Jinyoung Lee

Evaluation of the factor structure of symptoms in patients with schizophrenia

Considering the widespread use of the Positive and Negative Syndrome Scale (PANSS) and its factors around the world in clinical trials, it is clearly necessary to perform a transcultural validation of the factor structure of the PANSS. The purpose of the present study was to examine the PANSS factor structure in a Korean sample of subjects with schizophrenia. A total of 150 outpatients were assessed using the PANSS and other clinical rating scales. Principal component analyses revealed five factors, i.e., negative, cognitive/disorganization, positive, excitement, and depression/anxiety dimensions, which accounted for 64.1% of the total variance. All five factors showed good internal consistency, suggesting that the reliability of the factors extracted was adequate. Significant correlations were found between the five components of the PANSS and the corresponding clinical rating scales. The results of the present study indicate that the five-factor model best fit the data from our patients and that it was validated transculturally. The factor structures should be further validated using various neurobiological methods to ultimately help in clarifying the heterogeneity and pathogenesis of symptomatology in schizophrenia.

Relationship between subjective experiences and psychopathological dimensions in schizophrenia

Objective: Subjective experiences are subtle, self-experienced disturbances, a thorough description of which is provided within the framework of the concept of basic symptoms. Recent studies have shown that subjective experiences have important diagnostic implications for schizophrenia and related disorders. The purpose of the present study was to examine the relationship between subjective experiences and psychopathological dimensions in schizophrenia. Method: Sixty-seven outpatients with schizophrenia were evaluated. Subjective experiences were comprehensively assessed using the Frankfurt Complaint Questionnaire (FCQ). Symptoms of schizophrenia were evaluated using the Manchester Scale (MS). Pearsons partial correlation analysis was performed between the FCQ and the MS scores, controlling for the influence of extrapyramidal adverse effects. Results: The analysis revealed that the MS positive symptom score had significant positive correlations with the FCQ total score and subscales scores. The MS negative symptom score did not have significant correlations with the FCQ scores. Conclusions: The results of our study suggest that subjective experiences are significantly associated with positive symptomatology in schizophrenia, suggesting that they may share a common underlying neural basis. Future prospective studies are necessary to confirm the stability of these relationships and to explore the diagnostic and therapeutic implications of subjective experiences in a diverse group of patients at different stages of illness.

Relationship between cognitive insight and subjective quality of life in outpatients with schizophrenia.

Background The concept of cognitive insight refers to the cognitive processes involved in patients’ re-evaluation of their anomalous experiences and of their misinterpretations. The purpose of the present study was to examine the relationship between cognitive insight and subjective quality of life in patients with schizophrenia to further shed light on the nature of cognitive insight and its functional correlates in schizophrenia. Methods Seventy-one stable outpatients with schizophrenia were evaluated for cognitive insight and subjective quality of life using the Beck Cognitive Insight Scale (BCIS) and the Schizophrenia Quality of Life Scale Revision 4 (SQLS-R4). The symptoms of schizophrenia were also assessed. Pearson’s correlation analysis and partial correlation analysis that controlled for the severity of symptoms were performed to adjust for the possible effects of symptoms. Results The self-reflectiveness subscale score of the BCIS had significant positive correlations with the SQLS-R4 psychosocial domain and total SQLS-R4 scores, indicating that the higher the level of cognitive insight, the lower the subjective quality of life. In partial correlation analysis controlling for symptoms, the BCIS self-reflectiveness subscale score still had a significant correlation with the SQLS-R4 psychosocial domain score. The correlation coefficient between the BCIS self-reflectiveness and total SQLS-R4 scores was reduced to a nonsignificant statistical tendency. Conclusion The results of our study suggest that cognitive insight, particularly the level of self-reflectiveness, is negatively associated with the level of subjective quality of life in outpatients with schizophrenia and that this relationship is not wholly due to the confounding effect of symptoms. Future studies are necessary to explore possible mediating and moderating factors and to evaluate the effects of therapeutic interventions on the relationship.

Relationship between heart rate variability and the severity of psychotic symptoms in schizophrenia

Kim J-H, Ann J-H, Lee J. Relationship between heart rate variability and the severity of psychotic symptoms in schizophrenia. Objective: The relationship between autonomic neurocardiac function and schizophrenia remains elusive. This study investigated the relationship between the heart rate variability (HRV) parameters and the severity of psychotic symptoms in schizophrenic patients. Methods: Twenty-one patients receiving risperidone monotherapy and 21 matched normal control subjects were evaluated for HRV analysis. The severity of schizophrenic symptoms was assessed using the Positive and Negative Syndrome Scale (PANSS) and a five-factor model of the PANSS was used. Results: The value of the ratio of low-to-high frequency spectral power was significantly higher in the patient group. The patient group also showed a significantly lower value of approximate entropy. After controlling the dosage of risperidone, the PANSS total score had significant negative correlations with the standard deviation of all RR intervals (SDNN) and the square root of the mean squared differences of successive normal sinus intervals (RMSSD). With respect to the PANSS factors, the score of the PANSS cognitive/disorganisation factor had significant negative correlations with SDNN and RMSSD. Conclusion: These results provide some evidence that the severity of psychotic symptoms, especially cognitive/disorganisation symptom dimensions, may be associated with reduced HRV, suggesting a potential involvement of neuroautonomic dysfunction in the pathophysiology of specific symptoms of schizophrenia.

Insight change and its relationship to subjective well‐being during acute atypical antipsychotic treatment in schizophrenia

What is known and Objective:  Poor insight is prevalent among patients with schizophrenia and improved insight is one of the major goals of treatment. The purpose of the present study was to examine the relationship between insight and subjective well‐being during acute treatment of schizophrenia with atypical antipsychotics in a naturalistic clinical setting.

Effects of clozapine on heart rate dynamics and their relationship with therapeutic response in treatment-resistant schizophrenia.

Abstract Previous studies have suggested the utility of nonlinear complexity measures of heart rate variability (HRV) in evaluating the regulatory capacity of the neuroautonomic system. The purpose of the present study was to investigate the effects of clozapine on the nonlinear complexity measures of HRV in patients with treatment-resistant schizophrenia to find novel electrophysiological markers that indicate response to clozapine treatment. Forty patients with treatment-resistant schizophrenia were evaluated during 8 weeks of clozapine monotherapy. For nonlinear complexity measures of HRV, the approximate entropy (ApEn) and sample entropy (SampEn) values were obtained. The response rate to clozapine was 37.5%. The results of multivariate analysis of covariance revealed that the ApEn and the SampEn values of HRV at week 8 were significantly higher in the responders than in the nonresponders. Repeated-measures analysis of covariance showed a significant group by time interaction effect in the ApEn and SampEn indices. The responder group showed an increasing pattern of change in these complexity measures after administration of clozapine, whereas the nonresponder group showed a decreasing pattern of change. These results suggest that the nonlinear dynamic complexity measures of HRV, which indicate the irregularity and complexity of the biosystem, may be useful in evaluating the therapeutic changes of neuroautonomic function in schizophrenia. The response to clozapine treatment is expected to be more favorable when the plasticity of the neuroautonomic system reflected in the nonlinear complexity measures is high.

Altered heart rate dynamics associated with antipsychotic-induced subjective restlessness in patients with schizophrenia.

Background Antipsychotic-induced subjective inner restlessness is one of the common and distressing adverse effects associated with antipsychotics; however, its underlying neurobiological basis is not well understood. We examined the relationship between antipsychotic-induced subjective inner restlessness and autonomic neurocardiac function. Methods Twenty-two schizophrenia patients with antipsychotic-induced subjective restlessness, 28 schizophrenia patients without antipsychotic-induced subjective restlessness, and 28 matched healthy control subjects were evaluated. Assessments of the linear and nonlinear complexity measures of heart rate dynamics were performed. Multivariate analysis of variance and correlation analysis were conducted. Results The mean interbeat (RR) interval value was significantly higher in control subjects than in patients with and without antipsychotic-induced subjective restlessness (P < 0.05). The low frequency/high frequency ratio was significantly higher in patients with antipsychotic-induced subjective restlessness than in control subjects and in patients without antipsychotic-induced subjective restlessness (P < 0.05), while the approximate entropy value was significantly lower in patients with antipsychotic-induced subjective restlessness than in control subjects and in patients without antipsychotic-induced subjective restlessness (P < 0.05). Correlation analyses controlling for psychotic symptom severity showed that the degree of antipsychotic-induced restlessness had a significant negative correlation with the value of approximate entropy (P < 0.05). Conclusion The results indicate that antipsychotic-induced subjective restlessness is associated with altered heart rate dynamics parameters, particularly the nonlinear complexity measure, suggesting that it might adversely affect autonomic neurocardiac integrity. Further prospective research is necessary to elucidate the precise interrelationships and causality.

Anomalous subjective experiences in schizophrenia, bipolar disorder, and unipolar depression.

BACKGROUND The purpose of the present study was to compare anomalous subjective experiences in patients with schizophrenia, bipolar disorder, and unipolar depression, in order to elucidate differences in subjective experiences and examine their potential clinical correlates in schizophrenia and mood disorders. METHODS The subjective experiences of 78 outpatients with schizophrenia (n=32), bipolar disorder (n=24) and unipolar depression (n=22), and 32 healthy controls were comprehensively assessed using the Frankfurt Complaint Questionnaire (FCQ). RESULTS The FCQ total score was significantly higher in the schizophrenia and depression groups than in the healthy control group. There were no significant differences in the FCQ total or subscale scores among the schizophrenia, unipolar depression, and bipolar disorder groups. In the schizophrenia group, the Positive and Negative Syndrome Scale negative factor score was a significant negative predictor of the severity of subjective experiences assessed by the FCQ total score. Disruption of subjective experiences in patients with unipolar depression was associated with greater severity of depressive symptoms and younger age. In the bipolar disorder group, women reported more disruptions in subjective experience. CONCLUSIONS Anomalous subjective experiences measured by the FCQ are not specific to schizophrenia, and the severity of these experiences in unipolar depression is substantially high. The finding of a dissimilar pattern of predictors of subjective experiences across different diagnostic groups suggests the complexity and variety of factors contributing to anomalous subjective experiences in schizophrenia and mood disorders.

Preoperative Computed Tomography–Determined Sarcopenia and Postoperative Outcome after Surgery for Non-Small Cell Lung Cancer

Background: Sarcopenia, reduced skeletal muscle mass, is associated with frailty, injuries, and mortality. The purpose of this study was to evaluate the impact of computed tomography–determined sarcopenia on surgical complications and outcomes after resection of non-small cell lung cancer. Methods: For a total 272 non-small cell lung cancer patients that underwent surgery between 2011 and 2016, cross-sectional area of muscle at the third lumbar vertebra (L3) was retrospectively measured using preoperative chest computed tomography images. Sarcopenia was defined as an L3 muscle index of <55 cm2/m2 for men and of <39 cm2/m2 for women. Clinical characteristics, postoperative complications, disease-free survival, and overall survival of patients with or without sarcopenia were compared. Results: A total of 60.3% (n = 164) were male, and mean patient age was 62.9 ± 9.6 years. The prevalence of sarcopenia was 22.4% for all study subjects, 32.9% for men, and 6.5% for women. No significant difference was observed between patients with or without sarcopenia in terms of intensive care unit or hospital stay (p = 0.502 and p = 0.378, respectively), and the presence of sarcopenia was not associated with postoperative complications. Furthermore, no significant difference was observed between the 3-year disease-free survival rate (74.3% vs 66.7%, p = 0.639) or 3-year overall survival rate (83.9% vs 87.7%, p = 0.563) of patients with or without sarcopenia. Conclusion: Sarcopenia as determined by preoperative computed tomography does not appear to have a negative impact on surgical outcome or overall survival for resected non-small cell lung cancer patients.

Subjective experiences in schizophrenia

Recent attention to the early phases of schizophrenia has generated a renewed interest in the subtle, selfexperienced cognitive, perceptual, and emotional changes that have been described since the earliest articulation of dementia praecox [1 – 3]. We agree with Dr Raballo [4] on the intrinsic developmental characteristics of subjective experiences in schizophrenia. According to the original concept, subjective experiences of psychosis occur in several developmental forms: the uncharacteristic basic symptoms, the characteristic and qualitatively peculiar basic symptoms, and the psychotic symptoms per se [2,3]. Following the fi rst psychotic episode, basic symptoms evolve into the post-symptomatic basic stages where some forms of basic symptoms may persist on a level that interferes with functioning [2,3]. Therefore, the structure of the subjective experiences is sensitive to the patients ’ characteristics and their illness stages, and is infl uenced by the instruments used for measurement. As noted in our article and as mentioned by Dr Raballo, the moderate magnitudes of the correlations between subjective experiences and objective psychopathology may be accounted for by this factor. In addition, it is likely that the observed features of patients (i.e. third-person data), and the patients ’ subjective experiences (i.e. fi rstperson data), gravitate into separate dimensions, without implying a real split between them or a homogeneity of subjective experience [5]. In assessing basic symptoms or subtle changes in the structure of subjective experiences, it is preferable to use the Bonn Scale for the Assessment of Basic Symptoms (BSABS), which is a comprehensive interview schedule that has been translated into several languages, since self-rating questionnaires, with the possible exception of the Frankfurt Complaint Questionnaire, do not necessarily target the qualitative or structural alterations of subjective experiences [5]. Nonetheless, the usefulness of the BSABS as a screening measure for the early detection of schizophrenia should be evaluated in studies using general population with a large sample size to allow for naturalistic sampling [6]. Subjective experience is not an observable one. However, such experience is considered to be a fundamental feature of schizophrenia-spectrum disorders [7,8] and thus may represent a potentially important trait phenotype although disturbances of subjective experiences are poorly considered in the current diagnostic system. The issue of fi ne-grained clinical assessment is always at the forefront of the modellization of the vulnerability to schizophrenia.