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This study aimed to investigate the association between gut microbiota and depressive symptoms in a large population cohort of Korean adults.Overall, 1238 participants were included in the study. Participants were categorized into depressed or non-depressed groups, based on the depressive symptoms reported on the Center for Epidemiologic Studies Rating Scale for Depression, with a cutoff score of 16, and their fecal microbiota was profiled using 16S ribosomal RNA gene sequencing. Several alpha and beta diversity measures were also estimated. The association between depressive symptoms and gut microbiota was analyzed using generalized linear models. The inferred function of the metagenomes was compared between the two groups.There were no consistent differences in alpha and beta diversity between the depressed and non-depressed groups. However, the continuous measure of depressive symptoms was inversely associated with one of four measures of alpha diversity (Shannon's diversity, p = .021). We also found a substantial difference between the depressed and non-depressed groups in the Bray-Curtis dissimilarity among the four beta diversity indices ( p = .004). Participants whose depressive symptoms exceeded a clinical cutoff score had a lower relative abundance of the genus Faecalibacterium when compared with controls (coefficient = -0.025, q = 0.047). However, the depressed group had a significantly higher abundance of the genus Oscillospira than did the non-depressed group (coefficient = 0.002, q = 0.023).Our findings contribute to the identification of potential relationships between the gut microbiota and depressive symptoms and provide useful insights for developing microbiota-based interventions for patients with depressive symptoms.

This study aimed to optimize and evaluate self-assembled liquid crystalline nanoparticles (SALCs) prepared from phospholipids and oleic acid for enhancing the absorption of Ω-3s. We explored the structure and optimal formulation of SALCs, which are composed of Ω-3 ethyl ester (Ω-3 EE), phospholipids, and oleic acid, using a ternary diagram and evaluated the improvement in Ω-3 dissolution, permeation, and oral bioavailability. The in vitro dissolution and pharmacokinetics of Ω-3 SALCs were compared with those of Omacor soft capsules (as the reference). The shape of the liquid crystal was determined according to the composition of phospholipids, oleic acids, and Ω-3s and was found to be in cubic, lamellar, and hexagonal forms. The dissolution rates of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) obtained from Ω-3 SALCs were 1.7 to 2.3-fold higher than those of the Omacor soft capsules. Furthermore, a pharmacokinetic study in male beagle dogs revealed that Ω-3 SALCs increased the oral bioavailability of Ω-3 EE by 2.5-fold for EPA and 3.1-fold for DHA compared with the reference. We found an optimal formulation that spontaneously forms liquid crystal-based nanoparticles, improving the bioavailability of EPA and DHA, not found in the existing literature. Our findings offer insight into the impact of nanoparticle phase on the oral delivery of oil-soluble drugs and provide a novel Ω-3 EE formulation that improves the bioavailability of EPA and DHA.

Objective The risk of suicide is assessed by identifying the relationship between alcohol-use patterns and suicidal ideation in Korean employees.Methods The study involved 13,858 employees who underwent workplace mental health screening at the Workplace Mental Health Institute of Kangbuk Samsung Hospital over a 6-year period between 2014 and 2019. Analysis was performed separately for Alcohol Use Disorders Identification Test-Korea (AUDIT-K) items related to the frequency/volume of alcohol consumption (items 1 to 3, AUDIT-C) and those regarding alcohol dependence/related problems (items 4 to 10, AUDIT-D/P). Subjects were then classified into three groups on the basis of the presence or absence of clinical depression and suicidal ideation. The groups’ sociodemographic factors and clinical features of depression, anxiety, and alcohol-use patterns were analyzed with a chi-square test as well as one-way analysis of variance, followed by a post hoc test using the Bonferroni correction.Results AUDIT-K and AUDIT-D/P scores were significantly associated with the presence or absence of clinical depression as well as the presence or absence of suicidal ideation (p

Purpose: This study aimed to analyze the alcohol use patterns that may influence suicide attempt in employees who have suicidal ideation.Methods: The 15,199 participants were classified into three groups according to suicide risk severity. Participant scores on the Alcohol Use Disorders Identification Test-Korea (AUDIT-K), subscale for drinking amount/frequency (AUDIT-C, items 1–3), subscale for dependence/related problems (AUDIT-D/P, items 4–10), and other sociodemographic and psychiatric scales were analyzed between the groups using one-way analysis of variance (ANOVA) and the chi-square test, followed by post hoc analysis using the Bonferroni correction.Results: A statistically significant difference between all three groups was observed for AUDIT-D/P scores after post hoc analysis (P < 0.001), indicating an increasing trend for greater suicide risk. This trend was present in both sexes and across all age groups above 30 years old.Conclusion: Alcohol dependence/related problems are significantly associated with suicide attempt among employees. Assessing and preventing suicide risk according to these issues may minimize socioeconomic losses due to suicide.

Objective The pathology of post-traumatic stress disorder (PTSD) is associated with changes in brain structure and function, especially in the amygdala, medial prefrontal cortex, hippocampus, and insula. Survivors of tragic accidents often experience psychological stress and develop post-traumatic stress symptoms (PTSS), regardless of the diagnosis of PTSD. This study aimed to evaluate electroencephalographic changes according to PTSS in victims of a single traumatic event. Methods This study enrolled 60 survivors of the Sewol ferry disaster that occurred in 2014 from Danwon High School and collected electroencephalographic data through 19 channels twice for each person in 2014 and 2015 (mean 451.88 [standard deviation 25.77] days of follow-up). PTSS was assessed using the PTSD Checklist-Civilian Version (PCL-C) and the participants were divided into two groups according to the differences in PCL-C scores between 2014 and 2015. Electroencephalographic data were converted to three-dimensional data to perform low-resolution electrical tomographic analysis. Results Significant electroencephalographic changes over time were observed. The group of participants with worsened PCL-C score showed an increased change of delta slow waves in Brodmann areas 13 and 44, with the largest difference in the insula region, compared to those with improved PCL-C scores. Conclusion Our findings suggests that the electrophysiological changes in the insula are associated with PTSS changes.

Objective Many patients with major depressive disorder (MDD) suffer from residual symptoms without achieving remission. However, pharmacologic options for residual symptoms of MDD have been limited. This study aimed to investigate benefit of aripiprazole augmentation in the treatment of residual symptoms in the patients with partially remitted MDD. Methods We retrospectively analyzed the 8-week medical records of the patients. The enrolled patients did respond to treatment of antidepressant but were not remitted. The range of 17-item Hamilton Depression Rating Scale (HAMD) total score of the subjects were 8 to 15 points. All patients were currently taking antidepressants when they started aripiprazole. The primary endpoint was the mean change of Clinically Useful Depression Outcome Scale (CUDOS). Secondary endpoint measures were HAMD, Clinical Global Impression-severity (CGI-S) scores, Patient Health Questionnaire-15 (PHQ-15), Beck Anxiety Inventory (BAI), Perceived Deficit Questionnaire-depression (PDQ-D), Sheehan Disability Scale (SDS) and General Health Questionnaire/Quality of Life-12 (GHQ/QL-12). Results A total of 134 medical records were analyzed. The changes of CUDOS, HAMD, CGI-S, BAI, PHQ-15, PDQ-D, SDS and GHQ/QL-12 from baseline to the endpoint were -7.93, -3.29, -0.80, -4.02, -2.05, -4.35, -4.77 and -2.82, respectively (all p < 0.001). At the endpoint, the newly remitted subjects rate by HAMD score criteria were approximately 46%. Conclusion Our preliminary findings have presented the effectiveness of aripiprazole augmentation for residual symptoms of partially remitted MDD patients in routine practice. This study assures subsequent well-controlled studies of the possibility of generalizing the above promising outcome in the future.

The aim of this study is to identify occupational stress associated with the development of new-onset anxiety symptoms and the dose-response relationship between sleep duration and the onset of anxiety symptoms. Data from 29,251 healthy employees who had undergone at least two comprehensive health examinations at Kangbuk Samsung Hospital Health Screening Center were analysed. Anxiety symptoms were assessed using the Beck Anxiety Inventory. Occupational stress and sleep duration were measured using a self-reported questionnaire about total sleep time and the Korean Occupational Stress Scale-Short Form (KOSS-SF), respectively. Flexible parametric proportional hazards model used to estimate the hazard ratios. Compared with the groups without case-level anxiety, discomfort in an organizational climate, high job demands, job insecurity, organizational injustice and lack of reward were associated with the onset of case-level anxiety. Compared with less than 6 hr of sleep per day, the beneficial level of sleep duration was 7 ≤ to

Objective The aim of study is to investigate the relationship between serum vitamin D, c-reactive protein (CRP) levels, and anxiety symptoms.Methods Serum vitamin D and CRP levels of 51,003 Korean adult participants were collected retrospectively. Anxiety symptoms were assessed using the Korean version of Beck Anxiety Inventory. Logistic regression was used to estimate the odds ratio (ORs) of anxiety symptoms by serum vitamin D and CRP levels. The regression was adjusted for covariates, and each model was adjusted mutually for vitamin D and CRP levels.Results Compared with sufficient vitamin D levels (≥20 ng/mL), insufficient (10–19.99 ng/mL) and deficient (

Maintaining adequate levels of sleep and physical activity (PA) as self-help for the prevention of new-onset anxiety symptoms is becoming more important.A cohort study was performed with 134,957 adults, free of anxiety symptoms at baseline who underwent at least two comprehensive health screening examinations between 2012 and 2017. At baseline, the amount of PA was measured using the International Physical Activity Questionnaire-Short Form and sleep duration per day was assessed using a self-report questionnaire. The study's end point was new-onset anxiety symptoms, defined as a Beck Anxiety Inventory score of ≥19.During 361,969 person-years of follow-up, 5086 participants developed case-level anxiety. Compared with a reference (0-600 METs-min/wk), a U-shaped relationship was observed between PA and case-level anxiety. The most beneficial levels of PA for reducing incident anxiety symptoms were higher in men than women (men: 1800-3000 METs-min/wk HR, 0.88 [95% CI, 0.78-0.81], 3000-6000 METs-min/wk HR, 0.81 [95% CI, 0.70-0.93]; women: 600-1,200 METs-min/wk HR, 0.86 [95% CI, 0.76-0.98]). In comparison with a reference (6 h), the relationship between sleep duration and case-level anxiety also had a U-shaped pattern. The optimal sleep duration for decreasing the onset of case-level anxiety was 7-8 h, regardless of sex (men: HR, 0.75 [95% CI, 0.63-0.90]; women; HR, 0.61 [95% CI, 0.54-0.70]).PA, sleep duration, and anxiety symptoms were measured using self-report questionnaires.The results of this study revealed the appropriate levels of PA and total sleep time for reducing incident anxiety symptoms.

Aims There has been increasing evidence of hormonal changes during reproductive events that lead to mood changes. However, studies on the severity of psychological problems according to the menopausal stage are limited. Thus, this study aimed to investigate the association between menopausal stages, depression and suicidality. Methods A total of 45 177 women who underwent regular health check-ups between 2015 and 2018 at Kangbuk Samsung Hospital were included. Participants were stratified into four groups (pre-menopause, early transition, late transition and post-menopause) based on the Stages of Reproductive Aging Workshop Criteria. The Center for Epidemiological Studies-Depression scale (CESD) was used to evaluate depressive symptoms, and the degree of depressive symptoms was classified as moderate (CESD score 16–24) or severe (CESD score ⩾ 25). To measure suicide risk, we administered questionnaires related to suicidal ideation. Results Overall, the prevalence of CESD scores of 16–24 and ⩾ 25 was 7.6 and 2.8%, respectively. Menopausal stages were positively associated with depressive symptoms in a dose-dependent manner. Multivariable-adjusted prevalence ratios (PRs, 95% confidence intervals) for CESD scores of 16–24 comparing the stages of the early menopausal transition (MT), late MT and post-menopause to pre-menopause was 1.28 (1.16–1.42), 1.21 (1.05–1.38) and 1.58 (1.36–1.84), respectively. The multivariable-adjusted PRs for CESD scores ⩾ 25 comparing the stages of the early MT, late MT and post-menopause to pre-menopause were 1.31 (1.11–1.55), 1.39 (1.12–1.72), 1.86 (1.47–2.37), respectively. In addition, the multivariable-adjusted PRs for suicidal ideation comparing the early MT, late MT and post-menopause stages to the pre-menopause stage were 1.24 (1.12–1.38), 1.07 (0.93–1.24) and 1.46 (1.25–1.70) (p for trend Conclusions These findings indicate that the prevalence of depressive symptoms and suicidal ideation increases with advancing menopausal stage, even pre-menopause.

Objective This study aimed to compare the efficacy and safety of escitalopram, vortioxetine, and desvenlafaxine for acute treatment of major depressive disorder (MDD) with cognitive complaint (CC).Methods A total of 129 patients with MDD who also complained of CC were randomized evenly to either escitalopram, vortioxetine, or desvenlafaxine group and underwent a multi-center, six-week, rater-blinded, and head-to-head comparative trial. Differences in depressive symptoms following treatment were measured using the Hamilton Depression Rating Scale (HAMD) and the Montgomery-Åsberg Depression Rating Scale (MADRS). Subjective cognitive function and the presence of adverse events were assessed.Results The three antidepressant treatment groups did not show significant differences in the improvement of depressive symptoms as measured by HAMD and MADRS. Desvenlafaxine treatment was associated with a superior treatment response rate in depressive symptoms compared to vortioxetine or escitalopram treatment. However, no significant differences were found in the remission rate of depressive symptoms. The three antidepressant treatment groups did not show significant differences in the improvement of CC. Adverse profiles of each treatment group were tolerable, with no significant differences.Conclusion In acute antidepressant treatment for MDD with CC, escitalopram, vortioxetine, and desvenlafaxine presented similar efficacy in relief of depressive symptoms; however, desvenlafaxine was associated with a superior treatment. Further studies are needed to confirm these results by investigating the therapeutic efficacy and safety profile of long-term antidepressant treatment of MDD with CC (Clinical Trial Registry, http://cris.nih.go.kr/cris/en/: KCT0002173).

Objective The aim of this study is to determine the dose-response relationship between physical activity and anxiety symptoms. Methods We included data of 124,434 participants who had comprehensive health-screening examinations from January 1st, 2012, to December 31st, 2016, in Kangbuk Samsung Hospital, Seoul and Suwon, South Korea. We measured the level of physical activity using the International Physical Activity Questionnaire-short form (IPAQ-SF) and estimated anxiety symptoms using the Beck Anxiety Inventory (BAI). BAI scores of 19 and above were defined as cases. Logistic regression was used to analyze the association between physical activity and BAI-defined anxiety. Furthermore, we assessed whether sex differences might affect the relationship between physical activity and BAI-defined anxiety by stratifying our data. Results Compared with the sedentary group (0-600 METs-min/week), individuals achieving 600-6,000 METs-min/wk had a significantly lower risk of BAI-defined anxiety with a U-shaped relationship in general adults. After stratifying our data by sex, we found that optimal ranges of physical activity were 600-9,000 METs-min/wk for men, but 1,200-3,000 METs-min/wk for women. Conclusion We identified a U- or J-shaped association between physical activity and anxiety symptoms, suggesting an optimal dose and upper limit of physical activity for decreasing anxiety symptoms. Optimal levels and upper limits of physical activity for reducing anxiety symptoms were higher for men than for women.

Objective The aim of this study was to identify work stress associated with the development of suicidal ideation with a focus on gender and age differences among Korean employees. Methods The data of 95 356 healthy employees aged >18 years who had undergone at least two comprehensive health examinations at Kangbuk Samsung Hospital Health Screening Center, South Korea, were analyzed. Risk of suicidal ideation was assessed using a self-reported questionnaire examining suicidal ideation during the past year. Work stress was measured using the Korean Occupational Stress Scale-Short Form. A Cox proportional hazards model was used to examine relationship between work stress and suicidal ideation. Considering gender and age differences in the association between work stress and suicidal ideation, the data were stratified by gender and age groups. Results During 289 706 person-years of follow-up, suicide ideation was identified in 3 460 participants. For male workers, high job demands and lack of reward were associated with the risk of suicidal ideation in young adults and midlife decade group. Job insecurity was associated with the risk of suicidal ideation in midlife decade and middle-aged and older adulthood. Organizational injustice was associated with the risk of suicidal ideation in middle-aged and older adulthood. Discomfort in an organizational climate was associated with the development of suicidal ideation in all age groups. For female workers, organizational injustice and discomfort in an organizational climate were associated with the risk of suicidal ideation in early adulthood. Conclusion The results suggested that certain work stressors are risk factors of suicidal ideation. Gender and age differences in components of work stress associated with suicidal ideation were also observed.

This study examined the validity and reliability of the Korean version of the Generalized Anxiety Disorder-7 (GAD-7) scale. The GAD-7 was standardized with data from 112 patients at a psychiatric outpatient clinic. The GAD-7 revealed high internal consistency, good test-retest reliability, and convergent validity. The ROC analysis resulted in poor sensitivity and specificity for detecting anxiety disorders in a psychiatric setting. The GAD-7 may not be useful in diagnosing anxiety disorders in a psychiatric setting, even though it appears to be a reliable, efficient, and valid measurement tool for evaluating anxiety symptoms.

This chapter reviews the roles of cytokines and glial cells in chronic pain and in psychiatric disorders, especially depression. One important role of cytokines is in communicating between activated glia and neurons, at all levels of the nervous system. This process of neuroinflammation plays important roles in pain and depression. Cytokines may also directly regulate neuronal excitability. Many cytokines have been implicated in both pain and psychiatric disorders, including interleukin-1β‎ (IL-1β‎), tumor necrosis factor-α‎, and IL-6. More generally, an imbalance between type 1, pro-inflammatory cytokines and type 2, anti-inflammatory cytokines has been implicated in both pain and psychiatric disorders. Activation of the sympathetic nervous system can contribute to both pain and psychiatric disorders, in part through its actions on inflammation and the cytokine profile.

Aims To evaluate the bidirectional relationship between blood pressure (BP) and depressive symptoms using a large prospective cohort study. Methods Prospective cohort study was performed in 276 244 adults who participated in a regular health check-up and were followed annually or biennially for up to 5.9 years. BP levels were categorised according to the 2017 American College of Cardiology and American Heart Association hypertension guidelines. Depressive symptoms were assessed using Centre for Epidemiologic Studies-Depression (CESD) questionnaire and a cut-off score of ≥25 was regarded as case-level depressive symptoms. Results During 672 603.3 person-years of follow-up, 5222 participants developed case-level depressive symptoms. The multivariable-adjusted hazard ratios (HRs) [95% confidence interval (CI)] for incident case-level depressive symptoms comparing hypotension, elevated BP, hypertension stage 1 and hypertension stage 2 to normal BP were 1.07 (0.99–1.16), 0.93 (0.82–1.05), 0.89 (0.81–0.97) and 0.81 (0.62–1.06), respectively (p for trend p for trend p for trend Conclusions In this large cohort study of young and middle-aged individuals, higher BP levels were independently associated with a decreased risk for developing case-level depressive symptoms and depressive symptoms were also associated with incident hypertension. Further studies are required to elucidate the mechanisms underlying the bidirectional association between BP levels and incident depression.

Despite the fact that the lifetime and yearly prevalence rates of mental illness continue rising, such diseases have only been acknowledged as involved in workplace health issue since the 2000s. Additionally, while the number of recognized cases of mental illnesses is rather low compared to their prevalence, they have a high likelihood of causing significant problems, including fatalities. Many workers are terrified of losing their jobs due to mental illness and therefore attempt to hide their mental health problems. For this reason, clinicians involved in occupational and environmental medicine should focus on interviews or screenings to identify such hidden mental health problems. More specifically, it would be helpful to evaluate job stress and depression in workplaces to ensure appropriate preventive actions and thereby reduce the prevalence of mental illness. Job stress not only causes mental illness and dissatisfaction with work, but also can increase the prevalence and morbidity of medical diseases, as well as other physical health problems. Depression is a major contributor to work loss and absence with effects surpassing almost all of the chronic medical disorder. These facts show why measure of job stress and depression should be highlighted in the occupational settings. This article introduces a variety of assessment tools to examine mental health, particularly stress and depression, in workplaces. These tools can be used by clinicians or professionals involved in the mental health, occupational safety, or health service fields for running diagnostics or screening tests.

Background Recently, neuroinflammation and the immune-kynurenine pathway have received increased attention in the psychoimmunology field of major depressive disorder (MDD), while studies related to anxiety disorders have been very limited. Objective This study reviewed possible mechanisms by which stress or inflammation modulate anxiety through tryptophan metabolism and the kynurenine pathway. Methods Relevant literature was identified through a search of MEDLINE via PubMed. Results Accumulating evidence has indicated the modulatory effects of the immune-kynurenine pathway on anxiety. The tryptophan catabolites (TRYCATs) in the kynurenine pathway imbalanced by stress or inflammation induce serotonin and melatonin deficiency, making anxiety reactions more sensitive. In addition, TRYCATs cause or sustain anxiety by acting as endogenous anxiogens or anxiolytics, an NMDA agonist or antagonist, or a free radical generator. Conclusion We hope that our understanding of the psychoimmunological mechanisms of anxiety will be expanded and anxiety-related studies will receive greater attention.

This study was performed to examine the elements that cause suicidal ideation to develop into a suicide attempt by comparing the factors related to suicidal ideation and attempt. The subjects in the study were 5982 employees, who received mental health screening from January 2016 to December 2019 in Korea. Multivariate binary logistic regression analysis was performed with suicidal ideation and suicide attempt as dependent variables respectively. While suicidal ideation was associated with both moderate and severe grades of depression and alcohol consumption, only severe grades of depression and alcohol consumption were associated with suicide attempts. Among family, interpersonal, work-related, and financial stress, which were significant predictors of suicidal ideation, only family stress predicted suicide attempts. Whereas dissatisfaction with the present, regret for the past, and hopelessness for the future were all predictors for suicidal ideation, only regret for the past was a significant predictor of suicide attempts. The distinctive impact of family stress on suicide attempts suggests that family support can play a pivotal role in suicide prevention, and the significant impact of regret for the past on suicide attempts indicates the need for a cognitive approach in a high-risk population. Finally, the substantial impact of alcohol on suicide attempts compared to suicidal ideation suggests the importance of alcohol regulation in suicide prevention.

Objective This study was aimed at evaluating the diagnostic validity of the Korean version of the Clinically Useful Depression Outcome Scale (CUDOS) with varying follow-up in a typical clinical setting in multiple centers. Methods In total, 891 psychiatric outpatients were enrolled at the time of their intake appointment. Current diagnostic characteristics were examined using the Structured Clinical Interview for DSM-IV (41% major depressive disorder). The CUDOS was measured and compared with three clinician rating scales and four self-report scales. Results The CUDOS showed excellent results for internal consistency (Cronbach’s α, 0.91), test-retest reliability (patients at intake, r=0.81; depressed patients in ongoing treatment, r=0.89), and convergent and discriminant validity (measures of depression, r=0.80; measures of anxiety and somatization, r=0.42). The CUDOS had a high ability to discriminate between different levels of depression severity based on the rating of Clinical Global Impression for depression severity and the diagnostic classification of major depression, minor depression, and non-depression. The ability of the CUDOS to identify patients with major depression was high (area under the receiver operating characteristic curve=0.867). A score of 20 as the optimal cutoff point was suggested when screening for major depression using the CUDOS (sensitivity=89.9%, specificity=69.5%). The CUDOS was sensitive to change after antidepressant treatment: patients with greater improvement showed a greater decrease in CUDOS scores (p

Psychiatric disorders are too multifactorial to be defined as a primarily inflammatory disorder, and increased inflammatory response is not specific to mental disorder only. Numerous factors are involved in neuroinflammation, and there also are many confounding variables, making it difficult to obtain consistent outcomes. Therefore, it is necessary to specify genetic, physiological, and epidemiological attributes of particular population groups vulnerable to inflammatory response as well as the disease subtypes. As of now, definitive inflammatory markers for psychiatric disorders have not been identified, but they could be very useful in patients with minimal vulnerability. In addition, it is possible to use inflammatory markers as depression biomarkers in subtypes of depression, which can serve as bases to develop medications to treat the disorder.

The aim of this study was to identify gender- and age-specific occupational stress associated with depressive symptoms among Korean employees. Data of 73,014 employees aged 18 and above who had undergone comprehensive health examinations at Kangbuk Samsung Hospital Health Screening Center, South Korea, in January 2012 and who were followed up until December 2017 were collected, and 63,959 (participation rate: 87.59%, men: 50,413, women: 13,546) were finally analyzed. A Cox proportional hazards model was used to estimate the hazard ratios and 95% confidence intervals of the relationship between occupational stress and depressive symptoms. In light of gender and age differences in the association between occupational stress and depressive symptoms, interaction and stratification by gender and age groups were tested. During 238,630 person-years of follow-up, case-level depressive symptoms developed in 4227 participants (an incident rate of 1.8%). There were gender differences in the relationship between job stress and incident depressive symptoms. For men, high job demand, job insecurity, lack of reward, and discomfort in their organizational climate were associated with incident depressive symptoms in all age groups. Insufficient job control was associated with the development of depressive symptoms only in midlife and organizational injustice only in early adulthood. For women, the results for high job demand, organizational injustice, and discomfort in an organizational climate were associated with the onset of depressive symptoms from early adulthood to the midlife decade. The results suggest gender and age differences in the relationship between occupational stress and incident depressive symptoms.

Background: The relationship between blood pressure (BP) level and depression remains controversial. We evaluated the bidirectional relationship between BP and depressive symptoms using a large prospective cohort study. Methods: Prospective cohort study was performed in 172,102 adults who participated in a regular health checkup and were followed annually or biennially for up to 5.9 years. BP levels were categorized according to the 2017 American College of Cardiology and American Heart Association hypertension guidelines. Depressive symptoms were assessed using Center for Epidemiologic Studies-Depression (CESD) questionnaire and a cut-off score of ≥25 was regarded as depression. Findings: During 672,603.3 person-years of follow-up, 5,222 participants developed depression. The multivariable-adjusted hazard ratios (HRs) [95% confidence interval (CI)] for incident depression comparing hypotension, elevated BP, hypertension stage 1, and hypertension stage 2 to normal BP were 1.07 (0.99-1.16), 0.92 (0.82-1.05), 0.88 (0.80-0.96) and 0.77 (0.58-1.01), respectively (p for trend

Psychiatric disorders are too multifactorial to be defined as a primarily inflammatory disorder, and increased inflammatory response is not specific to mental disorder only. Numerous factors are involved in neuroinflammation, and there also are many confounding variables, making it difficult to obtain consistent outcomes. Therefore, it is necessary to specify genetic, physiological, and epidemiological attributes of particular population groups vulnerable to inflammatory response as well as the disease subtypes. As of now, definitive inflammatory markers for psychiatric disorders have not been identified, but they could be very useful in patients with minimal vulnerability. In addition, it is possible to use inflammatory markers as depression biomarkers in subtypes of depression, which can serve as bases to develop medications to treat the disorder.

We aimed to investigate the associations between genetic variants of the norepinephrine transporter gene (NET, also known as SLC6A2) and diagnosis of bipolar I disorder. In addition, we examined the relationship between the genetic variants and manic and psychotic symptoms in patients with bipolar I disorder. The three SNPs rs28386840, rs2242446, and rs5569 were genotyped in 326 patients: patients with bipolar I disorder (n = 160) and a control group (n = 166). Subsequently, multivariate logistic regression analysis adjusting for age and sex was conducted to identify independent influences of the SNPs on diagnosis of bipolar I disorder. A possible association between manic and psychotic symptoms and variants of SLC6A2 was also investigated in patients with bipolar I disorder. The rs28836840 SNP in the 5’-UTR of SLC6A2 was significantly associated with bipolar I disorder and with severity of manic and psychotic symptoms in this disorder. Individuals carrying a T allele in the rs28836840 SNP were likely to have a lower risk of bipolar I disorder or lower severity of manic and psychotic symptoms in patients with bipolar I disorder (bipolar I disorder diagnosis: OR = 0.643, 95% Cl = 0.468–0.883, p = 0.006; manic symptoms: β = −2.457, 95% Cl = −4.674 ~ −0.239, p = 0.031; psychotic symptoms: β = −2.501, 95% Cl = −4.700 ~ −0.301, p = 0.027). For the rs2242446 and rs5569 SNPs, there were no significant differences between patients with bipolar I disorder and those without. Our results revealed associations of the rs28386840 SNP with bipolar I disorder diagnosis and with severity of manic and psychotic symptoms. However, the findings reported here require replication in larger samples and various ethnic groups.

Research on the associations between the ratio of second-to-fourth digit lengths (2D:4D ratio) and psychological variables could be a useful method of confirming sex hormone effects on human behavior tendencies. This study investigated the correlations between the 2D:4D ratio and characteristics of temperament and character in an urban community population. We hypothesized that the 2D:4D ratio correlates more strongly with temperament than with character. A total of 728 healthy adults (330 men and 398 women) ranging in age from 20 to 45 years were tested. Subjects completed the Temperament and Character Inventory (TCI) and were examined by measuring the 2D:4D ratio using a direct measurement method. Correlations between the 2D:4D ratio and psychological characteristics were explored. For women only, significant positive correlations with the 2D:4D ratio were found in the TCI-Temperament dimension (TCI-T), particularly in the two subscales of harm avoidance scale. Women with higher 2D:4D ratios had higher fear of uncertainly scores (rpartial = 0.206, p = 0.028) and shyness with strangers scores (rpartial = 0.252, p = 0.024). The 2D:4D ratio shows stronger correlations with temperament than with character. A higher 2D:4D ratio of woman is expected to indicate harm avoidance.

We developed bifacial transparent back contact (TBC) hydrogenated amorphous silicon (a-Si:H) semi-transparent glass-to-glass photovoltaic (PV) modules with emotionally inoffensive and esthetically pleasing colors have been developed by combining the transparent back contact and color of the back glass. Due to the high series resistance of the transparent back contact, the bifacial TBC a-Si:H semi-transparent PV modules had a lower rated power after light soaking than the monofacial opaque (metal) back contact (OBC) a-Si:H semi-transparent PV modules fabricated using the additional laser scribing patterns. However, the TBC a-Si:H semi-transparent PV module produced a higher annual electrical energy output than the OBC a-Si:H semi-transparent PV module thanks to bifacial power generation during the outdoor field test. In particular, the performance ratio of the TBC a-Si:H semi-transparent PV module measured at the optimal tilt angle of 30° surpassed its simulated prediction by a drastically high value of 124.5%. At a higher tilt angle of 85°, bifacial power generation produced a higher deviation between the measured and simulated annual performance of the TBC a-Si:H semi-transparent PV module. Since the reflected albedo has a tendency to increase toward higher tilt angles, bifacial power generation can compensate for the loss of lower direct plane-of-array irradiation at a higher tilt angle. Therefore, the TBC a-Si:H semi-transparent PV module is suitable for the vertically mounted building integrated photovoltaic modules for use in curtain walls, facades, roofs and traffic noise barriers by harvesting reflected and illuminated light.

Vitamin D deficiency has been reported to be associated with various neuropsychiatric disorders. However, there are few studies addressing deficient vitamin D levels and suicidal ideation.Serum vitamin D of 157,211 Korean adult participants were measured using electrochemiluminescence immunoassay. A self-reported questionnaire was used to assess whether participants experienced suicidal ideation. Logistic regression model was used to estimate the odds ratio (OR) of suicidal ideation according to vitamin D levels. The regression was adjusted for a range of covariates.Compared with sufficient vitamin D levels (≥20 ng/mL), deficient vitamin D levels (10 ng/mL) were significantly associated with the risk of suicidal ideation (OR = 1.138, 95% Cl = 1.027-1.262). However, the OR of suicidal ideation was not significantly different between the vitamin D insufficient group (10-19.99 ng/mL) and sufficient group (≥20 ng/mL) (OR = 0.988, 95% Cl = 0.932-1.047).Deficient vitamin D levels were significantly associated with the risk of suicidal ideation. However, the risk of suicidal ideation was not significantly different between the vitamin D insufficient group and sufficient group.

Introduction Shift work is known to have a negative impact on a wide range of health problems such as sleep disturbance, cognitive impairment, and emotional disorders (e.g., anxiety and depression). It is important to understand underlying mechanisms for negative impact of shift work on health problems. This study aimed to investigate psychological and neural mechanisms associated with shift work. Methods Thirty six shift workers (28 females, age = 29.9 ± 7.4) and 35 non-shift workers (20 females, age = 30.5 ± 5.5) participated in this study. They were performing the word Stroop task during fMRI scanning. This task included sleep-related words and negative words to investigate neural substrates associated with sleep-related information and emotional information processing. Neutral words were included as control stimuli. The participants also completed questionnaires assessing sleep-related problems such as Pittsburgh Sleep Quality Index (PSQI) and Epworth Sleepiness Scale, and emotion-related problems such as Beck Depression Inventory and Beck Anxiety Inventory. Two-sample t-tests were conducted to find group differences in self-report measures and neural response to sleep-related words and negative words compared to neutral words. Results Relative to non-shift workers, shift workers showed greater sleep disturbance (i.e., higher PSQI), but they did not show any evidence of emotion-related problems. Shift workers also demonstrated greater neural response to negative words (vs. neutral words) in several prefrontal regions (e.g., dorsal anterior cingulate cortex and dorsolateral prefrontal cortex), anterior insula and caudate compared to non-shift workers. However, shift workers did not show significantly different neural response to sleep-related words (vs. neutral words) compared to non-shift workers. Conclusion The result from this study provides supporting evidence that shift work is associated with subjective sleep disturbance. Shift workers’ heightened neural response to negative information may reflect their increased sensitivity to negative information, that may contribute to sleep disturbance. Support Brain Research Program through the National Research Foundation of Korea funded by the Ministry of Science, ICT & Future Planning (Study No.: 2016M3C7A1904338 and NRF-2018R1D1A1B07049704).

Psychiatric patients with many episodes that do not respond satisfactorily to numerous sequential treatment regimens were included in the treatment resistance studies. Most studies have, however, used a post hoc experimental design that failed to determine the association between biomarkers and the initial risk of treatment-resistant psychiatric disorder (TRP). Such post hoc experimental design can be regarded only as a consequence of having treatment resistance, rather than being a causal risk factor for it. Although informative, data derived from such studies often do not allow for a distinction to be made between cause and effect. To deal with this problem, it is most ideal to enroll untreated patients (those who were diagnosed but have not yet undergone treatment) as study subjects. In this chapter, the authors will review methodological considerations to uncover initial biological risk factors for TRP and propose a better study design for future research by discussing the shortcomings of the traditional study design.

OBJECTIVE We aimed to develop the clinical guideline for headache by the systematic review and synthesis of existing evidence-based guidelines. The purpose of developing the guideline was to improve the appropriateness of diagnosis and treatment of headache disorder, and consequently, to improve patients' pain control and quality of life. The guideline broadly covers the differential diagnosis and treatment of tension-type headache, migraine, cluster headache, and medication-overuse headache. METHODS This is a methodological study based on the ADAPTE methodology, including a systematic review of the literature, quality assessment of the guidelines using the Appraisal of Clinical Guidelines for REsearch & Evaluation II (AGREE II) Instrument, as well as an external review using a Delphi technique. The inclusion criteria for systematic search were as follows: topic-relevant, up-to-date guidelines including evidence from within 5 years, evidence-based guidelines, guidelines written in English or Korean, and guidelines issued by academic institutions or government agencies. RESULTS We selected five guidelines and conducted their quality assessment using the AGREE II Instrument. As a result, one guideline was found to be eligible for adaptation. For 13 key questions, a total of 39 recommendations were proposed with the grading system and revised using the nominal group technique. CONCLUSION Recommendations should be applied to actual clinical sites to achieve the ultimate goal of this guideline; therefore, follow-up activities, such as monitoring of guideline usage and assessment of applicability of the recommendations, should be performed in the future. Further assessment of the effectiveness of the guideline in Korea is needed.

Background : Recent studies on the prospective association between metabolic syndrome (MetS) and depression have reported conflicting findings. Methods : A cohort study was performed with 115,223 middle-aged adults, free of depression at baseline, who underwent at least 2 comprehensive exams between 2012 and 2015. MetS was assessed according to the National Cholesterol Education Program Adult Treatment Panel III. The study endpoint was new onset of depression, defined as a Center for Epidemiologic Studies-Depression Scale score ≥ 16. Results : Over 253,451.6 person-years, 6,833 participants developed depression. When the participants with 0 MetS components were set as a reference, the multivariable-adjusted hazard ratio (HR, 95% confidence interval [CI]) for incident depression formed a U-shaped curve with the number of MetS components (p for trend = 0.229): 1 (1.07 [1.02–1.15]); 2 (0.92 [0.82–1.06]); 3 (0.85 [0.78–1.07]); 4 (1.16 [1.06–1.32]); and 5 MetS components (1.25 [1.10–1.54]). The presence or absence of MetS was not significant in new-onset depression. In examining potential clustering and synergistic effects of the constituent parts, waist circumference was the major driving factor of incident depression, and its relative excess risk due to interaction increased with the number of combinations. Limitations : We used a self-reported depression scale, and the follow-up period was relatively short. Conclusions : Future studies investigating the risk for incident depression should place more focus on the number of MetS abnormalities and specific MetS factors, such as waist circumference, than the presence or absence of MetS.