Schizophrenia: Historical Perspective and Clinical Features Flashcards
Define psychotic?
Presence of hallucinations, delusions, limited number of behavioural abnormalities (e.g. gross exciteent, overactivity, psychomotor retardation, catatonic)
Schizophrenia: First characterised diagnostic features?
4As
Associations (loose e.g. incoherent speech)
Affect (i.e. how a mood presents- flat)
Autism (social withdrawal)
Ambivalence (+ve/-ve feelings)
List types of schizophrenia symptoms
Positive (halluc, delusions, thought disorder)
Negative (expressive deficits, withdrawal)
Disorganisation (thought disorder)
Affective disturbance (hopelessness, hypomania)
Disturbed behaviour (social withdrawal, depressed features)
Impaired social cognition (lack of empathy)
Neurocognitive function (attention, memory, exec function)
“Classical” schizophrenia subtypes?
NB: these categories are seen as being overalapping and have questionable validity/clinical relevance
- Paranoid: persecutory/grandiose delusions, derogatory auditory hallucinations
- Hebephrenic: disorganisation syndrome (formal thought disorder), affective flattening/incongruity, bizarre behaviour
- Catatonic: multiple motor, volitional + behavioural disorders, stupor and excitement
- Simple: insidious but progressive impoverishment of mental life without development of florid sympsoms
Outline the 2 syndrome model of schizophrenia
Type 1 positive symptoms acute good response to meds reversible no intellectual impairment increased DA receptors
Type 2 negative symptoms chronic poor response to meds irreversible? intellectual impairment cell loss + structural damage
Outline Liddle’s Three Syndromes for schizophrenia
- Psychomotor poverty: speech poverty, decreased spontaneous mvmt, unchanging facial expression, paucity of expressive gesture, affective non-response, lack of vocal inflections
- Disorganisation syndrome: inappropriate affect, poverty of speech content, tangentiality, derailment, pressure of speech, distractibility
- Reality distortion: voices speak to patient, delsuions of persecution, delusions of reference
Risk of death in schizophrenia?
Increased compared to general population (2.5x)
This gap seems to be increasing
[mortality data comparable to heavy smokers]
Main factors why schizophrenia pts have worse physical health (and increased mortality)?
Risk associated w/
- Diabetes: higher risk of glycaemic abnormalities with FEP
- CVD: share same path features: ox. stress, neuroinflamm, mitoch dys
- Antipsychotic treatment
Other contributors why schizophrenia pts have worse physical health (and increased mortality)?
- lack of access to preventative care
- suboptimal cardiac care
- unhealthy lifestyle
- smoking
- social deprivation
- poor diet
- poor compliance with meds
- high level of substance use
Schizophrenia contributors for genetic aetiology
- Susceptibility genes: SNPs, CNVs, rare variants; Neuregulin 1, Dysbindin, DISC1
- Advancing paternal age
- MHC variation: excessive or insufficient synaptic pruning controlled by C4
Possible evidence between cannabis and later psychosis?
40% increase risk in psychosis in individuals who had ever used cannabis
UK prison inmates: cannabis users < 16 -> x2 risk of functional psychosis
Swedish cohort study: heavy use age 18 -> x6 risk of schizophrenia
See: Dunedin, Christchurch, Munich
Reverse causality of cannabis and schizophrenia- alternative theories?
Ppl experiencing early schizophrenia symptoms might turn to cannabis to self-medicate?
Possible mechanism influencing relationship between cannabis and schizophrenia?
Genetic-environmental factors:
COMT (on chr22q11) encodes catechol-o-methyltransferase, involved w/ DA metab in synapse
Common mutation is valine -> methionine -> less active enzyme
MM/MV: cannabis doesn’t increase schiz risk
VV: cannabis does increase schiz risk
Disease progression of schizophrenia?
- Premorbid (asymptomatic)
2, prodromal symptoms (sleep disturbance, paranoia, withdrawal) - progression (episodes of psychosis)
- stable/relapsing (more stable w/ treatment)
Define DUP?
Duration of untreated psychosis
Importance of DUP?
Longer DUPs associated w/ poorer response to meds and poorer symptomatic + functional outcomes during first several years of treatment
Mechanism of relationship between DUP and poor med and symptom response
- active morbid process in brain w/ unchecked psychosis attenuated w/ antipsychotics
- Psychosical effects of prolonged DUP to mediate impact on outcomes
- pts with intrinsically poorer prognosis present later to services- possibly related to symptom profile
Subdomains of negative symptoms?
Alogia: decrease in verbal output/expressiveness
Affective blunting/flattenting: diminished facial emotional expression, poor eye contact, less spontaneous movement, less sponaneity
Avolition: reduced interests/goals, less purposeful acts
Asociality: lack of self-initiated social interactions
Anhedonia: unable to experience pleasure from positive stimuli
Primary VS secondary negative symptoms?
Primary: due to schizophrenia
Secondary: positive psychotic symptoms, depression, PD
Prevalence of negative symptoms?
1/2-3/4 of ppl w/ chronic schizo will have -ve symptoms
Types of abnormal affect in schizophrenia?
Blunted/flattened affect:
- quantitaive abnormality: reduced emotional intensity and variation
(an example of restrictive affect, as it’s depressive affect)
Inappopriate/incongruous affect
- “laughing at bad news”
- qualitative abnormality: affective response is incompatible w/ new ideals/thoughts
Relationship between depressive symptoms and schizophrenia?
Can be seen in separate stages: prodromal, acute episode, post-psychotic- early and late
[look this up]
Relationship between suicide and schizophrenia?
12x more than general population
Highest in young pts at early stage
[males prone on using violent methods]
Risk factors for suicide for schizophrenics?
- young
- male
- high level of education
- no. or prior attempts
- depressive symptoms
- halluc/delusions
- agitation/restlessness
- PTSD
