Week 5 Lecture - Psychosis (SZ) Flashcards
what is psychosis
Diagnostic label given to those whose experiences are outside the cultural norm
what does psychosis include
○ Hallucinations: experiencing things (like hearing voices or seeing things) which others cannot verify (sensory in origin)
○ Delusions: Holding strong beliefs (e.g. there is a conspiracy against them) that others do not share (cognitive in origin)
○ Disordered thoughts: Difficulties putting coherent thoughts together and concentrating
○ A generally disturbed relationship with reality
types of psychotic disorder
- Schizophrenia: hallucinations (e.g. hearing voices), delusions, lack of motivation
- Bipolar Disorder: mood disorder with ‘swings’ between elation (mania) and depression
- Schizoaffective Disorder: elements of bipolar & schizophrenia
- Postpartum (Puerperal) Psychosis: psychotic symptoms following childbirth
- Delusional Disorder: holding a firm belief that is not true
what are psychotic symptoms divided into?
○ Positive Symptoms (experiences which are added to the ‘normal’ behavioural repertoire – hallucinations, delusions, disorganised speech)
○ Negative Symptoms (emotional withdrawal, apathy, lack of motivation, self-neglect)
○ Additional symptoms e.g. depression, suicidal thoughts, problems with memory, attention and theory of mind, etc.
SZ epidemiology
- Schizophrenia is the most prevalent psychosis
- Lifetime schizophrenia prevalence (as morbid risk):
○ 7.2/1,000 persons (0.7% of the population) (nearly always rounded up to 1% for ease)
○ Equal risk for men and women
§ 18-25 onset for men for first onset but 2 peaks for women at 30s and 40s
○ Mortality risk 2-3 time higher in people diagnosed with schizophrenia (median SMR = 2.7)
○ Excess mortality equivalent for men and women diagnosed with schizophrenia - McGrath et al (2008)
- Lifetime schizophrenia prevalence (as morbid risk):
SZ course
most remain on medication and live in community
SZ outcome measures
symptom remission
social functioning
symptom remission
e.g. not hearing voices
social functioning
e.g. still hearing voices but going back to work and having good relationships
outcomes of SZ measured in what?
survivors
stats outcomes for SZ
- Approximately 40% of excess mortality in schizophrenia is due to suicide
- Approximately 5% of people diagnosed with schizophrenia commit suicide (rate = 0.3% for those with no disorder)
- For patients, suicide risk is associated with being male, younger, agitated, and less adherent to medication.
what causes psychosis?
- Psychosis is a complex end-point with contributions from biology (e.g. genetics, biochemistry), psychology (e.g. stress, trauma) and social circumstances (e.g. inequality, racism)
genetic causes of psychosis
- Genetic links strongly indicated by heritability.
- The chance of developing schizophrenia is:
○ 1 in 100 for individuals with no relatives with schizophrenia
○ 1 in 10 for individuals with 1 parent with schizophrenia
○ 1 in 8 for individuals with 1 non-identical twin with schizophrenia
○ 1 in 2 for individual with 1 identical twin with schizophrenia
But - No single causal genes or single ‘gene of major effects’ identified; rather, many genes appear to interact to increase vulnerability to psychotic experiences (Merikangas et al 2022).
- The chance of developing schizophrenia is:
neurochemical causes of psychosis
- The dopamine hypothesis: Developed in the 1960s following the discovery of the antipsychotic (neuroleptic) drug chlorpromazine which was very effective in reducing positive psychotic symptoms.
- Chlorpromazine is a dopamine antagonist (i.e. it blocks dopamine-mediated neurotransmission in the brain). (very effective at reducing positive symptoms)
- Led to the conclusion that schizophrenia was a hyperdopaminergic state (i.e. characterised by an overproduction of the neurotransmitter dopamine).
dopamine theory of psychosis
- Amphetamine and cannabis use (which increase dopamine production) can cause psychotic symptoms in non-psychotic users.
- Amphetamine and cannabis EXACERBATE psychotic symptoms in users diagnosed with schizophrenia
- Patients with Parkinson’s (a condition characterised by REDUCED dopamine production) treated with the dopamine enhancing drug levodopa can experience psychotic side effects mimicking the symptoms of schizophrenia.
- both increase dopamine in NS and can cause symptoms and exacerbate symptoms already there
- L-dopa was used to increase dopamine in NS in PD - created psychotic symptoms in some people that were the same as in SZ
critique of dopamine theory of psychosis
○ Delayed and selective impact of chlorpromazine
○ Increased dopamine transmission is not pathognomonic for (i.e. specific to) schizophrenia; those diagnosed show substantial neurochemical heterogeneity (Grunder &Cumming, 2016).
○ Research now indicates that glutamate, GABA, ACh, and serotonin (5-HT) also implicated in psychotic experiences
○ Conclusion: Neurotransmitter levels are involved in, but are not direct causes of schizophrenia symptoms
trauma as a psychosocial cause
- Research evidence shows a clear link between childhood trauma and the subsequent development of psychosis (e.g. Barrigon et al, 2015; Duhig et al, 2015)
- In a meta-analysis of population and case-control studies Varese et al (2012) concluded that adversity and trauma (sexual abuse, physical abuse, emotional/psychological abuse, neglect, parental death, and bullying) are strongly associated with an increased risk for psychosis.
- Trauma at the top of the list
- Childhood trauma significant link
- Adversity in childhood also big link
disadvantage as a psychosocial cause
- Consistent evidence for an elevated risk of psychosis in relation to:
○ Socioeconomic deprivation
○ Migration (both first and second generation migrants) in all developed countries
○ Racial discrimination (increased rates of psychotic disorders in ethnoracial minoritized groups, particularly people of Black ethnicities)
Kirkbride et al (2024)- These relationships are complex and can be reciprocal.
- For example, compromised mental health can lead to poorer achievement, lower paid employment, and consequently lower socio-economic status.
○ Would lead to association between SES and psychosis as a result despite the lack of a causal link - Both the necessity to, and the act of migrating are also socially dislocating, and stressful – factors which independently amplify psychosis risk.
delusions as a cause -
Maher’s proposal is a ‘one factor’ theory – delusional thinking is characterised by only one departure from normality – the anomalous thought
one-factor theory
- One factor theory of delusions supported (at the time) by:
○ Evidence that perception itself remains normal and unchanged in psychosis; and
○ The absence of conclusive evidence that psychotic patients “…show abnormalities in logical reasoning” (Maher, 1974).
normal explanation vs anomalous experience
○ Normal explanation: An explanation acquired through the operation of a normal (intact) cognitive processes
○ Anomalous experience: An (intuitive) awareness that something is different, odd or peculiar.
continuum model of psychotic experiences
- Many psychotic experiences exist on a continuum from good to poor mental health and are not unique to psychosis
- From a survey of psychiatric symptoms in >8000 randomly sampled people Bebbington et al (2013) found that “…paranoia is so common as to be almost normal”.
- Similarly Beavan et al’s (2011) meta-analysis found that ‘hearing voices’ when no-one was there was reported
stress-vulnerability model
- Proposed by Zubin and Spring (1977) the model suggests that people are more or less vulnerable to psychosis as a result of biological, psychological and social factors
- The resulting vulnerability interacts with stressors which can ‘trigger’ psychotic experiences and distress
- The psychosocial milieu can also mitigate or exacerbate the intensity of psychotic experience
- It follows from this model that a person may be constitutionally vulnerable to psychosis but, in the absence of sufficient stress, does not experience schizophrenia.
stress vulnerability model lays flat
homeostatic balance
stress vulnerability model lays to right
increased wellbeing
stress vulnerability model lays to left
more ill health
problems with psychiatric diagnosis
- In organic disease diagnosis provides an EXPLANATION for why we experience the symptoms we report.
- In psychiatry, on the other hand, diagnoses are substantially DESCRIPTIONS of the symptoms reported which offer no explanation.
- Problems “…stem from applying physical disease models and medical classification to the realms of thoughts, feelings and behaviours.” (BPS, 2017) [i.e. the problem regarding behaviour exclusively as a ‘symptom’]
formualtion
Formulation can be defined as the process of co- constructing a hypothesis or “best guess” about the origins of a person’s difficulties in the context of their relationships, social circumstances, life events, and the sense that they have made of them.” (Johnstone, 2018)
- “Formulations often take the form of written summaries or diagrams, developed by a process of collaboration between the professional and the service user. (BPS, 2017)”
formulation and psychosis
- Formulation is a process of collaborative ‘meaning making’
- The sense that someone makes of their experience is influenced by many factors, including culture, past experiences, and the response of people around them.
- How someone interprets psychotic experiences will affect how distressed (or not) they feel about them.
- In managing psychotic experiences it is not the symptoms that are the target for treatment, it is the distress associated with the symptoms
psychological formulations for psychosis
- Summarise a client’s core problems
- Show how a client’s difficulties may interact – informed by psychological theories and principles
- Suggest (on the basis of psychological theory) why the client has developed these difficulties at this time and in these situations
- Lead to a plan of intervention – based on the psychological processes and principles already identified
- Are open to revisions and reformulations
what can help psychosis?
- A range of interventions can help individuals experiencing psychological distress which is understood as ‘psychosis’
- The benefit from any given intervention is likely to depend on the sense the client has made of their experiences
- Some interventions help directly with ‘symptoms’, others address the impact of psychotic experiences
- Psychological interventions recommended by NICE & the BPS are ‘Evidence Based’
what basic needs need to be addressed in psychosis?
- Does the individual have somewhere safe to live?
- Are they facing discrimination?
- Are they ostracised/isolated in their community?
- Do they have a job? [NICE (2014) recommends that services should offer people tailored help with finding and keeping good employment]
CBTp
- Garety et al (2001) A cognitive model of positive symptoms of psychosis
- If you can modify the negative appraisals you can modify distress
- Collaborative alliance which aims to find out:
○ What’s up? – getting the details of the individual’s experiences (e.g. paranoia, voices)
○ Why me? – thinking about longer term risk factors / difficulties that may have influenced the current presenting issues (e.g. bullying / trauma)
○ Why now? – recent stressful triggers
○ Why still? – factors that keep the individual stuck with problematic behaviours, thoughts or feelings
○ What helps? – factors that protect the individual from feeling worse and developing helpful coping strategies
family interventions/meetings
- Should be offered to “…all families of people with psychosis or schizophrenia who live with or are in close contact with the service user” and should
○ include the person with psychosis or schizophrenia if practical
○ be carried out for between 3 months and 1 year of referral
○ include at least 10 planned sessions
○ can be either a single-family or multi-family group intervention
○ have a specific supportive, educational or treatment function
