Cognitive Predictors of Functioning and Treatment Response in Treatment-Resistant Psychosis: A Transdiagnostic Approach

Patients with primary psychotic disorders who fail to respond adequately to standard antipsychotic treatments are defined as treatment-resistant. While neuropsychological assessment is crucial for evaluating cognitive impairment, its utility in predicting functional and treatment outcomes in individuals with treatment-resistant psychosis (TRP) remains understudied. This study investigates whether neuropsychological functioning predicts functional and treatment outcomes in TRP, utilizing a transdiagnostic approach. Methods An archival retrospective chart review study was conducted on inpatients who received neuropsychological evaluations within the British Columbia Psychosis Program, utilizing neuropsychological, clinical outcome, as well as functional performance and capacity data. Principal component regression was applied to the neuropsychological test battery to determine the association between cognitive factors and functional and treatment outcomes. Results Neuropsychological assessment of the inpatients (N = 206) revealed difficulties in processing speed, working memory, and executive function, and deficits in verbal and nonverbal memory. Principal component analysis identified four cognitive domains: Executive Function/Processing Speed, Crystallized Cognitive Abilities, Visuospatial Ability, and Verbal Memory and Learning. After controlling for symptom severity, Crystallized Cognitive Abilities (B = 0.939, SE = 0.429, p = .030) and Verbal Memory and Learning (B = 0.891, SE = 0.426, p = .038) modestly predicted functional performance, but no associations emerged for functional capacity or treatment outcomes. Conclusions These findings highlight the complex relationship between cognition, daily functioning, and treatment outcomes in TRP. This study stresses the importance of a transdiagnostic approach and advocates further research into mediators of cognition-functioning relationships to improve understanding and interventions for TRP.