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.

Purpose: This study aims to determine whether the translucency-based clinical grade of pterygium shows independent relationships with anterior and posterior corneal curvature and anterior wavefront aberrations, with adjustment for horizontal invasion length (HIL) measured by anterior segment (AS) swept-source optical coherence tomography (SS-OCT). Methods: This study involved 53 eyes from 51 patients diagnosed with primary nasal pterygium. The clinical grade of the pterygium was evaluated using T grade based on the fibrovascular translucency. AS SS-OCT (Anterion, Heidelberg Engineering) provided HIL (in millimeters), thickness (in micrometers), anterior/posterior keratometry at the 3.0-mm ring, and anterior corneal wavefront metrics within a 6.0-mm zone. The device was also used to evaluate the magnitudes for the individual first-to fourth-order aberrations of the anterior corneal fields. Also, the fourth- to seventh-order root mean square (RMS), RMS lower-order aberration (LoA), and RMS higher-order aberration (HoA) values were collected. For statistical analysis, Spearman rank correlation test and Pearson correlation test were performed, along with partial correlation test adjusted for HIL. Results: The mean age of subjects was 59.3 ± 11.4 years, and 51.0% were female. T grade correlated positively with HIL. HIL showed strong associations with anterior simulated keratometry (Sim K) average, anterior Sim K steep, anterior Sim K flat, and anterior corneal astigmatism—but not with posterior corneal parameters. HIL also showed significant correlations with multiple anterior corneal wavefront parameters. After adjustment for HIL, T grade remained independently correlated with anterior Sim K flat, RMS LoA, and defocus; no significant relationships were observed with other Zernike terms or posterior metrics. Additionally, T grade was positively correlated with pterygium thickness. Conclusions T grade adds independent, complementary information (associations with flat keratometry, LoA RMS, and defocus) even after controlling for HIL. Incorporating T grade into preoperative assessment may improve estimation of optical burden and surgical prognosis.

Background: and Purpose Although gastrointestinal (GI) surgery can affect drug efficacy, its impact on oral anticoagulants (OACs) remains unclear. This study investigated the impact of GI surgery on the comparative effectiveness and safety of direct oral anticoagulants (DOACs) versus warfarin in atrial fibrillation (AF). Methods: Using a nationwide South Korean claims database, AF patients prescribed OACs between 2015 and 2021 were analyzed. The primary outcome was ischemic stroke, and secondary outcomes were major bleeding, all-cause death, and composite outcome (ischemic stroke, major bleeding, all-cause death). Outcomes were compared by OAC type (DOAC vs. warfarin) and GI surgery status using inverse probability of treatment weighting and a Fine–Gray subdistribution hazard model with time-varying covariates. Results: Among 388,214 AF patients (mean age, 71.9 yr; 42.7% male), 6,907 (1.8%) underwent GI surgery. The effect of GI surgery differed between warfarin and DOACs for ischemic stroke (Pint= 0.018), with increased risk for warfarin (adjusted HR [aHR]: 2.32; 95% confidence interval [CI] 1.17–4.62), but not for DOACs (aHR: 0.97 [95% CI 0.77–1.22]) after surgery. Effects of surgery on major bleeding, all-cause death, and composite outcome did not differ. In post–GI surgery setting, DOACs demonstrated lower ischemic stroke risk (aHR: 0.35 [95% CI 0.17–0.72]) and comparable risks for other outcomes. Exploratory analyses by surgery location suggested a more favorable profile of DOACs after upper GI surgery. Conclusions In AF patients, GI surgery significantly increased ischemic stroke risk among warfarin users, but not among DOAC users. DOACs showed generally favorable profiles after GI surgery and may remain a reasonable anticoagulant, with potentially more favorable profile after upper GI surgery.

Background: and Purpose Whole-exome sequencing (WES) is a valuable tool for identifying causative mutations in adult moyamoya disease (MMD), thereby advancing our understanding of the genetic mechanisms underlying this condition. Here, we conducted the first WESbased association study aimed at identifying genetic modifiers implicated in MMD. Methods: This WES study involved 160 patients with MMD and 189 controls from a multicenter hospital-based biobank, and evaluated combined annotation-dependent depletion (CADD) scores. Mutant-allele frequencies were compared in 369,121 individuals derived from the UK Biobank (UKB) WES. Mutant-allele risk scores (MARSs) were created based on WESidentified mutations. Gene-based association analyses and pooled analyses in East-Asian populations were further performed. Results: Fourteen mutations reached the genome-wide significance criterion (p<5×10-8 ), among which the p.R4810K mutation in the ring finger protein 213 gene (RNF213) showed the strongest significance (odds ratio=117.4, p=8.54×10-24 ). Notably, two mutations—p.G576S (alpha-glucosidase [GAA]) and p.D54N (charged multivesicular body protein 6 [CHMP6])— exhibited high CADD scores of 32 and 25, respectively, whereas the RNF213 p.R4810K mutation demonstrated a moderate deleteriousness score of 10.63. Fourteen mutations exhibited significant differences in allele frequencies between patients and UKB controlled data (p<1×10-8 ).The MARS9 model (incorporating nine missense mutations) showed better predictability for MMD (90.89%). The analysis of gene-based associations revealed four candidate genes: GAA, RNF213, CHMP6, and CARD14 (p=5×10-19 to 4×10-7 ). The subsequent pooled analyses validated four mutations in East Asian populations: p.V1195M, p.D1331G, p.S2334N, and p.R4810K (p<3×10-8 ). Conclusions This pioneering study has corroborated the significance of p.R4810K and identified several causative mutations predisposing patients to MMD, which helps to improve the understanding of its polygenetic nature.

Purpose: Due to chronic toxicity, tacrolimus-sparing is an important issue in kidney transplant recipients (KTRs). Several studies have shown that bisphosphonate use is associated with favorable graft outcomes in KTRs. We investigated whether the association between tacrolimus trough levels (TTLs) and graft outcomes differed according to bisphosphonate use in KTRs. Materials and Methods: We conducted a retrospective study encompassing 1441 KTRs who were administered tacrolimus-based immunosuppressants. The primary exposure was a time-dependent cross-product of TTLs (low TTLs vs. normal-high TTLs with a reference of 6 ng/mL) and bisphosphonate use. Two primary outcomes were evaluated: overall graft loss (death or conversion to kidney replacement) and an estimated glomerular filtration rate (eGFR) <30 mL/min/1.73 m 2 . Results: During the median follow-up of 6.1 (3.4–9.7) years, overall graft loss occurred in 157 (10.9%) patients. Cox regression revealed that normal-high TTLs without bisphosphonate use were associated with a reduced risk of overall graft loss [adjusted hazard ratio (aHR), 0.65; 95% confidence interval (CI), 0.45–0.95] compared to low TTLs without bisphosphonate use. The use of bisphosphonate in conjunction with normal-high TTLs correlated with an even lower risk of overall graft loss (aHR, 0.25; 95% CI, 0.08–0.80) compared with low TTLs without bisphosphonate use. In patients with low TTLs, bisphosphonate use was associated with a reduced risk of overall graft loss compared with non-use (aHR, 0.20; 95% CI, 0.09–0.43). Similar trends were observed in the eGFR outcome. Conclusion The use of bisphosphonate was associated with favorable graft outcomes, even with low TTLs. Incorporating bisphosphonate into a conventional immunosuppressant regimen may potentially reduce tacrolimus requirement.

Background: Dual energy X-ray absorptiometry (DXA) measurements vary among instruments from different manufacturers. This study aimed to assess the correlation between bone mineral density (BMD) and body composition measured by the GE Lunar Prodigy and Hologic Horizon W DXA systems and to develop conversion equations. Methods: A total of 120 healthy volunteers (59 males, 61 females) aged 20 to 70 years were scanned on both DXA systems on the same day. BMD was measured at the lumbar spine (L1-L4) and bilateral femurs. Body composition parameters were measured for the whole body and regional sites. Bland-Altman analysis, Pearson correlation, and concordance correlation coefficient (CCC) were used to assess agreement. Linear regression was performed to derive conversion equations. Results: The Hologic system measured BMD values 14% to 20% lower at the lumbar spine and 8% to 17% lower at femoral sites compared to the GE Lunar system (all P<0.0001). Lean mass values were 4% to 10% lower on the Hologic system. Very strong correlations were observed for both BMD (r=0.944-0.980) and lean mass (r=0.963-0.984). Cross-calibration equations were developed for all measurement sites. Conclusions Despite significant systematic differences, there was very high correlation between the two DXA systems. The conversion equations can facilitate comparison of measurements between these systems in clinical practice and research.

Purpose: To analyze anterior, posterior, and total corneal refractive profiles and thickness using anterior segment (AS) sweptsource optical coherence tomography (SS-OCT) in Stevens-Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN) patients. Methods: This retrospective study compared 23 eyes from 14 patients with SJS/TEN with 23 eyes from 14 age- and sexmatched controls. AS SS-OCT measured corneal refractive profiles and pachymetry. Parameters included anterior, posterior, and total corneal power values, posterior to anterior curvature ratio, maximal corneal power, and thickness profiles. The SJS/TEN group was subdivided based on corneal opacity presence (subgroup A) or absence (subgroup B). Results: The SJS/TEN group showed significantly higher corneal astigmatism and maximal corneal power values for both anterior and posterior curvatures. Steep total corneal power and total corneal astigmatism were higher in the SJS/TEN group. The thinnest corneal thickness was lower, and its distance from the corneal vertex was greater in the SJS/TEN group. Subgroup analysis revealed that these differences were primarily attributed to the presence of corneal opacity. Additionally, automated keratometry of the anterior corneal surface showed significantly higher values, including steep, flat, and average keratometry and corneal astigmatism, in the SJS/TEN group. Conclusions AS SS-OCT shows significant alterations in both anterior and posterior corneal curvatures in patients with SJS/TEN. These findings emphasize the importance of considering posterior corneal curvature changes in pre-cataract surgery assessments and contact lens prescriptions for patients with SJS/TEN.

Radiofrequency ablation (RFA) is a minimally invasive treatment modality used as an alternative to surgery in patients with benign thyroid nodules, recurrent thyroid cancers (RTCs), and primary thyroid microcarcinomas. The Korean Society of Thyroid Radiology (KSThR) initially developed recommendations for the optimal use of RFA for thyroid tumors in 2009 and revised them in 2012 and 2017. As new meaningful evidence has accumulated since 2017 and in response to a growing global interest in the use of RFA for treating malignant thyroid lesions, the task force committee members of the KSThR decided to update the guidelines on the use of RFA for the management of RTCs based on a comprehensive analysis of current literature and expert consensus.

This review examines the challenges associated with occupational disease surveillance in Korea, particularly emphasizing the limitations of current data sources such as the Industrial Accident Compensation Insurance (IACI) statistics and special health examinations. The IACI system undercounts cases due to its emphasis on severe diseases and restrictions on approvals. Special health examinations, although they cover a broad workforce, are constrained by their annual scheduling, which leads to missed acute illnesses and subclinical conditions. The paper also explores the history of occupational disease surveillance in Korea, highlighting the fragmented and disease-specific approach of earlier systems. The authors introduce the newly established Korea Occupational Disease Surveillance Center (KODSC), a comprehensive nationwide system designed to gather, analyze, and interpret data on occupational diseases through a network of regional centers. By incorporating hospital-based surveillance and focusing on acute poisonings and other sentinel events, the KODSC aims to overcome the limitations of previous systems and promote collaboration with various agencies. Although it is still in the early stages of implementation, the KODSC demonstrates potential for improving data accuracy and contributing valuable insights for public health policy.

Connective tissue disease (CTD), comprising a range of autoimmune disorders, is often accompanied by lung involvement, which can lead to life-threatening complications. The primary types of CTDs that manifest as interstitial lung disease (ILD) include rheumatoid arthritis, systemic sclerosis, Sjögren’s syndrome, mixed CTD, idiopathic inflammatory myopathies, and systemic lupus erythematosus. CTD-ILD presents a significant challenge in clinical diagnosis and management due to its heterogeneous nature and variable prognosis. Early diagnosis through clinical, serological, and radiographic assessments is crucial for distinguishing CTD-ILD from idiopathic forms and for implementing appropriate therapeutic strategies. Hence, we have reviewed the multiple clinical manifestations and diagnostic approaches for each type of CTD-ILD, acknowledging the diversity and complexity of the disease. The importance of a multidisciplinary approach in optimizing the management of CTD-ILD is emphasized by recent therapeutic advancements, which include immunosuppressive agents, antifibrotic therapies, and newer biological agents targeting specific pathways involved in the pathogenesis. Therapeutic strategies should be customized according to the type of CTD, the extent of lung involvement, and the presence of extrapulmonary manifestations. Additionally, we aimed to provide clinical guidance, including therapeutic recommendations, for the effective management of CTD-ILD, based on patient, intervention, comparison, outcome (PICO) analysis.