Schizophrenia Flashcards
What are the symptoms of schizophrenia?
- Positive: (often the most dramatic and initially the most distressing)
- – Hallucinations = perception in the absence of a stimulus
- – Delusions = false belief not shared by others
- – Lack of insight
- – Failure to appreciate that symptoms aren’t real
- – Thought disorders = manifests as illogical and distorted speech
- Negative = social withdrawal, self-neglect, lack of motivation, paucity of speech, etc.
- – Tend to cause the most problems as they tend to be longer lasting
What are the 3 phases of schizophrenia?
- Predromal phase
- – Symptoms not yet obvious but person begins to deteriorate
- – May withdraw socially, exhibit vague or odd speech, express strange ideas and express little emotion
- – May be a trigger to suggest that they need more treatment from mental health professional if have already been treated for schizophrenia
- Active phase
- – Symptoms become apparent
- – Triggered by stress?
- Residual phase
- – Return to a predromal-like level of functioning
- – Striking symptoms lessen
- – Some symptoms may remain
What are some problems with diagnosis and labelling in psychiatry?
- Diagnostic labels are decided upon by select groups of professionals deciding what should be a disorder
- No consistent evidence of a biological aetiology
- Patients can’t self report very well
- No tests for any of the FPDs (functional psychiatric diagnosis)
- Changes to diagnostic criteria between DSM-IV and DSM-V made to improve reliability rather than based on increased knowledge of the ‘schizophrenia disease’
- If something is reliable it doesn’t mean it is valid; however if we can’t reliably diagnose something then the construct cannot have scientific validity
— Thus schizophrenia can’t be scientifically valid - For schizophrenia to have validity for being an illness we would expect the construct to relate to:
— Outcome/prognosis
• No evidence that people receiving a diagnosis have similar prognosis
• Greatest predictors of recovery are psycho-social: work performance, social skills, achievement, money
— A biological aetiology
— Specificity
— Kraepelin, 1896 began to isolate symptoms of schizophrenia into a separate category
How could the language used in the description of schizophrenia affect public opinion?
Van Os, 2016
- The language used in the description of schizophrenia (in a wide range of sources) is highly suggestive of a distinct, genetic brain disease
— Could this impact on public opinion of schizophrenia?
- The best way to inform the public and provide patients with diagnoses is to use the broad, heterogenous psychosis spectrum syndrome that really exists
— E.g. schizoaffective disorder, schizophreniform disorder
George and Klijn, 2013
- Suggest that a modern name for schizophrenia would diminish self-stigma
- Japan changed the name of schizophrenia in 2006
— Stigma diminished as a result and the new name was more acceptable to patients
— Better adherence and less relapse due to more acceptable explanations of the diagnosis by psychiatrists
— Patients were more willing to seek help
— There were fewer suicides
Evans-Lacko et al., 2012, have shown that there is a trend for patients’ self-stigma to arise from internalisation of surrounding stigmatising attitudes
Why does the medical model persist in schizophrenia?
- Funding and interest of drug companies, researcher and mental health professionals
- Bias against publishing negative findings
- Media representation
Explain the Rosenham experiments
Rosenham - 1975
- Sent 8 pseudopatients to a variety of psychiatric hospitals
- – They told the doctors that they could hear a voice in their head that kept saying “empty”, “hollow” and “thud”
- – Other than that lie, they acted no different to usual
- – Rosenham himself was a pseudopatient
- – All of them employed pseudonyms
- – Some were psychologists or psychiatrists – they alleged a different occupation
- Immediately upon admission to the psychiatric ward, the pseudopatient ceased simulating any symptoms of abnormality
- Initial nervousness/anxiety upon admission
- Motivated to behave sanely so that they could get out
- Medication was not swallowed
- Failure to detect sanity during the course of hospitalisation
- – Physicians operate with a strong bias toward the Type 2 error (more inclined to call a healthy person sick)
- All were diagnosed with psychiatric illnesses (schizophrenia or bipolar)
- – And admitted to hospital
- Couldn’t get out unless they agreed with the doctor that they were insane and pretended to get better
- All were released with diagnosis of “schizophrenia in remission”
- – This is actually quite rare – most people still have some schizophrenic symptoms when released from hospital
- “Round 2” of experiment occurred in a research and teaching hospital where the staff had heard of the findings, but doubted that such an error could occur in their hospital
- – Staff were informed that at some time during the following 3 months, 1 or more pseudopatients would attempt to be admitted into the psychiatric hospital
- – Each staff member was asked to rate each patient who presented himself at admissions on the likelihood that they were a pseudopatient
- – 41 patients were alleged, with high confidence, to be pseudopatients by at least one member of the staff
- – But no genuine pseudopatients (from Rosenham) were presented during this period
- – But if this had been widely published, could members of the public have acted as pseudopatients?
- – Cannot prove that they are not pseudopatients
How reliable is a diagnosis of schizophrenia?
Cooper et al, 1972
- US and UK psychiatrists asked to diagnose patients (via videotaped clinical interview) with schizophrenia or not
- 69% of US psychiatrists diagnosed vs 2% of UK
- The British psychiatrists diagnosed the patients with clinical depression twice as often
- The American psychiatrists diagnosed the patients with schizophrenia twice as often
- Different diagnoses between countries - problems with reliability and cultural differences in interpretation of symptoms and thus in diagnosis
Herron et al., 1992
- In 1992 researchers identified 16 systems of classifying ‘schizophrenia’
- Of 248 patients, the number diagnosed as schizophrenic by these systems ranged from 1-203
Bentall et al, 1988
- A review of the research in each of the 4 validity areas (symptoms, aetiology, prognosis and treatment) concluded that “schizophrenia” is not a useful scientific category and that for all these years researchers have been pursuing a ghost within the body of psychiatry
Craig and Hwang, 2000; Crow, 2010; Torgalsboen, 1999
- There is no evidence that there is a set of ‘schizophrenic’ behaviours and experiences that occur together but do not occur in other psychiatric conditions
- No single “schizophrenic profile” was elicited by WHO in 1973
- Most people diagnosed schizophrenic have sufficient symptoms of other disorders to earn additional diagnoses
- This co-morbidity has been found in relation to depression, bipolar disorder, personality disorders, substance abuse, PTSD, anxiety disorders, OCD, panic disorder and dissociative disorders
- There is no evidence that people receiving the diagnosis share a common prognosis
- The diagnosis has very little predictive validity
Ellason and Ross, 1995
- People with dissociative identity disorder have more schizophrenic symptoms than people diagnosed as schizophrenic
Whaley, 2001
- Found that the reliability of the DSM is low when assessed by inter-rater reliability
- Evidence for low reliability when using the DSM to diagnose schizophrenia
Prescott et al, 1986
- Analysed the test-retest reliability of several measures of attention and information processing in 14 chronic schizophrenics
- Performance on these measures was stable over a 6-month period
- Shows that there is a high test-retest reliability when using these measures of attention and information processing to diagnose schizophrenia
Cochrane and Bal, 1987
- Reported that afro-carribean people living in the UK are 7 times more likely to be diagnosed schizophrenic
- This may be because they experience more stressors, or they are subject to cultural bias
Whaley, 1997
- Found differences in the incidence of schizophrenia in black and white americans
- Cross-culturally there is a lack of validity as ethnic differences in expression are overlooked or misinterpreted
What is required for a diagnosis of schizophrenia?
- At least 2 of these over the last month:
- – Delusions
- – Hallucinations
- – Disorganised speech
- – Grossly disorganised or catatonic behaviour
- – Negative symptoms (blunted affect, alogia [lack/decline of speech], avolition [lack/decline in motivation]
- Plus a marked decline in at least 1 of these over the past 6 months:
- – Functioning in work
- – Interpersonal relationships
- – Self-care over the past 6 months
- Associated with a more persistent “psychotic presentation”
What evidence is there to suggest that genetics play a role in the development of schizophrenia?
Gottesman, 1991
- 57 twin pairs studied (24 MZ, 33 DZ)
- Both of the twins had some sort of psychiatric abnormality, with one having a diagnosis of schizophrenia
- Age range: 19-64
- If both twins have schizophrenia: MZ = 42%, DZ=9%
- Genes appear to play a role in schizophrenia because the concordance rate is higher in MZ twins than DZ twins
- – But not 100% hence environmental factors must play a role
- Life events may cause epigenetic changes
What is the dopamine hypothesis?
- Early support = researchers learnt that medication that seemed to be helpful had the effect of reducing dopamine transmission
- – Inferred dopamine cause of symptoms
- – Indirect pharmacological evidence
- Excessive dopamine activity
- – Dopamine transmission: characteristic of neurons that link the midbrain with the cerebral cortex
- – Role of dopamine receptors: guide attention and attention-related actions
- – In schizophrenia, neurons that communicate using dopamine fire too often and transmit too many messages
- – There could also be excessive numbers of dopamine receptors
What evidence is there for/against the dopamine hypothesis?
Haracz, 1982: FOR
- Further post-mortem research revealed increased dopamine receptors only found in those taking ‘anti-psychotic’ meds shortly before death
- Indirect pharmacological evidence still makes up the bulk of the support
— Despite extensive study of tissue samples obtained from schizophrenics
- Direct support is either uncompelling or has not been widely replicated
- The DA hypothesis appears to be limited in the range of patients to which it applies
— It is also restricted in theoretical scope
— It does not account for social aspects of schizophrenia
- Some of the differences most consistently found can be explained by effects of medication
- People’s experiences impact on neurotransmission and brain structure
— The traumagenic neurodevelopmental model of psychosis
Cromby, 2013 AGAINST
- Excesses of dopamine are not found in all people given a diagnosis of schizophrenia
- Dopamine excesses are found in people given many other diagnoses
— Bentall 2003
- Excessive dopamine is neither necessary nor sufficient as a cause of the experiences associated with a diagnosis of schizophrenia, nor is it exclusively associated with this diagnosis
- Amongst people given a diagnosis of schizophrenia, dopamine levels are only excessive at times when they are most distressed
— Bentall 2003
What are some psychosocial risk factors?
Heins et al, 2011
- 272 patients with psychotic illness had their symptoms assessed on the Positive and Negative Syndrome Scale
- 258 siblings + 227 healthy comparison subjects were assessed with the Structured Interview for Schizotypy-Revised
- Those with a psychosis related diagnosis had OR = 4.5 for childhood abuse and neglect compared with non-diagnosed controls and were 2.6x more likely to have experienced abuse and neglect compared to non-diagnosed siblings
- Childhood abuse but no neglect was associated with positive but not negative symptoms in a dose-response fashion in all 3 groups
Eaton, 1980:
- Poverty is associated with many of the direct causal factors (e.g. childhood neglect and abuse) and reduced access to protective factors
- Relationship between schizophrenia and poverty is one of the most consistent findings in the field of psychiatric epidemiology
Halpern and Nazroo, 2000
- Being in a minority ethnic group has been found to be associated with increased risk in numerous countries
- Increased risk factor lower in neighbourhoods where high density of a given ethnic group
- In UK, people in a minority-ethnic group are 3.6x more likely to be diagnosed ‘schizophrenic’ than white majority
— 9-12x more likely to get diagnosis if Afro-Caribbean
- Possible reasons:
— Biased diagnostic procedures
— Discrimination, poverty and social isolation
Traumagenic neurodevelopmental model (Read et al, 2014)
- Based on evidence showing that structural abnormalities sometimes present in brains of people with schizophrenia diagnosis are similar to those who have been abused
- Abusive experiences result in changes to brain often found in those diagnosed as schizophrenia
What is the role of cannabis in schizophrenia?
- People with established schizophrenia smoke more cannabis than people in the general population
- Been suggested that early cannabis use is an attempt to relieve stress of developing illness, rather than being a causal factor
- But studies have found a link between early cannabis use and schizophrenia long before development of schizophrenia symptomology
- Cannabis use may precipitate a psychotic episode in those with pre-existing liability
Henquet, Murray, Linszen and Van Os, 2005 - Cannabis use has consistently been found to increase the risk for the psychosis outcome at follow-up
- Individuals with expression of vulnerability to psychosis may be more likely to start using cannabis so as to “self-medicate” their distress
— But researchers have found stronger associations between cannabis use and psychotic experiences in the absence of distress, making self-medication unlikely - Regular cannabis use can induce dopamine sensitisation
— Individuals become progressively more vulnerable to dopamine-induced perceptual and cognitive aberrations that may progress to full-blown psychotic symptoms - Cannabis is neither a necessary nor sufficient cause; it is a component cause
How can schizophrenia be treated?
- Antipsyschotic pharmacotherapy is the standard care of schizophrenia
- – Effectively controls acute psychotic symptoms
- – Most popular drug = clozapine
- – Shown to reduce positive and negative symptoms
- – Adherence rates are low due to bad side effects
- Psychological therapy is only effective after antipsychotic medication has started working
- – CBT = reduces persistent symptoms and improves insight
- – Family therapy = support and education for patients and for their families
- – Psychoeducation = reduces relapse rates, admissions, symptoms
What evidence is there for the effectiveness of schizophrenia treatment?
May and Tuma, 1965
- Experimental study of 5 treatment methods
- 47 male and 53 females with schizophrenia
- Randomly assigned to:
— Control
— Individual psychotherapy alone
— Tranquilising drug alone
— Electroshock
— Individual psychotherapy plus tranquilising drug
- Follow up for 3 years after first admission
- Patients treated with drugs (with or without psychotherapy) did significantly better than the control group
— They also did better than those given ECT or psychotherapy, but not statistically significant
- Patients given ECT spent less time in hospital during the 3 year follow up
- Statistically significant difference
- Currently NOT recommended for the treatment of schizophrenia (according to NICE guidelines)
Hamann, Cohen, Leucht, Busch and Kissling; 2007
- Participants = 107 psychiatric state hospital inpatients with a schizophrenia
- Studying whether shared decision making in antipsychotic drug choice would influence long term outcome
- Cluster-randomised controlled design
- An SDM program on antipsychotic drug choice consisting of a decision aid and a planning talk between patient and physician was compared with routine care
— Outcomes to be measured = long-term compliance and rehospitalisations
- 6 month and 18 month follow-up
- Overall, there were high rates of non-compliance and rehospitalisation
- No differences between intervention and control groups
— But when confounding factors were controlled for, there was a positive trend that patients in the SDM intervention had fewer rehospitalisations
- Higher hospitalisation rates were also associated with a higher desire of the patient for autonomy and better knowledge at discharge
