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.

Purpose: Radiotherapy (RT) remains a cornerstone of curative treatment for localized and locally advanced prostate cancer. However, dose escalation to improve tumor control is often constrained by the proximity of the rectum, which increases the risk of gastrointestinal (GI) and genitourinary toxicities. Biodegradable rectal spacers inserted between the prostate and rectum have emerged as an effective approach to reduce rectal radiation exposure. This guideline provides evidence-based recommendations on indications, contraindications, procedural standards, and clinical management for biodegradable rectal spacer insertion during prostate cancer RT. Materials and Methods: This guideline was developed by a multidisciplinary expert panel through a systematic review of the literature, analysis of international guidelines (National Comprehensive Cancer Network, European Association of Urology, American Society for Radiation Oncology), and expert consensus among radiation oncologists, radiologists, and urologists with clinical experience in spacer insertion. The strength of each recommendation and the level of evidence were classified according to the modified GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) system. Results: Spacer insertion is conditionally recommended (Grade C, Level I) for patients receiving definitive external-beam RT without rectal invasion. It reduces the high-dose rectal irradiation volume (V70–75) by >50%, decreases acute GI toxicity, and helps maintain bowel-related quality of life. However, the benefit for late severe toxicity (grade 2 or higher) remains debated in recent meta-analyses. Contraindications include rectal invasion, anatomical inaccessibility, infection, and material hypersensitivity. Procedures should be performed under local anesthesia in a sterile environment by trained physicians. Short-course antibiotics and simulator-based training, including completion of multiple supervised cases, are advised. Conclusion Biodegradable rectal spacer insertion is clinically validated and effective in reducing acute rectal toxicity. Although pivotal trials demonstrated a favorable procedural safety profile, real-world postmarket data include reports of rare but severe procedural complications. This guideline provides standardized recommendations tailored to Korean clinical practice while remaining consistent with international standards, emphasizing the importance of operator training and careful patient selection.

Objective: To evaluate ruminoreticular temperature and body activity after vaccination, stratified by pregnancy status. Methods: This prospective observational cohort study investigated ruminoreticular temperature and body activity in Hanwoo cows after experimental administration of FMD and LSD vaccines. Sixty-three Hanwoo cows (pregnant n = 23 [100–175 days], nonpregnant n = 40) were monitored using a rumen-insertable biosensor that records ruminoreticular temperature and activity every 10 min. Groups received FMD, LSD, simultaneous FMD/LSD, or saline (control). Outcomes were analyzed using analysis of covariance with age and parity as covariates. Results: In pregnant cows, simultaneous FMD/LSD vaccination increased ruminoreticular temperature at day 1 and returned to baseline by day 3; single-vaccine groups showed more prolonged elevations. In nonpregnant cows, simultaneous vaccination increased temperature at day 1, normalizing by day 3–4. Body activity did not differ among pregnant groups;in nonpregnant cows, the simultaneous group showed lower activity than single-vaccine groups on some days. Conclusions and Relevance: In pregnant Hanwoo cows, post-vaccination temperature increase may enhance the risk of abortion, stillbirth, and premature birth, but this cannot be concluded to be the effect of vaccination. Since vaccination is the sole prevention for infectious diseases, it is unavoidable. Therefore, further research on reproduction related side effects after simultaneous vaccination are needed, and the findings of this study may provide valuable data to support such investigations.

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.

Purpose: Autism spectrum disorder (ASD) exhibits heterogeneous developmental trajectories; however, longitudinal studies using the Korean Childhood Autism Rating Scale (K-CARS) are scarce. This study examined diagnostic changes and related developmental characteristics through repeated K-CARS assessments. Methods: We retrospectively reviewed the medical records of children who underwent repeated K-CARS assessments between May 2021 and December 2024 at Gyeongsang National University Hospital. Based on diagnostic status at the initial (T1) and follow-up (T2) evaluations, participants were classified as having persistent ASD (ASD at T1 and T2), emerging ASD (non-ASD at T1 but ASD at T2), or desisting ASD (ASD at T1 but non-ASD at T2). Developmental profiles were evaluated using the social quotient (SQ), visual-motor integration (VMI), and language quotients. Results: Forty-three children (32 boys; median age, 2.9 years at T1 and 4.3 years at T2) were included. Twenty-two met ASD criteria at T1, and 15 (68%) retained the diagnosis at T2. Across the cohort, 15 (35%) had persistent ASD, 21 (49%) had emerging ASD, and seven (16%) had desisting ASD. The desisting group showed higher baseline VMI and better outcomes at follow-up. The emerging group initially had higher SQ and VMI than the persistent group, but these differences disappeared over time. Higher baseline VMI was associated with desisting status and higher baseline SQ with emerging ASD (odds ratios, 3.14 and 2.59 per standard deviation increase, respectively; P=0.06 and P=0.07). Conclusion Early ASD diagnoses were generally stable yet variable, supporting repeated assessment. Baseline VMI and SQ may relate to later diagnostic changes.

Rectal cancer, which accounts for approximately 40% of colorectal cancers, remains a major clinical concern. Recent advances in diagnostic imaging, surgical techniques, radiotherapy, and systemic treatment have steadily improved rectal cancer outcomes. Considering this, the Korean Rectal Cancer Multidisciplinary (KRCM) Committee has aimed to provide clinicians and policymakers with up-to-date, evidence-based clinical practice guidelines to support optimal decision-making, reflecting current evidence, the Korean healthcare context, and patient values and preferences. The Clinical Practice Guidelines for Rectal Cancer version 2.0 were developed through multidisciplinary collaboration with related academic societies, building upon and updating the KRCM Clinical Practice Guidelines version 1.0 (titled “Multidisciplinary guidelines for the management of rectal cancer”). These consensus guidelines of the KRCM were established based on a comprehensive literature review, evidence synthesis, with recommendation development guided by the GRADE (Grading of Recommendations Assessment, Development and Evaluation) methodology, and consideration of applicability in real-world clinical practice under the national health insurance system. Each recommendation has been presented with its strength and level of evidence.

Background: Long working hours have been associated with adverse physical and mental health outcomes; however, evidence regarding their relationship with satisfaction with work environment remains limited, particularly when long working hours are defined using a specific daily threshold. This study examined the association between working ≥10 hours per day and satisfaction with work environment among Korean wage workers, focusing on the cumulative number of such workdays per month. Methods: This cross-sectional study analyzed data from the 7th Korean Working Conditions Survey. A total of 24,269 wage workers aged ≥18 years were included after excluding self-employed workers, unpaid family workers, shift workers, and respondents with missing data. Working ≥10 hours per day was categorized as 0, 1–9, and ≥10 days per month. Satisfaction with work environment was categorized as satisfied or dissatisfied. Multiple logistic regression analyses were conducted to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for dissatisfaction with work environment according to the number of long working days, adjusting for demographic and occupational characteristics. Results: Compared with workers who did not work ≥10 hours per day, those who worked 1–9 days and ≥10 days per month showed progressively higher levels of dissatisfaction with work environment. After adjustment for demographic and occupational factors, the odds of dissatisfaction with work environment were significantly higher among workers who worked ≥10 hours per day for 1–9 days per month (OR: 1.380; 95% CI: 1.145–1.665) and ≥10 days per month (OR: 2.106; 95% CI: 1.627–2.725), demonstrating a dose–response relationship. Conclusions Among the analytic sample of Korean wage workers included in this study, working ≥10 hours per day was associated with greater dissatisfaction with work environment, with a dose–response pattern according to the number of long working days per month.

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.