Associations between daily living skills, cognition, and real-world functioning across stages of schizophrenia; a study with the Schizophrenia Cognition Rating Scale Japanese version

Yuko Higuchi; Tomiki Sumiyoshi; Tomonori Seo; Motomu Suga; Tsutomu Takahashi; Shimako Nishiyama; Yuko Komori; Kiyoto Kasai; Michio Suzuki

doi:10.1016/j.scog.2017.01.001

Associations between daily living skills, cognition, and real-world functioning across stages of schizophrenia; a study with the Schizophrenia Cognition Rating Scale Japanese version

Schizophr Res Cogn. 2017 Feb 22:7:13-18. doi: 10.1016/j.scog.2017.01.001. eCollection 2017 Mar.

Authors

Yuko Higuchi¹, Tomiki Sumiyoshi², Tomonori Seo¹, Motomu Suga^{3

4}, Tsutomu Takahashi¹, Shimako Nishiyama¹, Yuko Komori¹, Kiyoto Kasai³, Michio Suzuki¹

Affiliations

¹ Department of Neuropsychiatry, University of Toyama Graduate School of Medicine and Pharmaceutical Sciences, 2630 Sugitani, Toyama 930-0194, Japan.
² Department of Clinical Epidemiology, Translational Medical Center, National Center of Neurology and Psychiatry, Japan.
³ Department of Neuropsychiatry, Graduate School of Medicine, The University of Tokyo, Japan.
⁴ Department of Rehabilitation, The University of Tokyo Hospital, Japan.

Abstract

Cognitive function is impaired in patients with schizophrenia-spectrum disorders, even in their prodromal stages. Specifically, the assessment of cognitive abilities related to daily-living functioning, or functional capacity, is important to predict long-term outcome. In this study, we sought to determine the validity of the Schizophrenia Cognition Rating Scale (SCoRS) Japanese version, an interview-based measure of cognition relevant to functional capacity (i.e. co-primary measure). For this purpose, we examined the relationship of SCoRS scores with performance on the Brief Assessment of Cognition in Schizophrenia (BACS) Japanese version, a standard neuropsychological test battery, and the Social and Occupational Functioning Assessment Scale (SOFAS), an interview-based social function scale. Subjects for this study (n = 294) included 38 patients with first episode schizophrenia (FES), 135 with chronic schizophrenia (CS), 102 with at-risk mental state (ARMS) and 19 with other psychiatric disorders with psychosis. SCoRS scores showed a significant relationship with SOFAS scores for the entire subjects. Also, performance on the BACS was significantly correlated with SCoRS scores. These associations were also noted within each diagnosis (FES, CS, ARMS). These results indicate the utility of SCoRS as a measure of functional capacity that is associated both with cognitive function and real-world functional outcome in subjects with schizophrenia-spectrum disorders.

Keywords: ARMS, at risk mental state; At risk mental state; BACS; BACS, Brief Assessment of Cognition in Schizophrenia; CAARMS, Comprehensive Assessment of at risk mental state; Co-primary measure; Cognition; JART, Japanese Adult Reading Test; PANSS, Positive and Negative Syndrome Scale; SCoRS; SCoRS, Schizophrenia Cognition Rating Scale; SOFAS; SOFAS, Social and Occupational Functioning Assessment Scale; Schizophrenia.