schizophrenia

• schizophrenia

  a severe mental illness where contact with reality and insight are impaired, PSYCHOSIS
• positive symptoms

  additional experiences onto typical behaviours

  hallucinations, delusions
• negative symptoms

  loss of usual activities/behaviours

  avolition, speech poverty
• IDC-10 diagnosis

  2+ negative symptoms
• DSM-5 diagnosis

  1+ positive symptom
• A03 - symptom overlap diagnosis

  schizophrenia and bipolar disorder involve positive symptoms like delusions and negative symptoms like avolition. This questions the validity of both classification and diagnosis of schizophrenia. Under ICD the patient might be diagnosed schizophrenic however the DSM may give a bipolar diagnosis.
• A03 + reliability diagnosis

  Osorio et al (2019) investigated 180 individuals diagnosed with the DSM-5 and found that there was inter-rather reliability of +.97 and test-retest of +.92. This shows that the diagnosis has good reliability. Inter-rater = two or more mental health professionals have the same diagnosis for the same patient. Test-retest = the same professional reaches the same diagnosis multiple occasions.
• A03 – validity diagnosis

  Chineaux et al (2009) found that more people were diagnosed with the ICD (68) than the DSM (39). This suggests either over diagnosis or under diagnosis.
• A03 – comorbidity diagnosis

  Schizophrenia is often occurring alongside another mental illnesses. Buckley et al (2009) said that 50% with schizophrenia had depression, 47% with schizophrenia had substance abuse and 23% with schizophrenia had OCD. This leads to questioning of which to priorities treatment and if the treatments will clash. 
• A03 – gender bias diagnosis

  Men are often diagnosed more than women with schizophrenia. This may be due to a genetic vulnerability or due to women being better at masking their symptoms. Cotton et al suggested that because women have close family relationships and continue to work, their symptoms are worse. The under diagnosis means that women may not get the treatment they require.
• A03 – cultural bias diagnosis

  Symptoms of schizophrenia, such as hearing voices, are accepted in certain cultures such as African and the West Indies as messages from ancestors. Due to this bias, it has been found that British people of African-Caribbean origin are 9x likely to be diagnosed with schizophrenia than white British people. 
• family studies

  risk of schizophrenia increases with genetic similarity
• Gottesmann (1991)

  the closer you are genetically, the more likely you are to develop schizophrenia

   - 48% identical twins

   - 17% fraternal twins

   - 2% cousins and uncles/aunts

   - 5% grandchildren  
• Ripke et al

  meta analysis

  indetified 108 separate genetic variations
• mutation

  in parental DNA caused by radiation, mutation, poison or viral infection can lead to schizophrenia in child
• brown et al, mutation

  positive correlations between paternal age and risk of schizophrenia 

  fathers under 25 = 0.7%

  fathers over 50 = 2%
• A03 - genetic support

  Tieneri et al - adoption studies. Children of schizophrenic parents are likely to get it even when adopted into families with no history of schizophrenia 
• A03 - environmental factors

  both biological and environmental factors

  biological - birth complications and THC-rich cannabis smoking in teenage years

  psychological - childhood trauma 

  67% of people with schizophrenia had at least 1 childhood trauma as opposed to 38% of a matched group with non psychotic mental health issues 

  genetic is not a complete explanation 
• A03 - genetic counselling

  genetic counselling. Parents who have or people who are related to schizophrenic people may choose to have genetic counselling to see the likelihood of the child developing it. However, the risk isn't a definite so it may lead to high levels of stress, miscarriage or unnessecary abortions 
• neural correlates

  brain structure or function

  dopamine
• original dopamine hypothesis

  based on the discovery that antipsychotic drugs used to treat schizophrenia cause similar symptoms to those of Parkinson's disease (a disease linked to low levels of DA).

  This concluded that schizophrenia was due to high levels of DA - hyperdopaminergia in subcortical areas of the brain.
• what does original dopamine hypothesis says caused schizophrenia

  high levels of DA (hyperdopaminergia) likely in Broca's area
• new dopamine hypothesis

  low levels DA (hypodopaminergia) in the prefrontal cortex
• Goldman-Rakic et al hypodopaminergia

  identified a role for low levels of dopamine in the prefrontal cortex (thinking and decision making) in the negative symptoms of schizophrenia.
• A03 - curren et al dopamine

  evidence for dopamine. Curren et al (2004) said that dopamine agonists like amphetamines (increase DA) make schizophrenia worse and can produce psychosis in non-sufferers. HOWEVER – there is some evidence that suggests dopamine is not a complete explanation because other neurotransmitters may have some influence.
• A03 - post mortem in neural correlates

  Post mortems and brain scans have consistently found low levels of glutamate in schizophrenic patients. Several candidate genes are thought to be responsible for glutamate production/processing. 
• A03 - tenn et al, rats and garson

   

  + Tenn et al (2003) induced schizophrenia-like symptoms in rats using amphetamines then relived symptoms using drugs that reduce DA action. HOWEVER – other drugs that increase DA do not cause schizophrenia like symptoms. Garson (2017) challenged the idea that amphetamine psychosis closely mimics schizophrenia 
• When were typical antipsychotics developed?

  In the 1950s
• What is the maximum daily dosage of Chlorpromazine when taken orally?

  Up to 1000mg daily
• How does Chlorpromazine function in the brain?

  It acts as a dopamine antagonist
• What happens to dopamine levels when Chlorpromazine is first administered?

  Dopamine levels initially build up
• What symptoms does Chlorpromazine help reduce?

  Symptoms like hallucinations
• What additional effect does Chlorpromazine have besides being an antipsychotic?

  It can act as a sedative
• Why is Chlorpromazine prescribed less frequently now?

  Due to the risk of side effects
• When were atypical antipsychotics developed?

  In the 1970s
• How does Clozapine differ from Chlorpromazine in its action?

  It also acts on serotonin and glutamate receptors
• What serious side effect led to the withdrawal of Clozapine?

  Agranulocytosis
• What is the typical dosage range for Clozapine?

  400mg-800mg
• What additional benefits does Clozapine provide?

  It may improve mood and cognitive function
• How does Risperidone compare to Clozapine?

  It is stronger and has a lower dose