Cognitive enhancement therapy for early-course schizophrenia: effects of a two-year randomized controlled trial

Abstract

Objective: The early application of cognitive rehabilitation may afford long-term functional benefits to patients with schizophrenia. This study examined the two-year effects of an integrated neurocognitive and social-cognitive rehabilitation program, cognitive enhancement therapy (CET), on cognitive and functional outcomes in early-course schizophrenia.

Methods: Early-course outpatients (mean+/-SD illness duration=3.19+/-2.24 years) with schizophrenia or schizoaffective disorder were randomly assigned to CET (N=31) or enriched supportive therapy (EST) (N=27), an illness management intervention utilizing psychoeducation and applied coping strategies, and treated for two years. Multivariate composite indexes of cognitive, social adjustment, and symptom domains were derived from assessment batteries administered annually by computer-based tests and raters not blind to treatment assignment.

Results: Of the 58 participants who were randomly assigned and treated, 49 and 46 completed one year and two years of treatment, respectively. Intent-to-treat analyses showed significant differential effects favoring CET on social cognition, cognitive style, social adjustment, and symptomatology composites during the first year of treatment. After two years, moderate effects (d=.46) were observed favoring CET for enhancing neurocognitive function. Strong differential effects (d>1.00) on social cognition, cognitive style, and social adjustment composites remained at year 2 and also extended to measures of symptomatology, particularly negative symptoms.

Conclusions: CET appears to be an effective approach to the remediation of cognitive deficits in early schizophrenia that may help reduce disability in this population. The remediation of such deficits should be an integral component of early intervention programs treating psychiatrically stable schizophrenia outpatients.

Figure 1

Participant Flow Over the Course of Two Years of a Randomized Trial of Cognitive Enhancement Therapy.

Figure 2

Differential Improvement of Persons Receiving Cognitive Enhancement Therapy Versus Enriched Supportive Therapy on Composite Indexes of Cognition and Behavior.