Psychotic disorders Flashcards
Definition of hallucinations, delusions, formal thought disorder
Hallucinations = perceptions without external stimulus
Delusions = fixed, false beliefs, held despite rational argument or evidence to the contrary. These can’t be explained by pt’s cultural, religious, or educational background.
Formal thought disorder = illogical/muddled thinking; people may experience this as struggling to think clearly
Psychotic disorder epidemiology
0.7% lifetime risk schizophrenia (3% any psychotic disorder)
late adolescence to early 20s usually
m:f 3:2 (men usually affected earlier and more severely)
Schizophrenia aetiology
Genetics = first-degree relatives, high heritability, multiple susceptibly genes
Obstetric complications = maternal prenatal malnutrition, viral infections, stress, analgesic use and obstetric hypoxia conditions (e.g. pre-eclampsia, C-section) and foetal growth retardation
Childhood adversity
Social disadvantage
Urbanicity = 2x more prevalent in urban
Migration and ethnicity= 1st + 2nd gen migrants higher risk, higher in black Caribbean and black African
Associated conditions = schizoid personality precedes schizophrenia 25% of time , schizotypal disorder more commonly associated with schizophrenia, possibly due to a shared genetic basis
Substance use disorders
- drug-induced psychosis = cannabis, amphetamines, cocaines and NPS
- can trigger relapse
- skunk (form of weed that has more THC) in teen increases risk of later developing schizophrenia
Neurotransmitter theory for psychotic disorders
positive sx’s (hallucination and delusion) = excess dopamine
negative sx’s (apathy, social withdrawal) = dopamine under activity
all known effective antipsychotics are dopamine antagonists (dopamine receptor blockers)
- work better for +ve than -ve sx’s
- dopaminergic agents (amphetamine, cocaine, L-dopa, bromocriptine can all induce psychotic sx’s)
- glutamate transmission effects dopamine transmission = PCP and ketamine cause schizophrenia-like psychosis by blocking glutamate transmission t NMDA receptors
Atypical antipsychotics are effective serotonin antagonists
3 stages of psychotic disorders
at-risk mental state (ARMS), acute phase, chronic phase
ARMS
20-30% with ARMS develop psychosis , half meet criteria for schizophrenia
period of very mild/brief psychotic sx’s, change in function (social withdrawal, loss of interest in activities, or mood sx)
e.g. late teens/early 20s dropped out of work or education after a period of increasing absence, may seem distant, isolating themselves in bedroom without giving reasons. May deny emerging psychotic sx for fear of their significance → psychosocial tx with CBT and family intervention recommended
hard to distinguish from depression, substance misuse, or ‘normal’ teenage behaviour
Acute phase
striking +ve symptoms
- delusions (usually persecutory)
- hallucinations (usually auditory)
formal thought disorder common = thoughts muddles speech disorganised, vagueness to disjointed speech that’s hard to follow and senseless
- thought blocking
behaviour = withdrawn, overactive, bizarre
may have a number of acute psychotic episodes over the years, with full or partial recovery between relapses
chronic phase
develop disabling -ve sx
- apathy
- blunted effect = decreased reactivity of mood
- anhedonia
- social withdrawal
- poverty of thought and speech
behaviour = self-neglect, social isolation, inactivity or withdrawal
may be residual and less prominent +e sx’s (e.g. persecutory delusions but seem less distressed and affected by them)
depression and antipsychotics side effects associated with -ve sx’s
often much easier to treat, don’t overlook them since tx can give someone a new lease of life
Schneider’s first rank symptoms
Auditory hallucinations
- running commentary on person’s actions
- third person voice
- thought echo
Thought withdrawal, insertion and interruption
Thought broadcasting
Somatic hallucinations
Delusional perception
Feelings or actions experiences as made or influenced by external agents
Organic causes
Dementia or delirium = especially in elderly patients
Medication side effects = steroids, dopamine agonists, levetiracetam (anticonvulsant aka Keppra)
Cerebral pathology = stroke, SOL, encephalitis, epilepsy, MS, cerebral lupus, HIV, neurosyphilis
Systemic illness = Wilson’s disease, porphyria, Cushing syndrome, hypo/hyperthyroidism
Drug use = amphetamine, cocaine/crack cocaine, LSD, ecstasy, ketamine, GHB/GBL, PCP and many NPS
Alcohol
- alcoholic hallcuinosis
- delirium tremens
Non-organic causes (‘functional psychosis’)
Schizophrenia = sx present for at least a month, affect multiple areas of mental state. May be psychomotor disturbances such as catatonic sx’s. Shouldn’t be diagnosed in the presence of striking mood disturbance.
Acute and transient psychotic disorder = psychotic sx’s occur suddenly and relatively briefly. Peak within 2 weeks and resolve within a month (max duration 3 months). Sx’s fluctuate rapidly, and may be acutely disabling. Not diagnosed if hx of another psychotic illness e.g. schizophrenia
Schizoaffective disorder = schizophrenia picture with mood disorder (moderate/sever depressive or mania) developing simultaneously.
Delusional disorder = delusions lasting more than 3 months, without a clear mood disturbance and lacking other schizophrenia sx’s such as thought disorder, persistent hallucinations, or negative sx’s
Schizotypal disorder = enduring state lasting years (actually a personality disorder). Eccentricity is central to diagnosis. May experience low-level or fleeting delusions or hallucinations. Risk of developing schizophrenia increased.
Puerperal (postpartum) psychosis = psychosis triggered by childbirth; usually occurs within a few weeks of delivery
Other differentials
PD = consider when lifelong pattern of interpersonal difficulties
- Paranoid PD = prominent detachment and negative affectivity traits, suspiciousness and paranoia
- Schizoid PD = prominent detachment traits, lack of interest in others or social norms (can resemble ARMS or negative sx’s)
Other differentials
PD = consider when lifelong pattern of interpersonal difficulties
- Paranoid PD = prominent detachment and negative affectivity traits, suspiciousness and paranoia
- Schizoid PD = prominent detachment traits, lack of interest in others or social norms (can resemble ARMS or negative sx’s)
- Borderline personality pattern = brief psychotic or psychotic-like sx can occur at times of stress, e.g. hearing voices, paranoia
Subtypes of schizophrenia (remember the most common one and its features)
see picture
Schizophrenia: At least ONE of the following
see below
Schizophrenia: at least TWO of the following
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