Cognitive Enhancement Therapy in substance misusing schizophrenia: Results of an 18-month feasibility trial

Abstract

Substance use is a frequent problem in schizophrenia, and although many substance misusing patients with the disorder also experience considerable cognitive impairments, such individuals have been routinely excluded from clinical trials of cognitive remediation that could support their functional and addiction recovery. This study conducted a small-scale feasibility trial of Cognitive Enhancement Therapy (CET) in substance misusing schizophrenia patients to assess the feasibility and efficacy of implementing comprehensive neurocognitive and social-cognitive remediation in this population. A total of 31 schizophrenia outpatients meeting addiction severity criteria for alcohol and/or cannabis use were randomized to 18 months of CET or usual care. Feasibility findings indicated high degrees of satisfaction with CET, but also presented significant challenges in the recruitment and retention of substance misusing patients, with high levels of attrition (50%) over the study period, primarily due to positive symptom exacerbation. Intent-to-treat efficacy analyses showed large and significant improvements in neurocognition (d = .86), social cognition (d = 1.13), and social adjustment (d = .92) favoring CET. Further, individuals treated with CET were more likely to reduce alcohol use (67% vs. 25%) during treatment (p = .021). These results suggest that once engaged and stabilized, CET is a feasible and potentially effective treatment for cognitive impairments in patients with schizophrenia who misuse alcohol and/or cannabis. Substance misusing patients who are able to engage in treatment may be able to benefit from cognitive remediation, and the treatment of cognitive impairments may help improve substance use outcomes among this underserved population.

Patterns of Substance Use During Cognitive Enhancement Therapy: An 18-Month Randomized Feasibility Study

“…Cognitive improvements in processing speed, visual learning, and problem-solving were all related to reduced likelihood of alcohol and/or cannabis use over the course of the 18-month trial. When combined with previously reported evidence on the large benefits of cognitive enhancement therapy to cognition and functional outcome in this sample (Eack et al, 2015), these preliminary findings suggest that cognitive remediation may be beneficial for supporting some aspects of addictive behavior change in schizophrenia and point to the specific cognitive domains of processing speed, visual learning, and problem-solving as relevant therapeutic targets for patients misusing substances.…”

“…Of the 22 patients randomized to cognitive enhancement therapy, 10 completed the full 18-months of treatment (4 withdrew consent, 4 experienced significant symptom instability, 2 were later found to be ineligible, 1 failed to engage in treatment, and 1 was incarcerated); and of the 9 assigned to usual care, 8 completed the 18-month assessment protocol (1 withdrew consent); χ 2 (1, N = 31) = 3.33, p = .068. A detailed description of participant flow throughout the study, including a discussion of attrition, has been provided elsewhere (Eack et al, 2015). All participants provided written informed consent prior to study participation, and the study was approved and reviewed annually by the University of Pittsburgh Institutional Review Board.…”

“…A description of the trial methods and CONSORT diagram has been previously reported elsewhere (Eack et al, 2015) and this is a secondary analysis of substance use trajectories from the parent trial. Inclusion criteria consisted of (1) age 18-60 years, (2) diagnosis of schizophrenia or schizoaffective disorder according to the Structured Clinical Interview for DSM-IV (SCID; First, Spitzer, Gibbon, & Williams, 2002), (3) moderate or higher (≥ 4) addiction severity for cannabis or alcohol on the Addiction Severity Index (McLellan, Luborsky, Woody, O'Brien, 1980), (4) symptom stabilization (no significant exacerbations within the past month) on antipsychotic medications evaluated using the SCID and medical record review, (5) IQ ≥ 80, (6) fluency in English, and (7) significant cognitive and social disability on the Cognitive Styles and Social Cognition Eligibility Interview (Hogarty et al, 2004).…”

“…Unfortunately, with few exceptions (e.g., McGurk, Mueser, Feldman, Wolfe, & Pascaris, 2007), people with comorbid substance use problems have been largely excluded from trials of cognitive remediation, bringing little evidence to bear on the potential benefits of these approaches to addiction problems in this population. Recently, we conducted an initial feasibility randomized trial of cognitive enhancement therapy (Hogarty & Greenwald, 2006) for outpatients with schizophrenia who were misusing alcohol and/or cannabis, and found significant and large improvements on neurocognition ( d = .93), social cognition ( d = .62), and functional outcome ( d = 1.15) compared to usual care (Eack et al, 2015). We also observed preliminary evidence that those receiving cognitive enhancement therapy may have been more likely to reduce the number of days they used alcohol than those receiving usual care.…”

“…This research follows up on these promising results by conducting a secondary analysis of substance use trajectories from our previous clinical trial (Eack et al, 2015) using individual growth curve modeling of daily alcohol and cannabis use among the intent-to-treat sample of enrolled patients. Based on our preliminary results, we hypothesized that cognitive enhancement therapy would significantly reduce the likelihood of alcohol and cannabis use over the course of treatment compared to usual care.…”