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Cognitive behavioural therapy for psychosis prevention: a systematic review and meta-analysis

Published online by Cambridge University Press:  22 March 2013

P. Hutton  and
P. J. Taylor
P. Hutton*
Affiliation:
Greater Manchester West Mental Health NHS Foundation Trust, UK University of Manchester, UK
P. J. Taylor
Affiliation:
University of Manchester, UK
*
*Address for correspondence: Dr P. Hutton, Psychosis Research Unit, Psychology Department, Greater Manchester West Mental Health NHS Foundation Trust, Bury New Road, Prestwich, Manchester M25 3BL, UK. (Email: paulhutton@nhs.net)
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Abstract

Background

Clinical equipoise regarding preventative treatments for psychosis has encouraged the development and evaluation of psychosocial treatments, such as cognitive behavioural therapy (CBT).

Method

A systematic review and meta-analysis was conducted, examining the evidence for the effectiveness of CBT-informed treatment for preventing psychosis in people who are not taking antipsychotic medication, when compared to usual or non-specific control treatment. Included studies had to meet basic quality criteria, such as concealed and random allocation to treatment groups.

Results

Our search produced 1940 titles, out of which we found seven completed trials (six published). The relative risk (RR) of developing psychosis was reduced by more than 50% for those receiving CBT at every time point [RR at 6 months 0.47, 95% confidence interval (CI) 0.27–0.82, p = 0.008 (fixed-effects only: six randomized controlled trials (RCTs), n = 800); RR at 12 months 0.45, 95% CI 0.28–0.73, p = 0.001 (six RCTs, n = 800); RR at 18–24 months 0.41, 95% CI 0.23–0.72, p = 0.002 (four RCTs, n = 452)]. Heterogeneity was low in every analysis and the results were largely robust to the risk of an unpublished 12-month study having unfavourable results. CBT was also associated with reduced subthreshold symptoms at 12 months, but not at 6 or 18–24 months. No effects on functioning, symptom-related distress or quality of life were observed. CBT was not associated with increased rates of clinical depression or social anxiety (two studies).

Conclusions

CBT-informed treatment is associated with a reduced risk of transition to psychosis at 6, 12 and 18–24 months, and reduced symptoms at 12 months. Methodological limitations and recommendations for trial reporting are discussed.

Keywords

At-risk mental statecognitive behavioural therapyprodromal psychosissubthreshold symptoms
Type
Review Article
Information
Psychological Medicine , Volume 44 , Issue 3 , February 2014 , pp. 449 - 468
Copyright
Copyright © Cambridge University Press 2013 

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