psychiatry Flashcards
what is delirium
a psychiatric manifestation of a physical illness
a stroke in which part of the brain causes post stroke psychosis
right middle cerebral artery, affecting the frontal and temporal lobes
common symptoms of post stroke psychosis
delusions of a persecutory or jealous type
auditory or visual hallucinations
the 2 types of perception abnormalities
altered perception - distorted internal perception of a real external object
false perception - internal perception without a real external object: hallucination
how does a critical illness cause delirium
critical illness causes increase in cortisol and cerebral hypoxia
which causes decrease in acetylcholine and dysfunction of hippocampus or neocortical areas (increase in dopamine and adrenergic responses)
why should antipsychotics not be used in those w with dementia
they increase the risk of stroke
what is the mortality gap
those with chronic mental illnesses are more likely to experience all round mortality
because they
may experience side effects from drugs
may be more likely to smoke, drink, take drugs
may have poorer diet or exercise
may have lower socioeconomic status
contrast the selectivity and adverse effects of citalopram and amitriptiline and what kind of drugs are they
serotonin reuptake inhibitors
amitriptiline
- trycyclic structure
- less selective
- many adverse side effects due to histamine and noradrenaline receptor blockade
citalopram
- selective
- adverse affects solely due to increase in serotonin
contrast the selectivity and adverse effects of haloperidol and clozapine and what kind of drugs are they
antipsychotics
clozapine
- non selective
- many adverse effects eg weight gain, metabolic syndrome, sedation
haloperidol
- very selective
- few adverse effects
what is alprazolam
a GABA A positive allosteric modulator
what is Baclofen
a GABA B agonist
positives and negatives of psychedelic treatment
+
non addictive
low psychological and brain toxicity
good therapeutic index
-
dysphoria
anxiety
nausea
headache
false memories
name the 2 main effects of psychedelic treatment
psychological peak
mystical type experience
give some indirect evidence for the monoamine deficiency hypothesis
- low levels of 5HT3 in post mortem brains of those who had committed suicide
- antihypertensive drugs which decrease monoamines can cause depression
- high levels of monoamine oxidase A associated with MDD
- high levels of 5HT3 receptors associated with low mood
- low levels of tryptophan (a type of monoamine) associated with MDD relapse
- clinically useful antidepressants all increase synaptic monoamine concentrations
- monoamine depletion correlates with decrease in mood
- depression related traits are associated with increase in 5-HT2A-receptor
what is the monoamine deficiency hypothesis
the hypothesis that depressive symptoms are caused by low levels of monoamine neurotransmitters such as serotonin, norepinephrine, dopamine
which method was used to find direct evidence of low serotonin in living brains of those who are depressed
do a PET scan of brain with an agonist radioligand (11C - CIMBI - 36)
then give a pharmacological challenge (amphetamine) which will stimulate release of serotonin
then do PET scan again
subtract the densities of each PET scan from, eachother to show how much serotonin was able to be released
what are the 3 biases seen in depression
attention bias - can’t disengage/move attention away from negative things, coordinated by anterior cingulate cortex (ACC)
memory bias - more likely to remember negative memories
perceptual bias - amygdala is more stimulated when see negative faces compared to happy ones
which antidepressants help to decrease recognition of anger/fear
noradrenergic + serotinergic antidepressants
contrast heritability and insight in bipolar vs unipolar (MDD) disorder
insight
unipolar > bipolar
heritability
bipolar > unipolar
what are the core symptoms of depression
anhedonia
anergia
low mood
what are the 3 main domains of MDD
atypical features - increased sleep/appetite, heightened mood reactivity
melancholic features - no mood reactivity, anhedonia, psychomotor retardation
psychotic features - hallucinations, delusions
what are the main biological symptoms of depression
sleep
appetite
libido
contrast a mania vs hypomania episode
mania
- last at least a week
- severe symptoms
- functional impairment
hypomania
- lasts at least 4 days
- mild to moderate symptoms
- no functional impairment
but if there are psychotic symptoms or the pt is hospitalised, its mania no matter how long the symptoms lasted
what is unspecified bipolar disorder
lasts less than 4 days or doesn’t reach specific thresholds for mania / hypomania
DSM diagnosis of depression
at least 2 weeks of low mood + 4/8 of the following
- appetite alterations
- sleep alterations (insomnia / hypersomnia)
- anhedonia
- anergia
- guilt
- suicidal thoughts
- impaired concentration
- pyshcomotor changes (agitation / retardation)
why is it important to differentiate between unipolar and bipolar disorder before treating
if you give antidepressants thinking it’s unipolar but its actually bipolar disorder
- can cause acute manic/hypermanic episodes
- can cause mood episodes
- can worsen long term course of bipolar illness
give some organic/iotrogenic causes of depression
- endocrine
- systemic illness: infection, SLE, cancer
- neurological conditions: parkinsons, MS, alzheimers
- deficiencies: B12, folic acid
- medications
- vascular depression: due to white matter hyperintensities which make the individual more vulnerable to stressors
- post stroke depression: the more frontal the lesion, the more severe the symptoms
what can you see in examination of an opioid addict
collapsed veins / track marks
endocarditis
skin abscesses
hepatitis/ hiv
pneumonia
what can you see in examination of an alcohol addict
jaundice
clubbing
oedema
spider naevi
bruising
ascites
what is given for opioid overdose
naloxone (narcan)
what is taken for opioid abstinence
methadone
buprenorphine
what is taken for alcohol abstinence
acamprosate
what is seen in alcohol withdrawal
delirium tremens
- tremor
- anxiety
- hallucinations
- disorientation
3 main diagnostic criteria for dependance syndrome (fulfilment of only one is sufficient for diagnosis)
- lack of control over substance misuse
- increasing precedence of substance use over other aspects of life
- physiological signs of neuroadaption to the substance
how does alcohol cause anxiolysis (a level of sedation in which a person is very relaxed and may be awake)
increased neurotransmission at GABA-A receptor
how does alcohol cause reward
increased dopamine release in mesolimbic system
how does alcohol cause amnesia
inhibits NMDA-mediated glutamate release
what is somatisation
maladaptive functioning of an organ system without underlying tissue or organ damage
or where the symptoms are disproportionate to the underlying structural cause
why are responses in highly emotional situations different for children compared to adults
pre frontal cortex has not yet fully developed in children
so the more matured limbic and reward systems will take over and affect behaviour more strongly than the immature prefrontal cortex
environmental risk factors for ADHD
low birth weight
premature birth
prenatal smoking exposure
contrast mild, moderate and severe dementia
mild
- can live independently but need help with some tasks
- seem normal to people who haven’t met them before
- can still take part in community activites
- cannot make complex plans/decisions
moderate
- can only do simple household tasks, need help functioning outside the house
- difficulty carrying out activities of daily living
- significant memory loss
- people around them can usually tell
- social judgment is impaired
- difficulty socialising and communicating with others
severe
- completely dependent on others
- fully disorientated in terms of time and place
- completely unable to make decisions
- urinary and faecal incontinence
what is the triad of ADHD
inattention
hyperactivity
impulsivity
behavioural and psychological disturbance of dementia
apathy
sleep changes
mood changes
agitation
aggression
irritability
hallucinations
delusions
what clinical examination is done for dementia
MMSE - mini mental state exam
