Cognitive-Behavioral Social Skills Training for patients with late-life schizophrenia and the moderating effect of executive dysfunction

The objectives of this study are to test the efficacy of Cognitive-Behavioral Social Skills Training (CBSST) in enhancing social function in a sample of older patients with schizophrenia, and to assess whether baseline cognition moderates response to CBSST. To address these objectives, we conducted a randomized controlled trial of 63 participants, randomized 1:1 into CBSST or Treatment-As-Usual (TAU). The setting was a community-based geriatric mental health outpatient clinic in Toronto, Ontario, Canada. Data were collected at baseline, and week 18, 36 and 52, between June 2008 and May 2014. Participants were outpatients, aged 60 or older, with a diagnosis of schizophrenia or schizoaffective disorder and no evidence of dementia or other conditions associated with cognitive or functional impairment. The intervention was a weekly group CBSST for 36 weeks. Cognition, including executive function, was assessed at baseline. Modified total score on the Independent Living Skills Survey (ILSS) at 18, 36, and 52 weeks was the primary outcome measure. In a linear mixed model analysis, the ILSS trajectory was better in the CBSST group than the TAU group, with significantly better function at 36 (Cohen's d = 0.75) and 52 weeks (Cohen's d = 0.92). Baseline executive dysfunction moderated CBSST response, whereby participants with more severe executive dysfunction experienced the most improvement in ILSS. CBSST was efficacious in patients with late-life schizophrenia and prevented decline in social function over a one-year period. CBSST was most beneficial for patients with more severe executive dysfunction, i.e., those who needed skills training the most.