Psychotic disorders Flashcards
Schizophrenia defining characteristics
Chronic psychotic disorder
Distortions of thinking and perception
Inappropriate of blunted affects - emotion, language, sense of self and behaviour
Clear consciousness and intellectual capacity maintained (cognitive deficits may evolve)
Psychopath phenomena - thought echo/insertion/withdrawal, broadcasting, delusional perception, delusions of control/influence/passivity, hallucinatory voices, thought disorder and neg Sx.
What is a hallucination
A perception in the absence of external stimulus
What is a delusion
A fixed, false unshakeable belief, despite ration argument/evidence to the contrary; cannot be explained by pts cultural, religious or education background; process by which arises in bizarre and illogical
What is schizophreniform disorder
Psychotic illness with Sx of schizophrenia present for significant portion of time for at least a month, but signs last less than 6 months
Pathophysiology/aetiology/RFs of schizophrenia
Onset 15-45 years; men affected earlier and more severely; rarely presents in childhood and is associated wit developmental delay
Genetics
- FHx biggest RF - esp 1st degree relative
- Likely multiple susceptibility genes
- Adoption studies - children with FHx, still at high risk
Obstetric complications
- Maternal prenatal malnutrition or viral infection
- Pre-eclampsia
- Low birthweight
- Emergency caesarian
Substance misuse
- Cannabis, amphetamines, cocaine, LSD - can produce psychotic Sx
- Cannabis does not cause SCZ; increases risk even more in susceptible
Social disadvantage
- Low socio-economic status
- Not from birth; downward drift due to illness/social isolation/unemployment
Urban life and birth
- Higher prevalence in urban areas
Migration and ethnicity
- 1st+2nd generation immigrant have 3x increased risk
Expressed emotion
- Close contract with highly critical/over-involved relatiuves doubles the risk of relapse in period following discharge
Premorbid personality
- Premorbid schizoid personality predates SCZ in 25% cases
- Schizotypal disorder is associated with schizophrenia
Adverse life experience
- Sexual or physical abuse in childhood or adulthood
COMT in SCZ
COMT enzyme located on chr 22q11 - encodes catechol-O-methyl-transferase involved in dopamine metabolism
Two alleles of COMT - Val and Met- Valine to methionine substitution = less enzyme activity
In SCZ relationship between first age cannabis use and disorder onset is mediated b COMT genotype; Cannabis increases the risk of developing SCZ younger if you have the ValVal genotype. Onset in Met-Met genotype is not really influenced by cannabis.
Schizophrenia theories
Neurodevelopment - Initial brain abnormalities (genetic or early brain damage) + maturation of the brain along with other RFs -> functional and connectivity abnormalities
Neurotransmitter - Dopamine hypothesis - SCZ as a result of dopamine overactivity in certain areas; pos Sx: excess DA in mesolimbic tracts; neg Sx: deficient DA in mesocortical tracts. Evidence: antipsychotics are dopamine antagonists; work better for pos Sx; dopaminergic agents (amphetamine, cocaine, L-dopa) induce psychosis
Psychological - Cognitive models: subtle thinking defects predispose to delusions
Key dopaminergic pathways of the brain
Mesolimbic
- Projections from ventral tegmental area (VTA) in midbrain to ventral striatum (includes nucleus accumbens and olfactory tubercle)
- Involved in feelings of pleasure and reward
- Thought to play a role in pos Sx of SCZ
Mesocortical
- Projections from VTA to prefrontal cortex
- Involved in cognition and executive function (dorsolateral prefrontal cortex), and emotions and affect (ventromedial prefrontal cortex)
- Though that hypofunction of this pathway leads of cognitive and negative Sx of of SCZ
Nigrostriatal
- Projections from substantia nigra pars compacta (SNc) to caudate nucleus and putmen (both in dorsal striatum)
- Contains ~80% of DA in the brain
- Involved in motor planing and stimulating purposeful movement
- D2 anatagonists i.e. typical antipsychotics, can interfere with this pathway to cause extrapyramidal Sx.
Tuberinfundibular
- Projections from arcuate and periventricular nucleus of hypothalamus to the infundibular region of hypothalamus, specifically the median eminence
- DA released into portal circulation which connects to the pituitary; DA acts to inhibit prolactin release
- D2 antagonists can prevent this function causing hyperprolactinaemia -> can affect menstrual cycle, libido, fertility, bone health or cause galactorrhoea
Clinical stages of SCZ: Prodrome
At-risk mental state (ARM) before SCZ
Low grade Sx: social withdrawal, loss of interest in work, study, relationships
No frank psychotic Sx
Pts usually in late teens/early 20s
May have dropped out of college or work after a period of increasing absences
My seem distant with no reason for isolating themselves
Stages of SCZ: Acute phase
Mainly positive Sx (neg Sx may also be present)
Auditory hallucinations
Delusions
Overvalued idea - firmly held belief which itself is acceptable/comprehensible, but dominates thinking/behaviour
Thought interference - withdrawal/insertion/broadcast
Formal though disorder - may be disjointed, hard to follow; poverty of thought and though blocking may occur
Depersonalisation - feels unreal, detached, numb, emotionally distant
Derealisation - world feels unreal
Types/examples of auditory hallucinations in SCZ
Voices discussing or arguing about the patient ‘no one likes her’ ‘yea its because shes ugly’ ‘
Voices giving a running commentary ‘now hes falling asleep’ ‘now hes calling a cab’
Thought echo ‘the voices day the patients own thoughts out loud
Types of delusions in SCZ
Primary delusion: appear suddenly, no explanation for them
Secondary delusion: manifests as an attempt to explain strange experiences
Persecutory: belief someone wants to harm them (common)
Erotomanic: belief someone is in love with them
Grandiose: belief they have superior abilities/qualities
Somatic
Nihilistic: belief pt is dying, homeless or they are rotting (absence of something important)
Delusions of reference: beliefs that ordinary objects/events/actions have a significant meaning
Delusions of jealousy
Delusions of guilt
Hypochondriacal delusions: belief they have an illness
Idea of reference: belief that events relate to them personally
Delusional perception: real perception interpreted in delusional way
Passivity: belief that movement/sensation/emotion/impulse are controlled by an outside form
Thought disorders in SCZ
Circumstantiality: gives excessive unnecessary detail, but eventually returns to the original point
Tangentiality: wandering from a topic without returning to it
Neologisms: new word formations, might include combining two words
Clang associations: ideas are related only by the fact they sound similar or rhyme
Word salad: completely incoherent speech where real works are strung together into nonsense sentences
Loosening of associations/derailment: going from one idea to the other, without link
Knights move thinking: severe type of loosening of associations, where there are unexpected and illogical leads from one idea to another
Flight of ideas: leaps from one topic to another but with discernible links between them
Perseveration: repetition of ideas or words, despite attempt to change the topic
Echolalia: repetition of someones speech, including the question that was asked
Stages of SCZ: Chronic phase
Negative Sx reflecting things that are lost in SCZ
Apathy - loss of motivation
Blunted/flat affect - decreased reactivity to mood
Anhedonia - inability to enjoy interests/activities
Social withdrawal
Poverty of thought and speech
May manifest as a lack of attention to personal hygiene/care, reduced repertoire of activities and social isolation
Schneider’s first rank Sx
Delusional perception
Passivity
Delusions of thought interference
Auditory hallucinations: echo, third person, running commentary
Dx of SCZ
2 of more of following Sx for at least one month (including at least one of top 3):
- Delusions
- Hallucinations
- Disorganised speech
- Grossly disorganised or catatonic behaviour
- Negative Sx such as diminished emotional expression
Impairment in one of the major areas of functioning for a significant period of time since onset: work, interpersonal relations, self-care
Some signs of disorder must last for a continuous period of at least 6 months - including at least one month of criterion A Sx and periods of residual negative Sx
Schizoeffective, bipolar, depressive disorder with psychotic features excluded
Associated features that may contribute to Dx: Inappropriate affect Disturbed sleep pattern Dysphoric mood Anxiety and phobias Depersonalisation Cognitive defects Lack of insight Social cognition deficits Hostility and aggression
Subtypes of schizophrenia
Paranoid: Most common; prominent hallucinations an d (usually persecutory) delusions
Catatonic: Psychomotor disturbance
- Stupor - immobile, mute, unresponsive, but conscious
- Excitement - periods of extreme+purposeless motor hyperactivity
- Posturing - assuming and maintaining inappropriate or bizarre positions
- Rigidity - holding a rigid posture against efforts to be moved
- Waxy flexibility - limbs offer minimal resistance to being placed in odd positions, maintained for long (cataplexy)
- Automatic obedience
- Perseveration - inappropriate repetition of words or movements
Hebephrenic
- Usually between 15-25 years
- Disorganised and chaotic mood, behaviour and speech; aimless behaviour; child like
- Shallow or inappropriate affect
- Delusions/hallucinations less prominent
Simple
- Negative features only, never having never shown pos Sx
Residual
- Prominent neg Sx that remain after delusions and hallucinations subside
Investigations fro SCZ
Full exam&Ix to exclude organic causes
Establish baseline health before starting Tx
Bloods - FBC, TFT, U&E, LFT, CRP, fasting glucose, + lipids before starting antipsychotics
MSU, urine drug screen
CT/EEG - to rule our organic pathology, epilepsy, etc, if suspected
Sx rating scales to assess severity an monitor Tx response
OT assessment of Activities of Daily Living
Social work assessment of housing, finances, carers needs
Collateral Hx
Differentials of SCZ
Organic causes
- Substance misuse - alcohol intox/withdraw, amphetamine, cocaine, LSD, ecstacy, ketamine, phencyclidine
- Dementia
- Delirium
- Epilepsy esp temporal lobe epilepsy
- Med side effects - e.g. steroids, Dopamine agonists
- Others: brain tumour, stroke, HIV, Wilsons disease, porphyria, neurosyphilis
Acute and transient psychotic episode
- Resolves completely within a few months
- May be stress related
Mood disorder
- Depression and mania, if severe can cause psychotic Sx
- Don’t Dx SCZ in presence striking mood disturbance unclear cleat that SCZ Sx came first
Schizoaffective disorder
- Dx if both SCZ and affective Sx develop together and are roughly evenly balanced
Persistent delusional disorder
- Delusions with few if any hallucinations
Schizotypal disorder
- Lifelong state of eccentricity with abnormal thoughts and affect; sometimes regarded as personality disorder
- Suspicious, cold and aloof with odd ideas without showing definite SCZ Sx
- Some eventually develop SCZ
NICE guidelines - 1st ep psychosis
EIS - assess asap, ?CR/HTT
Assess in secondary care - Full psych, PMH, risk assessment, phys exam, psychological/social, developmental Hx, social, occupation/education, QoL, economic status; also assess for PTSD
1st line Tx: offer oral antipsychotic + family psych intervention + individual CBT
- Baselines Ix before meds, incl.: weight, waist, HR, BP, glucose, lipid, prolactin, assessment of movement disorders, nutrition, activity, ECG
- Low dose then titrate up over 4-6wks
- Monitoring: Tx response, side effects, movement disorders + compare all baseline check ups + adherence
Subsqeuent: Refer to CRT/HTT
Antipsychotics: classes and examples
Dopamine antagonists that block post-synaptic D2 receptors
Typical antipsychotics: Older drugs
- Chlorpromazine: associated with skin photosensitivity - advise sunscreen
- Haloperidol
- Flupentixol decanoate: depot
- Cause extra-pyr SEs at normal doses
- Effective, cheap, provide long acting depot options
Atypical antipsychotics: in addition, also block serotonin 5-HT2 receptors
- Olanzapine
- Risperidone (avail as depot)
- Quetiapine
- Aripoprazole - partial D2 R agonist - good choice is side effects, unless tardive dyskinesia; ok in low dose for hyperprolacin pt
- Clozapine
- Amisulpride
- Consider when: choosing 1st line Tx for new Dx SCZ, side effects from typicals, relapse on typicals
- Metabolic side effects more prominent
Antipsychotics: side effects
Extrapyramidal side effects can occur at higher concentrations of all antipsychotics, but are less common with atypicals
Extrapyramidal
- Dystonia
- Akathisia
- Parkinsonism
- Tardive dyskinesia
Hyperprolactinaemia
- Galactorrhoea, amenorrhea, gynaecomastia, hypogonadism
- Sexual dysfunction
- Increased risk of osteoporosis
Metabolic syndome
- Weight gain (especially olanzapine and clozapine)
- Increased risk of diabetes
- Dyslipidaemia
Sedation
Reduced seizure threshold (greater with atypicals); dose-dependent effect
Anticholinergic side effects
- Dry mouth, blurred vision, constipation, urinary retention, tachycardia
- Less often with aripiprazole and risperidone
Arrhythmias
- Associated with prolonged QTc; if >500ms - stop anti-psych, urgent cardio referral; if <500ms, but still abnormal - consider decreasing dose/switching drug, repeat ECG, refer to cardio if still abnormal
- Particularly haloperidol
- Aripiprazole safest
Increased appetite: olanzapine
Neuroleptic malignant syndrome
Neuroleptic Malignant Syndrome: what is, Sx, Bloods, Tx
Rare, but life-threatening medical emergency, as side effect of antipsychotic
Usually triggered by new antipsychotic or dose increase
Thought to be idiosyncratic response to DA antagonism -> acute dysreg of CNS NTs
Symptoms:
- Muscle stiffness and rigidity
- Altered consciousness
- Disturbance of Autonomic NS (fever, tachycardia, labile BP)
Raised CK and WCC
Tx:
- Stop antipsychotic immediately
- Urgent med Tx - Fluids to prevent AKI, cooling measures if hyperthermia, lorazepam if agitation and catatonia, ECT in severe cases
- Benzo: lorazepam/diazepam; 2. Dantrolene: skeletal muscle relax for malignant hyperthermia; 3. Bromocriptine (/Amantadine) DA agonist
Death may be from several causes e.g. rhabdomyolysis leading to renal failure
Monitoring with antipsychotics
BMI and waist circumference
BP
FBC, LFT, U&E, glucose tolerance (or fasting/HbA1c), lipids
Some may need: prolactin levels, ECG
