L18 - Schizophrenia 1 Flashcards
1
Q
What is schizophrenia/psychosis?
A
- Neurodegenerative disorder in the young
- Cog impairment central to the concept
- Madness can be divided into a small number of diseases with different types of brain pathology and with differing aetiologies
- Splitting of the mind, not personalities
2
Q
What are the positive symptoms?
A
- Those additional to normal experience and behaviour
- Positive symptoms’ describe psychosis and typically include delusions, hallucinations and thought
disorder
3
Q
What are the negative symptoms?
A
- The lack or decline in normal experience or behaviour
- Negative symptoms’ describe inappropriate or non-present emotion, poverty of speech, and lack
of motivation - Factor analysis puts symptoms into 3 semi-independent factors i.e. three-factor models of
‘schizophrenia’ - Hallucinations and delusions = reality distortions e.g. thought insertion, thought withdrawal,
delusions of control. Can occur in any modality, typically auditory (hearing voices) - Negative symptoms = psychomotor poverty, flattened affect
- Disorganised = disorganised behaviour, inappropriate affect
4
Q
What are the criteria for schizophrenia? (According to the DSM)
A
Criteria A: Characteristic symptoms = 2+ for a month
- Delusions
- Hallucinations
- Disorganised speech
- Grossly disorganised or catatonic behaviour
- Neg symptoms
Criteria B: social/occupational dysfunction
C: Duration (6+months)
D: Schizoaffective/mood disorder exclusion
E: Substance exclusion
F: Relationship to global development delay/autism
5
Q
How does the DSM 5 deal with these categories?
A
- Rates severity from 1-5 inc additional symptoms like impaired cognition
- Severity of depression and mania taken into account
- Goal is to help clinicians and researchers - recommended
- Criticism of going for high reliability at the expense of validity
6
Q
What are diagnostic controversies pt 1?
A
- Ignores cognitive symptoms despite
- Decreased IQ, loss of recall/recog memory and EF and Problems with attention, info processing, eye movement
- Lack of clear distinctions between various types as subtypes have poor diagnostic stability over time and >5% research studies on subtypes
- DSM had hierarchical structures for those fitting more than one subtype
- Sep subtypes not supported genetically
- Key diagnostic features cannot be measured objectively
- Needs to break down some categories
- Cog changes not added to list of symptoms despite prominence
7
Q
What are the subtypes?
A
- Disorganized type - where thought disorder and flat or inappropriate affect are present
together - Paranoid type - where delusions and hallucinations are present but thought disorder,
disorganized behaviour, and affective flattening is absent - Catatonic – odd fixed postures, negative symptoms
- Undifferentiated type - psychotic symptoms are present but the criteria for paranoid,
disorganized, or catatonic types has not been me
8
Q
What are the risk factors for Schiz/Psychosis?
A
- Gender: males
- Social Class: lower socioeconomic status
- Urbanisation: rates increase as you get closer to city center
- Immigrant groups: unusually high rates in immigrant groups: London rates vary with proportion of ethnic minority in area
9
Q
What are the Perinatal Risk Factors?
A
- Link with winter births/viral events
- Stress in pregnancy – 67% increased risk of schiz in offspring exposed to ++stress when inutereo
- Risk signs include low birth weight, pre-eclampsia
- Perinatal complications: complications of pregnancy, abnormal fetal growth, complications of delivery
- Perinatal effect remains after SES accounted for
- Birth complications more common in schiz member of
discordant twin - Rhesus (Rh) Incompatability: Rh –ve mother and Rh-+fetus =
increased risk of schiz
10
Q
How can childrearing env affect schiz?
A
- A typical communication in family - higher verbosity and vagueness
- Expressed emotion – Number of critical comments- hostility, over concern, overprotectiveness. = EE higher relapse rates
❖ ‘Double bind’ theory of parent-child communication. Where a person gets 2 contradictory messages and is prevented from talking about the contradiction = could lead to people feeling ‘insane’, uncertain
11
Q
What are issues with assigning childrearing env to schiz?
A
- Problems of studying family interactions = bidirectional effects – cause/effect issues,
retrospective designs, control group - Childhood Adversity, Maltreatment and Abuse: Over the last two decades a growing body of research has highlighted the potentially causal role that childhood trauma may play in the development of psychosis/schiz
12
Q
What is the role of expressed emotion in schiz?
A
- Low EE families can be protective, but high EE can impose additional stress and affect relapse
13
Q
What is a neurodevelopmental perspective?
A
- Evidence of lengthy period of abnormality prior to diagnosis - ‘prodromal’ state e.g. longer to
walk, more speech problems, low educational scores at 8, 11, 15, solitary play preferences. - Home videos of adults with schiz and a non-schiz sibling show more neuromotor problems, less +ve facial expressions, odd hand positions
- 50k+ Male Swedish army conscripts assessed prior to Dx. Found fewer than 2 friends; prefer socialising in small groups; more sensitive than other people; no
steady girlfriend; ever used drugs (incl. cannabis); low IQ - Similar study of Israeli army
and found deficits in social function, low IQ, lack of organisation ability
14
Q
What is the role of recreational drug use in Schiz?
A
- Cannabis linked to increased Schiz
- Longitudinal study in NZ: early use by 15yo led to greater risk 10.3% had psychosis/schiz = heavy use by 18 associated with 6x risk increase
- Meta-analysis found that those who used cannabis in adolescence but not alcohol had earlier onset symptoms
- Increases risk but cannabis use also associated with worse outcomes = more admission for longer periods
15
Q
What is the role of genetics in schiz?
A
- Concordance rates for schiz increases the more genes you share with that person
- Twin studies show people can have an unexpressed schiz gene
- MZ twins have the same percentage of schiz, but this is much smaller in DZ twins
