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.

Purpose: Among the characteristics of non-alcoholic fatty liver disease (NAFLD), hepatic steatosis is due to excessive fat accumulation and causes liver damage and lipotoxicity, which are associated with insulin resistance, endoplasmic reticulum (ER) stress, and apoptosis. Umbelliferone (UMB) has various powerful pharmacological properties, such as antioxidant, anti-hyperglycemic, anti-viral, and anti-inflammatory effects. However, the mechanism of action in hepatic steatosis and lipid-induced ER stress is still unclear. Thus, the efficacy of UMB in hepatic steatosis and palmitate (PA)-induced hepatocellular lipotoxicity was evaluated in the present study. Materials and Methods: Male C57BL/6J mice (n=40) were divided into four groups: regular diet (RD), UMB-supplemented RD, high-fat diet (HFD), and UMB-supplemented HFD. All mice were fed orally for 12 weeks. In addition, the effects of UMB on lipotoxicity were investigated in AML12 cells treated with PA (250 μM) for 24 h; Western blot analysis was used to evaluate the changes in ER stress and apoptotic-associated proteins. Results: Administration with UMB in HFD-fed mice reduced lipid accumulation and hepatic triglyceride (TG) as well as serum insulin and glucose levels. In AML12 cells, UMB treatment reduced lipid accumulation as indicated by decreases in the levels of lipogenesis markers, such as SREBP1, FAS, PPAR-γ, and ADRP. Furthermore, UMB reduced both oxidative stress and ER stress-related cellular apoptosis. Conclusion UMB supplementation ameliorated hepatic steatosis and improved insulin resistance by inhibiting lipid accumulation and regulating ER stress. These findings strongly suggest that UMB may be a potential therapeutic compound against NAFLD.

Background/Aims: We evaluated the feasibility and long-term efficacy of the combination of cytarabine, idarubicin, and all-trans retinoic acid (ATRA) for treating patients with newly diagnosed acute promyelocytic leukemia (APL). Methods: We included 87 patients with newly diagnosed acute myeloid leukemia and a t(15;17) or promyelocytic leukemia/retinoic acid receptor alpha (PML-RARα) mutation. Patients received 12 mg/m2/day idarubicin intravenously for 3 days and 100 mg/m2/day cytarabine for 7 days, plus 45 mg/m2/day ATRA. Clinical outcomes included complete remission (CR), relapse-free survival (RFS), overall survival (OS), and the secondary malignancy incidence during a 20-year follow-up. Results: The CR, 10-year RFS, and 10-year OS rates were 89.7%, 94.1%, and 73.8%, respectively, for all patients. The 10-year OS rate was 100% for patients that achieved CR. Subjects were classified according to the white blood cell (WBC) count in peripheral blood at diagnosis (low-risk, WBC < 10,000/mm3; high-risk, WBC ≥ 10,000/mm3). The low-risk group had significantly higher RFS and OS rates than the high-risk group, but the outcomes were not superior to the current standard treatment (arsenic trioxide plus ATRA). Toxicities were similar to those observed with anthracycline plus ATRA, and higher than those observed with arsenic trioxide plus ATRA. The secondary malignancy incidence after APL treatment was 2.7%, among the 75 patients that achieved CR, and 5.0% among the 40 patients that survived more than 5 years after the APL diagnosis. Conclusions Adding cytarabine to anthracycline plus ATRA was not inferior to anthracycline plus ATRA alone, but it was not comparable to arsenic trioxide plus ATRA. The probability of secondary malignancy was low.

Genome-wide association studies (GWASs) facilitated the discovery of countless disease-associated variants. However, GWASs have mostly been conducted in European ancestry samples. Recent studies have reported that these European-based association results may reduce disease prediction accuracy when applied in non-Europeans. Therefore, previously reported variants should be validated in non-European populations to establish reliable scientific evidence for precision medicine. In this study, we validated known associations with type 2 diabetes (T2D) and related metabolic traits in 125,850 samples from a Korean population genotyped by the Korea Biobank Array (KBA). At the end of December 2020, there were 8,823 variants associated with glycemic traits, lipids, liver enzymes, and T2D in the GWAS catalog. Considering the availability of imputed datasets in the KBA genome data, publicly available East-Asian T2D summary statistics, and the linkage disequilibrium among the variants (r2 < 0.2), 2,900 independent variants were selected for further analysis. Among these, 1,837 variants (63.3%) were statistically significant (p < 0.05). Most of the non-replicated variants (n = 1,063) showed insufficient statistical power and decreased minor allele frequencies compared with the replicated variants. Moreover, known variants showed <10% genetic heritability. These results could provide valuable scientific evidence for future study designs, the current power of GWASs, and future applications in precision medicine in the Korean population.

PURPOSE: Women with dense breast are known to be at high risk for breast cancer, but their prevalence and number of Korean women are unknown. The current study was to investigate the distribution of mammographic breast density by age of women undergoing screening mammography, and to estimate the prevalence of Korean women with dense breasts, quantitatively. MATERIALS AND METHODS: For obtaining a nationwide representative sample, 6,481 mammograms were collected from 86 screening units participated in the National Cancer Screening Program for breast cancer. Based on the American College of Radiology Breast Imaging Reporting and Data System classification, breast density was evaluated by six breast radiologists, qualitatively. We applied these breast density distributions to age-specific counts of the Korean women population derived to mid-year 2017 to estimate the number of Korean women with dense breasts. RESULTS: Overall, 54.4% (95% confidence interval [CI], 52.9% to 55.8%) of women 40 to 69 years of age had heterogeneously or extremely dense breasts, and this proportion was inversely associated with age. Based on the age distribution of Korean women, we estimated that 6,083,000 women (95% CI, 5,919,600 to 6,245,600) age 40-69 years in Korean have dense breasts. Women aged 40-49 years (n=3,450,000) accounted for 56.7% of this group. CONCLUSION: More than half of Korean women aged 40 and over have dense breasts. To prevent breast cancer effectively and efficiently, it is necessary to develop a new personalized prevention strategy considering her status of breast density.
Age Distribution ; Breast Neoplasms ; Breast ; Classification ; Cross-Sectional Studies ; Early Detection of Cancer ; Female ; Humans ; Information Systems ; Korea ; Mammography ; Mass Screening ; Prevalence

Over the last decade, genome-wide association studies (GWASs) have provided an unprecedented amount of genetic variations that are associated with various phenotypes. However, previous GWAS were mostly conducted in European populations, and these biased results for non-Europeans may result in a significant reduction in risk prediction for non-Europeans. An issue with the early GWAS was the winner's curse problem, which led to misleading results when constructing the polygenic risk scores (PRS). Therefore, more non-European population-based studies are needed to validate reported variants and improve genetic risk assessment across diverse populations. In this study, we validated 422 variants independently associated with glycemic indexes, liver enzymes, and type 2 diabetes in 125,872 samples from a Korean population, and further validated the results by assessing publicly available summary statistics from European GWAS (n = 898,130). Among the 422 independently associated variants, 284, 320, and 361 variants were replicated in Koreans, Europeans, and either one of the two populations. In addition, the effect sizes for Koreans and Europeans were moderately correlated (r = 0.33–0.68). However, 61 variants were not replicated in both Koreans and Europeans. Our findings provide valuable information on effect sizes and statistical significance, which is essential to improve the assessment of disease risk using PRS analysis.
Asian Continental Ancestry Group ; Bias (Epidemiology) ; Genetic Variation ; Genome-Wide Association Study ; Glycemic Index ; Humans ; Liver ; Phenotype ; Polymorphism, Single Nucleotide ; Risk Assessment

Over the last decade, genome-wide association studies (GWASs) have provided an unprecedented amount of genetic variations that are associated with various phenotypes. However, previous GWAS were mostly conducted in European populations, and these biased results for non-Europeans may result in a significant reduction in risk prediction for non-Europeans. An issue with the early GWAS was the winner's curse problem, which led to misleading results when constructing the polygenic risk scores (PRS). Therefore, more non-European population-based studies are needed to validate reported variants and improve genetic risk assessment across diverse populations. In this study, we validated 422 variants independently associated with glycemic indexes, liver enzymes, and type 2 diabetes in 125,872 samples from a Korean population, and further validated the results by assessing publicly available summary statistics from European GWAS (n = 898,130). Among the 422 independently associated variants, 284, 320, and 361 variants were replicated in Koreans, Europeans, and either one of the two populations. In addition, the effect sizes for Koreans and Europeans were moderately correlated (r = 0.33–0.68). However, 61 variants were not replicated in both Koreans and Europeans. Our findings provide valuable information on effect sizes and statistical significance, which is essential to improve the assessment of disease risk using PRS analysis.

OBJECTIVE: This study examined the effect of social support on metabolic syndrome (MetS) among elderly population in a city in Korea. METHODS: A total of 352 people all over 60 years of age were analyzed from the data of the Korean Longitudinal Study on Cognitive Aging and Dementia. This study was started in 2010 and is in progress till date. We compared the documented diagnoses of MetS and Medical Outcome Study Social Support Survey at the baseline of the study and two years later. RESULTS: 315 were normal, 37 were developed after two years among subjects without MetS at baseline. When the level of social support was compared at baseline and then at the time of the reassessment two years later, the level had increased in the normal group and the level had not significantly changed for the MetS group. The findings documented at the two year mark indicate that the higher and stronger the level of social support, the lower the risk of developing MetS (odds ratio=0.053, p=0.040). CONCLUSION: The elderly with good social support are noted to be at lower risk in developing MetS as opposed to those with poor social support. It is apparent that adequate social support shows reduced prevalence of MetS among the elderly. Methods to identify strategies in improving social support networks are needed to expand public health resources and to better accommodate the community-based care of the elderly.
Aged* ; Cognitive Aging ; Dementia ; Diagnosis ; Humans ; Korea* ; Longitudinal Studies ; Outcome Assessment (Health Care) ; Prevalence ; Public Health

OBJECTIVE: This study aimed to examine whether educational stressors and relational stressors are associated with burnout in medical students and to test social support as a moderator between stressors and burnout. METHODS: A total of 263 medical students attending Gyeongsang National University composed the study sample. A standardized questionnaire was used to investigate educational and relational stressors, three dimensions of burnout, and social support of medical students. RESULTS: The findings showed that overall burnout is very high among Korean medical students, with 9.9% totally burned out. Educational and relational stressors were significantly associated with the risk of burnout in medical students after controlling for socio-demographics and health behaviors. Social support moderated educational and relational stressors on personal accomplishment, but did not moderate stressors on emotional exhaustion and depersonalization. CONCLUSION: Burnout level is substantially high among Korean medical students. Educational and relational stressors are significantly associated with burnout risk in Korean medical students. Social support had moderated educational and relational stressors on personal accomplishment. The results suggest that more social support for medical students is needed to buffer stressors on and burnout.
Burns ; Depersonalization ; Health Behavior ; Humans ; Students, Medical*

BACKGROUND/AIMS: The relationship between Crohn's disease and gallstones is established. However, the prevalence and risk factors for gallstones in patients with ulcerative colitis (UC) are not yet well understood. The aim of this study was to evaluate the prevalence and risk factors of gallstones in patients with UC. METHODS: This study was a retrospective single center study. A total of 87 patients with UC and 261 healthy controls were enrolled. Age, sex, and body mass index were matched. To investigate risk factors, the extent of UC, duration of disease, number of hospital admissions, and number of steroid treatments in patients with UC were evaluated. RESULTS: The prevalence of gallstones in patients with UC was 13.8%, whereas that in healthy controls was only 3.1% (P<0.001). For patients with UC, patients > or =50 years of age had a 3.6-times higher risk of gallstones compared to that in those <50 years of age, and the difference was statistically significant (odds ratio, 3.60; confidence interval, 1.03-12.61) in univariate analysis. There were no statistically significant disease-related risk factors for gallstones in UC patients. CONCLUSIONS: This is the first study of gallstone prevalence in Korean UC patients. In this study, patients with UC had a higher prevalence of gallstones compared to that in well-matched healthy controls. Age seemed to be a possible risk factor, and more studies are needed. Further prospective, large-scale studies will be required to confirm the risk factors for gallstones in UC patients.
Asymptomatic Diseases ; Body Mass Index ; Colitis, Ulcerative* ; Crohn Disease ; Gallstones* ; Humans ; Prevalence ; Retrospective Studies ; Risk Factors