Purpose: Bronchiolitis obliterans syndrome (BOS) can develop as a manifestation of graft-versus-host disease following allogeneic hematopoietic stem cell transplantation (allo-HSCT), and may ultimately require lung transplantation (LT). However, reports on LT outcomes for BOS after allo-HSCT are limited. This study aimed to compare the outcomes of LT for BOS following allo-HSCT with those for idiopathic pulmonary fibrosis (IPF). Materials and Methods: A total of 487 patients underwent LT between January 2010 and August 2023. Among them, the baseline characteristics and outcomes of 35 patients with BOS following allo-HSCT and 216 patients with IPF were analyzed. Results: The BOS group was younger and had a lower body mass index (BMI) compared to the IPF group (33.7±11.9 years vs.59.7±7.3 years, p<0.001; 17.6±3.7 kg/m2 vs. 22.0±3.6 kg/m2 , p<0.001, respectively). The proportion of male patients was lower in the BOS group than in the IPF group (54.3% vs. 84.3%, p<0.001). Preoperative ventilator support was more common in the BOS group compared to the IPF group (62.9% vs. 32.4%, p=0.001). In Kaplan–Meier survival analysis, the 5-year survival rate was significantly higher in the BOS group than in the IPF group (71.0% vs. 44.9%, p=0.022). In the Cox proportional hazards model, age was the only factor significantly associated with survival [hazard ratio (95% confidence interval): 1.04 (1.02–1.07), p<0.001]. Conclusion The survival rate of the BOS group was not inferior to that of the IPF group after adjusting for sex, age, and BMI. Therefore, LT should be actively considered as a treatment option for patients with BOS following allo-HSCT.

Objective: To investigate the longitudinal association between sarcopenia and depressive symptoms in community-dwellingolder adults, focusing on sex-specific differences. Methods: This 2-year prospective study utilized data from the Korean Frailty and Aging Cohort Study. We included 1,366participants (700 men, 666 women) aged 70-84 years who were free of depressive symptoms (Short Geriatric Depression Scale-Korean [SGDS-K]<8) at baseline. Sarcopenia status (no sarcopenia, sarcopenia, severe sarcopenia) was defined by the AsianWorking Group for Sarcopenia 2019 criteria. Multivariate logistic regression analysis was performed to assess the association be-tween baseline sarcopenia and incident depressive symptoms (SGDS-K≥8) at follow-up, adjusting for covariates. Results: After adjustment, baseline severe sarcopenia was significantly associated with a higher risk of incident depression (adjusted odds ratio [aOR]=3.040, 95% confidence interval [CI]=1.494-6.188). In the sex-stratified analysis, this association remained robust only in men (aOR=3.344, 95% CI=1.332-8.395), but was not statistically significant in women (aOR=2.490, 95% CI=0.699-8.872, p=0.159). Conclusion Severe sarcopenia independently predicts for 2-year development of depressive symptoms, particularly amongolder Korean men. These findings highlight a significant sex difference in the temporal relationship between sarcopenia and de-pression for older men.

Objective: Research specifically targeting suicidal ideation (SI) in middle-aged populations remains limited. This study aimed to predict future and concurrent SI in middle-aged Korean adults by applying four machine learning (ML) models to a nationally representative longitudinal dataset. Methods: We analyzed data from 8,992 individuals aged 40–64 years who participated in the Korea Welfare Panel Study from the 7th (2011) to the 18th (2022) waves. Four ML algorithms were employed to develop the predictive models. The SHapley Additive exPlanations method was applied to enhance explainability. Results: Approximately half of the participants’ mean age was 49.3±8.2 years (range, 40–64 years) and 52.2% were male. The average annual SI rate between 2011 and 2022 was 2.8%±1.2%. Predictive performance for future SI was satisfactory, with area under the receiver operating characteristic curve (AUC) values of up to 0.806 (logistic regression, LR). Predictions for concurrent SI demonstrated AUC values of up to 0.907 (LR). Key predictors of future SI included subjective health status, satisfaction with family and spousal relationships, housing environment, and educational attainment. Concurrent SI was strongly associated with immediate stressors such as family violence and income dissatisfaction. Conclusion The ML models demonstrated good-to-excellent predictive performance for SI. These findings emphasize the importance of health, family, and socioeconomic factors, alongside mental health indicators in the prevention of SI among middle-aged adults. Building on these findings, tailored intervention strategies that comprehensively address multidimensional risk factors are essential for effective SI prevention.

Objectives: ：Among the various risk factors for suicide, geographic factors have different effects on males and females. This study aimed to identify differences between genders in spatiotemporal dependence and spatiotemporal patterns of suicide mortality over the preceding decade. Methods: ：This research analyzed the age-adjusted suicide mortality rate per 100,000 population, spanning from 2012 to 2021, for intentional suicides across each administrative district (229 Si, Gun, Gu) in Korea. Data were sourced from the National Statistical Office of the Korean Statistical Information Service. The Moran’s I in-dex for spatial autocorrelation of the suicide mortality rates was computed. An emerging hot spot analysis was conducted to examine the community-level spatiotemporal distribution patterns, thus providing insight into the re-gional clustering characteristics that reflect the temporal-spatial clusters of suicide mortality rates. Results: ：TIn males, the Moran’s I indices were almost above 0 (p-value<0.05) for most years, indicating sig-nificant spatial autocorrelation. Conversely, no significant regional clustering was observed among females dur-ing the same period. The emerging hot spot analysis, focusing on the temporal trends in the spatial distributionof male suicide mortality rates from 2012 to 2021, identified two distinct time series patterns and a total of 12 hot spot areas: seven new spots and five sporadic spots. Conclusions ：This study is the first to intuitively demonstrate the disparities in spatiotemporal dependencies and patterns of suicide mortality rates in Korea between genders. The findings highlight the necessity for tailoredsuicide prevention strategies that are sensitive to gender differences.

Objectives: Eveningness predominates in adolescence. Morningness has been reported to be associated with mental toughness via resilience. Morningness could be related to healthy sleep habits and a good personality. Methods: Sleep-related behaviors, such as weekend oversleep, social jetlag, and daytime sunlight exposure between 10:00 and 15:00, were evaluated using sleep-related questionnaires. Morningness-eveningness questionnaire, insomnia severity index, Epworth sleepiness scale, hospital anxiety and depression scale and defense style questionnaire were used. This study includes 1,610 high school students. Results: Multiple linear regression analysis revealed that morningness is predicted by male sex (β=0.115, t=4.769, p<0.001) and greater adaptive (β=0.092, t=3.506, p<0.001) and self-suppressive defense styles (β=0.072, t=2.192, p=0.029) and lesser immature defense styles (β=-0.163, t=-4.782, p<0.001) after controlling for age, sleep quality, depression, anxiety. Morningness is also predicted by greater sublimation (β=0.09, t=3.541, p<0.001) and reaction formation (β=0.112, t=4.488, p<0.001) and lesser consumption (β=-0.062, t=-2.501, p=0.012), passive aggression (β=-0.101, t=-3.747, p<0.001) and withdrawal (β=-0.084, t=-2.955, p=0.003), and male sex (β=0.117, t=4.896, p<0.001) after controlling for age, sleep quality, depression, and anxiety. Conclusion Morniness in adolescence may be related to a positive personality. Promoting morningness might be related to healthy development in personality.

Objectives: ：Among the various risk factors for suicide, geographic factors have different effects on males and females. This study aimed to identify differences between genders in spatiotemporal dependence and spatiotemporal patterns of suicide mortality over the preceding decade. Methods: ：This research analyzed the age-adjusted suicide mortality rate per 100,000 population, spanning from 2012 to 2021, for intentional suicides across each administrative district (229 Si, Gun, Gu) in Korea. Data were sourced from the National Statistical Office of the Korean Statistical Information Service. The Moran’s I in-dex for spatial autocorrelation of the suicide mortality rates was computed. An emerging hot spot analysis was conducted to examine the community-level spatiotemporal distribution patterns, thus providing insight into the re-gional clustering characteristics that reflect the temporal-spatial clusters of suicide mortality rates. Results: ：TIn males, the Moran’s I indices were almost above 0 (p-value<0.05) for most years, indicating sig-nificant spatial autocorrelation. Conversely, no significant regional clustering was observed among females dur-ing the same period. The emerging hot spot analysis, focusing on the temporal trends in the spatial distributionof male suicide mortality rates from 2012 to 2021, identified two distinct time series patterns and a total of 12 hot spot areas: seven new spots and five sporadic spots. Conclusions ：This study is the first to intuitively demonstrate the disparities in spatiotemporal dependencies and patterns of suicide mortality rates in Korea between genders. The findings highlight the necessity for tailoredsuicide prevention strategies that are sensitive to gender differences.

Objectives: Eveningness predominates in adolescence. Morningness has been reported to be associated with mental toughness via resilience. Morningness could be related to healthy sleep habits and a good personality. Methods: Sleep-related behaviors, such as weekend oversleep, social jetlag, and daytime sunlight exposure between 10:00 and 15:00, were evaluated using sleep-related questionnaires. Morningness-eveningness questionnaire, insomnia severity index, Epworth sleepiness scale, hospital anxiety and depression scale and defense style questionnaire were used. This study includes 1,610 high school students. Results: Multiple linear regression analysis revealed that morningness is predicted by male sex (β=0.115, t=4.769, p<0.001) and greater adaptive (β=0.092, t=3.506, p<0.001) and self-suppressive defense styles (β=0.072, t=2.192, p=0.029) and lesser immature defense styles (β=-0.163, t=-4.782, p<0.001) after controlling for age, sleep quality, depression, anxiety. Morningness is also predicted by greater sublimation (β=0.09, t=3.541, p<0.001) and reaction formation (β=0.112, t=4.488, p<0.001) and lesser consumption (β=-0.062, t=-2.501, p=0.012), passive aggression (β=-0.101, t=-3.747, p<0.001) and withdrawal (β=-0.084, t=-2.955, p=0.003), and male sex (β=0.117, t=4.896, p<0.001) after controlling for age, sleep quality, depression, and anxiety. Conclusion Morniness in adolescence may be related to a positive personality. Promoting morningness might be related to healthy development in personality.

Objectives: ：Among the various risk factors for suicide, geographic factors have different effects on males and females. This study aimed to identify differences between genders in spatiotemporal dependence and spatiotemporal patterns of suicide mortality over the preceding decade. Methods: ：This research analyzed the age-adjusted suicide mortality rate per 100,000 population, spanning from 2012 to 2021, for intentional suicides across each administrative district (229 Si, Gun, Gu) in Korea. Data were sourced from the National Statistical Office of the Korean Statistical Information Service. The Moran’s I in-dex for spatial autocorrelation of the suicide mortality rates was computed. An emerging hot spot analysis was conducted to examine the community-level spatiotemporal distribution patterns, thus providing insight into the re-gional clustering characteristics that reflect the temporal-spatial clusters of suicide mortality rates. Results: ：TIn males, the Moran’s I indices were almost above 0 (p-value<0.05) for most years, indicating sig-nificant spatial autocorrelation. Conversely, no significant regional clustering was observed among females dur-ing the same period. The emerging hot spot analysis, focusing on the temporal trends in the spatial distributionof male suicide mortality rates from 2012 to 2021, identified two distinct time series patterns and a total of 12 hot spot areas: seven new spots and five sporadic spots. Conclusions ：This study is the first to intuitively demonstrate the disparities in spatiotemporal dependencies and patterns of suicide mortality rates in Korea between genders. The findings highlight the necessity for tailoredsuicide prevention strategies that are sensitive to gender differences.

OBJECTIVES: The relationship of depressive symptoms to lower extremity function and balance, especially in older adults without a depression diagnosis, remains unclear. Therefore, our study analyzed this relationship using a large sample of Korean older adults. METHODS: We used data from the Korean National Health Insurance Service’s Health Screening Program database. Individuals aged 66 years who had undergone the National Screening Program for Transitional Ages in Korea and were without a diagnosis of depressive disorder were included. The lower extremity function and balance were evaluated using 2 physical tests, while depressive symptoms were assessed using a 3-question survey. Multivariable-adjusted logistic regression analysis was used to examine the association between depressive symptoms and lower extremity function and balance. RESULTS: Among 66,041 individuals, those with depressive symptoms showed significantly higher rates of abnormal lower extremity function and abnormal balance. The adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for the association of depressive symptoms to abnormal lower extremity function and abnormal balance were (aOR, 1.34; 95% CI, 1.25 to 1.44) and (aOR, 1.38; 95% CI, 1.29 to 1.48), respectively. Assessment of the relationship based on depressive symptom scores revealed that higher scores were associated with higher aORs (p for trend <0.001). Subgroup analyses further confirmed this relationship, especially among patients with cerebrovascular disease or dementia. CONCLUSIONS This study revealed an association between depressive symptoms and the abnormal lower extremity function and balance of 66-year-old individuals without a diagnosis of depressive disorder.

Background: A decline in masticatory function may indicate brain dysfunction related to dementia, but the relationship between masticatory function and dementia risk remains unclear. This study aimed to investigate whether masticatory function is associated with the risk of cognitive decline and dementia. Methods: Data were obtained from the nationwide prospective cohort study of randomly sampled community-dwelling Koreans aged ≥ 60 years. The 5,064 non-demented participants, whose number of chewing cycles per bite was assessed by clinical interview, were followed for 8 years with biennial assessments of cognitive performance and clinical diagnoses of all-cause dementia and Alzheimer’s disease (AD). Structural brain magnetic resonance imaging was collected from a subset of cohort participants and their spouses for imaging analyses. Results: Males who chewed ≥ 30 cycles/bite had faster decline in global cognition and memory function and were at higher risk for incident all-cause dementia (hazard ratio [HR], 2.91; 95% confidence interval [CI], 1.18–7.18) and AD (HR, 3.22; 95% CI, 1.14–9.11) compared to males with less than 10 cycles/bite. Additionally, increased chewing cycles in males were associated with reduced brain volume, particularly in regions involved in compensatory cognitive control of mastication. There was no significant association between chewing cycles and the risk of dementia or brain volume in females. Conclusion Older men who frequently chew their meals could be considered a notable population at risk for dementia who should be carefully assessed for their cognitive trajectories.