behavior .

The disorder is thought mainly to affect cognition, but it also usually contributes to chronic problems with behavior and emotion. People with schizophrenia are likely to have additional conditions, including major depression and anxiety disorders; the lifetime occurrence of substance abuse is almost 50%. Social problems, such as long-term unemployment, poverty and homelessness, are common. The average life expectancy of people with the disorder is 12 to 15 years less than those without, the result of increased physical health problems and a higher suicide rate .

Symptoms:

First-rank symptoms by Kurt Schneider in schizophrenia

§  Audible thoughts (thought echo)

§  Voices heard arguing

§  Voices heard commenting on one's actions

§  Somatic/thought passivity experiences (delusions of control)

§  Thought withdrawal

§  Thought insertion - Thoughts are ascribed to other people who intrude their thoughts upon the patient

§  Thought broadcasting (also called thought diffusion)

§  Delusional perception (i.e. taking a normal sensory perception to mean a bizarre situation such as taking seeing an aeroplane as indicating the patient should be the next president).

Other symptoms includes :

·          Hallucinations (most reported are hearing voices), 

·         delusions (often bizarre or persecutory in nature), and 

·         disorganized thinking and speech.

·         Impairment in social cognition is associated with schizophrenia, as are symptoms of paranoia; social isolation commonly occurs.

·         Difficulties in working and long-term memory, attention, executive functioning, and speed of processing also commonly occur.

The latter may range from loss of train of thought, to sentences only loosely connected in meaning, to incoherence known as word salad in severe cases. Social withdrawal, sloppiness of dress and hygiene, and loss of motivation and judgment are all common in schizophrenia. There is often an observable pattern of emotional difficulty, for example lack of

responsiveness.  In one uncommon subtype, the person may be largely mute, remain motionless in bizarre postures, or exhibit purposeless agitation, all signs of catatonia.

Schizophrenia is often described in terms of positive and negative (or deficit) symptoms. Positive symptoms are those that most individuals do not normally experience but are present in people with schizophrenia.

Positive Symptoms:

They can include

·         delusions,

·         disordered thoughts and speech,

·         and tactile, auditory, visual, olfactory and gustatory hallucinations,Typically regarded as manifestations of psychosis.

Hallucinations are also typically related to the content of the delusional theme. Positive symptoms generally respond well to medication.

Negative symptoms

They are deficits of normal emotional responses or of other thought processes, and respond less well to medication.

·         They commonly include flat or blunted affect and emotion,

·         poverty of speech (alogia),

·         inability to experience pleasure (anhedonia),

·         lack of desire to form relationships (asociality),

·         and lack of motivation (avolition).

Research suggests that negative symptoms contribute more to poor quality of life, functional disability, and the burden on others than do positive symptoms. People with prominent negative symptoms often have a history of poor adjustment before the onset of illness, and response to medication is often limited.

Causes:

No single cause can account for schizophrenia. Rather, it appears to be the result of multiple causes such as genetic factors, environmental and psychological assaults, and possible hormonal changes that alter the brain's chemistry.

Abnormalities in Brain Structure, Circuitry, and Chemicals

Brain scans using magnetic resonance imaging (MRI) have shown a number of abnormalities in the brain's structure associated with schizophrenia. Such problems can cause nerve damage and disconnections in the pathways that carry brain chemicals.

Because these problems tend to show up on brain scans of people with chronic schizophrenia rather than newly diagnosed patients, some doctors believe they may be a result of the disease and its treatments rather than a cause. (Medications used for schizophrenia can also cause brain shrinkage over time.)

Abnormal Brain Chemicals. Schizophrenia is associated with an unusual imbalance of neurotransmitters (chemical messengers between nerve cells) and other brain chemicals, such as dopamine overactivity, glutamate, reelin, and others. Whether any changes in these chemicals in the brain is a cause or a consequence of schizophrenia remains unclear.

Abnormal Circuitry. Abnormalities in brain structure are also reflected in the disrupted connections between nerve cells that are observed in schizophrenia. Such miswiring could impair information processing and coordination of mental functions. For example, auditory hallucinations may be due to miswiring in the circuits that govern speech processing. Strong evidence suggests that schizophrenia involves decreased communication between the left and right sides of the brain.

Genetic Factors

Schizophrenia undoubtedly has a genetic component. The risk for inheriting schizophrenia is 10% in those who have one immediate family member with the disease and about 40% if the disease affects both parents or an identical twin. Family members of patients also appear to have higher risks for the specific symptoms (negative or positive) of the relative with schizophrenia.

Researchers are seeking the specific genetic factors that may be responsible for schizophrenia in such cases. Current evidence suggests that there are a multitude of genetic abnormalities involved in schizophrenia, possibly originating from one or two changes in genetic expression. Scientists are beginning to discover the ways in which specific genes affect particular brain functions and cause specific symptoms. Genes that have been studied include the neuregulin-1 gene, the OLIG2 gene, and the COMT gene.

Heredity does not explain all cases of the disease. About 60% of people with schizophrenia have no close relatives with the illness.

Infectious Factors

The case for viruses as a cause of schizophrenia rests mainly on circumstantial evidence, such as living in crowded conditions. The risk is higher for people who are born in cities than in the country. The longer one lives in the city, the higher the risk. The following are some studies suggesting an association:

• Winter and Spring Births. The risk for schizophrenia worldwide is 5 - 8% higher for those born during winter and spring, when colds and viruses are more prevalent.
• Large Families. The risk for schizophrenia is also greater in large families in which there are short intervals between siblings (2 or fewer years). Such observations suggest that exposure to infection early in infancy may help set the stage for later development of the disease.
• Pregnant Mother's Exposure to Viruses. The mother's exposure to viral infections such as rubella, measles, chicken pox, or others while the infant is in the womb has also been associated with a higher risk for schizophrenia in her child.
• Researchers are trying to identify specific viruses that may be responsible for some cases. Of particular interest is research finding evidence of a virus that belongs to the HERV-W retrovirus family in 30% of people with acute schizophrenia.

Some research has found an association between some cases of schizophrenia and toxoplasmosis, a parasite carried by cats and other domestic animals. Several studies suggest that patients with schizophrenia have an increased prevalence of antibodies to toxoplasmosis. Toxoplasmosis can lie dormant in the nervous system and migrate to the brain over many years.

Psychological Factors

Although parental influence is no longer believed to play a major role in the development of schizophrenia, it would be irresponsible to ignore outside pressures and influences that may exacerbate or trigger symptoms. The prefrontal lobes of the brain, the brain areas often thought to lead to this disease, are extremely responsive to environmental stress. Given the fact that schizophrenic symptoms naturally elicit negative responses from the patient's circle of family and acquaintances, negative feedback may intensify deficits in a vulnerable brain and perhaps even trigger and exacerbate existing symptoms.

Types of Schizophrenia:

The DSM-IV-TR contains five sub-classifications of schizophrenia, although the developers of DSM-5 are recommending they be dropped from the new classification.

§  Paranoid type: Delusions or auditory hallucinations are present, but thought disorder, disorganized behavior, or affective flattening are not. Delusions are persecutory and/or grandiose, but in addition to these, other themes such as jealousy, religiosity, or somatization may also be present. (DSM code 295.3/ICD code F20.0)

§  Disorganized type: Named hebephrenic schizophrenia in the ICD. Where thought disorder and flat affect are present together. (DSM code 295.1/ICD code F20.1)

§  Catatonic type: The subject may be almost immobile or exhibit agitated purposeless movement. Symptoms can include catatonic stupor and waxy flexibility. (DSM code 295.2/ICD code F20.2)

§  Undifferentiated type: Psychotic symptoms are present but the criteria for paranoid, disorganized, or catatonic types have not been met. (DSM code 295.9/ICD code F20.3)

§  Residual type: Where positive symptoms are present at a low intensity only. (DSM code 295.6/ICD code F20.5)

§   

The ICD-10 defines two additional subtypes:

§  Post-schizophrenic depression: A depressive episode arising in the aftermath of a schizophrenic illness where some low-level schizophrenic symptoms may still be present. (ICD code F20.4)

§  Simple schizophrenia: Insidious and progressive development of prominent negative symptoms with no history of psychotic episodes. (ICD code F20.6).

Treatment:

Medication:

The first-line psychiatric treatment for schizophrenia is antipsychotic medication, which can reduce the positive symptoms of psychosis in about 7–14 days. Antipsychotics, however, fail to significantly ameliorate the negative symptoms and cognitive dysfunction. Long term use decreases the risk of relapse.

Therapy for Schizophrenia

Through therapy, people can develop social and work skills to improve their lives and relationships.A number of psychosocial interventions may be useful in the treatment of schizophrenia including: family therapy, assertive community treatment, supported employment, cognitive remediation, skills training, cognitive behavioral therapy (CBT), token economic interventions, and psychosocial interventions for substance use and weight management. Family therapy or education, which addresses the whole family system of an individual, may reduce relapses and hospitalizations. The evidence for CBT's effectiveness in either reducing symptoms or preventing relapse is minimal.^[ Art or drama therapy have not been well-researched.

Electroconvulsive Therapy and Schizophrenia

ECT is often misunderstood, but it’s highly effective for certain types of schizophrenia.