J Korean Neuropsychiatr Assoc.  2018 Aug;57(3):210-224. 10.4306/jknpa.2018.57.3.210.

Ultra-High Risk for Psychosis : Clinical Characteristics and Diagnosis

• An SK

• KMID: 2429225
• DOI: http://doi.org/10.4306/jknpa.2018.57.3.210

Abstract

Early detection is a crucial milestone in the prevention and treatment of schizophrenia spectrum psychosis, which might alter the course of schizophrenia. Currently, there are two complementary approaches to characterizing the clinical-high risk state of psychosis : the ultra-high risk (UHR) and basic symptoms criteria. Individuals at UHR have two phase-specific problems : heightened risk for the potential pathology of schizophrenia spectrum psychosis and the symptoms, distress and psychosocial functional impairment, which make them seek help. The clinical characteristics of UHR are similar to those of overt psychotic disorders in terms of psychopathological symptoms dimensions, psychosocial disability, neurocognitive and socio-cognitive impairments, history of trauma and abuse experience, lack of protective factors and dysfunctional metacognitive beliefs, and the comorbidity of psychiatric illness. Regarding the risk, the pretest risk probability of a psychotic disorder in each high-risk clinic is considered an important factor for predicting the power of an early detection strategy. For the distress and psychosocial disability, the strategies of the therapeutic intervention will be a focus of clinical attention. On the follow-up, one of third of the UHR individuals have sufficient positive symptom to fulfil the at-risk criteria. Most of the UHR individuals have suffered from comorbid psychiatric illness at the times of both baseline and follow-up, and there is no improvement of psychosocial functioning. Currently, it is essential to optimize the early detection and intervention strategy according to the referring and recruitment characteristics of each high-risk clinic in Korean practice situations.

Keyword

Schizophrenia; Ultra-high risk for psychosis; Basic symptom; Prodrome

MeSH Terms

Comorbidity
Diagnosis*
Follow-Up Studies
Pathology
Protective Factors
Psychotic Disorders*
Schizophrenia

Figure

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  Fig. 1 Conceptual terms of early detection strategies in schizophrenia spectrum psychosis.

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  Fig. 2 Model of the hypothetical relationship and interactions of the schizotypy, BS, APSS, and overt FEP (according to Klosterkötter21) and Debbané et al.22)). BS : Basic symptom, APSS : Attenuated positive symptom syndrome, FEP : First-episode schizophrenia spectrum psychosis.

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  Fig. 3 Hypothetical early course of the schizophrenia spectrum psychosis (according to Schultze-Lutter and Schimmelmann23)).

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  Fig. 4 Hazard plots for basic symptoms based on the levels of physical anhedonia in individuals (n=77) at the ultra-high risk for psychosis at the Clinic FORYOU of the GRAPE project (according to Bang et al.34)).

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  Fig. 5 Kaplan-Meier curve for the transition to schizophrenia spectrum psychosis in individuals (n=77) at the ultra-high risk for psychosis at the Clinic FORYOU of the Green Program of Recognition and Prevention of Early Psychosis project (Bang et al.34)).

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