Future Blood Debt: Projecting Blood Supply and Demand of Korea Based on Subnational Population Projections (2021-2050).

BACKGROUND: South Korea faces a critical challenge with its rapidly declining fertility rates and an increasingly aging population, which significantly impacts the country's blood supply and demand. Despite these nationwide trends, regional disparities in blood supply and demand have not been thoroughly studied. METHODS: This research utilized blood donation data from the Korean Red Cross and blood transfusion data from the Health Insurance Review and Assessment Service. We analyzed these datasets in conjunction with regional population projections to simulate blood supply and demand from 2021 to 2050 across South Korea. Sensitivity analyses were conducted to assess the impact of various factors, including the number of donors, age eligibility criteria for donations, frequency of donations, and blood discard rates. RESULTS: Our projections indicate a decreasing trend in blood supply, from 2.6 million units in 2021 to 1.4 million units by 2050, while demand is expected to peak at 5.1 million units by 2045 before declining. Metropolitan areas, particularly Gyeonggi Province, are projected to experience the most severe shortages. Sensitivity analyses suggest that increasing the donation frequency of existing donors and relaxing age eligibility criteria are more effective strategies in addressing these imbalances than merely increasing the number of new donors. Blood discard rates showed minimal impact on the overall blood shortage. CONCLUSION: The findings emphasize the urgent need for targeted strategies to mitigate national and regional blood supply shortages in South Korea. Encouraging frequent donations from experienced donors and broadening eligibility criteria are critical steps toward stabilizing the blood supply amidst demographic shifts. These strategies must be prioritized to address the impending regional disparities in blood availability.

Sarcopenia as the Mobility Phenotype of Aging: Clinical Implications.

Sarcopenia, which is characterized by an age-related decline in muscle mass and function, poses significant challenges to geriatric care. Its definition has evolved from muscle-specific criteria to include muscle mass, muscle function, and physical performance, recognizing sarcopenia as a physical frailty. Sarcopenia is associated with adverse outcomes, including mortality, falls, fractures, cognitive decline, and admission to long-term care facilities. Neuromechanical factors, protein-energy balance, and muscle protein synthesis-breakdown mechanisms contribute to its pathophysiology. The identification of sarcopenia involves screening tests and a comprehensive assessment of muscle mass, strength, and physical function. Clinical approaches aligned with the principles of comprehensive geriatric assessment prioritize patient-centered care. This assessment aids in identifying issues related to activities of daily living, cognition, mood, nutrition, and social support, alongside other aspects. The general approach to factors underlying muscle loss and functional decline in patients with sarcopenia includes managing chronic diseases and evaluating administered medications, with interventions including exercise and nutrition, as well as evolving pharmacological options. Ongoing research targeting pathways, such as myostatin-activin and exercise mimetics, holds promise for pharmacological interventions. In summary, sarcopenia requires a multifaceted approach, acknowledging its complex etiology and tailoring interventions to individual patient needs.

Circulating lumican as a potential biomarker for osteosarcopenia in older adults.

In vitro and animal experiments demonstrated that lumican exerts anabolic effects on bone and muscle by stimulating osteoblastogenesis, suppressing osteoclastogenesis and increasing myogenesis. However, the relationship between circulating lumican and musculoskeletal phenotypes in humans remains unclear. We aimed to analyze the relationship between serum lumican levels and osteosarcopenia in older adults. Blood samples were collected from 134 participants (age: 65 years and older) who underwent comprehensive assessment of bone and muscle phenotypes. Osteoporosis and sarcopenia were diagnosed based on World Health Organization and Asian consensus guidelines, respectively. Osteosarcopenia was defined as the simultaneous presence of osteoporosis and sarcopenia. After adjusting for sex, age, and body mass index, older adults with osteosarcopenia had 20.2 % lower serum lumican levels than those without (P = 0.010). The odds ratio (OR) for osteosarcopenia per standard deviation decrease in serum lumican level was 4.17 (P = 0.003). Consistently, higher serum lumican levels were correlated with higher bone mass at all measured sites (P = 0.004 to 0.045) and higher grip strength (P = 0.023). Furthermore, participants in the lowest tertile (T1) had 7.56-fold higher OR for osteosarcopenia (P = 0.024) than those in the highest lumican tertile (T3). In conclusion, these findings clinically validate previous experimental data showing the musculoskeletal protective effects of lumican and suggest that blood lumican levels could be used as a potential biomarker to assess the risk of not only osteosarcopenia but also osteoporosis or sarcopenia in older adults.

Phenotype validation of the Korean working group on sarcopenia guideline.

BACKGROUND: This study aimed to validate the proposed Korean Working Group on Sarcopenia (KWGS) guideline, which introduces the concept of functional sarcopenia, in older Korean adults. METHODS: Data from the Aging Study of Pyeongchang Rural Area, a longitudinal cohort of community-dwelling older adults, were utilized to compare frailty status and institutionalization-free survival among participants according to sarcopenia status. Based on the KWGS guideline, severe sarcopenia was defined as low muscle mass and strength with slow gait speed; sarcopenia (not severe) was defined as low muscle mass with low muscle strength or slow gait speed; and functional sarcopenia was defined as low muscle strength and slow gait speed without low muscle mass. RESULTS: Among the 1302 participants, 329 (25.3 %) had severe sarcopenia, 147 (11.3 %) had sarcopenia (not severe), and 277 (21.3 %) had functional sarcopenia. Frailty was significantly greater in participants with any phenotype of sarcopenia than in those without sarcopenia. Additionally, participants with functional sarcopenia were frailer than those with sarcopenia (not severe). Furthermore, the rates of institutionalization and mortality were higher in participants with any phenotype of sarcopenia than in those without sarcopenia. There was no statistical difference between the rates of sarcopenia (not severe) and those with functional sarcopenia. These findings remained consistent after adjusting for age and sex. CONCLUSIONS: Each phenotype according to the KWGS guideline was associated with significantly greater frailty and increased risk of institutionalization and mortality. Functional sarcopenia was associated with greater frailty and had comparable prognosis with sarcopenia (not severe).

Higher Plasma Stromal Cell-Derived Factor 1 Is Associated with Lower Risk for Sarcopenia in Older Asian Adults.

BACKGRUOUND: Despite the protective effects of stromal cell-derived factor 1 (SDF-1) in stimulating muscle regeneration shown in experimental research, there is a lack of clinical studies linking circulating SDF-1 concentrations with muscle phenotypes. In order to elucidate the role of SDF-1 as a potential biomarker reflecting human muscle health, we investigated the association of plasma SDF-1 levels with sarcopenia in older adults. METHODS: This cross-sectional study included 97 community-dwelling participants who underwent a comprehensive geriatric assessment at a tertiary hospital in South Korea. Sarcopenia was defined by specific cutoff values applicable to the Asian population, whereas plasma SDF-1 levels were determined using an enzyme immunoassay. RESULTS: After accounting for sex, age, and body mass index, participants with sarcopenia and low muscle mass exhibited plasma SDF-1 levels that were 21.8% and 18.3% lower than those without these conditions, respectively (P=0.008 and P=0.009, respectively). Consistently, higher plasma SDF-1 levels exhibited a significant correlation with higher skeletal muscle mass index (SMI) and gait speed (both P=0.043), and the risk of sarcopenia and low muscle mass decreased by 58% and 55% per standard deviation increase in plasma SDF-1 levels, respectively (P=0.045 and P=0.030, respectively). Furthermore, participants in the highest SDF-1 tertile exhibited significantly higher SMI compared to those in the lowest tertile (P=0.012). CONCLUSION: These findings clinically corroborate earlier experimental discoveries highlighting the muscle anabolic effects of SDF- 1 and support the potential role of circulating SDF-1 as a biomarker reflecting human muscle health in older adults.

The Clinical Frailty Scale as a Risk Assessment Tool for Dysphagia in Older Inpatients: A Cross-Sectional Study.

BACKGROUND: Dysphagia is a common problem with potentially serious consequences including malnutrition, dehydration, pneumonia, and death. However, there are challenges in screening for dysphagia in older adults. We assessed the feasibility of using the Clinical Frailty Scale (CFS) as a risk assessment tool for dysphagia. METHODS: This cross-sectional study was conducted at a tertiary teaching hospital from November 2021 to May 2022 and included 131 older patients (age ≥65 years) admitted to acute wards. We used the Eating Assessment Tool-10 (EAT-10), which is a simple measure for identifying individuals at risk of dysphagia, to assess the relationship between EAT-10 score and frailty status as measured using the CFS. RESULTS: The mean age of the participants was 74.3±6.7 years, and 44.3% were male. Twenty-nine (22.1%) participants had an EAT-10 score ≥3. The CFS was significantly associated with an EAT-10 score ≥3 after adjusting for age and sex (odds ratio=1.48; 95% confidence interval [CI], 1.09-2.02). The CFS was able to classify the presence of an EAT-10 score ≥3 (area under the receiver operating characteristic [ROC] curve=0.650; 95% CI, 0. 544-0.756). The cutoff point for predicting an EAT-10 score ≥3 was a CFS of 5 according to the highest Youden index, with a sensitivity of 82.8% and a specificity of 46.1%. The positive and negative predictive values were 30.4% and 90.4%, respectively. CONCLUSION: The CFS can be used as a tool to screen for the risk of swallowing difficulty in older inpatients to determine clinical management encompassing drug administration routes, nutritional support, prevention of dehydration, and further evaluation of dysphagia.

Comparative Study of the Accuracy of At-Point Clinical Frailty Scale and Morse Fall Scale in Identifying High-Risk Fall Patients among Hospitalized Adults.

BACKGROUND: Falls are a major concern among hospitalized adults, and it is essential to identify high-risk patients to prevent falls. This retrospective cohort study conducted at the Asan Medical Center, Korea, compared the screening abilities of the at-point Clinical Frailty Scale (CFS) and Morse Fall Scale (MFS) to identify patients at high risk for falls among hospitalized adults. METHODS: We assessed the records of at-point CFS, MFS, and fall incidence during hospitalization of 2,028 patients aged 18 or older included in this study. We calculated the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and area under the curve (AUC) for each tool. RESULTS: Twenty-five patients (1.23%) experienced falls during hospitalization. The mean at-point CFS score was significantly higher in those with falls than in those without falls. The mean MFS score did not differ significantly between the two groups. The optimal cutoff points for the at-point CFS and MFS scores were 5 and 45, respectively. At these cutoffs, the at-point CFS demonstrated a sensitivity of 76.0%, specificity of 54.0%, PPV of 2.0%, and NPV of 99.4%, whereas the MFS demonstrated a sensitivity of 60.0%, specificity of 68.1%, PPV of 2.2%, and NPV of 99.4%. The AUC values for the at-point CFS and MFS were 0.68 and 0.63, respectively, with no significant difference (p=0.31). CONCLUSION: The at-point CFS is a valid screening tool for assessing fall risk in hospitalized adults, as it effectively identifies fall risk with a performance similar to that of the MFS.

Enhancement of Non-Linear Deep Learning Model by Adjusting Confounding Variables for Bone Age Estimation in Pediatric Hand X-rays.

In medicine, confounding variables in a generalized linear model are often adjusted; however, these variables have not yet been exploited in a non-linear deep learning model. Sex plays important role in bone age estimation, and non-linear deep learning model reported their performances comparable to human experts. Therefore, we investigate the properties of using confounding variables in a non-linear deep learning model for bone age estimation in pediatric hand X-rays. The RSNA Pediatric Bone Age Challenge (2017) dataset is used to train deep learning models. The RSNA test dataset is used for internal validation, and 227 pediatric hand X-ray images with bone age, chronological age, and sex information from Asan Medical Center (AMC) for external validation. U-Net based autoencoder, U-Net multi-task learning (MTL), and auxiliary-accelerated MTL (AA-MTL) models are chosen. Bone age estimations adjusted by input, output prediction, and without adjusting the confounding variables are compared. Additionally, ablation studies for model size, auxiliary task hierarchy, and multiple tasks are conducted. Correlation and Bland-Altman plots between ground truth and model-predicted bone ages are evaluated. Averaged saliency maps based on image registration are superimposed on representative images according to puberty stage. In the RSNA test dataset, adjusting by input shows the best performances regardless of model size, with mean average errors (MAEs) of 5.740, 5.478, and 5.434 months for the U-Net backbone, U-Net MTL, and AA-MTL models, respectively. However, in the AMC dataset, the AA-MTL model that adjusts the confounding variable by prediction shows the best performance with an MAE of 8.190 months, whereas the other models show the best performances by adjusting the confounding variables by input. Ablation studies of task hierarchy reveal no significant differences in the results of the RSNA dataset. However, predicting the confounding variable in the second encoder layer and estimating bone age in the bottleneck layer shows the best performance in the AMC dataset. Ablations studies of multiple tasks reveal that leveraging confounding variables plays an important role regardless of multiple tasks. To estimate bone age in pediatric X-rays, the clinical setting and balance between model size, task hierarchy, and confounding adjustment method play important roles in performance and generalizability; therefore, proper adjusting methods of confounding variables to train deep learning-based models are required for improved models.

Lack of association between serum myonectin levels and sarcopenia in older Asian adults.

Myonectin is a muscle-secreted factor that helps maintain homeostasis in the body by regulating several functions, including lipid metabolism. Previous studies suggested that myonectin may play a role in muscle health in an autocrine manner, but its impact on human skeletal muscle is still unclear. We aimed to investigate the relationship of serum myonectin levels with sarcopenia and related muscle parameters. We conducted a cross-sectional study of 142 older adults whose muscle mass, grip strength, gait speed, chair stands, and short physical performance battery (SPPB) were evaluated in the geriatric clinic of a tertiary medical center. Sarcopenia was defined based on Asian-specific cutoff values, and circulating myonectin levels were measured using an enzyme immunoassay. Before and after adjusting for age, sex, and body mass index, the serum myonectin level was not significantly different when the patients were stratified by status of sarcopenia, muscle mass, muscle strength, and physical performance. Furthermore, whether given as a continuous variable or divided into quartile groups, the serum myonectin level had no association with the skeletal muscle mass, grip strength, gait speed, chair stand test, or SPPB score. Our findings did not confirm the potential role of myonectin in muscle metabolism observed in experimental research. Thus, serum myonectin levels cannot predict the risk of sarcopenia in older Asian adults.

Height loss as an indicator of ageing through its association with frailty and sarcopenia: An observational cohort study.

BACKGROUND: Height loss is associated with various health-related variables such as cardiovascular disease, osteoporosis, cognitive function, and mortality. We hypothesized that height loss can be used as an indicator of aging, and we assessed whether the degree of height loss for 2 years was associated with frailty and sarcopenia. METHODS: This study was based on a longitudinal cohort, the Pyeongchang Rural Area cohort. The cohort included people aged 65 years or older, ambulatory, and living at home. We divided individuals according to the ratio of height change (height change for 2 years divided by height at 2 years from baseline): HL2 (<-2%), HL1 (-2%--1%), and REF (-1%≤). We compared the frailty index, diagnosis of sarcopenia after 2 years from baseline, and the incidence of a composite outcome (mortality and institutionalization). RESULTS: In total, 59 (6.9%), 116 (13.5%), and 686 (79.7%) were included in the HL2, HL1, and REF groups, respectively. Compared with the REF group, groups HL2 and HL1 had a higher frailty index, and higher risks of sarcopenia and composite outcome. When groups HL2 and HL1 were merged, the merged group had higher frailty index (standardized B, 0.06; p = 0.049), a higher risk of sarcopenia (OR, 2.30; p = 0.006), and a higher risk of composite outcome (HR, 1.78; p = 0.017) after adjusting for age and sex. CONCLUSIONS: Individuals with greater height loss were frailer, more likely to be diagnosed with sarcopenia and had worse outcomes regardless of age and sex.

Incidence of rheumatic diseases during the COVID-19 pandemic in South Korea.

BACKGROUND/AIMS: The recent coronavirus disease 2019 (COVID-19) pandemic has been associated with changes in the epidemiology of not only infectious diseases but also several non-infectious conditions. This study investigated changes in the recorded incidence of various rheumatic diseases during the COVID-19 pandemic. METHODS: The number of patients for each disease from January 2016 to December 2020 was obtained from the Korean Health Insurance Review and Assessment Service database. We compared the incidence of nine rheumatic diseases (seropositive rheumatoid arthritis, systemic lupus erythematosus [SLE], idiopathic inflammatory myositis [IIM], ankylosing spondylitis [AS], systemic sclerosis, Sjögren's syndrome, Behçet's disease [BD], polymyalgia rheumatica, and gout) and hypertensive diseases to control for changes in healthcare utilisation before and after the COVID-19 outbreak. The disease incidence before and after the COVID-19 outbreak was compared using the autoregressive integrated moving average (ARIMA) and quasi- Poisson analyses. RESULTS: Compared with the predicted incidence in 2020 using the ARIMA model, the monthly incidence of SLE, BD, AS, and gout temporarily significantly decreased, whereas other rheumatic diseases and hypertensive diseases were within the 95% confidence interval (CI) of the predicted values in the first half of 2020. In age- and sex-adjusted quasi-Poisson regression analysis, the annual incidences of IIM (rate ratio [RR], 0.473; 95% CI, 0.307 to 0.697), SLE (RR, 0.845; 95% CI, 0.798 to 0.895), and BD (RR, 0.850; 95% CI, 0.796 to 0.906) were significantly decreased compared with those in the previous 4 years. CONCLUSION: The recorded annual incidence of some rheumatic diseases, including IIM, SLE, and BD, decreased during the COVID-19 pandemic.

Geriatric Medicine in South Korea: A Stagnant Reality amidst an Aging Population.

In the face of an ever-increasing wave of an aging population, this paper provides an update on the current status of geriatric medicine in Korea, comparing it with global initiatives and suggesting future directions. Older adults require a multifaceted approach, addressing not only comorbidity management but also unmet complex medical needs, nutrition, and exercise to prevent functional decline. In this regard, the World Health Organization's Integrated Care for Older People guidelines underscore the importance of patient-centered primary care in preventing a decline in intrinsic capacity. Despite these societal needs and the ongoing aging process, the healthcare system in Korea has yet to show significant movement or a shift toward geriatric medicine, further complicated by the absence of a primary care system. We further explore global efforts in establishing age-integrative patient-centered medical systems in Singapore, Australia, Canada, the United Kingdom, and Japan. Additionally, we review the unmet needs and social issues that Korean society is currently facing, and local efforts by both government and a private tertiary hospital in Korea. In conclusion, considering the current situation, we propose that the framework of geriatric medicine should form the foundation of the future healthcare system.

Automated landmark identification for diagnosis of the deformity using a cascade convolutional neural network (FlatNet) on weight-bearing lateral radiographs of the foot.

Landmark detection in flatfoot radiographs is crucial in analyzing foot deformity. Here, we evaluated the accuracy and efficiency of the automated identification of flatfoot landmarks using a newly developed cascade convolutional neural network (CNN) algorithm, Flatfoot Landmarks AnnoTating Network (FlatNet). A total of 1200 consecutive weight-bearing lateral radiographs of the foot were acquired. The first 1050 radiographs were used as the training and tuning, and the following 150 radiographs were used as the test sets, respectively. An expert orthopedic surgeon (A) manually labeled ground truths for twenty-five anatomical landmarks. Two orthopedic surgeons (A and B, each with eight years of clinical experience) and a general physician (GP) independently identified the landmarks of the test sets using the same method. After two weeks, observers B and GP independently identified the landmarks once again using the developed deep learning CNN model (DLm). The X- and Y-coordinates and the mean absolute distance were evaluated. The average differences (mm) from the ground truth were 0.60 ± 0.57, 1.37 ± 1.28, and 1.05 ± 1.23 for the X-coordinate, and 0.46 ± 0.59, 0.97 ± 0.98, and 0.73 ± 0.90 for the Y-coordinate in DLm, B, and GP, respectively. The average differences (mm) from the ground truth were 0.84 ± 0.73, 1.90 ± 1.34, and 1.42 ± 1.40 for the absolute distance in DLm, B, and GP, respectively. Under the guidance of the DLm, the overall differences (mm) from the ground truth were enhanced to 0.87 ± 1.21, 0.69 ± 0.74, and 1.24 ± 1.31 for the X-coordinate, Y-coordinate, and absolute distance, respectively, for observer B. The differences were also enhanced to 0.74 ± 0.73, 0.57 ± 0.63, and 1.04 ± 0.85 for observer GP. The newly developed FlatNet exhibited better accuracy and reliability than the observers. Furthermore, under the FlatNet guidance, the accuracy and reliability of the human observers generally improved.

Association Between Changes in Frailty Index and Clinical Outcomes: An Observational Cohort Study.

Purpose: Although the association between a single assessment of frailty index (FI) and clinical outcomes has been revealed in prior studies, there is a lack of knowledge about the prognostic value of FI at different time points and the changes in repeated measurements of FI. Hence, we sought to determine the clinically meaningful changes in FI and reveal the association with the changes and a composite outcome of mortality and institutionalization. Participants and Methods: This study was based on a longitudinal study of the Pyeongchang Rural Area cohort that included people aged 65 years or older, ambulatory and living at home. Individuals were divided into the worsened group (changes in FI ≥ 0.03 during 2 years) and the stable group (changes in FI < 0.03 during 2 years). The incidence of a composite outcome was compared between the two groups and the relationship was adjusted for age, sex, baseline FI, and follow-up FI. Results: Of the 953 participants, 403 (42.3%) and 550 (57.7%) were included in the worsened group and the stable group, respectively. The worsened group had a significantly higher risk of the composite outcome than the stable group (HR, 2.37 [95% CI, 1.54-3.67]; p < 0.001). Although the higher risk remained significant after adjusting for age, sex, and baseline FI, the statistical significance disappeared after adjusting for follow-up FI (p = 0.614). The aggravation of FI in the worsened group was predominantly due to aggravation of FI domains, such as activities in daily living, cognitive function and mood, and mobility rather than comorbidity burden. Conclusion: Aggravation of FI was associated with a composite outcome regardless of baseline FI, and the association was significantly reflected in the follow-up measurement of FI. The worsening FI was mainly attributable to functional geriatric domains.