Differences in Executive Function Among Patients With Schizophrenia, Their Unaffected First-Degree Relatives, and Healthy Participants

Abstract

Background Patients with schizophrenia (SCZ) display impaired executive functions compared with healthy controls (HCs). Furthermore, unaffected first-degree relatives (FRs) of patients with SCZ independently perform worse executive functions than do HCs. However, few studies have investigated the differences in executive functions assessed among patients with SCZ, FRs, and HCs, and the findings are inconsistent. Methods We investigated diagnostic differences in executive functions, namely, (i) numbers of categories achieved (CA), (ii) total errors (TE) and (iii) %perseverative errors of Nelson types (%PEN), using the Wisconsin card sorting test (WCST) among patients with SCZ (n=116), unaffected FRs (n=62) and HCs (n=146) at a single institute. Correlations between these executive functions and clinical variables were investigated. Results Significant differences existed in all executive functions among diagnostic groups (CA, F2,319=15.5, p=3.71×10-7; TE, F2,319=16.2, p=2.06×10-7; and %PEN, F2,319=21.3, p=2.15×10-9). Patients with SCZ had fewer CA and more TE and %PEN than those of HCs (CA, Cohen’s d=-0.70, p=5.49×10-8; TE, d=0.70, p=5.62×10-8; and %PEN, d=0.82, p=2.85×10-10) and FRs (TE, d=0.46, p=3.73×10-3 and %PEN, d=0.38, p=0.017). Of the three executive functions, CA and %PEN of FRs were intermediately impaired between patients with SCZ and HCs (CA, d=-0.41, p=0.011 and %PEN, d=0.41, p=0.012). In contrast, no significant difference in TE existed between FRs and HCs (d=0.22, p=0.18). Although CA and TE were affected by the duration of illness (p<0.017), %PEN was not affected by any clinical variable in patients with SCZ (p>0.017). Conclusions Executive function, particularly %PEN, could be a useful intermediate phenotype for understanding the genetic mechanisms implicated in SCZ pathophysiology.

Efficacy of acupuncture on cognitive function in poststroke depression: study protocol for a randomized, placebo-controlled trial

“…The secondary outcomes include the Wisconsin Card Sorting Test (WCST) and the latency and amplitude of the ERP components P1, N170, and P3 at week 4. The WCST [ 24 ] is being adopted to assess cognitive function. Participants are required to match response cards to the four stimulus cards along one of the three dimensions (color, form, or number) by pressing one of the 1 to 4 number keys on the computer keyboard.…”

“…The WCST [ 24 ] is being adopted to assess cognitive function. Participants are required to match response cards to the four stimulus cards along one of the three dimensions (color, form, or number) by pressing one of the 1 to 4 number keys on the computer keyboard.…”

Efficacy of Acupuncture On Cognitive Function In Poststroke Depression: Study Protocol For A Randomized, Placebo-Controlled Trial

“…The WCST [22] is being adopted to assess cognitive function. Participants are required to match response cards to the four stimulus cards along one of the three dimensions (color, form, or number) by pressing one of the 1 to 4 number keys on the computer keyboard.…”

Polygenic Risk Scores Differentiating Schizophrenia From Bipolar Disorder Are Associated With Premorbid Intelligence in Schizophrenia Patients and Healthy Subjects

“…Cognitive impairments, including impaired intelligence, are a core feature of SCZ and BD ( Schaefer et al, 2013 ; Trotta et al, 2015 ; Solé et al, 2016 ; Ohi et al, 2019 ). In addition, cognitive impairments are, to a lesser degree, found in unaffected first-degree relatives of SCZ and BD patients ( Glahn et al, 2010 ; Ohi et al, 2019 ; de Zwarte et al, 2020 ; Kataoka et al, 2020 ). Cognitive impairments are relatively independent of psychotic (positive and negative) and manic symptoms, and cognitive impairments result in poor functional outcomes, such as social and occupational dysfunction ( Green et al, 2000 ; Jaeger et al, 2007 ; Kahn and Keefe 2013 ).…”