From the Guidelines
Schizophrenia diagnosis and treatment involve a combination of pharmacotherapies, social support, therapy, psychoeducation, and overall case management.
Diagnosis
The diagnosis of schizophrenia is based on the presence of positive, negative, and cognitive symptoms, which can be assessed using the Positive and Negative Syndrome Scale 1.
- Positive symptoms include hallucinations, delusions, and disorganized behavior
- Negative symptoms include apathy, avolition, and anhedonia
- Cognitive symptoms include impairment of executive functioning, information processing, and attention
Treatment
The primary pharmacological treatment of schizophrenia involves the use of antipsychotics, which can be classified as dopamine D-receptor antagonists or partial agonists 1.
- Antipsychotic monotherapy is the preferred treatment approach, with clozapine reserved for treatment-resistant patients 1
- Clozapine is effective in reducing symptoms in patients who do not respond to non-clozapine antipsychotics 1
- Antipsychotic polypharmacy may be considered in patients who do not respond to monotherapy, but it can cause more side effects 1
- Social support, therapy, psychoeducation, and overall case management are also essential components of schizophrenia treatment 1 In patients with treatment-resistant schizophrenia, clozapine should be tried after two failed monotherapy trials with other antipsychotics 1. If residual symptoms persist, other treatment options, such as antipsychotic polypharmacy or long-acting injectables, may be considered 1.
From the Research
Diagnosis of Schizophrenia
- The diagnosis of schizophrenia is associated with demonstrable alterations in brain structure and changes in dopamine neurotransmission, the latter being directly related to hallucinations and delusions 2
- The reliability of diagnosis has improved with operational criteria, including Diagnostic and Statistical Manual of Mental Disorders, (DSM) Fifth Edition, but the validity of the disease boundaries remains unclear due to substantive overlaps with other psychotic disorders 3
- Symptoms typically emerge in adolescence and early adulthood, and the incidence of the disorder varies greatly across places and migrant groups, as do symptoms, course, and treatment response across individuals 2
Treatment of Schizophrenia
- Comprehensive treatment entails a multi-modal approach, including psychopharmacology, psychosocial interventions, and assistance with housing and financial sustenance 3
- Pharmacological treatments, which block the dopamine system, are effective for delusions and hallucinations but less so for disabling cognitive and motivational impairments 2
- Specific vocational and psychological interventions, in combination with antipsychotic medication in a context of community-case management, can improve functional outcome but are not widely available 2
- Psychosocial interventions such as cognitive-behavioural therapy, cognitive remediation, and supported education and employment have added treatment value, but are inconsistently applied 4
Etiology and Pathophysiology
- The etiology of schizophrenia is now thought to be multifactorial, with multiple small-effect and fewer large-effect susceptibility genes interacting with several environmental factors 3
- These factors may lead to developmentally mediated alterations in neuroplasticity, manifesting in a cascade of neurotransmitter and circuit dysfunctions and impaired connectivity with an onset around early adolescence 3
- Neurochemical disturbance, involving dopamine function and glutamatergic N-methyl-D-aspartate receptor function, is supported by indirect and direct evidence 5
- The genetic contribution to schizophrenia is now recognised to be largely polygenic, and birth and early life factors also have an important aetiological role 5