W11 - Schizophrenia Flashcards
What are psychotic disorders?
Major psychoses (‘madness - cancer of mental illness’)
Examples:
* Schizophrenia* Schizoaffective disorder = schizophrenia and bipolar disorder
* Delusional disorder
* Some depressive and manic illnesses
Schizophrenia is the most important of the above for the following reasons:
1. Early in onset: 18- early 20s
2. Prevalent - 1% of population
3. Disabling and chronic
* Mental state that is out of touch with reality
* Abnormalities of perception, thought & ideas
* Profound alterations in behaviour (bizarre and disturbing alienation)
What is the prevalence of Schizophrenia?
- Affects up to 1% of the population
- No significant influence of culture, ethnicity, background, socioeconomic groups
- Increased in urban areas
Difference between sexes:
Men show an earlier age at onset (18-20 yrs), higher propensity to negative symptoms, lower social functioning, and co-morbid substance abuse than that is women, whereas women display relatively late onset (30-35 yrs) of the disease with more affective symptoms eg. depression. - Before the illness can be recognised there is often a phase in late teenage years associated with social isolation, interest in fringe cults, social withdrawal
- A chronically disabling condition; responsible for a great deal of the population’s morbidity
- In the UK, the cost of treating a patient with schizophrenia through their life is about six times the cost of treating a patient with heart disease.
What are the three classes into which schizophrenia symptoms can be grouped?
Positive:
* Hallucinations (e.g. visual, auditory)
* Delusions
* Disorganised thought/speech
* Movement disorders
Negative:
* Social withdrawal
* Anhedonia - lack of pleasure
* Lack of motivation
* Poverty of speech
* Emotional flatness
Cognitive:
* Impaired working memory
* Impaired attention
* Impaired comprehension
Two or more of these symptoms must persist for at least 6 months to be classed as schizophrenia
What are hallucinations?
Perception experienced without stimulus.
(Functional Hallucination)
Most commonly auditory
Patients hears
Voices talking about them (3rd person)
Voices talking to them
Voices giving a running commentary
Voices echoing their thoughts (thought echo)
Patients may engage in a dialogue with the
voices or obey their commands.
What are delusions?
A fixed/ unshakable belief. Not
consistent with cultural/ social norms.
Often paranoid or persecutory
E.g. under control of an external influence,
thoughts known to other people because they are transmitted by radio and TV
Passivity of thoughts and actions
What Motor, volitional and behavioural disorders do schizophrenia accompany?
- Peculiar forms of motility, stupor, mutism, stereotypy, mannerism,
negativism, spontaneous automatism, impulsivity
– Stereotypies: purposeless, repetitive acts
– Bizarre postures, strange mannerisms
– Altered facial expression – grimacing
– State of catatonia – motionless, mute, expressionless, uncomfortable or contorted postures
– State of catalepsy – waxy flexible
– Bouts of extreme hyperactivity (destructiveness; walk around naked)
– Impulsive behaviour – violent acts; murder w/o reason
What is a formal thought disorder?
A disorder of conceptual thinking,
reflected in speech that is difficult to
understand and rapid shifts from one
subject to another. New words are
invented (neologisms).
What is social withdrawal?
Patients withdraw from their families and
friends and spend a lot of time on their own.
Lack of initiative or motivation
Do not want to do anything.
No longer interested in things that used to
interest them.
What are features of formal thought disorder?
- Disturbances in thinking → unintelligible speech
- Derailment of speech
- Loosening of associations; failure to follow train of though to its conclusion
- Poverty of speech (speech fails to convey sense/information)
– Manifests as distorted or illogical speech
What are cognitive deficits?
Deficits in SELECTIVE attention, problem solving
and memory
- Eg. They would be unable to differentiate between someone talking and the ticking of a clock.
Blunted affect
Decreased responsiveness to emotional issues.
Incongruous affect. Expression of affect
inappropriate to circumstances.
What are insights?
An understanding of what is wrong.
Insight lacking in schizophrenia.
Patients usually do not accept that any
thing is wrong or that treatment is necessary.
What are the 4 phases of schizophrenia?
- The Prodrome
Late teens/early twenties: often mistaken for depression or anxiety. Can be triggered by stress. - The Active/Acute Phase
Onset of positive symptoms
Differentiation of what is and isn’t real becomes difficult - Remission
Treatment -> return to ‘normality’ - Relapse
They will usually switch between Remission and Relapse.
Schizophreniform positive symptoms for at least a month, but under 6 months
What is the aetiology of schizophrenia
Nature vs Nurture
Genetics:
* SCZ isn’t directly inherited, but
can ‘run in families’
* ‘Candidate’ risk genes:
* Gene deletions
* Gene mutations
Environmental Factors:
* Pregnancy/birth complications
* Stress
* Drug use
Nature AND Nurture
How do we know the Schizophrenia is caused by genetic influence?
Twin studies done in monozygotic twins.
-50% chance of developing schizophrenia if one twin diagnosed
In dizygotic twins,
~14% chance of developing
schizophrenia if one twin diagnosed
What are ‘Candidate’ Genes?
This is a polygenic disorder.
We know the exact genetic anomalies that lead to
these disorders:
Sickle-cell disease
Cystic fibrosis
Colour blindness
- COMT
- DISC1
- GRM3
Some of the ‘risk’ or
‘candidate’ genes for schizophrenia
Possessing these abnormal genes does not
mean you will definitely get schizophrenia –
similarly, some people who have schizophrenia
do not have these genetic abnormalities
