Sarcopenia is a major geriatric syndrome characterized by progressive loss of muscle mass and strength, resulting in disability and mortality. This narrative review synthesizes international consensus recommendations and Korean evidence to guide context-specific sarcopenia management strategies. PubMed, Embase, Cochrane Library, and KoreaMed (January 2000–November 2025) were searched, focusing on randomized trials, meta-analyses, systematic reviews, clinical practice guidelines, and large observational studies. Global diagnostic frameworks have evolved from muscle mass-based definitions toward multidimensional models that incorporate muscle strength and physical performance. Exercise and nutrition remain the mainstay treatments, with resistance-based training and adequate protein intake. Currently, pharmacologic options with proven clinical benefit are limited. In Korea, growing evidence supports the effectiveness of community-based sarcopenia interventions, underscoring the need for standardized, integrated delivery models that bridge the fragmented healthcare system and enable sustainable implementation.

Background: s/Aims: Phase angle (PhA), as measured by bioelectrical impedance analysis, provides insights into hydration and nutritional status, making it a prognostic indicator of frailty. While low preoperative PhA has been linked to postoperative complications in cancer patients, its predictive value in individuals undergoing pancreaticoduodenectomy (PD) has not been thoroughly investigated.This study aims to evaluate the clinical utility of preoperative PhA in predicting postoperative complications for patients undergoing PD. Methods: Among 41 patients who underwent PD at Seoul National University Hospital between September and December 2024, 35 were included in the analysis after excluding 6 patients who had concomitant blood vessel or other organ resections. Patients were divided into low (Comprehensive Complication Index [CCI] ≤ 20) and high (CCI > 20) complication groups based on the CCI, derived from the Clavien–Dindo classification. The differences in PhA between the two groups were analyzed, and logistic regression was performed to assess the relationship between PhA and CCI. Results: The mean PhA was significantly lower in the high-CCI group compared to the low-CCI group (5.7° vs. 6.7°, p = 0.025). Multivariate logistic regression analysis indicated that PhA (odds ratio: 0.17; 95% confidence interval: 0.04–0.68; p = 0.012) was an independent predictor of high CCI. A low preoperative PhA was associated with an increased risk of postoperative complications following PD. Conclusions Preoperative PhA may serve as a valuable predictive indicator of postoperative complications after PD, enabling the identification of patients who could benefit from preoperative prehabilitation, including nutritional support.

Background: We compared the immunoglobulin (IG) heavy chain (IGH) leader and FR1 primer sets to measure clone sizes and detect immunoglobulin heavy chain variable (IGHV) region somatic hypermutations (SHMs) in Korean patients with chronic lymphocytic leukemia (CLL). We also analyzed IGH and immunoglobulin kappa (IGK) to identify Korean-specific IGs in CLL. Methods: Next-generation sequencing (NGS)–based gene rearrangements and IGHV SHMs were assessed in 40 patients using IGH leader, IGH FR1, and IGK primers. Flow cytometry, karyotyping, interphase FISH, and NGS-based variant analyses were performed for 165 genes. Results: Clonal IGH and IGK rearrangements were detected in 100.0% and 97.5% of patients, respectively. Clonal size was generally smaller per NGS than per flow cytometry, particularly when using the IGH leader (median: 52.5%) versus the IGH FR1 primer set (73.2%). IGHV SHMs occurred in approximately 70% of patients; 10% showed primer set discrepancies. The incidence of IGHV SHMs was low in patients at high risk (i.e., with TP53 abnormalities; complex karyotypes; and ATM, NOTCH1, SF3B1, or BIRC3 variants). IGHV3 was the most common IGHV (58.3%), and IGHV4-34 was most frequently identified (14.6%). IGHV1 and IGHV1-69 usage differed significantly between Koreans and westerners. IGHJ4 was the most common IGHJ (56.3%). A single IGKV–IGKJ gene rearrangement was most frequently observed (18.9%), whereas intron-KDE was the most common rearrangement (30.6%). Conclusions NGS may underestimate CLL clonal size, particularly when using the IGH leader primer set. IGHV SHMs were inversely associated with negative prognostic factors.Our data suggest ethnic differences in CLL pathogenesis.

This study examined the associations of fall experiences with cognitive function and activities of daily living (ADL) disability among older adults. Methods: Using data from the 2023 National Survey of Older Koreans, a total of 9,816 individuals aged 65 years or older were analyzed. Independent samples t-tests, ANOVA, chi-square tests, linear regression, and logistic regression analyses were conducted. Additionally, subgroup regression analyses were conducted to identify socially vulnerable groups according to age group, education level, and caregiving expenses. Results: The analysis showed that cognitive function tended to be lower in individuals with fall experience (β=-0.44, p=.026), and the odds of ADL disability were higher among individuals with fall experience (odds ratio [OR]=2.04, 95% confidence interval [95% CI]=1.63~2.54). In addition, subgroup analyses showed that cognitive function was lower among individuals with fall experience in the ≥85 years group (β=- 1.30, p=.020) and among those with education at elementary school or below (β=-0.88, p=.001). The odds of ADL disability among those with fall experience were higher among those aged 65~74 years (vs. 75~84; OR=2.80, 95% CI=1.99~3.94) and ≥85 years (vs. 75~84; OR=2.59, 95% CI=1.38~4.84), those with higher education (vs. lower; OR=4.95, 95% CI=1.19~20.60), and those with no caregiving expenses (vs. any; OR=2.06, 95% CI=1.63~2.60). Conclusion: These findings provide important foundational data for both policy development and academic research. They highlight the need for a multifaceted approach to fall prevention and underscore its importance in enhancing the quality of life for the older adults.

This review summarizes the establishment of the 2025 Dietary Reference Intakes for Koreans (KDRIs), the third national standard for nutrient reference values in Korea. The 2025KDRIs build on lessons from revisions in 2010, 2015, and 2020, and chart a path forward by addressing 4 priorities: upgrading the scientific evidence base through systematic evaluation, strengthening intake monitoring using national survey data, advancing international harmonization, and responding to changes in the nutrition and health environment, including those associated with the coronavirus disease 2019 (COVID-19) pandemic. The scientific basis of the KDRIs was advanced by systematically evaluating the findings across exposure indicators, health assessment indicators, and the health outcomes, and reorganizing the indicators to estimate the nutrient requirements. Adequate Intake was set using explicit criteria when an Estimated Average Requirement could not be derived, data gaps, uncertain outcomes, and limited representativeness were documented. Key inputs, including coefficients of variation and uncertainty factors, as well as life stage estimation procedures, were re-evaluated in alignment with current evidence and international standards. The 2025 KDRIs incorporate intake evidence from the Korea National Health and Nutrition Examination Survey to inform policy and practice and support intake monitoring. For international harmonization, the NUQUEST-based literature framework was updated, and recent DRIs from other countries were compared. The shifts in anthropometric characteristics and dietary intake patterns observed during the COVID-19 pandemic were considered to reflect a changing context. The review identified remaining challenges for future revisions, including validating Koreanspecific indicators, developing evidence for infants and older adults, stronger translation of reference values into policy and practice, prioritizing of nutrients for future review within the 5-year revision cycle. Together, these advances will position the 2025 KDRIs as a science-based national reference integrating policy, practice, and evidence to support implementation aimed at improving nutritional status and healthy life expectancy in Korea.

Dietary protein is a crucial macronutrient for systemic homeostasis, and the global interest in protein supplements has surged because of their roles in muscle synthesis, immune function, and sarcopenia prevention. In South Korea, the proportion of energy derived from protein has increased steadily over the past decade, reflecting a significant shift in dietary patterns toward greater reliance on protein. Concurrently, a wide range of protein- and amino acidbased processed foods and dietary supplements has been developed and actively consumed.Nevertheless, comprehensive data on the prevalence of protein supplement users, their characteristics across different life stages, and the contribution of supplements to total daily protein requirements are lacking. Unlike other macronutrients, the human body lacks a dedicated reservoir for protein storage, necessitating a continuous dietary supply to support protein turnover, particularly for older adults facing anabolic resistance and individuals with high physical demands. Although clinical evidence highlights that protein supplementation, particularly when combined with resistance exercise, effectively improves muscle mass and physical performance, the magnitude of these benefits remains inconsistent across different life stages and protein sources. Conversely, emerging concerns about the potential metabolic risks from chronic overconsumption suggest that the validity and safety of protein supplementation are unclear, highlighting the need for a precision nutrition approach. Thus, this review evaluates the status of protein supplement intake among Koreans, synthesizes evidence on its physiological benefits and drawbacks and examines international trends and regulatory frameworks. Developed as part of the technical assessment for the 2025 revision of the Dietary Reference Intakes for Koreans, this review addresses the current lack of longterm safety data on chronic protein overconsumption. It provides a foundational framework for evidence-based dietary guidelines and serves as a critical scientific basis for establishing future tolerable upper intake levels and nutrition policies for protein supplement use in Korea.

Objectives: This study, part of the ongoing Korean National Burden of Disease (KNBD) updates, assesses disability-adjusted life years (DALYs) and disability-adjusted life expectancy (DALE) in Korea, taking into account the effects of coronavirus disease 2019 and emphasizing the importance of analyzing these metrics jointly. Methods: Data were obtained from Statistics Korea, the National Health Insurance Service, and the Korea Disease Control and Prevention Agency. DALYs and DALE were calculated using an incidence-based approach, following disease classification, disability weights, and estimation procedures consistent with prior KNBD research. Results: Compared with earlier estimates, DALYs showed a slight decline in 2020 followed by an increase in 2021, with this pattern observed across all income quintiles. For DALE, both men and women experienced modest gains relative to earlier studies; however, a decrease occurred across all income levels in 2021 compared with 2020. Regional disparities in DALE also narrowed beginning in 2020, with a more marked reduction among women. Conclusions Unlike previous studies, this research presents DALYs and DALE concurrently, offering a more comprehensive perspective on summary measures of population health. The post-2020 rise in DALYs underscores the growing need for effective chronic disease management. Additionally, widening income-based disparities in DALE highlight the urgency of addressing health inequities. Continued monitoring and updates of DALYs and DALE are necessary to understand and respond to these evolving trends.

Objective: This study aims to compare the incidence of active tuberculosis (TB) among Korean patients with rheumatoid arthritis (RA) initiating treatment with tumor necrosis factor inhibitors (TNFi) or tofacitinib. Methods: Using the Korean National Health Insurance database, we conducted a nationwide, retrospective cohort study of RA patients who started TNFi or tofacitinib therapy between 2015 and 2018. We calculated the incidence rates of active TB based on the treatment type and results from latent tuberculosis infection (LTBI) screening tests. A multivariable Cox proportional hazards model was employed to evaluate the risk of active TB in RA patients beginning TNFi or tofacitinib treatment. Results: Among 3,382 RA patients (596 on tofacitinib and 2,786 on TNFi), LTBI screening was predominantly conducted using the IGRA (interferon-gamma release assays) test. Of these patients, 624 (18.5%) with a positive LTBI test received prophylactic treatment. No cases of active TB occurred in tofacitinib users, while 32 cases were observed in TNFi users. The adjusted hazard ratio for active TB in LTBI-positive patients was 5.47 (95% confidence interval 2.74 to 10.92) compared to LTBI-negative patients.In subgroup analyses, TB incidence was significantly higher among individuals aged over 65 years. Conclusion Despite LTBI treatment, active TB remains prevalent among RA patients on TNFi therapy and in those with positive LTBI tests.

Purpose: This developmental study explored the conceptual feasibility and applicability of a metaverse-based clinical assessment platform as a complementary tool to conventional objective structured clinical examinations in undergraduate medical education. Methods: A targeted literature review and expert consensus process were conducted to identify domains of clinical competence in which metaverse technologies could provide added value. Based on these findings, prototype virtual patient simulations were developed within a metaverse environment. Large language models (LLMs) were integrated to support dynamic, interactive history-taking simulations, and pilot modules for physical examination were also created. Results: Integration of LLMs into virtual patient scenarios enabled realistic, context-sensitive medical interviews, facilitating interactive dialogue between examinees and simulated patients. In contrast, physical examination modules faced technical limitations, particularly in replicating procedures requiring tactile or haptic feedback, such as palpation and percussion. Nevertheless, the metaverse environment enabled delivery of consistent and reproducible scenarios, supporting objective assessment of communication and diagnostic reasoning skills. Conclusion Metaverse-based simulations augmented by LLMs offer a promising approach to scalable and standardized clinical assessment, particularly within cognitive and interpersonal competency domains. Although current technological constraints limit the fidelity of physical examination simulations, rapid advancements in immersive and haptic technologies may help overcome these barriers in the near future. Further research is needed to evaluate the educational efficacy, validity, and feasibility of deploying such platforms in summative, high-stakes assessment contexts.