Identification of clinically meaningful relationships among cognition, functionality, and symptoms in subjects with schizophrenia or schizoaffective disorder
ABSTRACT INTRODUCTION: Cognitive impairment in schizophrenia and schizoaffective disorder is a major determinant of disability. This study explored the relationships among cognitive functioning, clinical symptoms, overall functionality, and demographic characteristics. METHODS: This was a post hoc analysis of a 52-week, prospective, randomized, double-blind study (N=323) comparing 2 doses of risperidone long-acting injectable (RLAI) in stable subjects with schizophrenia or schizoaffective disorder. Cognitive evaluations were performed and standardized using a healthy age- and sex-matched comparison group. Simple and multiple regression models were used to identify relationships among neurocognitive composite scores (NCS), clinical symptom end points (Positive and Negative Syndrome Scale [PANSS] total and factor scores), overall functionality (Personal and Social Performance [PSP] score), and demographics. RESULTS: A simple regression model identified significant relationships between the NCS at end point and PANSS total score, PANSS disorganized thoughts factor score, functioning (PSP) and age. A 1-point decrease on PANSS total score and PANSS disorganized thoughts factor score corresponded to an increase in NCS of 0.126-point, and 0.81-point increases, respectively. A 1-point increase on the PSP corresponded to a 0.186-point increase in the NCS T-score. Among the demographic variables, only age correlated significantly with cognition (10-year increase in age corresponded to 1.1-point decrease in NCS T-score) in a multiple regression model. CONCLUSION: Improved cognition was associated with beneficial changes in functional status and clinical symptoms (particularly disorganization symptoms) in subjects with schizophrenia/schizoaffective disorder. Older subjects showed less overall cognitive improvement. Improved cognitive and functional outcome is correlated with symptom improvements in RLAI-treated patients with schizophrenia.
SourceAvailable from: Jooyoung Oh[Show abstract] [Hide abstract]
ABSTRACT: Effective integration of visual information is necessary to utilize abstract thinking, but patients with schizophrenia have slow eye movement and usually explore limited visual information. This study examines the relationship between abstract thinking ability and the pattern of eye gaze in patients with schizophrenia using a novel theme identification task. Twenty patients with schizophrenia and 22 healthy controls completed the theme identification task, in which subjects selected which word, out of a set of provided words, best described the theme of a picture. Eye gaze while performing the task was recorded by the eye tracker. Patients exhibited a significantly lower correct rate for theme identification and lesser fixation and saccade counts than controls. The correct rate was significantly correlated with the fixation count in patients, but not in controls. Patients with schizophrenia showed impaired abstract thinking and decreased quality of gaze, which were positively associated with each other. Theme identification and eye gaze appear to be useful as tools for the objective measurement of abstract thinking in patients with schizophrenia.Behavioral and Brain Functions 04/2014; 10(1):13. DOI:10.1186/1744-9081-10-13 · 2.00 Impact Factor
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ABSTRACT: Objective To evaluate the efficacy of lurasidone for schizophrenia using an established five-factor model of the Positive and Negative Syndrome Scale (PANSS). Methods Patient-level data were pooled from five randomized, double-blind, placebo-controlled, 6-week studies of lurasidone (fixed doses, 40–160 mg/d) for patients with an acute exacerbation of schizophrenia. Changes in five established PANSS factors were assessed using mixed-model repeated measures analysis. Results Compared with placebo (n = 496), lurasidone (n = 1029, dose groups pooled) significantly improved the PANSS total score at Week 6 (−22.6 vs. −12.8; P < 0.001; effect size, 0.45), as well as all factor scores (P < 0.001 for each): positive symptoms (−8.4 vs. −6.0; effect size, 0.43), negative symptoms (−5.2 vs. −3.3; effect size, 0.33), disorganized thought (−4.9 vs. −2.8; effect size, 0.42), hostility/excitement (−2.7 vs. −1.6; effect size, 0.31), and depression/anxiety (−3.2 vs. −2.3; effect size, 0.31). Separation from placebo occurred at Week 1 for the positive symptoms, disorganized thought, and hostility/excitement factors and at Week 2 for the other factors. Conclusions In this pooled analysis of short-term studies in patients with acute schizophrenia, lurasidone demonstrated significant improvement for each of the five PANSS factor scores, indicating effectiveness across the spectrum of schizophrenia symptoms.European Psychiatry 09/2014; 30(1). DOI:10.1016/j.eurpsy.2014.08.001 · 3.21 Impact Factor
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ABSTRACT: Objective The purpose of this study was to examine the relative contributions of disorganization and cognitive dysfunction to quality of life (QOL) in patients with stable schizophrenia. Methods A total of 276 consecutive outpatients with stable schizophrenia were enrolled in a cross-sectional study. We performed a mediation analysis to assess the specific effect of disorganization on QOL, as assessed by the Heinrichs–Carpenter Quality of Life Scale (QLS), and the possible mediating role of cognitive dysfunction. Results Our findings were as follows: (i) disorganization was negatively related to the total QLS score; (ii) disorganization was negatively related to two of the four QLS domains, namely the role-functioning domain (occupational/educational) and the intrapsychic functioning domain (e.g., motivation, curiosity, and empathy); and (iii) verbal memory was a partial mediator of the relationship between disorganization and QLS (the total score and the two above-mentioned domains). Conclusions Disorganization demonstrated direct and indirect effects via verbal memory on two domains of functioning, as measured by the QLS. These results highlight the importance of improving disorganization and cognition (particularly verbal memory) to improve the functional outcomes of patients with schizophrenia.Schizophrenia Research 03/2014; 153(1-3). DOI:10.1016/j.schres.2014.01.013 · 4.43 Impact Factor