Background: Korea has witnessed significant fluctuations in its suicide rates in recent decades, which may be related to modifications in its death registration system. This study aimed to explore the structural shifts in suicide trends, as well as accidental and ill-defined deaths in Korea, and to analyze the patterns of these changes. Methods: We analyzed age-adjusted death rates for suicides, deaths due to transport accidents, falls, drowning, fire-related incidents, poisonings, other external causes, and ill-defined deaths in Korea from 1997 to 2021. We identified change-points using the ‘breakpoints’ function from the ‘strucchange’ package and conducted interrupted time series analyses to assess trends before and after these change-points. Results: Korea’s suicide rates had three change-points in February 2003, September 2008, and June 2012, characterized by stair-step changes, with level jumps at the 2003 and 2008 change-points and a sharp decline at the 2012 change-point. Notably, the 2003 and 2008 spikes roughly coincided with modifications to the death ascertainment process. The trend in suicide rates showed a downward slope within the 2003–2008 and 2008–2012 periods.Furthermore, ill-defined deaths and most accidental deaths decreased rapidly through several change-points in the early and mid-2000s. Conclusion The marked fluctuations in Korea’s suicide rate during the 2000s may be largely attributed to improvements in suicide classification, with potential implications beyond socio-economic factors. These findings suggest that the actual prevalence of suicides in Korea in the 2000s might have been considerably higher than officially reported.

Objective: Increased fast food consumption can have adverse effects on health and well-being among adolescents, posing a significant public health concern. The school closures due to the coronavirus disease-2019 (COVID-19) pandemic have led to changes in eating patterns and disrupted a balance diet among adolescents. This study explored the factors associated with fast food consumption among adolescents during school closures due to the COVID-19 pandemic. Methods: A total of 1,710 middle and high school students in Gwangju, South Korea participated in a cross-sectional survey. The self-administered questionnaire included items assessing dietary intake, physical activity, sleep, media use, and sociodemographic information. The Patient Health Questonnaire-9, Generalized Anxiety Disorder-7, and three item version of the UCLA Loneliness Scale were also administered. Multivariable logistic regression was used to examine the factors associated with increased fast food consumption. Results: Approximately 34.6% of the surveyed adolescents reported increased fast food consumption during school closures, as well as increased sleep duration, increased sedentary behaviors including watching TV and using the internet, and reduced physical activity. Multivariable logistic regression analysis revealed that fast food consumption during school closures was associated with irregular patterns of main meals and sleep, decreased physical activity, increased internet use, and a lack of daytime adult supervision. Conclusion Our results highlight the need for dietary and lifestyle monitoring and guidelines to promote health among adolescents, especially during school closures. In conclusion, nutrition intervention programs aiming to limit fast food consumption and enhance healthy dietary habits among adolescents during long-term school closures are warranted.

Objective: To investigate the effects of dietary habits on general and abdominal obesity in community-dwelling patients with schizophrenia spectrum disorder according to sex. Methods: A total of 270 patients with schizophrenia spectrum disorder registered at mental health welfare centers and rehabilitation facilities were recruited. General obesity was defined as a body mass index ≥ 30 kg/m 2 , and abdominal obesity was defined as a waist circumstance ≥ 90 cm in men and ≥ 85 cm in women. Dietary habits were evaluated using dietary guidelines published by the Korean Ministry of Health and Welfare. Demographic and clinical characteristics along with dietary habits and information related to obesity were collected. Factors related to obesity were evaluated separately by sex. Results: Dietary habits differed according to sex, in that scores for healthy eating habits were lower in men than in women. In men, the prevalences of general and abdominal obesity were 17.0% and 37.3%, respectively. In women, the prevalences of general and abdominal obesity were 23.1% and 38.5%, respectively. Regression analysis showed that the scores of regular eating habits were negatively associated with general and abdominal obesity in men, and the scores of healthy eating habits were negatively associated with general and abdominal obesity in women. Conclusion Among patients with schizophrenia, regular eating habits might reduce the risk of obesity in men, and healthy eating habits might reduce the risk of obesity in women. Nutrition education should be provided to community-dwelling patients with schizophrenia to prevent obesity in this population.

Background: This study characterized coronavirus disease 2019 (COVID-19) vaccination behavior in the Korean general population using cluster analysis and explored related psychological factors. Methods: We categorized 1,500 individuals based on their attitudes toward COVID-19 vaccination using hierarchical clustering and identified their level of vaccine acceptance. We examined the associations between vaccine acceptance and behavioral and psychological characteristics. Results: Clustering revealed three groups according to vaccine acceptance: ‘totally accepting’ (n = 354, 23.6%), ‘somewhat accepting’ (n = 523, 34.9%), and ‘reluctant’ (n = 623, 41.5%). Approximately 60% of all participants who belonged to the ‘totally accepting’ and ‘somewhat accepting’ groups were willing to receive a COVID-19 vaccine despite concerns about its side effects. High vaccine acceptance was associated with older age, regular influenza vaccination, and trust in formal sources of information. Participants with high vaccine acceptance had higher levels of gratitude, extraversion, agreeableness, and conscientiousness, and lower levels of depression, anxiety, and neuroticism. Conclusions People weighed the benefits of COVID-19 vaccination against the risk of side effects when deciding to receive the COVID-19 vaccine. Our findings also indicate that this vaccination behavior may be affected by coping mechanisms and psychological factors.

Objectives: This study examined the associations between Internet addiction and suicide and non-suicidal self-injury (NSSI) among South Korean adolescents. Methods: We conducted a cross-sectional study of 1694 Korean adolescents. The suicidal Ideation Questionnaire and Deliberate SelfHarm Inventories were used to identify high-risk suicide and NSSI groups, respectively. Internet addiction was assessed using the Internet Addiction Scale. Other questionnaires included sociodemographic data, perceived academic stress, and daily life-related factors. We also performed a logistic regression analysis using the high suicide risk and NSSI groups as dependent variables. Results: The high suicide risk and NSSI prevalence rates among participants were 11.8% and 28.3%, respectively. A multivariable logistic regression analysis revealed that Internet addiction is associated with higher suicide risk and NSSI. Additionally, being female and academic stress were significant suicide risk factors, while male participants had a higher NSSI prevalence. Conclusion Our results suggest that monitoring adolescents’ Internet use and providing education to prevent Internet addiction would lower high suicide and NSSI risk. Moreover, suicide and NSSI risk screening in adolescents with Internet addiction and providing suitable interventions will be essential for the preventing suicide and NSSI.

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.

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.

As the need for a nationwide organ-transplant registry emerged, a prospective registry, the Korean Organ Transplantation Registry (KOTRY), was initiated in 2014. Here, we present baseline characteristics and outcomes of the kidney-transplant cohort for 2014 through 2019. Methods: The KOTRY consists of five organ-transplant cohorts (kidney, liver, lung, heart, and pancreas). Data and samples were prospectively collected from transplant recipients and donors at baseline and follow-up visits; and epidemiological trends, allograft outcomes, and patient outcomes, such as posttransplant complications, comorbidities, and mortality, were analyzed. Results: From 2014 to 2019, there were a total of 6,129 registered kidney transplants (64.8% with living donors and 35.2% with deceased donors) with a mean recipient age of 49.4 ± 11.5 years, and 59.7% were male. ABO-incompatible transplants totaled 17.4% of all transplants, and 15.0% of transplants were preemptive. The overall 1- and 5-year patient survival rates were 98.4% and 95.8%, respectively, and the 1- and 5-year graft survival rates were 97.1% and 90.5%, respectively. During a mean follow-up of 3.8 years, biopsy-proven acute rejection episodes occurred in 17.0% of cases. The mean age of donors was 47.3 ± 12.9 years, and 52.6% were male. Among living donors, the largest category of donors was spouses, while, among deceased donors, 31.2% were expanded-criteria donors. The mean serum creatinine concentrations of living donors were 0.78 ± 0.62 mg/dL and 1.09 ± 0.24 mg/dL at baseline and 1 year after kidney transplantation, respectively. Conclusion: The KOTRY, a systematic Korean transplant cohort, can serve as a valuable epidemiological database of Korean kidney transplants.

Objective: This study was performed to identify factors associated with depression and anxiety among Korean adolescents during the coronavirus disease (COVID-19) pandemic. Methods: We conducted a cross-sectional study of 1,898 Korean adolescents (55.2% male, 44.8% female) ranging in age from 12 to 17 years (mean±standard deviaion age, 15.4±2.6 years). Depression and anxiety were defined as a Patient Health Questionnaire-9 score ≥10 and Generalized Anxiety Disorder-7 score ≥10, respectively. Other questionnaires included sociodemographic data, psychosocial stresses, and experiences in association with COVID-19. Psychiatric scales included Gratitude Questionnaire-6, Perceived Stress Scale-10, and UCLA Loneliness Scale-3. Results: The prevalence rates of depressive and anxiety symptoms among participants were 13.8% and 21.0%, respectively. Multivariable logistic regression analysis revealed that female sex, fear of COVID-19 infection, low gratitude were risk factors for depression. Fear of COVID-19 infection, increased TV watching time, and academic-related stress were risk factors for anxiety. Conclusion Depression and anxiety were prevalent during the pandemic in Korean adolescents, and were associated with fear of COVID-19 infection. Providing appropriate information on COVID-19, helping adolescents manage academic-related stress and maintain daily life patterns, and implementing interventions to foster gratitude are important for preventing depression and anxiety in Korean adolescents.

Objective: The aim of the study was to develop a checklist for mental health clinicians to predict and manage suicidality. Methods: A literature review of the risk and protective factors for suicide was conducted to develop a checklist for evaluating suicidality. Results: The fixed risk factors included sex (male), age (older individuals), history of childhood adversity, and a family history of suicide. Changeable risk factors included marital status (single), economic status (poverty), physical illness, history of psychiatric hospitalization, and history of suicide attempts. Recent discharge from a mental hospital and a recent history of suicide attempts were also included. Manageable risk factors included depression (history and current), alcohol problems (frequent drinking and alcohol abuse), hopelessness, agitation, impulsivity, impaired reality testing, and command hallucinations. Protective factors included responsibility to family, social support, moral objections to suicide, religiosity, motivation to get treatment, ability to cope with stress, and a healthy lifestyle. A final score was assigned based on the sum of the risk and protective factor scores. Conclusion We believe that the development of this checklist will help mental health clinicians to better assess those at risk for suicidal behavior. Further studies are necessary to validate the checklist.