Schizophrenia Revision (Diagnosis, Aetiology, Treatments)

• Schneider (1959) - criteria for diagnosing schizophrenia --> positive and negative symptoms.

1) Positive Symptoms

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  • Main diagnositc criteria
  • Excesses / Distortions (e.g. delusions and hallucinations)
  • Positive symptoms usually present in acute episodes.

2) Negative Symptoms

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  • Behavioural deficits --> tend to last beyond acute episodes into chronic episode.
  • Important prognostically - many negative symptoms = poor quality of life. 
  • Apathy, Alogia, Anhedonia, Asociality and Flat Affect 

3) Disorganised Symptoms

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  • Speech and behaviour - problems speaking so listener can understand/trouble making behaviour conform to everyday standards. 
• Catatonia = repeating gestures over and over/adopt unusual posture and maintain for long periods.
• Inappropriate Affect = emotional response out of context, e.g. laugh at hearing about a death. 
• 3 Stages - 1) Prodromal, 2) Active, 3) Residual

• Perala et al (2007) - 3.2% of population have schizophrenia

• Onset usually mid 20s/early 30s

• Onset rare after 45 years of age

• More common in men than women.

• Often begins after a prolonged period of stress

Family Studies

• Kendler et al (1996) - relatives of schizophrenics at risk, risk increases as genetic similarity increases. 
• Malaspina (2000)    - Family history of Sz = more negative symptoms = negative symptoms                                    may have stronger genetic component?
• Kender et al (1995) -  Relatives also at risk of related disorders e.g. schizotypal personality disorder.

Twin Studies

• Gottesman (1987) - higher concordance for MZ twins than DZ. 
• Gottesman (1981) - risk increases when Sz twin is more severely ill. 
• Canon et al (1998)- concordance not 100% so genetics can not be the sole influence. 

Adoption Studies

• Heston (1966) - control group = 0% had Sz; Sz mother group  16.6% had Sz. 
• BUT! - Birth mother and child shared environment for a limited period of time. 

• Based on the efficacy of drugs that reduce dopamine for treating schizophrenia.

• Suggests Sz may be caused by overactivity or elevated levels of dopamine. 

• Comer et al - stress = increased dopamine firing = delusions / hallucinations. 

Amphetamine Psychosis

• Amphetamines can produce a state similar to paranoid schizophrenia. 
• They cause increased release of dopamine and NA
• Further evidence for increased dopamine and schizophrenia link . 

• Wong et al (1986) - PET scan - higher dopamine in Sz patients than controls. 

• Glutamate, GABA and Serotonin may mediate dopamine <---> schizophrenia link. 

1) Enlarged Ventricles

• McNeil (2000) - Schizophrenia patients often found to have enlarged ventricles.

• This is not exclusive to schizophrenia

• Link not fully understood but seem to be related in some way.

2) Prefrontal Cortex (PFC) Dysfunction

• Prefrontal cortex responsible for a number of the things disrupted by schizophrenia. 

• Buchanan et al (1998) - reduced grey matter in PFC of schizophrenics. 

• Barch et al (2003/2003) - poor performance on tasks which utilise PFC.

• Barch et al (2001) reduced activation in PFC of schizophrenics.

• Attempts to explain behaviour as a predispositional vulnerability together with stress from life experiences.
• Diathesis = disposition or vulnerability. 
• Outlines the importance of both nature AND nurture in the development of psychopathology.

1) Diathesis (Vulnerability).

• Can be biological = genes/brain structure. 
• Can be social = chronic stress, poor social skills
• Can be psychological = unconscious conflicts, poor life skills. 

2) Stress

• Stressors = life events which can disrupt the equilibrium of a person's life and can be a specific event e.g. divorce/loss or could be from chronic factors such as long-term illness. 
• Can be biological = onset of disease / exposure to toxins. 
• Can be social = traumatic event
• Can be psychological = perceived loss of control. 

• DIATHESIS + STRESS = SCHIZOPHRENIA DISORDER

• Electric Shock Therapy (E.S.T.) 

• Literally "Shaking" the madness out of a person.
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• Cold baths - have a calming effect. 

• Trepanation - holes in skull to relieve pressure. 

• Blood letting - to let out badness in blood. 

• In the past people were confined to psychiatric unit and could not leave. 
• People did not have the choice/right to refuse treatment.
• Could past treatments and treatment of individuals be classed as inhumane?

1st Generation

• E.g. Thorazine, Haldol
• Able to reduce positive symptoms but had little effect on negative symptoms - partially effective
• Only had effects on dopamine (which is responsible for positive symptoms)
• Lieberman (2005) - Many dropped out of trials due to unwanted side effects.

2nd Generation

• Wahlbeck et al (1999) - Clozapine - improved positive and disorganised symptoms.
• Found to be effective at reducing relapse (Conley et al, 1999)
• BUT! - also found to reduce white blood cell count/immune function among other effects.

3rd Generation

• E.g. Zyprexa, Risperdal
• Dolder et al (2002) - As effective as 1st gen but less side effects and lower drop out rates.

MATRICS Project - developed to compare medications for treating certain individuals.

Battery of tests completed to assess Sz stageand most suitable medication chosen based on results.

• Despite unwanted side effects are an indispensible part of treatment. 

• Limited success of previous drugs has prompted development of new ones & promising new drugs are continually being trialled and evaluated.

• Medication is not a cure but can make symptoms a lot more manageable. 

• Hogarty et al (1974) - Use must be continued to avoid relapse.

• Most individuals are not fully compliant so the level of relapse is high. 

• Influenced by Beck and Ellis. 
• Person's beliefs / appraisals of a situation are faulty --> misattribution. 
• Must change faulty assumptions and thinking. 
• Challenge delusional thinking --> challenge evidence for beliefs and provide more realistic explanation. 

• A range of coping strategies have been developed:
• e.g. thought blocking (drowning out voices), relaxation techniques, testing faulty cognitions (delusions)

• Latest approach is coping strategy enhancement.
• Uses a range of cognitive-behavioural strategies at same time. 
• Turkington et al (2002) - Useful at minimising some symptoms but not all 

• Management / treatment of patients within a community setting. 
• Developed since closure of long-term institutes. 
• Assumption that if acute symptoms are treated vigorously then person can return to care of GP/community. 
• Reduces the need for long-term institutes & people can return and live with family. 
• Support is tailored to each individual - organised by nurse or small team. 
• Mueser et al (1998) - If needed, other services can be brought in to impove effectiveness. 

Efficacy

• Stein & Test (1980) - 89% relapse for inpatients compared to 18% for community care. 
• BUT! - gains steadily lost at end of program.
• Excellent idea and principle but not enough support services available. 
• Highlights the importance of treatment tailored to each individual and stage of illness. 

1) Non-Compliance

• Julien (2008) - Conventional antipsychotics (1st Gen) = 65% compliance.
• Julien (2008) - Atypical (2nd/3rd Gen) = 85% compliance.
• Comer (2010) - 2nd/3rd Gen able to treat some negative symptoms but also have many negative effects.
• Low compliance = poor prognosis and increased chance of relapse.
• Moritz et al (2009) Full compliance is linked to fewer psychotic symptoms & side effects.

2) Social Factors

• Disorder strongly affected by social context.
• Acute symptoms can be influenced by the family situation.
• Increased chance of relapse if social situation unfavourable. 

3) Beliefs about Medication

• Families worried about side-effects/addiction --> no addictive behaviour seen.
• "Chemical straitjacket" - notion untrue - do not take away free will, simply help individual deal with world more rationally.

• Schizophrenia can be treated

• There is often a high chance of relapse (less if compliant with medication)

• Social situation and stress strongly influence level of relapse. 

• 1/3 recover normally.

• 1/3 wax and wane.

• 1/3 need permanent drug treatment.

• May not be cured but at least symptoms can be reduced / controlled.