Mechanisms and Durability of Meaningful Functional Improvement in Cognitive Enhancement Therapy for Early Course Schizophrenia

Background and Purpose: Schizophrenia is a chronic and disabling disorder that is frequently characterized by marked impairments in cognition. These impairments are known to be present at the onset of the disorder and significantly predictive of long-term difficulties in functioning and behavior. Psychosocial cognition rehabilitation approaches have emerged as effective strategies at remediating cognitive impairments early in the course of schizophrenia, yet the degree to which improvements in cognition translate into meaningful and lasting improvements in functional outcome early in the disorder remains unclear. This study aimed to elucidate the cognitive mechanisms and durability of functional improvement previously observed in a two-year trial of Cognitive Enhancement Therapy (CET; www.CognitiveEnhancementTherapy.com), a comprehensive cognitive rehabilitation program, in individuals with early course schizophrenia.

Methods: Outpatients in the early course of schizophrenia or schizoaffective disorder were randomly assigned and treated in a two-year trial with CET (n = 31) or an active Enriched Supportive Therapy (EST) control (n = 27). A comprehensive battery of measures of cognitive and functional outcome were administered annually during the two years of active treatment. Functional assessments were then re-administered at 1-year post-treatment to assess the durability of functional gains. Linear mixed-effects models were used to estimate differential rates of change in functional outcomes between individuals receiving CET and EST at treatment completion and 1-year follow-up. Individual growth curve models were then used to examine the mediating impact of cognitive improvement during CET on functional change.

Results: Over the course of two years of treatment, individuals receiving CET demonstrated large (d = 1.54) differential improvements in social adjustment that extended to meaningful domains of functional outcome including employment, social functioning, and major role adjustment. At 1-year post-treatment follow-up, individuals treated with CET continued to maintain a highly significant (p = .003) advantage in functional outcome compare to those treated with EST. Results from a series of individual growth curve models revealed that functional improvement during the course of CET was significantly mediated by improvements in both neurocognition (p = .047) and social cognition (p = .039). When examining the relative impact of neurocognitive and social-cognitive change on functional outcome, improved social cognition exhibited the strongest relationship with functional improvement.

Conclusions and Implications: Cognitive rehabilitation can result in meaningful and lasting improvements for individuals in the early course of schizophrenia. Improved social and non-social cognitive processes are active mechanisms of functional change and critical ingredients in reducing disability in this population. As the primary providers of psychosocial treatments for individuals with schizophrenia, social work practitioners should consider the use of cognitive rehabilitation approaches, such as CET, as an effective adjunct to routine pharmacotherapy.