Psychosis Flashcards
what is psychosis?
presence of gross impairment of reality testing (e.g., lose touch with reality) as evidenced by delusions, hallucinations, markedly incoherent speech, or disorganised and agitated behaviour without apparent awareness on the part of the patient of the incomprehensibility of their behaviour
what is considered treatment resistant schizophrenia?
no significant improvement in symptoms despite treatment with 2 or more APs from 2 different classes at optimal dose for 6-8 weeks
what is schizophreniform disorder?
1-6 months, same symptoms of schizophrenia, social/occupation function impairment not required
what is schizoaffective disorder?
2 or more weeks of delusions, or hallucinations without mood symptoms + uninterrupted period of illness containing either major depressive or manic episodes with concurrent symptoms diagnostic of schizophrenia
social/occupation functional impairment not required
what is brief psychotic disorder?
1 day to 1 month of 1 or more delusions, hallucinations, disorganised speech
return to premorbid function
what is delusional disorder?
1 or more months of delusions
hallucinations not prominent
function only mildly impaired, behaviour not blatantly bizarre
what is substance induced psychosis?
hallucinations or delusions development during or within 1 month of substance use/withdrawal
what is the duration of untreated psychosis?
time from the manifestation of the first psychotic symptom to initiation of adequate treatment
how does being untreated effect mortality?
risk of death doubles if never treated with AP
what is the medication nonadherence rates of schizophrenia?
50-60%
what are some factors associated with nonadherence?
decreased motivational drive from AP
adverse effects
poor insight into illness
personal attitudes towards treatment
stigma
financial constraints
homelessness
substance use
lack of support
ethnic minority
weak therapeutic alliance
what is the key therapy underlying the pathophysiology of schizophrenia?
dopamine dysregulation
how does serotonin dysregulation contribute to schizophrenia?
serotonin modulates dopamine
where is the origin of the nigrostriatal tract?
substantia nigra
what innervates the nirgrostriatal dopamine tract?
basal ganglia
what is the function of the nigrostriatal dopamine tract?
motor coordination, posture control
what does blocking the nigrostriatal dopamine tract cause?
movement disorders (EPS)
where does the mesolimbic dopamine tract originate from?
midbrain
what innervates the mesolimbic dopamine tract?
limbic areas
what is the function of the mesolimbic dopamine tract?
pleasure, reward, desire, response to stimuli, motivational behaviour
what dopamine tract causes positive symptoms of schizophrenia?
mesolimbic
what is the effect of blocking the mesolimbic dopamine tract?
relief of psychosis
where does the mesocortical dopamine tract originate from?
midbrain
what innervates the mesocortical dopamine tract?
frontal and prefrontal cortex
what is the function of the mesocortical dopamine tract?
cognition, motivation, communication, social functioning, emotional response, problem solving
what are the effects of blocking the mesocortical dopamine tract?
akathisia?
treatment of negative symptoms and depression
what dopamine tract is responsible for the negative symptoms of schizophrenia?
mesocortical
where does the tuberoinfunbular dopamine tract originate from?
hypothalamus
what innervates the tuberoinfunbular dopamine tract?
anterior pituitary gland
what is the function of the tuberoinfunbular dopamine tract?
regulate prolactin release
what is the effect of blocking the tuberoinfunbular dopamine tract?
hyperprolactinemia: gynecomastia, galactorrhea, amenorrhea, hirsutism, weight gain, osteoporosis, sexual dysfunction, ED
what are prodromal features of schizophrenia?
often recognised retrospectively after the diagnosis has been made
reclusive adolescence without close friends
not functioning well in occupational, social and personal activities
markedly peculiar behaviour, abnormal affects, unusual speech, bizarre ideas and strange perceptual experiences
what are the 4 symptom clusters in schizophrenia?
positive symptoms (psychosis)
negative symptoms
cognitive symptoms
mood symptoms
what are the positive symptoms of schizophrenia?
hallucinations
suspiciousness/paranoia
delusions
disturbed thought content
bizarre or disorganised behaviour
thought disorder
what are the negative symptoms of schizophrenia?
apathy, social indifference, loss of emotional connectedness
loss of motivation (avolition)
alogia (poverty of speech)
flat affect
poor self care
psychomotor retardation
what are the cognitive symptoms of schizophrenia?
memory impairment
poor concentration
impaired executive functioning: planning, problem solving
what are the mood symptoms of schizophrenia?
dysphoria, depression
excitement, mania
what are delusions?
fixed beliefs that are not amenable to change in light of conflicting evidence
what are some common themes in schizophrenic delusions?
persecutory, referential, somatic, religious, grandiose
what are hallucinations?
perception like experiences that occur without external stimuli
vivid and clear with the full force and impact of normal perceptions and not under voluntary control
what are the most common hallucinations in schizophrenia?
auditory
what is catatonia?
marked decreased in reactivity to the environment
ranges from resistance to instructions (negativism); to maintaining a rigid, inappropriate or bizarre posture; to a complete lack of verbal and motor responses (mutism and stupor)
can also include purposeless and excessive motor activity without obvious cause (catatonic excitement)
what is alogia?
dysfunction of communication
poverty of speech
what is affective blunting?
dysfunction of affect
reduced range of emotions (perception, experience and expression)
what is asociality?
dysfunction of socialisation
reduced social drive and interactions
what is anhedonia?
dysfunction of capacity for pleasure
reduced ability to experience pleasure
what is avolition ?
dysfunction of motivation
reduced desire, motivation, persistence
which enzyme does smoking induce?
CYP1A2
what are the effects of smoking on AP treatment?
affects metabolism of olanzapine and clozapine
may decrease some ADEs of AP through nicotine-dept activation of DA neurons
what are some risk factors of suicide in schizophrenic pts?
depressive symptoms
young age
high socioeconomic status
high premorbid functioning
early onset
chronic deteriorating course
what lab and diagnostic work up is required in schizophrenia diagnosis?
CBC, serum electrolytes, glucose, BUN, SCr, Ca, Mg, P, LFTs, TSH
screen for syphilis, Hep C, HIV (high risk pts)
ECG
urinalysis and urine tox screen
if appropriate:
- CXR
- CT scan/MRI of head
- lumbar puncture
- sleep deprived EEG
what is the diagnostic criteria for schizophrenia?
2 or more of the following each present for a significant period of time during a 1 month period - at least one of these must be 1, 2 or 3
1. delusions
2. hallucinations
3. disorganised speech
4. grossly disorganised or catatonic behaviour
5. negative symptoms
level of social/occupational functioning is markedly below what is was prior to onset
continuous signs of disturbances persist for at least 6 months
which drugs can induced psychosis?
amphetamine and cocaine use and withdrawal
caffeine
bupropion
cannabis
chloroquine
efavirenz
ketamine
steroids
what is the main scale for measuring schizophrenia symptoms?
PANNS (positive and negative syndrome scale)
what is considered a clinical response on the PANNS?
20-25% decrease = minimally improved
40-50% decrease = much improved
70-80% decrease = very much improved
what are the main receptor targets of antipsychotics?
D2
5HT2A
muscarinic
alpha1
H1
which receptors do 1st generation antipsychotics act on?
D2 receptor antagonism
mixed receptor affinity at alpha, muscarinic, histamine receptors
which receptors do 2nd generation antipsychotics act on?
D2 receptor antagonism
5HT 2a/2C antagonism
mixed receptor affinity at alpha, muscarinic, histamine receptors
which receptors do 3rd generation antipsychotics act on?
D2 receptor partial agonism
5HT 2a antagonism
5HT 1a and 1c partial agonism
what are the major ADEs associated with each generation of APs?
1st gen: movement ADEs (EPS)
2nd gen: metabolic ADEs
3rd gen: akathisia
what is the therapeutic effect of D2 antagonism?
antipsychotic effects
improve positive symptoms
what are the ADEs associated with D2 antagonism?
EPS: parkinsonism, akathisia, dystonic reactions, tardive dyskinesia
elevated prolactin: gynecomastia, amenorrhea, impotence, osteoporosis
sexual dysfunction
what is the therapeutic effect of 5HT 2a/2c antagonism and 1a agonism?
2A and 2C: antipsychotic effect
theoretically improve negative symptoms improve negative symptoms through increased dopamine release in mesocortical pathway
1A: anxiolytic
what are the ADEs associated with 5HT antagonism/agonism in APs?
hypotension
sedation
sexual dysfunction
what is the therapeutic effect of alpha1& antagonism?
none
what are the ADEs associated with alpha1&2 antagonism?
a1: postural hypotension, dizziness, reflex tachycardia, sedation, incontinence, drooling
a2: sexual dysfunction
what are the therapeutic effect of muscarinic antagonism?
none
potentiation of drugs with anticholinergic properties
what are the ADEs associated with muscarinic antagonism?
dry mouth
blurred vision
constipation
urinary retention
confusion/memory disturbances