Changing Seasonal Pattern of Suicides in Korea Between 2000 and 2019

Objective@#This study aimed to investigate the changing seasonal pattern of suicides in Korea between 2000 and 2019. @*Methods@#We calculated a seasonal pattern of suicides between 2000 and 2019 using a non-stationary cosinor model. In addition, we estimated the effect of each month on the suicide incidence compared to a reference month, using a generalized linear model with a categorical variable of the month. Then, we visualized the rate ratio curves of suicides by gender, age group, and subperiod. @*Results@#We observed a seasonal pattern of suicides in Korea with a spring peak and a winter trough. The seasonal ups and downs were most pronounced in suicides among the elderly ≥65 years. However, the seasonal pattern has not been consistent over the past two decades, with lowering seasonal peaks since 2012. The amplitude of seasonality was also lower in 2010–2019 than in 2000–2009. @*Conclusion@#The seasonal pattern of suicides seems to have diminished in Korea in recent years. Thus, we need further studies to investigate climatic and non-climatic factors influencing the seasonality of suicides and the consequence of the change.

Decline in Hospital Visits by Patients with Schizophrenia Early in the COVID-19 Outbreak in Korea

Objective@#This study investigated trends in hospital utilization by patients with schizophrenia during the first wave of the COVID-19 outbreak in Korea. @*Methods@#The Prophet algorithm was used to predict the monthly number of patients with schizophrenia in 2020 based on medical insurance data between 2010 and 2019. The projected expectations were compared with the actual number of patients receiving outpatient and inpatient treatment each month in the first half of 2020. We conduct interrupted time series analyses of short-term data to determine the significance of recent changes in the trend of hospital visits by patients with schizophrenia. @*Results@#The prediction model showed that the actual number of patients receiving treatment each month during the early COVID-19 outbreak decreased by up to 3.6% compared to the projected expectations. The interrupted time series model also revealed a significant change in hospital utilization compared to the year before the onset of COVID-19 in Korea (F = 8.961, p = 0.010). @*Conclusion@#This suggests that many patients with schizophrenia were not receiving adequate treatment during the COVID-19 outbreak. A strategy should be developed to keep treating patients with schizophrenia during the COVID-19 pandemic.

Current and Future Trends in Hospital Utilization of Patients With Schizophrenia in Korea: A Time Series Analysis Using National Health Insurance Data

Objective@#This study aimed to investigate trends in hospital utilization of patients with schizophrenia during the last 10 years in Korea and to predict future trends using time series analysis. @*Methods@#We determined the numbers of patients receiving outpatient or inpatient treatment for schizophrenia per month between 2010 and 2019, using National Health Insurance claims data. Facebook’s Prophet was used to fit time series models based on observations for the previous 120 months, and to predict trends over the next 36 months. @*Results@#The number of hospitalized patients per month has declined rapidly since 2015, but the monthly number of outpatient visits has steadily increased. Monthly hospital utilization has increased in patients aged ≤29 and ≥50 years, but has declined rapidly since 2014–2015 in patients in their 30s and 40s. The upward trend in overall hospital utilization has slowed considerably in recent years. These trends are expected to continue over the next few years. @*Conclusion@#This study revealed some notable changes in the hospital utilization patterns of patients with schizophrenia in recent years. There is a need to closely monitor and anticipate potential problems caused by these changing trends.

Current and Future Trends in Hospital Utilization of Patients With Schizophrenia in Korea: A Time Series Analysis Using National Health Insurance Data

Objective@#This study aimed to investigate trends in hospital utilization of patients with schizophrenia during the last 10 years in Korea and to predict future trends using time series analysis. @*Methods@#We determined the numbers of patients receiving outpatient or inpatient treatment for schizophrenia per month between 2010 and 2019, using National Health Insurance claims data. Facebook’s Prophet was used to fit time series models based on observations for the previous 120 months, and to predict trends over the next 36 months. @*Results@#The number of hospitalized patients per month has declined rapidly since 2015, but the monthly number of outpatient visits has steadily increased. Monthly hospital utilization has increased in patients aged ≤29 and ≥50 years, but has declined rapidly since 2014–2015 in patients in their 30s and 40s. The upward trend in overall hospital utilization has slowed considerably in recent years. These trends are expected to continue over the next few years. @*Conclusion@#This study revealed some notable changes in the hospital utilization patterns of patients with schizophrenia in recent years. There is a need to closely monitor and anticipate potential problems caused by these changing trends.

Network Structures of Social Functioning Domains in Schizophrenia and Bipolar Disorder: A Preliminary Study

Objective@#This study used network analyses to examine network structures reflecting interactions between specific domains of social functioning in schizophrenia (SZ) and bipolar disorder (BD). @*Methods@#We used the World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) to assess six domains of social functioning (‘cognition’, ‘mobility’, ‘self-care’, ‘getting along’, ‘life activities’, and ‘participation’) in 143 patients with SZ, 81 patients with BD, and 106 healthy subjects. We constructed regularized partial correlation networks, estimated network centrality and edge strength, tested network stability, and compared SZ and BD network structures. @*Results@#Patients with SZ showed a significantly higher level of functional disability than patients with BD. In the networks we constructed, ‘cognition’ was the most central domain of social functioning in both SZ and BD. The ‘cognition’ domain was primarily associated with the ‘getting along’ domain in the SZ network and the ‘life activities’ domain in the BD network. We found no significant group-level differences in network structures for SZ vs. BD. @*Conclusion@#Our results suggest that cognition may play a pivotal role in social functioning in both SZ and BD. In addition, domains of social functioning in SZ and BD have similar network structures despite the higher level of disability in SZ compared to BD.

Text-Mining Analyses of News Articles on Schizophrenia / 대한정신분열병학회지

Objectives@#In this study, we conducted an exploratory analysis of the current media trends on schizophrenia using text-mining methods. @*Methods@#First, web-crawling techniques extracted text data from 575 news articles in10 major newspapers between 2018 and 2019, which were selected by searching “schizophrenia” in the Naver News. We had developed document-term matrix (DTM) and/or term-document matrix (TDM) through pre-processing techniques. Through the use of DTM and TDM, frequency analysis, cooccurrence network analysis, and topic model analysis were conducted. @*Results@#Frequency analysis showed that keywords such as “police,” “mental illness,” “admission,” “patient,” “crime,” “apartment,” “lethal weapon,” “treatment,” “Jinju,” and “residents” were frequently mentioned in news articles on schizophrenia. Within the article text, many of these keywords were highly correlated with the term “schizophrenia” and were also interconnected with each other in the co-occurrence network. The latent Dirichlet allocation model presented 10 topics comprising a combination of keywords: “police-Jinju,” “hospital-admission,” “research-finding,” “care-center,” “schizophrenia-symptom,” “society-issue,” “family-mind,” “woman-school,” and “disabled-facilities.” @*Conclusion@#The results of the present study highlight that in recent years, the media has been reporting violence in patients with schizophrenia, thereby raising an important issue of hospitalization and community management of patients with schizophrenia.

Factors Affecting Admission Type in Patients with Schizophrenia Spectrum / 신경정신의학

OBJECTIVES: This study examined the admission type and its related factors among patients with psychotic disorders defined based on the revised mental health welfare law. METHODS: This study was conducted on a total of 100 patients diagnosed on the schizophrenia spectrum and other psychotic disorders. The admission type and sociodemographic characteristics were examined. Social support, psychopathology, excitement, insight, and social functioning were evaluated using the Social Support Scale, Positive and Negative Syndrome Scale (PANSS), PANSS excitement component, Brief Psychiatric Rating Scale, Global Assessment Functioning Scale, Strauss-Carpenter scale, Korean version of the Scale to Assess Unawareness of Mental Disorder, and Korean version of Beck Cognitive Insight Scale. RESULTS: The severity of psychotic symptoms, excitement, social functioning, and insight were significantly different between involuntary and voluntary admissions (p<0.05). Excitement and insight were found to be factors affecting the admission type (p<0.05). CONCLUSION: Excitement and insight were factors mainly accounting for the admission type in patients with psychotic disorder. This study could be helpful in improving clinical decision-making and community mental health care.

Prevalence of Metabolic Syndrome in Patients with Schizophrenia in Korea: A Multicenter Nationwide Cross-Sectional Study

OBJECTIVE: We designed a nationwide study with limited exclusion criteria to investigate the prevalence of metabolic syndrome (MetS) in Korea and its relationship with antipsychotic medications. METHODS: This multicenter, cross-sectional, and observational study included patients diagnosed with schizophrenia or schizoaffective disorder. Sixteen hospitals enrolled 845 patients aged 18 to 65 years prescribed any antipsychotic medication between August 2011 and August 2013. MetS was diagnosed using the criteria of the modified Adult Treatment Panel III of the National Cholesterol Education Program with the Korean abdominal obesity definition (waist circumference ≥85 cm in women, ≥90 cm in men). RESULTS: The prevalence of MetS in all patients was 36.5% and was significantly higher in men than women (men, 40.8%; women, 32.2%) and was significantly correlated with age [odds ratio (OR) 1.02] and duration of illness (OR 1.03). The prevalence of MetS across antipsychotic drugs in the major monotherapy group was as follows: 18.8% for quetiapine, 22.0% for aripiprazole, 33.3% for both amisulpride and paliperidone, 34.0% for olanzapine, 35% for risperidone, 39.4% for haloperidol, and 44.7% for clozapine. CONCLUSION: The prevalence of MetS is very high in patients with schizophrenia or schizoaffective disorder. Screening and monitoring of MetS is also strongly recommended.

Temperament and Character Traits, Heart Rate Variability and Occupational Stress in New Nursing Employees / 신경정신의학

OBJECTIVES: Nursing is a job with high stress. This study investigated the relationship between temperament and character traits, heart rate variability, and the severity of occupational stress in new nursing employees. METHODS: Ninety-seven nurses newly employed in a Seoul Medical Center from April 2014 to September 2015 were included to the study. Before beginning employment, all subjects were asked to complete a sociodemographic questionnaire and Temperament and Character Inventory (TCI). After they were employed for a month, we administered a heart rate variability test and Korean Occupational Stress Scale (KOSS). RESULTS: Harm avoidance (r=0.334, p=0.001), self-transcendence (r=0.224, p=0.028) and KOSS scores were positively correlated. Self-directedness (r=-0.278, p=0.006) and cooperativeness (r=-0.263, p=0.009) were negatively correlated with KOSS scores. In multiple regression analyses, harm avoidance and cooperativeness were risk factors for severe occupational stress. Physical parameters of total power (r=0.303, p=0.003), very low frequency (VLF ; r=0.318, p=0.002), and standard deviation of the NN interval (r=0.220, p=0.030) were significantly associated with higher KOSS scores. In multiple regression analysis, VLF was significant correlated with KOSS scores. CONCLUSION: Individual factors, such as personality trait or autonomic function, may affect the occupational stress vulnerability on this study. Harm avoidance, cooperativeness in TCI parameters are associated with severity of the occupational stress.

Changes of Appetite and Eating Behavior in Bipolar Disorder Patients: Measurement with General-Food Craving Questionnaire-Trait and the Drug-Related Eating Behavior Questionnaire

OBJECTIVES: In the current study, we quantitatively estimated changes in appetite and eating behavior of bipolar disorder patients during the pharmacotherapy. We also investigated their contribution to the weight gain and their association with specific food-craving characteristics of the patients. METHODS: Subjects included forty-one bipolar disorder patients and fifty-six controls. Currently sustained natures of food craving were assessed using the General-Food Craving Questionnaire-Trait (G-FCQ-T) and changes in appetite and eating behavior were measured using the Drug-Related Eating Behavior Questionnaire (DR-EBQ). RESULTS: Compared to the control group, the patients' group showed significantly higher body mass index (t=2.028, p=0.045). The patients' group had significantly higher 'Preoccupation with food' factor score of G-FCQ-T (p=0.016) than that of the control group. Hierarchical multiple regression analysis showed that only 'preoccupation with food' factor independently predicted psychotropic medication-induced appetite change. CONCLUSIONS: Appetite change while receiving psychotropic medication seems to be related to the weight-gain and associated with craving natures of 'preoccupation with food' in bipolar disorder. Appetite and/or eating behavioral changes measured by G-FCQ-T and DR-EBQ could be regarded as an important mediating factor in future studies exploring biological mechanisms of weight gain related with pharmacotherapy for bipolar disorder.

Factor Structure of the Neurocognitive Tests: An Application of the Confirmative Factor Analysis in Stabilized Schizophrenia Patients

The purpose of the present study was to identify the factor structure of neurocognitive tests used on schizophrenia patients by using the confirmative factor analysis, and to assess the factor score differences of schizophrenia patients and healthy controls. Comprehensive neurocognitive tests were administered to stabilized schizophrenia patients (N=114) and healthy controls (N=120). In the results of factor analyses on patients, the multifactorial-6-factor model, which included the speed of processing, working memory, verbal learning and memory, visual learning and memory, attention/vigilance, and reasoning/problem solving as suggested by the Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS), showed the better goodness of fit than any of the other models tested. And assessing the group differences of factor scores, we found the patients performed worse than the controls in all factors, but the result showed meaningful variations of impairments across the cognitive factors. Our study identifies the six major domains with multifactorial structure of cognitive abilities in schizophrenia patients and confirms the distinctive impairment patterns of each cognitive domain. These results may have utility in better understanding the pathology of schizophrenia as well as in genetic studies.

Seasonal Changes in Mood and Behavior and Associated Factors of Seasonality in Korean Bipolar Disorder Patients and Normal Controls

OBJECTIVES: Recurrence of mood episodes associated with a specific season has been described in various mood disorders. Seasonal change in mood and behavior as a lifetime trait is also observed in healthy individuals. This study aimed at comparing the lifetime trait of seasonal variations of mood and behavior between bipolar disorder patients and controls as well as investigating associated factors of seasonality. METHODS: Subjects were ninety-four clinically stable patients with bipolar disorder and 188 age- and sex-matched healthy controls. Seasonality of mood and behavior was assessed retrospectively on lifetime basis using Seasonal Pattern Assessment Questionnaire(SPAQ). RESULTS: The patient group showed a higher median global seasonality score(GSS) of SPAQ and a higher rate of seasonal affective disorder(SAD) compared to the control group(p < 0.0001). For subjects showing prominent seasonality, the seasonal symptom profile and seasonal pattern was similar in both patient and control groups. In addition to the diagnosis, female gender was shown to be a predictor of seasonality in the multiple linear regression analysis(p = 0.045). CONCLUSION: This study suggests that lifetime trait of seasonality may be related to the susceptibility of bipolar disorder.

Fever Associated with Clozapine Administration: Incidence, Clinical Characteristics, and Related Factors / 대한정신약물학회지

OBJECTIVE: This study aims at investigating the incidence, clinical nature and associated clinical characteristics of the clozapine-induced fever. METHODS: Retrospective review of hospital records was performed for 56 inpatients who had started to take clozapine and stayed at the hospital for four or more weeks after the initiation of clozapine treatment. RESULTS AND CONCLUSION: Clozapine-induced fever was developed in 31% of the patients. The mean peak temperature was 39degrees C and the mean duration of the fever was 3 days. Fever was developed average of 11 days after the initiation of clozapine treatment. All the patients were recovered without discontinuation of clozapine. Demographic variables, the clinical response to clozapine, other drugs administered with clozapine, and the presence of other adverse effects of clozapine were not associated with the clozapine-induced fever.

Growth and Development of Infants Fed Soy-Based Formulas over 3 Months / 대한지역사회영양학회지

The objective of this study was conducted to investigate growth and development status of infants fed soy-based formulas over 3 months. The height and weight were measured and Z-scores were calculated by using standard of the same age groups. Their mothers were interviewed using questionnaires including general and environmental characteristics, total food intakes, soy based formula intakes and Ewha infant development screening test. Main results were as follows: 1) Nutrient intake levels of subjects were similar to or more than the level of Korean Recommended Dietary Allowances except for intakes of vitamin E (79.89% RDA), and the average status of nutrient intakes of infants were fairly good. 2) Z-scores of height for age (HAZ) and Z-scores of weight for age (WAZ), Kaup index, WLI and Ewha Infant Developmental Screening Test score of subjects were in the normal growth range. 3) There were no significant differences among soy based formula intake percentile groups in HAZ, WAZ, Kaup index, WLI and Ewha Infant Developmental Screening Test score. 4) Total energy intake was positively correlated with HAZ (p < 0.01), WAZ (p < 0.01), and WLI (p < 0.05) in infants less than 12 month. Also, soy based formula energy intake was positively correlated with HAZ (p < 0.05) in infants less than 12 month. However, energy and soy based formula intake levels of infants over 12 month were not significant among variables. Considering results of this study, infants fed soy-based formulas over 3 months showed normal growth and development status. Further studies are needed to evaluate long-term growth and development in infants fed soy based formulas.

A Virulent Strain of Salmonella enterica Serovar London Isolated in Infants with Enteritis Traced by Active Surveillance and Molecular Epidemiological Study

A total of 74 isolates of Salmonella enterica serovar London were collected through the Laboratory-Based Diarrheal Diseases Surveillance in 2000-2001. In order to characterize the isolates and investigate the source of the epidemic, we performed antimicrobial susceptibility tests and XbaI Pulsed-field gel electrophoresis (PFGE) of 44 Salmonella London isolates. Forty isolates were from feces of infants and four isolates were from adults aged 30, 52, 54, and 59 yr. Two subtypes were identified: a tetracycline-susceptible A 0 PFGE pattern and a tetracyclineresistant A 1 PFGE pattern. Interestingly, the isolates from all infants and one 30-yr-old adult were A 0 PFGE pattern and tetracycline-susceptible. Furthermore, the A 0 PFGE pattern strain was approximately 2 times more virulent than the A 1 PFGE pattern strain, according to the results of in vitro invasion assay using J774A.1 macrophage-like cells. These results indicate that the active surveillance with molecular epidemiological tools would be valuable for promptly finding new epidemic strains. Our results also suggested that the virulent Salmonella London strain might infect the infants through a common contaminated source.