Schizophrenia
Summary
Schizophrenia is a chronic, severe mental disorder characterised by disturbances in thought, perception, behaviour, and affect. It typically presents with positive symptoms (hallucinations, delusions, disorganised thinking) and negative symptoms (flat affect, avolition, social withdrawal). Cognitive impairment is common and often precedes the first psychotic episode. Treatment is lifelong, centring on antipsychotic medication (oral or depot) combined with psychological therapies (CBT for psychosis, family interventions). Clozapine is reserved for treatment-resistant schizophrenia. Early intervention in psychosis significantly improves outcomes.
Key Facts
- Definition: Chronic psychotic disorder with ≥2 characteristic symptoms for ≥6 months
- Prevalence: ~1% lifetime risk
- Onset: Late adolescence to early adulthood (males ~18-25; females slightly later)
- Positive Symptoms: Hallucinations (auditory), delusions, disorganised thought/speech
- Negative Symptoms: Flat affect, avolition, alogia, anhedonia
- First-Line Treatment: Oral antipsychotic + psychological therapy
- Treatment-Resistant: Clozapine (after 2 adequate antipsychotic trials fail)
Clinical Pearls
"Treat Early, Treat Effectively": Duration of untreated psychosis (DUP) predicts outcomes. Shorter DUP = better prognosis.
"Clozapine Saves Lives": Treatment-resistant schizophrenia (30%) requires clozapine — the most effective antipsychotic. Don't delay referral.
"Metabolic Monitoring is Essential": Antipsychotics cause weight gain, diabetes, dyslipidaemia. Monitor and manage cardiovascular risk.
Why This Matters Clinically
Schizophrenia is a leading cause of disability worldwide. Untreated or poorly treated schizophrenia leads to relapse, hospitalisation, social isolation, and premature death (20-year reduced life expectancy, mainly from cardiovascular disease and suicide).
Prevalence
| Measure | Value |
|---|---|
| Lifetime Risk | ~1% |
| Point Prevalence | 0.3-0.7% |
| Incidence | 15 per 100,000/year |
Demographics
| Factor | Details |
|---|---|
| Age of Onset | Males 18-25; Females 25-35 |
| Sex | Equal prevalence; males earlier onset, worse outcomes |
| Ethnicity | Higher incidence in migrants, urban dwellers |
Risk Factors
| Factor | Details |
|---|---|
| Genetic | 80% heritability; 10% if first-degree relative |
| Obstetric Complications | Hypoxia, infection, stress |
| Cannabis Use | 2-6x increased risk (especially adolescent, high-THC) |
| Urban Living | 2x risk vs rural |
| Migration | 2-3x risk |
Dopamine Hypothesis
- Mesolimbic Hyperactivity → Positive symptoms
- Mesocortical Hypoactivity → Negative and cognitive symptoms
- Antipsychotics block D2 receptors (reduce positive symptoms)
Glutamate Hypothesis
- NMDA receptor hypofunction
- Explains negative and cognitive symptoms
Neurodevelopmental Model
- Abnormal brain development (prenatal/perinatal insults)
- Synaptic pruning abnormalities in adolescence
- Structural changes: Enlarged ventricles, reduced grey matter
Positive Symptoms
| Symptom | Details |
|---|---|
| Auditory Hallucinations | 3rd person, running commentary, command |
| Delusions | Persecutory, reference, control, grandiose |
| Disorganised Thought | Tangentiality, derailment, thought blocking |
| Disorganised Behaviour | Unpredictable, inappropriate |
Negative Symptoms
| Symptom | Details |
|---|---|
| Flat Affect | Reduced emotional expression |
| Avolition | Lack of motivation |
| Alogia | Poverty of speech |
| Anhedonia | Inability to experience pleasure |
| Asociality | Social withdrawal |
Red Flags
[!CAUTION] Red Flags:
- Suicide risk (10% lifetime)
- Violence risk (rare; assess command hallucinations)
- Catatonia
- First episode psychosis
- Non-adherence
Mental State Examination
| Domain | Findings |
|---|---|
| Appearance | Poor hygiene, neglect |
| Behaviour | Agitation, stereotypies, catatonia |
| Speech | Poverty, pressure, neologisms |
| Mood | Incongruent affect, flat |
| Thought Form | Loose associations, derailment |
| Thought Content | Delusions, ideas of reference |
| Perception | Auditory hallucinations |
| Cognition | Impaired attention, working memory |
| Insight | Often poor |
| Test | Purpose |
|---|---|
| FBC, U&E, LFTs | Baseline, organ function |
| TFTs | Exclude thyroid cause |
| HbA1c, Lipids | Metabolic baseline |
| Urine Drug Screen | Exclude substance-induced psychosis |
| CT/MRI Brain | First episode to exclude organic cause |
| ECG | Baseline before antipsychotic (QTc) |
Pharmacotherapy
First-Line: Oral antipsychotic (aripiprazole, risperidone, olanzapine)
Depot (LAI): If adherence concerns
Treatment-Resistant: Clozapine (after 2 failed trials)
Psychological Therapies
- CBT for psychosis (CBTp)
- Family intervention
- Art therapies
- Vocational support (IPS)
Physical Health
- Metabolic monitoring
- Smoking cessation
- Cardiovascular risk management
| Complication | Notes |
|---|---|
| Relapse | Common with non-adherence; depot reduces risk |
| Suicide | 10% lifetime risk |
| Substance Misuse | 50% comorbidity |
| Metabolic Syndrome | Weight gain, diabetes, CVD |
| Reduced Life Expectancy | 15-20 years shorter (CVD, suicide) |
| Social Isolation | Unemployment, relationship breakdown |
Course
| Pattern | Notes |
|---|---|
| Rule of Thirds | 1/3 recover, 1/3 partial recovery, 1/3 chronic |
| First Episode | 80% remit; 80% relapse within 5 years if untreated |
Prognostic Factors
| Good | Poor |
|---|---|
| Acute onset | Insidious onset |
| Later age of onset | Young male |
| Good premorbid functioning | Pre-existing cognitive impairment |
| Predominant positive symptoms | Predominant negative symptoms |
| Good treatment adherence | Cannabis use |
| Short DUP | Long duration of untreated psychosis |
Key Guidelines
- NICE CG178: Psychosis and schizophrenia in adults (2014)
Landmark Trials
CATIE (2005) — Antipsychotic comparison
- Key finding: Olanzapine most effective but highest metabolic burden
- Clinical Impact: Side effect profile guides choice
CUtLASS (2006) — FGA vs SGA
- Key finding: No clear superiority of SGAs over well-chosen FGAs
What is Schizophrenia?
Schizophrenia is a long-term mental health condition that affects how you think, feel, and behave. It can cause symptoms like hearing voices that others don't hear, believing things that aren't true, or feeling emotionally flat.
What are the symptoms?
- Hearing voices (hallucinations)
- False beliefs (delusions)
- Confused thinking
- Lack of motivation
- Difficulty with emotions and social connections
How is it treated?
- Medication: Antipsychotic tablets or injections help control symptoms
- Talking therapies: CBT helps you cope with symptoms
- Support: Family therapy, employment support, social skills training
What to expect
- Most people improve with treatment
- Medication is usually needed long-term
- With support, many people live fulfilling lives
Primary Guidelines
- National Institute for Health and Care Excellence. Psychosis and schizophrenia in adults: prevention and management (CG178). 2014. nice.org.uk/guidance/cg178
Key Trials
- Lieberman JA, Stroup TS, McEvoy JP, et al. Effectiveness of antipsychotic drugs in patients with chronic schizophrenia (CATIE). N Engl J Med. 2005;353(12):1209-1223. PMID: 16172203
Further Resources
- Rethink Mental Illness: rethink.org
- Mind: mind.org.uk
Medical Disclaimer: MedVellum content is for educational purposes and clinical reference. If you are experiencing psychosis or mental health crisis, please seek help immediately.