Purpose: The chromodomain helicase DNA-binding (CHD) protein family comprises adenosine triphosphate-dependent chromatin remodelers that regulate chromatin structure and gene expression. Pathogenic CHD2 variants are associated with neurodevelopmental phenotypes, but these genotype–phenotype correlations remain unclear. This study aimed to delineate the clinical and genetic features of patients with CHD2-related disorders and to explore the associated genotype–phenotype relationships. Methods: Among 22 patients with pathogenic or likely pathogenic CHD2 variants identified using a customized 172-gene neurodevelopmental and epilepsy panel, 19 with sufficient clinical data were included. Demographic, clinical, neuroimaging, electroencephalographic, and genetic data were retrospectively reviewed. Results: Eighteen pathogenic or likely pathogenic variants were identified, including eight novel variants: nine nonsense (50.0%), five splice-site (27.8%), two missense (11.1%), and two exon deletions (11.1%). All patients had epilepsy, with a median age of seizure onset of 2.33 years. Comorbidities included global developmental delay (89.5%), intellectual disability (82.0%), and neuropsychiatric symptoms (47.4%). Seizure types were heterogeneous, with a predominance of generalized-onset seizures, and 13 patients (68.4%) achieved seizure freedom. Marked phenotypic variability was observed: two unrelated patients with the same truncating variant had different developmental and seizure-related profiles, a symptomatic child with an inherited exon 5 deletion contrasted with her asymptomatic father, and a patient with an exon 17–29 deletion exhibited relatively mild features. Conclusion Epilepsy was a consistent manifestation in this study and was accompanied by diverse developmental and neurobehavioral features, with substantial genotype–phenotype discordance. Further research on genotype–phenotype correlation is warranted.

Purpose: Endoscopic submucosal dissection (ESD) has become a standard minimally invasive treatment for selected patients with early gastric cancer (EGC). This study presents the first nationwide survey of patients with EGC treated with ESD in 2023, conducted by the Korean College of Helicobacter and Upper Gastrointestinal Research. Materials and Methods: Data were retrospectively collected from participating referral centers across Korea using a standardized case report form covering patient characteristics, tumor features, procedural details, histopathological findings, and clinical outcomes.Descriptive and comparative analyses were conducted to summarize nationwide ESD practice patterns and outcomes. Results: Data from 5,460 ESD cases from 5,250 patients across 27 institutions were analyzed. The mean age was 67.4 years, with 74.1% males. Multiple synchronous lesions were identified in 3.7%. Most lesions were located in the lower third of the stomach (64.0%), and differentiated-type adenocarcinomas accounted for 87.8%. The en bloc and complete resection rates were 99.2% and 91.4%, respectively. Curative resection was achieved in 80.5%, whereas local non-curative resection (L-NCR) and surgical non-curative resection (S-NCR) were identified in 2.8% and 16.7%, respectively. Additional surgery was performed more frequently in patients with S-NCR than in those with L-NCR (59.3% vs. 24.7%). The bleeding and perforation rates were 3.6% and 0.9%, respectively, and were mostly managed conservatively or endoscopically. The median length of hospitalization was 4.0 days. Conclusions This first nationwide survey provides a comprehensive overview of the current practice of EGC treatment using ESD in Korea, demonstrating high technical success and safety, and establishing a baseline dataset for future longitudinal research.

Purpose: Chronic myeloid leukemia (CML) in children, adolescents, and young adults is rare and differs from older adults. This study evaluated the outcomes of allogeneic hematopoietic stem cell transplantation (HSCT) in young Korean CML patients during the tyrosine kinase inhibitor (TKI) era. Materials and Methods: A retrospective analysis of 35 CML patients aged < 40 years who underwent allogeneic HSCT from 2009 to 2019 was conducted using Korean Blood and Marrow Transplantation Registry data. Patients were grouped by age < 20 years at HSCT (group 1, n=15) and 20-40 years at HSCT (group 2, n=20). Survival outcomes including overall survival (OS), relapse-free survival (RFS), and event-free survival (EFS) were analyzed using the Kaplan-Meier method. Results: The median time between diagnosis and HSCT was 8.9 months. All the patients achieved engraftment but platelet recovery was significantly slower in group 1 (p=0.034). Acute and chronic graft-versus-host disease occurred in 54.3% and 34.3%, respectively. Five-year OS, RFS, and EFS rates of total patients were 66.8%, 50.8%, and 47.6%, with better OS was observed in group 1 by multivariable analysis (p=0.048). Disease status at HSCT was a significant predictor of OS (p=0.028), RFS (p=0.003), and EFS (p=0.004). Disease progression occurred in 13 out of 35 patients (37.1%); treatment-related mortality accounted for 63.6% of deaths (7 out of 11). Conclusion When performed at a younger age, allogeneic HSCT result in superior outcome in CML. Achieving remission before HSCT is critical for improved outcomes, highlighting the importance of pretransplant remission via optimal TKI strategies and minimal residual disease monitoring.

Limited data exist regarding the real-world practices and clinical outcomes in patients with ischemic heart failure with reduced left ventricular ejection fractions (LVEFs).Using nationwide registry data from South Korea, we aimed to investigate long-term outcomes and clinical practices, especially implantable cardioverter defibrillators (ICDs) implantation, in patients with reduced LVEFs at least 40 days after acute myocardial infarction (AMI). Of 13,056 patients with AMI between 2011 and 2015, we analyzed 350 (median age, 66 years [interquartile range, 56-75]) who had LVEFs <40% on follow-up transthoracic echocardiogram 40 days after the index event. The primary outcome was cardiac-cause mortality at 3 years. Secondary outcomes comprised major cardiovascular events as well as outcomes defined by the use of ICDs, cardiac resynchronization therapy defibrillators (CRT-Ds), and electrophysiology studies. Among 350 patients, 39 (11.1%) died from cardiac causes during 3 years of follow-up. Eleven (3.1%) were hospitalized for ventricular tachycardia. The rate of ICD or CRT-D implantation up to 3 years was 5.7% (20/350). Cox time-to-event analysis revealed older age, LVEF <30%, diabetes mellitus, and previous MI or revascularization as positively associated with cardiac death, whereas the use of statins and body weight <67 kg were negatively associated. This nationwide Korean registry demonstrated that only 5.7% of patients who had reduced LVEFs after 40 days of AMI underwent ICD implantations over 3 years. Considering the high mortality, concerted efforts are needed to improve clinical outcomes for patients who may have been candidates for ICD implantation.

Subglottic stenosis (SGS) and tracheal stenosis (TS) are rare conditions that can cause significant breathing difficulties and, if not properly managed, may lead to life-threatening complications. Despite their clinical importance, debate continues regarding the optimal management of adult SGS and TS, and no comprehensive guidelines have been established to date. The Korean Bronchoesophagological Society appointed a task force to develop clinical practice guidelines with the goal of providing evidence-based recommendations for managing SGS and TS in adults. The task force conducted a systematic review of the relevant literature by searching PubMed, Embase, and the Cochrane Library using predefined search terms aligned with key clinical questions. The quality of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach, which also informed the formulation and reporting of the recommendations. The strength of each recommendation reflects the guideline panel’s confidence that the benefits of an intervention outweigh its risks for eligible patients. After drafting the guidelines, feedback was obtained through Delphi questionnaires completed by members of the Korean Bronchoesophagological Society. Ultimately, the committee developed 17 evidence-based recommendations across four categories: initial evaluation, medical management, surgical treatment, and postoperative management and rehabilitation. These guidelines aim to support clinicians in delivering optimal care to adult patients with SGS and TS.

Objectives: Cyberbullying is a modern form of violence involving intentional harassment through electronic devices. We aimed to investigate how psychological characteristics differ based on cyberbullying involvement, identify the psychological factors associated with cyberbullying, and examine whether these factors vary by gender. Methods: A survey was conducted with 449 middle school students in Cheongju, Korea. Participants were categorized into four groups based on their involvement: Neither (N), Victim (V), Perpetrator (P), and Victim-Perpetrator (VP). Psychological characteristics were assessed using the Beck Depression Inventory (BDI), Self-Esteem Scale, and Strengths and Difficulties Questionnaire (SDQ). We compared these characteristics across the four groups and examined their influence on cyberbullying involvement by gender. Results: Overall, 31.8% of participants were involved in cyberbullying, with the VP group being the largest (17.1%) among them. The VP group exhibited more severe psychopathology than the N group across most internalizing and externalizing problems. SDQ-Conduct Problems subscale scores were significantly associated with victimization and perpetration. For female participants, high SDQEmotional Symptoms subscale scores were associated with greater victimization, and high BDI scores increased the risk of belonging to the VP group. No variables significantly increased the risk of belonging to the VP group among male participants. Conclusion Adolescents who are both victims and perpetrators of cyberbullying face the most significant psychological difficulties.Factors associated with cyberbullying involvement vary by gender, highlighting the need for tailored gender-specific prevention and intervention strategies.

Background: With the aging population and advancements in medical care worldwide, the number of older patients with end-stage kidney disease continues to rise. This study aimed to identify factors associated with osteoporosis and osteopenia in older patients undergoing incident hemodialysis and assess their impact on mortality. Methods: We analyzed a large multicenter retrospective cohort of patients aged ≥70 years undergoing incident hemodialysis to identify factors associated with osteoporosis using logistic regression analysis and to assess the association of death with osteoporosis and osteopenia using Cox multivariable analysis. Results: Among 710 patients, 39.0% and 19.6% had osteoporosis and osteopenia, respectively. Osteoporosis was significantly associated with female sex, a history of fractures, and the absence of phosphate binder use. During a median follow-up of 36.8 months, 348 participants (58.8%) died. Mortality rates were the highest in the osteoporosis group (79.8%), followed by the osteopenia (77.2%) and normal bone mineral density (BMD) groups (35.2%). Cox regression analysis revealed that even after adjusting for covariates, the osteoporosis group was significantly associated with a higher mortality risk than the normal BMD group. Osteoporosis at the start of hemodialysis was significantly associated with higher mortality. Conclusion We should consider the importance of bone health in patients undergoing incident hemodialysis and pay attention to the use of phosphate binders and fracture prevention.

Background: Obesity is a well-known risk factor for chronic kidney disease and its progression. However, the impact of obesity on the renal function of the elderly population is uncertain. We investigated the association between obesity and renal outcomes in the elderly. Methods: We analyzed 130,504 participants from the Korean National Health Insurance Service-Senior cohort. Obesity was classified according to body mass index (BMI), sex-specific waist circumference (WC), and the presence of metabolic syndrome. The primary outcome was renal function decline, defined as a decline in the estimated glomerular filtration rate (eGFR) of at least 50% from baseline or new-onset end-stage renal disease. Results: During a follow-up period of 559,531.1 person-years (median, 4.3 years), 2,486 participants (19.0%; incidence rate of 4.44 per 1,000 person-years) showed renal function decline. A multivariate Cox proportional hazards model revealed that BMI/WC was not associated with renal function decline. However, the group with metabolic syndrome had a significantly increased risk of renal function decline compared to the group without metabolic syndrome (adjusted hazard ratio [HR], 1.24; 95% confidence interval [CI], 1.13–1.36). Compared with the non-metabolic syndrome group, the adjusted HRs (95% CI) for participants with one through five components were 0.96 (0.84–1.11), 1.10 (0.96–1.27), 1.24 (1.06–1.45), 1.37 (1.12–1.66), and 1.99 (1.42–2.79), respectively (p for trend < 0.001). Conclusion In elderly Korean adults, metabolic syndrome and the number of its components were associated with a higher risk of renal function decline, but BMI or WC was not significant.

Background and Objectives: Certain medications are associated with ototoxicity. This study assesses drug-induced ototoxicity in South Korea by analyzing the Korean national health data. Subjects and Methods: Hospital records of National Health Insurance members from 2009 to 2016 were reviewed. Data were compared between patients with and without hearing loss (HL). Individuals with HL were identified as having a primary diagnosis code for sensorineural HL or another type of HL in at least one outpatient or inpatient record according to the International Classification of Diseases-10. Results: The members in the HL group increased slightly from 0.8% to 1.0% relative to the total sample, compared with 99.2% to 99.0% among the controls. The proportion of males in the HL group ranged from 45.6% to 47.6%, compared with 48.4% to 48.8% among the controls. The proportion of those aged ≥65 years in the HL group increased from 34.1% to 41.4%, compared with 10.6% to 13.3% among the controls. Hypertension prevalence (24.7%-25.7%) in the HL group was higher than that in the control group (12%-12.6%). Diabetes prevalence in the HL group was 10.6%-12.3%, compared with 4.4%-5.9% among the controls. The use of proton pump inhibitor components increased, particularly esomeprazole magnesium trihydrate and rabeprazole sodium, whereas the usage of pantoprazole sodium sesquihydrate and revaprazan was high initially but declined subsequently. The usage of painkillers such as acetaminophen, loxoprofen sodium, and ibuprofen remained high, and antibiotics such as cephalosporins indicated the highest usage. However, the use of penicillin antibiotics such as amoxicillin decreased significantly. Anticancer agents showed relatively low usage compared with other drug categories, whereas antihistamines showed extremely high usage across all years, with a continual increase. Conclusions These correlations and the underlying mechanisms necessitate further investigation, as several medicines have been linked to an increased risk of HL.

Objective: As the demand for community mental health services continues to grow, the need for well-equipped and organized services has become apparent. This study aimed to optimize the roles and infrastructure of mental health services, by establishing, among other initiatives, standardized operating models. Methods: The study was conducted in multiple phases from May 12, 2021, to December 29, 2021. Stakeholders within South Korea and metropolitan mental health welfare centers were targeted, but addiction management support centers, including officials, patients, and their families, were integrated as well. A literature review and survey, focus group interviews, a Delphi survey, and expert consultation contributed to comprehensive revisions and improvements of the mental health service model. Results: The proposed model for community mental health welfare centers emphasizes the expansion of personnel and infrastructure, with a focus on severe mental illnesses and suicide prevention. The model for metropolitan mental health welfare centers delineates essential tasks in areas such as project planning and establishment, community research, and education about severe mental illnesses. The establishment of a 24-hour emergency intervention center was a crucial feature. In the integrated addiction support center model, the need to promote addiction management is defined as an essential task and the establishment of national governance for addiction policies is recommended. Conclusion This study proposed standard operating models for three types of mental health service centers. To meet the increasing need for community care, robust mental health service delivery systems are of primary importance.