Is it possible to stage schizophrenia? A systematic review

Abstract

Introduction A staging model is a clinical tool used to define the development of a disease over time. In schizophrenia, authors have proposed different theoretical staging models of increasing complexity. Therefore, the aims of our study were to provide an updated and critical view of the proposed clinical staging models for schizophrenia and to review the empirical data that support them. Methods Systematic literature review following PRISMA guidelines. From the PubMed database and backward reference search, a total of 141 records were retrieved, but only 20 were selected according to the inclusion criteria: (a) available in English; (b) participants with schizophrenia ≥ 18 years; and (c) theoretical and empirical research studies intended to develop, validate, and/or improve staging models of schizophrenia. Results Different clinical staging models for schizophrenia were identified, information about the proposed stages was tabulated and presented in the Results section (Tables 1, 2). Most of which include neuroimaging, functioning, and psychopathology, but only two models add objective biomarkers and none include patient point of view. However, few models have been psychometrically tested or used small samples and thus have been validated only partially. In addition, five studies proposed therapeutic interventions according to the stage of the disorder from a theoretical point of view. Discussion In conclusion, it is possible to stage schizophrenia, but the models developed have several limitations. Empirical validation and inclusion of more specific biomarkers and measures of other life areas affected by schizophrenia could help in the development of more valid models.

PsiOvi Staging Model for Schizophrenia (PsiOvi SMS): A New Internet Tool for Staging Patients with Schizophrenia

“…Each population’s member is formed by a string of ‘0s’ and ‘1s’ with a length of 61, which is the total number of possible input variables of the model. The criteria for including/excluding data from the analysis were the subject of our previous systematic review [6] and the team discussion. Each ‘0’ means that the variable will not be present in the model under study, and each ‘1’ means that the variable will be employed for training the model.

Figure 1. Flowchart of the algorithm employed in this research.

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“…Additionally, we have noticed a growing interest in validating some of the proposed theoretical models [6] for the purpose of establishing their validity and/or improving them [14][15][16][17][18][19][20][21][22]. However, despite these above-mentioned efforts, practically all of these models have significant limitations [6]. According to the literature, most were theoretical proposals, only partially validated at best, and have rarely been integrated into routine clinical practice.…”

“…Staging models allow us to integrate clinical information with biomarkers, comorbid conditions, and other significant variables [3]. Thus, they offer a unitary framework for providing effective interventions adapted to the stages of the disorder [4][5][6] and reducing heterogeneity in clinical practice [5,7].…”

Generalisable functional imaging classifiers of schizophrenia have multifunctionality as trait, state, and staging biomarkers

“…These biomarkers have been developed separately in some studies 16,17 , and other studies assumed a shared background 18–20 . In SSD research, few studies have succeeded in developing state markers using neuroimaging, and for staging markers, there is no consensus on biological staging models 21 .…”

Emerging psychopathology and clinical staging in adolescent offspring of parents with bipolar disorder or schizophrenia—A longitudinal study

“…25 They define the progression of illness rather than the diagnosis itself. 22 Studies on the current clinical staging models for SZ or BD focused on the clinical implications of the models, cognitive and neurobiological biomarkers, and on offspring at familial risk [26][27][28][29][30][31][32] but do not use a crossdisorder approach and rarely have a developmental perspective.…”