Title: Subtyping Schizophrenia by Treatment Response: Antipsychotic Development and the Central Role of Positive Symptoms
year: 2015
Journal: Can J Psychiatry
Volume: 60
Issue: 11
Pages: 515-22
Epubdate: 01/01/2016
date: Nov
Alternate Journal: Canadian journal of psychiatry. Revue canadienne de psychiatrie
ISSN: 0706-7437
PMCID: Pmc4679132
Accession Number: 26720509
Abstract: We have recently proposed a model for subtyping schizophrenia based on antipsychotic (AP) treatment response. Evidence suggests that APs, both old and new, are comparable in terms of efficacy; however, one AP, clozapine, is uniquely effective in one subgroup of patients (that is, those with treatment-resistant schizophrenia [TRS]). This permits us to subdivide schizophrenia into 3 specific groups: AP responsive, clozapine responsive, and clozapine resistant. Here, we integrate this model with current criteria related to TRS and ultraresistant schizophrenia, the latter referred to in our model as clozapine resistant. We suggest several modifications to existing criteria, in line with current evidence and practice patterns, particularly emphasizing the need to focus on positive symptoms. While APs can favourably impact numerous dimensions related to schizophrenia, it is their effect on positive symptoms that distinguishes them from other psychotropics. Further, it is positive symptoms that are central to AP and clozapine resistance, and it is these people that place the greatest demands on acute and long-term inpatient resources. In moving AP development forward, we advocate specifically focusing on positive symptoms and capitalizing on the evidence we have of 3 subtypes of psychosis (that is, positive symptoms) based on treatment response, implicating 3 distinguishable forms of underlying pathophysiology. Conversely, pooling these groups risks obfuscating potentially identifiable differences. Such a position does not challenge the importance of dopamine D2 receptor blockade, but rather highlights the need to better isolate those other subgroups that require something more or entirely different.
Notes: 1497-0015
Can J Psychiatry. 2015 Nov
60(11):515-22.
URL: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4679132/pdf/cjp-2015-vol60-nov2015-515-522.pdf
URI: https://open-access.imh.com.sg/handle/123456789/4788
Authors Address: Consultant, Department of General Psychiatry, Institute of Mental Health, Singapore, Singapore
Assistant Professor, Office of Clinical Sciences, Duke-National University of Singapore Graduate Medical School, Singapore, Singapore
Clinical Fellow, Schizophrenia Division, Centre for Addiction and Mental Health, Toronto, Ontario.
Postdoctoral Fellow, Schizophrenia Division, Centre for Addiction and Mental Health, Toronto, Ontario
Collaborative Researcher, Department of Neuropsychiatry, School of Medicine, Keio University, Tokyo, Japan.
Student, Schizophrenia Division, Centre for Addiction and Mental Health, Toronto, Ontario
Student, Institute of Medical Science, University of Toronto, Toronto, Ontario.
Consultant, Department of Psychiatry, Singapore General Hospital, Singapore, Singapore.
Staff Psychiatrist, Schizophrenia Division, Centre for Addiction and Mental Health, Toronto, Ontario
Assistant Professor, Department of Psychiatry, University of Toronto, Toronto, Ontario.
Professor, Department of Psychiatry, Postgraduate Medical Institute, Lady Reading Hospital, Peshawar, Pakistan
Visiting Professor, Centre for Ageing and Mental Health, Staffordshire University, Staffordshire, England.
Lead, Subspecialty Clinics, Schizophrenia Division, Centre for Addiction and Mental Health, Toronto, Ontario
Professor, Department of Psychiatry, University of Toronto, Toronto, Ontario.
Database Provider: Nlm
language: eng
Appears in Collections:2015




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