Psychotic Disorders

Psychosis is the misrepresentation of thoughts and perceptions that originate from a patient’s own mind which are experienced as reality. It is a symptom, not a diagnosis in itself and affects about 3% of the population.

Causes: With most psychiatric conditions, the aetiology of psychosis is seen with a biopsychosocial model:

Biological:

Genetics –> Twin studies have shown schizophrenia has 50% concordance rate in MZ  twins

Dopamine–> Antipsychotics block D2 receptors whereas L-Dopa induces psychosis

Neurodevelopmental –> Higher in people with low birth weight, developmental delay etc.

Psychological:

Prodrome –> Often preceded by patients exhibiting anxiety, depression and ideas of reference

– These people can be offered CBT to reduce risk of progression to full psychosis

Social:

Stress –> Linked to social deprivation, urbanisation and stressful live events

Schizophrenia

This is the most famous psychotic condition which was originally called “Dementia Praecox” by Kraepelin.

– It is more frequent in men typically arising before the age of 40 and is linked with the risk factors above

In a nutshell, the main problems of schizophrenia for patients (symptoms and side effects) can be conceptualised by looking at the dopamine pathways in the brain. There are 4 main dopaminergic pathways in the brain:

Mesolimbic (VTA to NAc) –> This is involved in the reward pathway and attributing salience to a stimulus

– Excessive dopamine activity here is thought to give positive symptoms: delusions, hallucinations etc.

Mesocortical (Pre-frontal cortex) –> Dopamine here is important for executive functioning, emotion, speech

– Underactive dopamine here is thought to give negative symptoms: alogia, anhedonia, blunted affect

Nigrostriatal (SNr to Basal Ganglia) –> Dopamine here increases voluntary motor movements

– Therefore, explains why anti-psychotics (D2-blockers) lead to extrapyramidal symptoms

Tuberoinfundibular (to anterior pituitary) –> Dopamine here is responsible for reducing prolactin output

– Explains why anti-psychotics (D2-blockers) elevate prolactin release giving hyperprolactinaemia

Symptoms: These can mostly be divided into positive and negative symptoms

a) Positive – This is defined as symptom that is present through its presence

• Hallucinations – This is a perception which the patient experiences as coming from the outside world

– However, it occurs in the absence of an external stimulus

– The most common are 3rd person auditory hallucinations or voices giving running commentary

• Delusions – A false belief out of keeping with the patient’s sociocultural background

– This is held with unshakeable conviction even in the face of contradictory evidence

– Most common is persecutory –> the belief that people are conspiring against you

– Delusions of reference –> the belief that people on TV/radio are talking to/about you

• Thought Disorder – an impaired capacity to sustain coherent discourse, in written or spoken language

• Catatonia – These are abnormal movements experienced by some patients:

– Waxy flexibility (you can move a patient into a position and they will remain frozen there)

– Catatonic stupor (this is where a patient suddenly stops and stays there)

• Passivity Phenomena – This is the belief that your thoughts/actions are no longer your own

– Includes thought insertion (something putting a thought into your head), thought broadcasting (everyone can read your thoughts) and thought withdrawal.

b) Negative – This is defined as symptom that is present through its absence. Remember by 5A’s:

– Affect blunted = restricted emotion with poor emotional display

– Alogia = paucity of speech

– Asociality = social isolation

– Anhedonia = Lack of pleasure

– Avolition = Lack of motivation

Diagnosis: The DSM-5 needs >2 of the following experienced for 1 months. At least 1 should include 1-3:

1. Delusions
2. Hallucinations
3. Disorganised speech
4. Disorganised or catatonic behaviour
5. Negative symptoms

Hebephrenic/Disorganised – This has early onset, with unpredictable behaviour and speech

– Affect and mood is inappropriate with giggling, mannerisms and pranks

– Patients can also have fleeting hallucinations and delusions

Residual – A long-term subtype where most symptoms have gone but the negative symptoms remain

Undifferentiated – cannot be classified into any of the other subtypes 

Management – The primary management will be oral antipsychotics in a staged approach

i) Antipsychotics –> 1st line is oral atypical anti-psychotics (quetiapine, olanzapine, risperidone)­­­

–> 2nd line is oral typical anti-psychotics (haloperidol, chlorpromazine etc.)

–> 3rd line is clozapine, only used for psychosis refractory to other treatments

When prescribing antipsychotics, must regularly monitor weight, lipids and glucose and ECGs:

– Always start at the minimum dose with monotherapy and then titrate up the medication

– Minimum length of treatment is 6 months

– For single episode (medicate for 6-24 months)    

– 2nd is 5 years medications     

– 3rd is life-long medication

ii) Psychotherapy –> CBT is offered to all patients, helps to challenge delusions and develop coping strategies

iii) Social support –> Need social support for appropriate housing, financial advice 

Delusional Disorder

This is a rare mental illness in which a patient experiences delusion, but with no accompanying hallucinations, thought disorder, mood disorder or flattening of affect.

Diagnosis:

Patient must show delusions in absence of any other psychotic symptoms or reversible cause (drugs)

Management:

Psychotherapy (CBT) is main line + Antipsychotics