Cognitive Enhancement Therapy Improves Quality of Life Among Individuals with Schizophrenia Who Misuse Alcohol and Cannabis

Background and Purpose: Individuals with schizophrenia, a severe and persistent mental illness, are burdened with a poor quality of life (QoL). Cognitive remediation interventions, such as Cognitive Enhancement Therapy (CET), have been shown to be an effective treatment for schizophrenia, but the direct impact on QoL is unknown. QoL is an important intervention outcome in social work research and practice, and this study sought to examine the effect of CET on QoL in individuals with schizophrenia who also misuse alcohol and/or cannabis.

Methods: A small sample of substance misusing outpatients with schizophrenia were randomized to either CET (n = 22) or usual care (n= 9) for 18-months of treatment in a feasibility trial of CET for individuals misusing substances (Eack et al., 2015). Participants completed the World Health Organization Quality of Life Measure-Abbreviated Version (WHOQOL-BREF) prior to starting treatment and at 6-, 9-, 12-, and 18-month time points. The WHOQOL-BREF produces four domains scores of QoL: physical health, psychological, social relationships, and environment. Intent-to-treat linear growth curve models were used to examine differential longitudinal changes in QoL between CET and usual care, adjusting for baseline age, sex, race, and baseline drug use severity.

Results: The results indicated that participants in CET improved significantly more on the social relationships domain of QoL over the 18 months of treatment compared to participants in usual care [d = .617, t(46) = -2.275, p = .0276]. It was observed that participants in usual care had a linear decrease in their social relationships QoL compared to the participants in CET who had a linear increase. A trend-level treatment effect was also observed for the environment domain of QoL, such that participants in CET had improved more than participants in usual care with regard to safety, leisure activities, transportation, access to health services, and monetary resources to cover their needs [d = .807, t(46) = -1.886, p = .0656].  

Conclusion and Implications: CET may improve QoL, especially with regard to social relationships, in people living with schizophrenia and comorbid addiction issues. Given that social functioning is a domain considerably impacted by schizophrenia, the results highlight the utility of social workers providing cognitive remediation treatments to clients with schizophrenia. The findings also provide further evidence that CET is a feasible and possibly effective treatment for the portion of the population with schizophrenia that also misuses alcohol and/or cannabis.  

References

Eack, S. M., Hogarty, S. S., Greenwald, D. P., Litschge, M. Y., McKnight, S. A., Bangalore, S.S., ... & Cornelius, J. R. (2015). Cognitive Enhancement Therapy in substance misusing schizophrenia: Results of an 18-month feasibility trial. Schizophrenia Research, 161(2), 478-483.