Objectives: In this study, we aimed to compare the genetic architecture of schizophrenia (SCZ) and bipolar disorder (BD) in a Korean population by analyzing polygenic risk scores (PRS) derived from large-scale psychiatric disorder genome-wide association study data, based on genetic information collected from SCZ, BD, and healthy control groups. Methods: The study included 713 Korean patients with SCZ, 1,317 with BD, 526 healthy controls. Genotyping was performed using the Korean Biobank Array. PRS-continuous shrinkage method was used to calculate the PRS. Analysis of covariance (ANCOVA) was conducted to determine the association between SCZ or BD disorder and PRS after adjusting for sex. Results: ANCOVA revealed significant differences in PRS values by diagnosis for PRS for SCZ (F=215.281, p<0.001), PRS for BD (F=13.811, p<0.001), and PRS for major depressive disorder (F=6.042, p=0.002). Post-hoc analysis showed that PRS for SCZ was highest in SCZ, followed by BD, and healthy controls. PRS for BD was elevated in both BD and SCZ compared to healthy controls. Conclusion Our study revealed quantitative differences in genetic architecture between SCZ and BD compared to healthy controls, while also suggesting a shared genetic background between the two disorders.

Background: Early trauma is known to be a risk factor of suicide-related behavior. On the other hand, people who attempt suicide using a fatal method are reported to be more likely to complete suicide. In this study, we assumed that early trauma affects an individual's temperament and character and thereby increases the risk of a fatal method of suicide attempts. Methods: We analyzed 92 people with a history of previous suicide attempts. We compared the Temperament and Character Inventory-Revised scores between the groups with and without early trauma, and between the groups with and without a history of suicide attempt using fatal methods through an analysis of covariance with age, sex, and presence of a psychiatric history as covariates. A mediation analysis was conducted of the relationship between early trauma and fatal methods of suicide attempt with self-transcendence as a mediator. Results: Higher self-transcendence was reported in the fatal group (27.71 ± 13.78 vs. 20.97 ± 12.27, P = 0.010) and the early trauma group (28.05 ± 14.30 vs. 19.43 ± 10.73, P = 0.001), respectively. The mediation model showed that self-transcendence mediates the relationship between early trauma and fatal methods of suicide attempt. The 95% confidence intervals for the direct and indirect effect were (−0.559, 1.390) and (0.026, 0.947), respectively. Conclusion Self-transcendence may mediate the relationship between early trauma and fatal methods of suicide attempt. Self-transcendence may be associated with unhealthy defenses and suicidal behavior for self-punishment and may constitute a marker of higher suicide risk.

Objective: Bipolar disorder (BD) is complex genetic disorder. Therefore, approaches using clinical phenotypes such as biological rhythm disruption could be an alternative. In this study, we explored the relationship between melatonin pathway genes with circadian and seasonal rhythms of BD. Methods: We recruited clinically stable patients with BD (n=324). We measured the seasonal variation of mood and behavior (seasonality), and circadian preference, on a lifetime basis. We analyzed 34 variants in four genes (MTNR1a, MTNR1b, AANAT, ASMT) involved in the melatonin pathway. Results: Four variants were nominally associated with seasonality and circadian preference. After multiple test corrections, the rs116879618 in AANAT remained significantly associated with seasonality (corrected p=0.0151). When analyzing additional variants of AANAT through imputation, the rs117849139, rs77121614 and rs28936679 (corrected p=0.0086, 0.0154, and 0.0092) also showed a significant association with seasonality. Conclusion This is the first study reporting the relationship between variants of AANAT and seasonality in patients with BD. Since AANAT controls the level of melatonin production in accordance with light and darkness, this study suggests that melatonin may be involved in the pathogenesis of BD, which frequently shows a seasonality of behaviors and symptom manifestations.

Objective: Bipolar disorder (BD) is complex genetic disorder. Therefore, approaches using clinical phenotypes such as biological rhythm disruption could be an alternative. In this study, we explored the relationship between melatonin pathway genes with circadian and seasonal rhythms of BD. Methods: We recruited clinically stable patients with BD (n=324). We measured the seasonal variation of mood and behavior (seasonality), and circadian preference, on a lifetime basis. We analyzed 34 variants in four genes (MTNR1a, MTNR1b, AANAT, ASMT) involved in the melatonin pathway. Results: Four variants were nominally associated with seasonality and circadian preference. After multiple test corrections, the rs116879618 in AANAT remained significantly associated with seasonality (corrected p=0.0151). When analyzing additional variants of AANAT through imputation, the rs117849139, rs77121614 and rs28936679 (corrected p=0.0086, 0.0154, and 0.0092) also showed a significant association with seasonality. Conclusion This is the first study reporting the relationship between variants of AANAT and seasonality in patients with BD. Since AANAT controls the level of melatonin production in accordance with light and darkness, this study suggests that melatonin may be involved in the pathogenesis of BD, which frequently shows a seasonality of behaviors and symptom manifestations.

Background: Early trauma is known to be a risk factor of suicide-related behavior. On the other hand, people who attempt suicide using a fatal method are reported to be more likely to complete suicide. In this study, we assumed that early trauma affects an individual's temperament and character and thereby increases the risk of a fatal method of suicide attempts. Methods: We analyzed 92 people with a history of previous suicide attempts. We compared the Temperament and Character Inventory-Revised scores between the groups with and without early trauma, and between the groups with and without a history of suicide attempt using fatal methods through an analysis of covariance with age, sex, and presence of a psychiatric history as covariates. A mediation analysis was conducted of the relationship between early trauma and fatal methods of suicide attempt with self-transcendence as a mediator. Results: Higher self-transcendence was reported in the fatal group (27.71 ± 13.78 vs. 20.97 ± 12.27, P = 0.010) and the early trauma group (28.05 ± 14.30 vs. 19.43 ± 10.73, P = 0.001), respectively. The mediation model showed that self-transcendence mediates the relationship between early trauma and fatal methods of suicide attempt. The 95% confidence intervals for the direct and indirect effect were (−0.559, 1.390) and (0.026, 0.947), respectively. Conclusion Self-transcendence may mediate the relationship between early trauma and fatal methods of suicide attempt. Self-transcendence may be associated with unhealthy defenses and suicidal behavior for self-punishment and may constitute a marker of higher suicide risk.

OBJECTIVES: Genome-wide association studies (GWASs) and meta-analyses indicate that single-nucleotide polymorphisms (SNPs) in the a-1C subunit of the L-type voltage-dependent calcium channel (CACNA1C) gene increase the risk for schizophrenia and bipolar disorders (BDs). We investigated the association between the genetic variants on CACNA1C and schizophrenia and/or BDs in the Korean population. METHODS: A total of 582 patients with schizophrenia, 336 patients with BDs consisting of 179 bipolar I disorder (BD-I) and 157 bipolar II disorder (BD-II), and 502 healthy controls were recruited. Based on previous results from other populations, three SNPs (rs10848635, rs1006737, and rs4765905) were selected and genotype-wise association was evaluated using logistic regression analysis under additive, dominant and recessive genetic models. RESULTS: rs10848635 showed a significant association with schizophrenia (p=0.010), the combined schizophrenia and BD group (p=0.018), and the combined schizophrenia and BD-I group (p=0.011). The best fit model was dominant model for all of these phenotypes. The association remained significant after correction for multiple testing in schizophrenia and the combined schizophrenia and BD-I group. CONCLUSION: We identified a possible role of CACNA1C in the common susceptibility of schizophrenia and BD-I. However no association trend was observed for BD-II. Further efforts are needed to identify a specific phenotype associated with this gene crossing the current diagnostic categories.
Bipolar Disorder ; Calcium Channels ; Genetic Association Studies ; Genome-Wide Association Study ; Humans ; Logistic Models ; Models, Genetic ; Phenotype ; Polymorphism, Single Nucleotide ; Schizophrenia

OBJECTIVE: This study explores the feasibility and psychometric properties of the Korean version of the Bipolar Depression Rating Scale (BDRS) in adolescents with Early-onset bipolar disorders. METHODS: Fifty-three participants (aged 13–18) with early-onset bipolar disorders (40 depressed and 18 euthymic, 5 patients were assessed at depressed state and reassessed after remission) were recruited. All participants were assessed using the BDRS, the Hamilton Depression Rating Scale (HAM-D), the Montgomery-Asperg Depression Rating Scale (MADRS), the Young Mania Rating Scale (YMRS), and the Modified Overt Aggression scale (MOAS). RESULTS: BDRS exhibited good internal validity and significant correlations with the HAM-D and the MADRS. In item to scale correlations, all items on the BDRS were significantly correlated with the BDRS total scores except for ‘increased motor drive’ and ‘increased speech’, ‘depressed mood’ and ‘worthlessness’ showed the highest mean scores and endorsement rates. BDRS score of the depressed group was significantly higher compared with the euthymic group. Three factors (i.e., psychosomatic, mood, and mixed) were identified in the principal component analysis and hierarchical cluster analysis of the BDRS. CONCLUSION: In this study, we report that the Korean version of BDRS is a feasible and reliable tool for the assessment of depression in adolescents with Early-onset bipolar disorders.
Adolescent* ; Aggression ; Bipolar Disorder* ; Depression ; Humans ; Principal Component Analysis ; Psychometrics

OBJECTIVES: To use focus-group interviews (FGI) to determine the current state of the Korean mental health service delivery system, inter-agency patient links, and identify associated problems. METHODS: The FGI were conducted by seven workers from psychiatric rehabilitation centers and community mental health centers and seven social workers from mental health hospitals. RESULTS: Within the mental health service delivery system, disconnection of the community network after discharge is considered a serious problem. The following improvement proposals are suggested : 1) the control tower should govern the community network after discharge, 2) consider insurance costs during activation of hospital links, and 3) expand information sharing related to community social facilities. With regard to non-voluntary admission and long-term hospitalization, most focus group members considered the revolving-door phenomenon to be more serious than non-voluntary admission. In order to prevent unnecessary long-term hospitalization, the FGI results indicated that the government should proactively intervene in the admission/discharge process. In addition, the following improvement proposals were suggested : 1) functional activation of the mental health review board via the reinforcement of workers' expertise, 2) expansion of local mental health centers, and 3) undertake institutional changes related to the family-related issue of preferring hospitalization over a stay at a secure facility. CONCLUSION: For the government to improve the efficiency of the mental health service delivery system, it is necessary to improve institutional linkages, expand mental health infrastructure, and develop an integrated management system.
Community Mental Health Centers ; Community Networks ; Focus Groups ; Hospitalization ; Humans ; Information Dissemination ; Insurance ; Mental Health Services* ; Mental Health* ; Psychiatric Rehabilitation ; Social Work ; Social Workers

Several studies have linked teachers' personality characteristics and sense of efficacy to stress. However, investigating the relationship between these three constructs in this context was limited. This study aims to investigate the relationship between personality, sense of efficacy and perceived stress among Korean teachers. A total of 137 teachers working in elementary, middle, and high schools located in Seoul, South Korea were recruited for the study. The participants were administered Temperament and Character Inventory, Teacher's Sense of Efficacy Scale (TSES), and Perceived Stress Scale. The TSES was negatively correlated with harm avoidance and positively correlated with persistence, self-directedness, cooperativeness, and self-transcendence. Perceived stress was positively correlated with harm avoidance and negatively correlated with persistence and self-directedness. The path analysis showed that harm avoidance directly predicted perceived stress (β=0.37, 95% CI=0.21–0.53, p=0.002), and self-directedness and persistence predicted one's sense of efficacy (β=0.18, 95% CI=0.01–0.39 and β=0.31, 95% CI=0.10–0.47), which predicted perceived stress (β=-0.21, 95% CI=-0.39 to -0.02). The results of the present study indicate that harm avoidance might be associated with stress-proneness, while persistence, self-directedness, and sense of efficacy might act as protective resources against stress in Korean teachers.
Humans ; Korea ; Seoul ; Temperament

OBJECTIVES: There were previous studies which indicated that attitude toward suicide is able to influence the suicide outcome in both individual and group levels. In regard to the highest suicide rate in Korea, our study aims to explore the influence that attitude toward suicide has on suicide by comparing the national attitude towards suicide with a representative sample of the general population. METHODS: The target population was 20- to 59-year-old adults from South Korea, Japan, and the United States. The panel data were divided according to gender, age, and residential area of individuals, and an email with a hyperlink to our web survey was sent to the randomly selected participants in each stratum. To measure the perceptual differences about suicide in different cultures, this study adopted the Attitudes Toward Suicide questionnaire. RESULTS: A total of 2247 subjects in three countries participated in this study. According to results from factor analysis, there were different structure of factors and included items within factors in the three countries : five factors with nineteen items in South Korea, five factors with nineteen items in the United States, and five factors with twenty-five items in Japan. With regard to permissive attitude toward suicide, the mean value of permissiveness was not significantly different among countries, but permissiveness according to education level, gender, and marital status was different in each country. CONCLUSIONS: This study is the first nationwide comparative study about attitude toward suicide with a representative sample. Our findings suggest that permissive attitude toward suicide influence the suicide phenomenon in each country ; however, its impact is not a mean score of permissiveness, but the detailed difference by various demographics.
Adult ; Demography ; Education ; Electronic Mail ; Factor Analysis, Statistical ; Health Services Needs and Demand ; Humans ; Japan* ; Korea* ; Marital Status ; Middle Aged ; Permissiveness ; Suicide* ; United States*