Clinical Features of Schizophrenia Flashcards
Describe the clinical presentation of schizophrenia, including the nature of the symptom domains of the illness, positive symptoms, negative symptoms, affective symptoms, neurocognitive deficits, and impaired social cognition Understand the aetiological theories of schizophrenia, considering particularly the heritable genetic component, environmental risk factors, and interactions between the two Describe the neurodevelopmental model of schizophrenia
Define psychosis
A loss of contact with reality - the presence of hallucinations, delusions, or a limited number of severe abnormalities of behaviour, such as gross excitement and overactivity, marked psychomotor retardation, and catatonic behaviour
Name the 2 main psychotic illnesses
Schizophrenia, bipolar disorder
State the disorders encompassed by schizophrenia
Brief reaxtive psychosis, organic psychosis, delusional disorder, psychotic depression, schizoaffective disorder
Give the 3 main comorbidities of bipolar disorder
Anxiety, substance misuse, borderline personality disorder
Name the symptom domains of schizophrenia
Positive, negative, neurocognitive, disorganisation, affective dusturbance, disturbed behaviour, social cognition
Describe the neurocognitive symptoms of schizophrenia
Dysfunction in attention, memory, and executive function
Describe the positive symptoms of schizophrenia
Delusions, hallucinations
Describe the negative symptoms of schizophrenia
Affective flattening, alogia, avolition, anhedonia
Describe the disorganised symptoms of schizophrenia
Formal thought disorder
Describe the affective disturbance symptoms of schizophrenia
Suicidal ideation, hopelessness, excitement, hypomania
Describe the behavioural symptoms of schizophrenia
Social withdrawal, thought disturbance, anti-social behaviour, depressed behaviour
Describe the social cognition symptoms of schizophrenia
Impaired emotion processing, theory of mind, and social relationship perception
Name the 4 classic schizophrenia subtypes
Paranoid, hebephrenic, catatonic, simple
Describe paranoid schizophrenia
Characterised by persecutory or grandiose delusions and derogatory auditory hallucinations
Describe hebephrenic schizophrenia
A disorganisation syndrome, characterised by formal thought disorder, affective flattening, and bizarre behaviour
Describe catatonic schizophrenia
Multiple motor, volitional, and behavioural disorders, accompanied by stupor and excitement
Describe simple schizophrenia
Insidious but progressive impoverishment of mental life, without development of florid symptoms
Describe Crow’s 1985 two-syndrome model of schizophrenia
Type 1 schizophrenia was an acute illness featuring positive symptoms - hallucinations, delusions, and thought disorder - with a good response to medication and no intellectual impairment. Type 2 schizophrenia was a chronic illness featuring negative symptoms - affective flattening, speech poverty, loss of drive - with a poor response to medication and some intellectual impairment
State the problems with the four-subtype model of schizophrenia
The subtypes are temporally unstable, overlapping, and of questionable validity and clinical relevance
Name the 3 schizophrenia syndromes proposed by Liddle & Barnes in 1990
Psychomotor poverty, disorganisation syndrome, reality distortion
Describe the psychomotor poverty subtype defined by Liddle in 1990
Poverty of speech, decreased spontaneous movement, unchanging facial expressure, affective non-response, lack of vocal inflections
Describe the disorganisation syndrome subtype defined by Liddle in 1990
Inappropriate affect, poverty of content of speech, tangentiality, derailment, distractibility
Describe the reality distortion subtype defined by Liddle in 1990
Auditory hallucinations, delusions of persecution, delusions of reference
When is the typical onset of schizophrenia?
Middle to late adolescence, with age of onset often earlier in males (Castle et al, 1998)
Describe the typical initial symptoms of schizophrenia
Change in personality, decrease in academic, social, and interpersonal functioning
What is the male to female ratio of schizophrenia?
1.4:1
Which physical health problems are more common in schizophrenia?
Diabetes mellitus (due to schizophrenia and the effects of antipsychotics), cardiovascular disease
Why is the risk of cardiovascular disease increased in schizophrenia?
HPA and mitochondrial dysfunction, peripheral and CNS inflammation, oxidative and nitrosative stress, common genetic links, epigenetic interactions
State some reasons why schizophrenia increased morbidity and mortality
Lack of access to and uptake of preventative care, social deprivation, under-diagnosis and treatment of physical illness, poor compliance with medical treatment, unhealthy lifestyle (higher incidence of smoking and substance use), sleep and circadian disorders
Name 3 genes associated with schizophrenia
Neuregulin 1, dysbindin, disrupted in schizophrenia 1 (DISC1)
Describe the synaptic pruning hypothesis of schizophrenia (Sekar et al, 2016)
The risk of schizophrenia is greater in those with complement C4 alleles which produce more C4A protein - involved in marking synapses for destruction by microglia. Excessive or inappropriate pruning of neural connections could lead to schizophrenia
Why is advancing paternal age a risk factor for schizophrenia? (Sipos et al, 2004)
Accumulation of de novo mutations in paternal sperm
Describe the relationship between cannabis use and schizophrenia
Cannabis use is a risk factor for psychosis - the Dunedin cohort study found a 40% increased risk of psychosis in cannabis users compared to non-users, with the risk greater in the most frequent users (Moore et al, 2007). However, it is unclear if this is causal - individuals with early schizophrenia symptoms may be more likely to try cannabis or use it to self-medicate or normalise their symptoms
Which genotype produces the greatest risk of schizophrenia following adolescent cannabis use?
The val/val COMT gene mutation on chromosome 22q11
State some prodromal symptoms of schizophrenia
Dysphoria, suspicion, perceptual distortion, poor concentration, sleep disturbance, paranoid notions, functional deterioration, social withdrawal, emotional withdrawal, academic decline, ritualistic behaviour, lack of drive
Why are patients with prodromal symptoms of schizophrenia not treated?
Many of them will never develop any psychiatric illness
How does a delay in treating psychosis affect outcomes? (McGlashan & Johannessen, 1996)
A longer duration of untreated psychosis correlates with poorer medication response and worse symptomatic and functional outcomes
Define alogia
Decrease in verbal output or verbal expressiveness
Define affective blunting
Diminished facial emotional expression, poor eye contact, and decreased sponatenous movement
Define avolition
A subjective reduction in interests, desires, and goals, and behavioural reduction in self-initiated and purposeful acts
Define anhedonia
Loss of ability to experience pleasure for positive stimuli
Describe 2 forms of abnormal affect
1) Blunted affect - reduction in emotional intensity and variation
2) Incongruous affect - affective response incompatible with thoughts or ideas expressed, e.g. laughing at bad news
State 2 reasons why negative symptoms are difficult to identify
1) Antipsychotic medication side effects are similar to negative symptoms
2) Apparent negative symptoms can be due to positive symptoms - e.g. social withdrawal due to paranoid delusions or to avoid distracting psychotic experiences
What percentage of people with schizophrenia exhibit some negative symptoms?
50-70%
Describe the relationship between schizophrenia and suicide (Carlborg et al, 2010)
Schizophrenia patients are 12x more likely to commit suicide than the general population, with 4-5% of patients dying by suicide. Rates are highest in younger patients at an early stage of their illness and immediately after a psychotic episode
At what point would an SSRI be considered to treat depressive symptoms in schizophrenia?
If severe, within 6 months of a psychotic episode - otherwise only if more than 6 months after a psychotic episode
Give some risk factors for suicide in schizophrenia
Young patient, male, high level of education, fear of mental disintegration, prior suicide attempts, depressive symptoms, active hallucinations and delusions, agitation, presence of insight, comorbid PTSD or substance abuse
What is the only protective factor for suicide in schizophrenia?
Adherence to effective treatment
Define thought blocking
A disorder of the stream of thought
Define thought insertion
A disorder in control of thought
