A systematic review of factors that influence the efficacy of cognitive remediation therapy in schizophrenia

Abstract

Objective: Cognitive remediation therapy is a moderately effective intervention for ameliorating cognitive deficits in individuals with schizophrenia-related disorders. With reports of considerable variability in individual response to cognitive remediation therapy, we need to better understand factors that influence cognitive remediation therapy efficacy to realise its potential. A systematic review was conducted to identify and evaluate predictors of cognitive outcome. Methods: An electronic database search was conducted identifying peer-reviewed articles examining predictors of cognitive response to cognitive remediation therapy. Results: A total of 40 articles accounting for 1681 cognitive remediation therapy participants were included; 81 distinct predictors of cognitive response were identified. Data synthesis and discussion focused on 20 predictors examined a minimum three times in different studies. Few of the examined predictors of cognitive outcome following cognitive remediation therapy were significant when examined through systematic review. A strong trend was found for baseline cognition, with reasoning and problem solving and working memory being strongly predictive of within-domain improvement. Training task progress was the most notable cross-domain predictor of cognitive outcome. Conclusion: It remains unclear why a large proportion of participants fail to realise cognitive benefit from cognitive remediation therapy. However, when considering only those variables where a majority of articles reported a statistically significant association with cognitive response to cognitive remediation therapy, three stand out: premorbid IQ, baseline cognition and training task progress. Each of these relates in some way to an individual’s capacity or potential for change. There is a need to consolidate investigation of potential predictors of response to cognitive remediation therapy, strengthening the evidence base through replication and collaboration.

Predictors of Long-Term Improvement Following Cognitive Remediation in a Sample With Elevated Depressive Symptoms

“…Cognitive performance at baseline did not predict outcomes for attention or EF in our sample. This finding is contrary to a selection of findings regarding schizophrenia (Reser et al, 2019) but in accordance with MDD research (Listunova et al, 2020). One notable exception was that higher IQ estimates were associated with improvement in everyday EF at the trend level.…”

“…Excluding participants above the age of 60 years restricted the age range and reduced the sample variability of the present study, potentially limiting the prospect of obtaining significant results. Nonetheless, the overall available evidence does not indicate that age is a reliable predictor of CR outcomes (Reser et al, 2019;Listunova et al, 2020;Seccomandi et al, 2020). However, in accordance with previous research on MDD (Motter et al, 2016;Listunova et al, 2020), neither gender nor receiving concurrent treatments predicted improvements in cognition or everyday EF, with the latter indicating no additive effect on cognition of combining CR with antidepressant medication.…”

“…Moreover, no consistent barriers to improvement have been identified to date, so these findings suggest that MDD patients have the potential to improve following CR, regardless of their baseline characteristics. For advances in the field, large-scale and fine-grained investigations with a priori hypotheses are required (Reser et al, 2019;Seccomandi et al, 2020). In addition, as has been suggested for schizophrenia, we may need to go beyond generic demographic and clinical factors to predict CR outcomes reliably (Reser et al, 2019).…”

“…Interestingly, CR findings diverge from psychotherapy research in MDD, where illness characteristics such as greater depression symptom severity, younger age at onset, and more previous episodes have all been associated with poorer responses in relation to depressive symptom alleviation ( Hamilton and Dobson, 2002 ). Moreover, in schizophrenia research, where predictors and moderators of CR effectiveness have been more frequently studied, most of the factors reviewed fail to significantly influence CR treatment response ( Reser et al, 2019 ; Seccomandi et al, 2020 ). However, in a selection of studies, better baseline performance in several cognitive domains predicted both cognitive and functional improvement, while increased chronicity and severity of schizophrenia has been associated with worse CR outcomes ( Medalia and Richardson, 2005 ; Kurtz et al, 2009 ; Vita et al, 2013 ; Lindenmayer et al, 2017 ).…”

Free Thyroxine Concentrations Moderate the Response to a Cognitive Remediation Therapy in People With Early Psychosis: A Pilot Randomized Clinical Trial

“…Although CRT is an effective approach, there are data showing that 25–44% of the participants receiving this intervention will not improve ( 5 , 16 , 17 ). To date, only a limited number of studies have considered how individual characteristics may affect treatment response.…”