[8.39/40/41] Schizophrenia

Question 1

what is schizophrenia

Answer 1

psychiatric disorder:
- disturbance of cognitive abilities and behaviours (split understanding of hallucinations from reality)
- prevalent in late-teens to mid-thirties
- > prevalent in men (1.4:1)

Question 2

how is schizophrenia presented?

Answer 2

1. positive symptoms (deluisions, hallucinations, unusual or disorganised behaviour)
2. negative symptoms (lack of interest/activity, unresponsiveness)
3. harm and suicide > common than violent tendencies

Question 3

causes of schizophrenia

Answer 3

genetic + environmental factors; family history

most common:
- premature birth
- low birth weight
- perinatal hypoxia with subtle effects on the brain’s development
- neurodevelopmental hypothesis (social isolation)
- biochemical hypotheses (4)

Question 4

what are the biochemical hypotheses for the causes of schizophrenia?

for sch: what is disturbed?

Answer 4

1. Dopamine hypothesis (dopamine receptor agonism (/overactivity) results in schizo symptoms eg. hallucinations; firing of nigrostriatal [cortical] and mesolimbic [limbic] dopamine pathways causes psychotic symptoms)
2. NMDA receptor hypothesis (NMDA receptor antagonism/dysfunction can cause schizo)
3. Single-Carbon hypo (disturbances of the single-carbon folate pathway linked to schizophrenia; production of purine and pyramidines + methionine)
4. Membrane hypo (deficit in level of highly unsaturated FA: decr fluidity, gap junctions, permeability) + (increased PLPA2 activity - breakdown of membrane phospholipids = potentially impaired transmission of signals)

Question 5

5

symptoms of schizophrenia + descriptions

Answer 5

1. delusions (beliefs appearing real)
2. hallucinations (hearing/seeing/smelling/feeling things)
3. disorganised thinking/speech
4. negative symptoms (social withdrawal, absence of emotion and expression, reduced energy, motivation and anxiety)
5. catatonia (person fixed into a single position for a long period of time)

Question 6

diagnosis of schizophrenia - what needs to be checked off?

Answer 6

at least 1/3 main domains clearly present /
2/3 present less clearly for one month
1. positive psychotic symptoms
2. negative
3. reduced social / occupational functioning

Question 7

12…

differential diagnosis of schizophrenia

Answer 7

1. substance abuse
2. medical conditions (head injury, CNS infection, brain tumour, endocrine problems)
3. mood disorders
4. acute psychotic disorder
5. sleep-related disorders (hypnopompic/hypnagogic)
6. delusional disorder (presence of at least 1 non-bizarre delusion with lack of thought for at least 1 month)
7. dementia + delirium
8. PTSD
9. hypochondriasis
10. OCD
11. PPD (paranoid personality disorder)
12. SPD (schizotypal personality disorder - odd/eccentric behaviour)

Question 8

Treatment: schizophrenia? + pros and cons

Answer 8

1. typical antipsychotics (
   (+) effective symptomatic relief
   (-) s/e: extrapyramidal symptoms eg. violent tremor, bradykinesia, muscle rigidity, acute dystonia; tardive dyskinesia (basically alot of neurological, autonomic and neuroendocrine s/e)
2. atypical antipsychotics (cariprazine, clozapine, olanzapine, quitiepine)
   (+) clozapine: both + and - symptoms; reduction of EPS risk and suicide
   (-) expensive, weight gain, s/e (fever, rapid pulse and respir rate, infection-prone, sore throat, swollen and tender gums)

Question 9

case drug: cariprazine

Answer 9

class: atypical antipsychotic
MOA: D2/D3 partial agonist; overall reduction of dopamine levels
s/e: extrapyramidal symptoms, akathasia, short-term weight gain