The Hierarchical Taxonomy of Psychopathology in Clinical High Risk for Psychosis: Validation and Extension

• Published in: Journal of psychopathology and clinical science 2024-04, Vol.133 (3), p.235-244
• Main Authors: Williams, Trevor F., Williams, Alexander L., Cowan, Henry R., Walker, Elaine F., Cannon, Tyrone D., Bearden, Carrie E., Keshavan, Matcheri, Cornblatt, Barbara A., Addington, Jean, Woods, Scott W., Perkins, Diana O., Mathalon, Daniel H., Cadenhead, Kristin S., Stone, William S., Mittal, Vijay A.
• Format: Article
• Language: English
• Subjects: At Risk Populations; Bipolar Disorder; Childhood; Classification; Clinical Models; Clinical outcomes; Comorbidity; Confirmatory factor analysis; Conversion disorder; Female; High risk; Human; Humans; Internalization; Longitudinal Studies; Male; Mental Disorders - diagnosis; Neuroses; Obsessive Compulsive Disorder; Prodromal symptoms; Psychopathology; Psychosis; Psychotic Disorders - diagnosis; Psychotic Disorders - epidemiology; Psychotic symptoms; Self report; Social development; Social functioning; Taxonomies; Taxonomy; Trauma
• ISSN: 2769-7541; 2769-755X; 2769-755X
• DOI: 10.1037/abn0000893

The Hierarchical Taxonomy of Psychopathology (HiTOP) consortium's transdiagnostic dimensional model of psychopathology has considerable support; however, this model has been underresearched in individuals at clinical high risk for psychosis (CHR-P), a population that may advance the model. CHR-P individuals not only have attenuated psychotic symptoms that vary in severity, but also have many comorbid diagnoses and varied clinical outcomes, including disorders with uncertain relations to HiTOP (e.g., obsessive-compulsive disorder). The present study used self-report and interview data from North American Prodrome Longitudinal Study-3 (710 CHR, 96 controls) to replicate the HiTOP model and test specific hypotheses regarding disorders with uncertain relations to its dimensions. Additionally, the present study examined the HiTOP model in relation to childhood trauma, declines in social functioning, and development of full psychosis. Confirmatory factor analysis indicated that the HiTOP model's fit was nearly adequate (e.g., comparative fit index = .89), though several theory-relevant modifications were indicated. Additionally, specific tests were conducted to gain a more fine-grained perspective on how disorders with less clear prior evidence were related to the HiTOP model. Notable findings from these analyses include bipolar spectrum disorders relating to the psychosis super spectrum (i.e., .39 loading), and obsessive-compulsive disorder showing a complex pattern of loadings (e.g., internalizing and psychosis). The final model parsimoniously accounted for childhood trauma (e.g., super spectra rs = .22-.32), associations with current functioning, and predicted future conversion to a psychotic disorder (e.g., super spectra R2 = .13). Overall, these results inform the HiTOP model and suggest its promise for CHR-P research. General Scientific Summary Individuals at risk of developing psychosis often have multiple psychiatric diagnoses; however, existing diagnostic frameworks poorly describe the reality of the symptoms experienced by individuals at risk for psychosis. The present study supported the validity and utility of an alternative framework for describing psychiatric symptoms-the Hierarchical Taxonomy of Psychopathology-by showing its relevance to both psychosis risk factors and clinical outcomes.