Week 13 - Symptoms of psychosis and risk factors Flashcards
What is meant by the term psychosis?
A mental state that is characterised by a combination of symptoms, including unusual experiences, beliefs and thoughts, which arise from physical or psychological causes
What are schizophrenia spectrum disorders?
A group of conditions characterised by differing degrees or severities of positive, negative or cognitive psychosis
During which period/s of life are people especially likely to develop schizophrenia or schizophrenia spectrum disorders (SSDs)?
Late adolesence and early adulthood
What is the estimated rate of prevalence of SSDs (schizophrenic spectrum disorders) between the ages of 13 to 18?
0.23%
What are the ranges of prevalence of SSDs in adult populations?
Between 0.5-2.47%
What could be the reason for the varying rates of prevalence of SSDs in adulthood?
- Differences between populations
- Methodoligical variations
- The use of different diagnostic procedures
- The specific SSDs themselves
In the USA, roughly how much of the homeless population suffer from schizophrenia?
One-third
What are the three categories of symptoms of SSDs?
- Positive symptoms
- Negative symptoms
- Cognitive impairments
What is meant by the term positive symptoms of psychosis?
Features of psychosis that occur in addition to the person’s ‘normal’ experience
What are the typical features of positive symptoms of psychosis?
- Disordered behaviour and beliefs
- Hallucinations
- Delusions
- Disorganised thought
What is meant by the term hallucinations?
A sensory experience that occurs when a person sees, hears, smells or feels something and believes that it is real, but no one else can sense it
Which senses can a person potentially experience a hallucination in?
Any/all of them
What are the two main manners in which a person can experience a hallucination?
- In some/any of their senses
- If the individual is not able to recognise or verify what is real
What is meant by the term delusions?
Strange or false beliefs about reality which do not change even if the individual is presented with evidence that contradicts or invalidates their views
What are the five main types of delusion?
- Bizarre beliefs
- Paranoid beliefs
- Religios beliefs
- Grandiose beliefs
- Somatic beliefs
What is meant by the term bizarre beliefs?
- The person believes they are receiving special messages from the television or believes their thoughts are being broadcast
What is meant by the term paranoid beliefs?
The individual believes other peoploe are trying to caues them harm, are spying on or plotting against them, or tormenting or ridiculing them
What is meant by the term religious beliefs?
The individual believes they are receiving orders from a deity
What is meant by the term grandiose beliefs?
The invididual believes they have special powers, or imaginary abilities or authority
What is meant by the term somatic beliefs?
The individual believes something unusual is occurring within their body, despite medical evidence to the contrary, or that they are losing control (eg being controlled by external forces or other individuals)
What is an essential attribute of hallucinations and delusions?
That the individual is unaware of the illness
What is meant by the term anosognosia?
The inability to perceive one’s own health condition or diagnosis
Why is anosognosia a problem in the context of SSDs?
It may be difficult for friends or carers to get their loved one to take their medication routinely
What is meant by the term negative symptoms of psychosis?
Features of psychosis that relate to the loss of ‘normal’ function
What are some examples of negative symptoms of psychosis?
- Flattening of emotional responses
- Lack of motivation
- Slowed psychomotor responses
- Social withdrawal
What other condition may negative symptoms of psychosis be confused with?
Depressionq
What emotions are commonly felt during the early stages of psychosis?
- Depressed mood
- Guilt
- Fear
Are the symptoms of psychosis constant?
No - they may evolve across the condition’s progression, treatment and recovery
What is meant by the term mania?
A state of abnormally elevated mental or physical activity
Can mania be associated with any other conditions? If so, which condition?
Yes - bipolar disorder
What are some examples of cognitive symptoms with regard to psychosis?
- Deficits in planning and decision-making
- Memory impairments
- Difficulty in paying attention
What other kinds of behavioural abnormalities may arise due to psychosis?
- Abnormal psychomotor behaviour
- Stereotypies (repeating simple sequences of movement)
What is meant by the term catatonic behaviour?
A motor-function deficit that is marked by a decrease in someone’s movement or reactivity to the environment
What are two examples of catatonic behaviour?
- Decreased reactivity to the environment
- The lack of initiation of behaviours
What is meant by the term primary psychotic disorders?
Mental health conditions whose diagnosis depends on the presence of symptoms of psychosis
What is meant by the term secondary psychotic disorders?
The diagnosis of a mental health condition that includes psychosis, but psychosis is not the major or defining symptom
What is an example of a secondary psychotic disorder?
Bipolar disorder with psychotic features
How is severity of psychosis measured?
Using the ‘Clinician-Rated Dimensions of Psychosis Symptom Severity Scale’
What is the ‘Clinician-Rated Dimensions of Psychosis Symptom Severity Scale’?
The scale for measuring severity of symptoms of psychosis
What are the 8 domains which are used to assess severity of psychosis?
- Hallucinations
- Delusions
- Disorganised speech
- Abnormal psychomotor behaviour
- Negative symptoms (restricted emotional expression / lack of motivation)
- Impaired cognition
- Depression
- Mania
How many major SSDs does the DSM-V describe?
Six
What are the six classifications of SSDs in the DSM-V?
- Schizotypal Personality Disorder
- Delusional Disorder
- Brief Psychotic Disorder
- Schizoform Disorder
- Schizophrenia
- Schizoaffective Disorder
How is the presence of negative symptoms used to distinguish between schizophrenia and schizoaffective disorder?
Schizoaffective disorder uses DSM-V criteria for major depression, which requires depressed mood for most of the day, nearly every day, whereas in schizophrenia, negative symptoms can be present but the frequency is not specified
How might a psychiatrist determine whether a person has delusional disorder or bipolar disorder?
In delusional disorder, manic / depressive episodes occur at the same time as delusions, but someone with bipolar disorder would experience manic / depressive states in the absence of delusions
Why might ‘persistent auditory hallucinations’ alone not be diagnosed as schizophrenia?
It is a single symptom and two or more symptoms are needed for a schizophrenia diagnosis
What might be an exampleof a secondary psychotic disorder?
Bipolar with psychotic features
What is meant by the term prodromal symptoms?
Early symptoms of a disorder that are present before official diagnosis occurs
Which symptoms in the trajectory of psychosis are likely to appear in early adolescence?
Anxiety and depressive symptoms
If one monozygotic twin has schizophrenia, what is the likelihood of the second twin developing the disorder as well?
Around 50%
In general, what is the percentage risk of developing schizophrenia between first-degree relatives?
50%
In general, what is the percentage risk of developing schizophrenia between second-degree relatives?
25%
In general, what is the percentage risk of developing schizophrenia between third-degree relatives?
17.5%
Mutations in which gene can affect both embryonic and adult neural growth and synaptogenesis, and has been linked with schizophrenia?
DISC1
Mutations in the DISC1 gene can affect what?
- Synaptogenesis
- Embryonic neural growth
- Adult neural growth
Are mutations in the DISC1 gene common?
No - so far they have been linked to only one Scottish family’s lineage
What is an SNP (single nucleotide polymorphism)?
The substitution of a single nucleotide for another
What is a nucleotide?
The basic structural unit of nucleic acids such as DNA
Where in the sequence of DNA can an SNP occur?
Anywhere, in both genes and non-coding regions
What is an CNV (copy number variant)?
A type of structural variation - specifically a duplication or deletion which affects a certain number of base pairs
What effect could a CNV (copy number variant) have on the production of a protein within a cell?
If a CNV contains a gene then the impact might alter the level of expression of that particular gene, and therefore the amount of protein produced
Are SSDs the result of a single genetic mutation?
Probably not
What is meant by the term odds ratio?
A statistic used to compare a particular outcome
What does an odds ratio of more than 1 indicate?
That a person exposed to the risk factor is more likely to develop the condition than the person not exposed to the risk factor
Cannabis use might be associated with the development of psychosis. At what age are people most at risk?
In early adolescence (under the age of 15)
How might you measure the effect of cannabis on a person’s brain during a PET scan?
You could inject the person with a radioactive ligand for cannabinoid receptors to visualise where the ligand is binding in the brain
What is the function of the naturally occurring cannabinoid signalling in the brain?
It helps to regulate other neurotransmitters, reducing signalling and keeping the brain ‘stable’ and ‘protected’
Where are cannabinoid receptors located in the brain?
Almost everywhere, they are one of the most widespread types of receptor
To what extent does cannabis use increase the risk for developing an SSD?
The normal risk of developing an SSD is 1%. With some cannabis use that doubles, and with heavy cannabis use it rises to 6%
How does cannabis use affect the frontal cortex and behaviour?
Decreases control over behaviour through reducing frontal cortical activity