Schizophrenia

Psychiatry

Overview

Definition

A severe, chronic, and debilitating mental disorder characterized by distortions in thinking, perception, emotions, language, sense of self, and behavior.

Epidemiology

Affects ~1% of the population. Onset is typically late teens/early 20s for men, and late 20s for women.

Etiology & Risk Factors

  • Dopamine hypothesis: Hyperactivity in the mesolimbic pathway (causes positive symptoms) and hypoactivity in the mesocortical pathway (causes negative symptoms).
  • Strong genetic component
  • Neurodevelopmental abnormalities (ventricular enlargement, cortical volume loss)

Clinical Symptoms

  • Positive Symptoms: Hallucinations (most commonly auditory), Delusions (fixed false beliefs, often paranoid/persecutory or bizarre), Disorganized speech (word salad, derailment)
  • Negative Symptoms: Flat affect, Alogia (poverty of speech), Avolition (lack of drive), Anhedonia, Asociality

Clinical Approach

Diagnosis

  • DSM-5 Criteria: ≥ 2 active phase symptoms (at least one must be hallucinations, delusions, or disorganized speech) for ≥ 1 month
  • Continuous signs of the disturbance must persist for ≥ 6 months
  • Must rule out Schizoaffective Disorder, drug-induced psychosis, and medical causes

Management

  • Atypical (Second-Generation) Antipsychotics (e.g., Risperidone, Olanzapine, Aripiprazole, Quetiapine) are first-line to block D2 receptors and manage symptoms
  • Clozapine: Reserved for treatment-resistant schizophrenia (must monitor for agranulocytosis)
  • Psychosocial rehabilitation, family therapy, and supported employment

Complications

  • Significant lifelong disability and unemployment
  • High rates of substance use disorder (especially nicotine/smoking)
  • Decreased life expectancy (due to cardiovascular disease and suicide)