Background: Caffeine, a widely consumed stimulant, affects sleep and mental health. Shift work disrupts the circadian rhythm and has been associated with various mental health issues, such as depression, anxiety, and suicidal ideation. Objective: This study explored the associations between caffeine consumption, sleep duration, and mental health outcomes, particularly suicidal ideation, among shift workers in Korea. Methods: Data from the 6th Korea National Health and Nutrition Examination Survey (2013, 2015), which comprised 4723 adults aged 19 and older, were analyzed. Participants were categorized into groups based on average daily coffee consumption and work patterns. Multiple logistic regression analyses were conducted to determine the impact of caffeine consumption and work patterns on mental health outcomes. Results: Participants worked longer hours, reported higher perceived stress levels, and slightly decreased sleep duration as daily coffee consumption increased. However, no significant differences were observed in depression or suicidal ideation across the coffee consumption groups. Logistic regression analysis indicated a trend towards higher suicidal ideation risk with increased coffee intake, particularly among those who consumed three or more cups per day (OR 5.67, 95% CI 1.82–17.59). Conclusion: This study suggests a complex relationship between caffeine consumption, work patterns, and mental health outcomes. Although caffeine intake is associated with increased work hours and stress, its impact on suicidal ideation is influenced by occupational factors.

Hypovitaminosis D and stress are common problems among the elderly. The aim of this cross-sectional nationally representative study was to evaluate the association between hypovitaminosis D and stress perception using large-scale nationally representative data from the Korea National Health and Nutrition Examination Survey (2012–2013). In our study, a total of 1393 elders (≥65 years old) were included to evaluate the association between hypovitaminosis D and stress perception. Serum 25-hydroxyvitamin D levels were determined using radioimmunoassay, and perceived stress status was assessed by a self-reporting questionnaire. The association between hypovitaminosis D and stress perception according to sex was examined using logistic regression analysis. After multivariate adjustment for sociodemographic and lifestyle factors and comorbidities, hypovitaminosis D was significantly associated with perceived stress (odds ratio, 2.73; 95% confidence interval, 1.10–6.77; p = 0.029) among women; however, this association was not significant among men. Hypovitaminosis D was a risk factor for higher stress perception in older Korean women. Even though the role of vitamin D in stress perception is still unclear, we suggest screening for hypovitaminosis D among the elderly.

This study investigates the effects of a new medical insurance payment system for hospice patients in palliative care programs and analyzes length of survival (LoS) determinants. At the Pusan National University Hospital hospice center, between January 2015 and April 2016, 276 patients were hospitalized with several diagnosed types of terminal stage cancer. This study separated patients into two groups, “old” and “new,” by admission date, considering the new system has been applied from July 15, 2015. The study subsequently compared LoS, total cost, and out-of-pocket expenses for the two groups. Overall, 142 patients applied to the new medical insurance payment system group, while the old medical insurance payment system included 134 patients. The results do not show a significantly negative difference in LoS for the new system group (p = 0.054). Total cost is higher within the new group (p < 0.001); however, the new system registers lower patient out-of-pocket expenses (p < 0.001). The novelty of this study is proving that the new medical insurance payment system is not inferior to the classic one in terms of LoS. The total cost of the new system increased due to a multidisciplinary approach toward palliative care. However, out-of-pocket expenses for patients overall decreased, easing their financial burden.

Background/Objectives. Type 2 diabetes mellitus (T2DM) has been linked to an increased risk of several cancers. However, the influence of metformin and dipeptidyl peptidase-4 inhibitors (DPP4is) on the risk of cancers remains unclear. We investigated the association between using DPP4is and/or metformin and cancer risk compared with other glucose-lowering drugs (GLDs). Methods. This retrospective multicenter cohort study was performed using 11 hospital databases standardized to the OMOP Common Data Model (CDM) within the Observational Health Data Sciences and Informatics (OHDSI) network. T2DM patients using only DPP4is and/or metformin (DPP4is/Met group) were compared with those using other GLDs (other GLD group). From 413,344 eligible patients, propensity score (PS) 1:1 matching yielded 6674 patients in each group. Cox proportional hazards models were used to analyze cancer risk, and a random-effects meta-analysis was performed to calculate hazard ratios (HRs). Results. The DPP4is/Met group exhibited a significantly lower risk of incident cancer than the other GLD group (HR, 0.54; 95% CI, 0.41–0.69). This association was consistent across all hospitals. Regarding cancer-specific distributions, the DPP4is/Met group showed lower proportions of breast and prostate cancers, whereas the other GLD group showed higher proportions of lower gastrointestinal cancers. Conclusions. In this large multicenter study, using DPP4is and metformin showed a substantial association with a lower risk of cancer in T2DM patients relative to other GLDs. These findings suggest a potential protective effect of metformin and support the neutral-to-beneficial effect on cancer of DPP4is.

Background: Sarcopenic obesity, defined as the coexistence of low muscle mass and excess adiposity, is an emerging public health concern in aging populations. However, longitudinal evidence on the association between socioeconomic status (SES) and incident sarcopenic obesity remains limited, particularly in Asian populations. This study aimed to investigate the association between SES and the long-term incidence of sarcopenic obesity in a large Korean cohort. Methods: We conducted a prospective cohort study using data from the Korean Genome and Epidemiology Study (KoGES). Community-dwelling adults aged ≥ 40 years without sarcopenic obesity at baseline were followed for a mean of 17 years. Sarcopenic obesity was defined as low body mass index (BMI)-adjusted skeletal muscle mass (sex-specific lowest 20th percentile) combined with obesity (BMI ≥ 25 kg/m²). SES indicators included educational attainment, household income, and marital status. Kaplan–Meier methods were used to estimate cumulative incidence, and Cox proportional hazards models were applied to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) with sequential adjustment for demographic, lifestyle, and metabolic factors. Results: In the fully adjusted model, participants with elementary school education showed a higher hazard ratio of incident sarcopenic obesity compared with those with college education or higher (HR 1.39; 95% CI 1.11–1.73; p = 0.003). Similarly, individuals with a household income < 1.0 million KRW per month had a higher hazard ratio compared with those earning ≥4.0 million KRW (HR 1.31; 95% CI 1.02–1.70; p = 0.037). Unmarried participants also showed a higher hazard ratio compared with married individuals (HR 1.31; 95% CI 1.09–1.57; p = 0.003). Conclusions: Lower SES was independently associated with a higher incidence of sarcopenic obesity over long-term follow-up in this population-based cohort. These findings highlight the importance of considering socioeconomic factors in the prevention of sarcopenic obesity.