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Objectives: Although it is difficult to define the quality of stroke care, acute ischemic stroke (AIS) patients with moderate-to-severe neurological deficits may benefit from thrombectomy-capable hospitals (TCHs) that have a stroke unit, stroke specialists, and a substantial endovascular thrombectomy (EVT) case volume.Methods: From national audit data collected between 2013 and 2016, potential EVT candidates arriving within 24 hours with a baseline National Institutes of Health Stroke Scale score ≥6 were identified. Hospitals were classified as TCHs (≥15 EVT case/y, stroke unit, and stroke specialists), primary stroke hospitals (PSHs) without EVT (PSHs-without-EVT, 0 case/y), and PSHs-with-EVT. Thirty-day and 1-year case-fatality rates (CFRs) were analyzed using random intercept multilevel logistic regression.Results: Out of 35 004 AIS patients, 7954 (22.7%) EVT candidates were included in this study. The average 30-day CFR was 16.3% in PSHs-without-EVT, 14.8% in PSHs-with-EVT, and 11.0% in TCHs. The average 1-year CFR was 37.5% in PSHs-without-EVT, 31.3% in PSHs-with-EVT, and 26.2% in TCHs. In TCHs, a significant reduction was not found in the 30-day CFR (odds ratio [OR], 0.92; 95% confidence interval [CI], 0.76 to 1.12), but was found in the 1-year CFR (OR, 0.84; 95% CI, 0.73 to 0.96).Conclusions: The 1-year CFR was significantly reduced when EVT candidates were treated at TCHs. TCHs are not defined based solely on the number of EVTs, but also based on the presence of a stroke unit and stroke specialists. This supports the need for TCH certification in Korea and suggests that annual EVT case volume could be used to qualify TCHs.

Objectives: This study aimed to determine the associations between income level and stroke incidence in hypertensive patients. We also tried to measure the mediating effect of poor antihypertensive medication adherence through causal mediation analysis. Methods: This study used the National Health Insurance Service National Sample Cohort Data from 2006 to 2015. The study population was newly diagnosed patients with hypertension aged 18 to 80. The associations between the independent-dependent variables, the mediator-dependent variables were confirmed with Cox proportional hazards regression models. In order to verify the mediating effect of poor hypertension medication adherence between income level and stroke occurrence, a weighting approach of causal mediation analysis method was used. Since age was the moderate variable, 18-49 years old and 50-80 years old were stratified. Results: Under 50 years of age, all the other income groups had a significantly higher risk of poor medication adherence than the highincome group. For the patients aged 50 and older, the low-income group and the Medical Aid beneficiaries had a higher risk of poor medication adherence compared to the high-income group. In the patient under 50 years of age, the risk for the stroke incidence of the low-income group and the Medical Aid beneficiaries were higher than those in the high-income group. In the patients aged 50 and older, all the other income groups had a significantly higher risk of incidence of stroke. Causal mediation analysis showed that the mediated effect of poor medication adherence in all groups was not significant. Conclusions: Low income significantly increased poor hypertension medication adherence and the incidence of stroke. The mediated effect of poor medication adherence was not significant.

Objectives: Economic hardship has a serious impact on adolescents’ mental health. The financial impact of the coronavirus disease 2019 (COVID-19) pandemic was more severe for low-income families, and this also impacted adolescents. This study aimed to examine the associations of economic deterioration (ED) caused by the COVID-19 pandemic and low socioeconomic status (SES) with adolescents’ suicidal behaviors.Methods: This study analyzed data from the 2020 Korea Youth Risk Behavior Web-based Survey, which included 54 948 middle and high school students. Odds ratios (ORs) of suicidal ideation, suicidal planning, and suicide attempts related to ED and SES were calculated using multivariable logistic regression. We calculated relative excess risks due to interaction to assess additive interactions.Results: The ORs for suicidal ideation, suicidal planning, and suicide attempts related to combined severe ED and low SES were 3.64 (95% confidence interval [CI], 3.13 to 4.23), 3.88 (95% CI, 3.09 to 4.88), and 4.27 (95% CI, 3.21 to 5.69), respectively.Conclusions: ED and low SES were significantly associated with suicidal behaviors in adolescents. Although no significant additive interaction was found, the ORs related to suicidal ideation, suicidal planning, and suicide attempts were highest among adolescents from low-income families with severe ED. Special attention is needed for this group, considering the increased impact of economic inequality due to the COVID-19 pandemic.

This paper discusses our collaboration work with government officers in the health department of Seoul during the COVID-19 pandemic. First, we focus on short-term forecasting for the number of new confirmed cases and severe cases. Second, we focus on understanding how much of the current infections has been affected by external influx from neighborhood areas or internal transmission within the area. This understanding may be important because it is linked to the government policy determining non-pharmaceutical interventions. To obtain the decomposition of the effect, districts of Seoul should be considered simultaneously, and multivariate time series models are used. Third, we focus on predicting the number of new weekly confirmed cases for each district in Seoul. This detailed prediction may be important to the government policy on resource allocation. We consider an ensemble method to overcome poor prediction performance of simple models. This paper presents the methodological details and analysis results of the study.

BACKGROUND Coronavirus disease 2019 (COVID-19) testing is essential, as it enables early detection and halting the spread of infection throughout the community. Real-time reverse-transcriptase polymerase chain reaction (real-time RT-PCR) testing is the predominant method for detecting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in samples, and the cycle threshold value (Ct value) is used to determine COVID-19 positivity. OBJECTIVE The aim of the present study was to examine time series distribution during the COVID-19 pandemic, using Ct values at the national level in Korea, and analyze the association between Ct values and the time-varying reproduction number (Rt) to discuss the utilization of laboratory-based COVID-19 test results. METHODS We used real-time RT-PCR results collected by the Seegene Medical Foundation from the index case in Korea between February 2020 and January 2022. The distribution of daily Ct values (RdRp/S target) was examined and compared with the daily count of newly diagnosed cases and Rt to determine the usability of Ct values. Moreover, time lag was applied to the daily count of newly diagnosed cases to analyze the association between Ct values and Rt. RESULTS During the COVID-19 pandemic, Ct values declined in general, while viral load increased progressively. After Ct values dropped markedly, the number of newly diagnosed cases rose substantially, and the association analysis confirmed that the daily count of newly diagnosed cases declined with increasing Ct values. The time series trend of the Ct values was also similar to that of Rt, a classic marker that was used as a predictor of pandemic trends; when compared to the actual count of newly diagnosed cases, we found that Ct values could be used to predict new diagnoses earlier than Rt. The fact that the Ct values were more sensitive to a substantial rise of new COVID-19 cases than Rt in the early days of the pandemic also supports this finding. CONCLUSIONS We examined the potential of Ct values as a predictor of new COVID-19 cases in real-time using nationally collected Ct value data. Further, we proposed the use of Ct values as an index reflecting the degree of viral load. The findings of this study can be used to establish indicators with higher predictive power than conventional outbreak predictions.

Background: Anticoagulation is important in atrial fibrillation (AF) patients to reduce the occurrence of thrombotic events. We evaluated the efficacy and safety of percutaneous left atrial appendage occlusion (LAAO) as an alternative to systemic anticoagulation through an indirect comparative analysis.Methods: An indirect comparative analysis of nonvitamin K oral anticoagulants (NOACs) and LAAO was conducted. Comparisons were made using data from four landmark randomized clinical trials (RE-LY, ROCKET-AF, ARISTOTLE, and PROTECT AF). Using warfarin as the common comparator, an indirect comparison was performed using data from each trial, and the relative risk was calculated between NOACs and LAAO.Results: NOACs and LAAO showed similar results for the reduction of stroke and systemic embolism, with a non-statistically significant trend favoring NOACs (hazard ratio [HR], 0.74; 95% confidence interval [CI], 0.37–1.46 for dabigatran; HR, 0.99; 95% CI, 0.50–1.92 for rivaroxaban; HR, 0.89; 95% CI, 0.45–1.74 for apixaban). Significantly fewer major bleeding and procedure-related complications were found in patients treated with apixaban compared with LAAO (HR, 0.45; 95% CI, 0.26–0.75). Cardiovascular death occurred more frequently in patients administered NOACs than in patients with LAAO (HR, 2.28; 95% CI, 1.03–5.10 for dabigatran; HR, 2.41; 95% CI, 1.09–5.42 for rivaroxaban; HR, 2.40; 95% CI, 1.10–5.36 for apixaban). Conclusions: The rate of all-cause death was similar between NOACs and LAAO. Compared with LAAO, NOACs led to a nonsignificant numerical decrease in stroke and embolism in AF patients. Significantly fewer safety events occurred in patients treated with apixaban. LAAO significantly reduced cardiovascular death.

During the coronavirus disease 2019 (COVID-19) pandemic, COVID-19 testing is crucial, as it enables early detection and halting the spread of infection throughout the community. Real-time reverse-transcriptase polymerase chain reaction (Real-time RT-PCR) testing is the predominant method for COVID-19 testing, and the cycle threshold value (Ct value) is used to determine COVID-19 positivity. There are many ongoing studies using Ct value, and the present study aims to examine time series distribution during the pandemic using Ct values at the national level and analyze the association with time-varying reproduction number (Rt) to discuss the utilization of laboratory-based COVID-19 test results. We used Real-time RT-PC results collected by Seegene Medical Foundation from the index case in Korea in February 2020 to January 2022 in Korea. The distribution of daily Ct value ( RdRp/S target) was examined, and it was compared with the daily count of newly diagnosed cases and Rt to determine the usability of Ct values. Moreover, time lag was applied to the daily count of newly diagnosed cases to analyze the association between Ct values and Rt. During the COVID-19 pandemic, Ct values declined in general, while viral load increased progressively. After Ct values dropped markedly, the number of newly diagnosed cases rose substantially, and the association analysis also confirmed that the daily count of newly diagnosed cases declined with increasing Ct values. The time series trend of the Ct values was also similar to that of Rt, a classic marker used as a predictor of the trends of the pandemic, and when compared to the actual count of newly diagnosed cases, Ct values can be used to predict new diagnoses earlier than Rt. The fact that the Ct values were more sensitive to a substantial rise of new COVID-19 cases than Rt was in the early days of the pandemic also support this. We examined the potential of Ct values as a predictor of new COVID-19 cases in real-time using nationally collected Ct value data. Further, we proposed the use of Ct values as an index reflecting the degree of viral load, so the findings of this study can be used as valuable evidence to support public health decisions for response and resource distribution.

Objectives: This study aimed to explore the status of regional variations in acute ischemic stroke (AIS) treatment and investigate the association between the presence of a thrombectomy-capable stroke center (TSC) and the case fatality rate (CFR) of AIS within hospital service areas (HSAs).Methods: This observational cross-sectional study analyzed acute stroke quality assessment program data from 262 hospitals between 2013 and 2016. TSCs were defined according to the criteria of the Joint Commission. In total, 64 HSAs were identified based on the addresses of hospitals. We analyzed the effects of structure factors, process factors, and the presence of a TSC on the CFR of AIS using multivariate logistic regression.Results: Among 262 hospitals, 31 hospitals met the definition of a TSC. Of the 64 HSAs, only 20 had a TSC. At hospitals, the presence of a stroke unit, the presence of stroke specialists, and the rate of endovascular thrombectomy (EVT) treatment were associated with reductions in the CFR. In HSAs, the rate of EVT treatment (odds ratio [OR], 0.98; 95% confidence interval [CI], 0.97 to 0.99) and the presence of a TSC (OR, 0.93; 95% CI, 0.88 to 0.99) significantly reduced the CFR of AIS.Conclusions: The presence of a TSC within an HSA, corresponding to structure and process factors related to the quality of care, contributed significantly to lowering the CFR of AIS. The CFR also declined as the rate of treatment increased. This study highlights the importance of TSCs in the development of an acute stroke care system in Korea.

Varicella is a highly contagious disease caused by the varicella-zoster virus (VZV). Given its tendency to cluster geographically, spatial analyses may provide a better understanding of the pattern of varicella transmission. We investigated the spatial characteristics of varicella in Korea and the risk factors for varicella at a national level. Using national surveillance and demographic data, we examined the spatial distribution of incidence rates and their spatial autocorrelation and calculated Moran's index. Spatial regression analysis was used to identify sociodemographic predictors of varicella incidence at the district level. An increasing tendency in the annual incidence of varicella was observed over a 12-year period (2006-2018), with a surge in 2017. There was a clear positive spatial autocorrelation of the varicella incidence rate during the surveillance period. During 2006-2014, High-High (HH) clusters were mostly confined to the northeast region and neighboring districts. The spatial error model showed that population density had a negative coefficient and childhood percentage, percentage of children under 12 years of age among the total population, had positive coefficient, whereas vaccine coverage was insignificant. The varicella incidence according to geographic region varied with population density, childhood percentage, suggesting the importance of community-level surveillance and monitoring strategies.

The prevalence of overweight and obesity are well known risk factors of atherosclerotic cardiovascular disease (ASCVD). We aimed to examine the association between body mass index (BMI) and ASCVD over a 23-year follow-up in young adults. We also qualified how much of the effects of obesity on ASCVD were mediated through blood pressure, cholesterol and glucose.Data are from the Korean Life Course Health Study, a cohort study of 226,955 Korean young adults aged 20-39. At baseline, the participants undertook routine health assessments where their BMI was measured in 1992-1994; and the metabolic mediators including systolic blood pressure (SBP), fasting serum glucose (FSG), and total cholesterol (TC) were re-measured in 2002-2004. The main outcomes of the study include incident events of ischemic heart disease (IHD), stroke, and ASCVD between 2005 and 2015. Cox proportional model was used to calculate adjusted hazard ratio (HR) for ASCVD.In both men and women, the direct effect of BMI on ASCVD was greater than the indirect effect. The percentage of excess HR of BMI mediated by all of the metabolic mediators including SBP, FSG, and TC was 45.7% for stroke and 18.7% for IHD in men and 27.5% for stroke and 17.6% for IHD in women.High BMI in young adults increases the risk of metabolic mediators in their middle age, and metabolic mediators explain the adverse effects of high BMI on stroke risk than IHD risk.

Abdominal obesity, which is a strong indicator of cardiometabolic risk, is widely evaluated using waist circumference (WC) and waist-height ratio (WHtR). In Korea, the reference values for WC for children and adolescents were published in 2007 and need to be revised. Moreover, there is no reference for WHtR. The aim of this study was to establish new reference values for WC and WHtR in Korean children and adolescents.Data of 20,033 subjects from the Korea National Health and Nutrition Examination Survey (2007-2019) were used. Tables for reference values and the graphs of smoothed percentile curves of WC and WHtR for children and adolescents aged 2-18 years by sex were generated using the LMS method and locally estimated scatterplot smoothing regression analysis after removing extreme values.Sex-specific reference tables and percentile curves for WC and WHtR were developed. In the new WC curves, the 10th, 50th, and 90th percentile lines were lower than the corresponding lines of the 2007 reference for both sexes. The WHtR curves showed sex-specific differences, although they demonstrated a relative plateau among those aged ≥10 years in both sexes. In the logistic regression analysis, the WC and WHtR z-scores showed higher odds ratios for predicting cardiometabolic risk factors than the body mass index z-score.New WC and WHtR reference values for Korean children and adolescents aged 2-18 years were developed using the latest statistical methods. These references will help monitor and track WC and WHtR for evaluating abdominal obesity among at-risk children and adolescents in Korea.

To provide the clinical characteristics, prognostic factors, and 5-year relative survival rates of lung cancer diagnosed in 2015.The demographic risk factors of lung cancer were calculated using the KALC-R (Korean Association of Lung cancer Registry) cohort in 2015, with survival follow-up until December 31, 2020. The 5-year relative survival rates were estimated using Ederer II methods, and the general population data used the death rate adjusted for sex and age published by the Korea Statistical Information Service from 2015 to 2020.We enrolled 2,657 patients with lung cancer who were diagnosed in South Korea in 2015. Of all patients, 2,098 (79.0%) were diagnosed with NSCLC and 345 (13.0%) were diagnosed with SCLC, respectively. Old age, poor performance status, and advanced clinical stage were independent risk factors for both NSCLC and SCLC. In addition, the 5-year relative survival rate declined with advanced stage in both NSCLC (82%, 59%, 16%, 10% as the stage progressed) and SCLC (16%, 4% as the stage progressed). In patients with stage IV adenocarcinoma, the 5-year relative survival rate was higher in the presence of EGFR mutation (19% vs 11%) or ALK translocation (38% vs 11%).In this Korean nationwide survey, the 5-year relative survival rates of NSCLC were 82% at stage I, 59% at stage II, 16% at stage III, and 10% at stage IV, and the 5-year relative survival rates of SCLC were 16% in cases with limited disease, and 4% in cases with extensive disease.

Tacrolimus is a key drug in kidney transplantation (KT) with a narrow therapeutic index. The association between the tacrolimus metabolism rate and KT outcomes have not been investigated in large-scale multi-center studies. The Korean Organ Transplantation Registry (KOTRY) datasets were used. A total of 3456 KT recipients were analyzed. The tacrolimus metabolism rate was defined as blood trough concentration of tacrolimus (C0 ) divided by the daily dose (D). The patients were grouped into fast, intermediate, or slow metabolizers by the C0 /D measured 6 months after transplantation. The slow metabolism group was associated with a 2.7 ml/min/1.73 m2 higher adjusted estimated glomerular filtration rate (eGFR) at 6 months [95% confidence interval (C.I.) 1.2-4.3, P = 0.001], less acute rejection (AR) within 6 months [Odds ratio (OR) 0.744, 95% C.I. 0.585-0.947, P = 0.016], and less interstitial fibrosis and tubular atrophy [OR 0.606, 95% C.I. 0.390-0.940, P = 0.025]. Fast tacrolimus metabolism affected the 6-month post-KT eGFR through mediation of AR [natural indirect effect (NIE) -0.434, 95% C.I. -0.856 to -0.012, P = 0.044) and delayed graft function (DGF; NIE -0.119, 95% C.I. -0.231 to -0.007, P = 0.038). Slow tacrolimus metabolism was associated with better post-KT eGFR. AR and DGF were found to be significant mediators.

The surge in coronavirus disease 2019 (COVID-19) cases overwhelmed the health system in the Republic of Korea.To help health-care workers prioritize treatment for patients with more severe disease and to decrease the burden on health systems caused by COVID-19, the government established a system to classify disease severity. Health-care staff in city- and provincial-level patient management teams classified the patients into the different categories according to the patients' pulse, systolic blood pressure, respiratory rate, body temperature and level of consciousness. Patients categorized as having moderate, severe and very severe disease were promptly assigned to beds or negative-pressure isolation rooms for hospital treatment, while patients with mild symptoms were monitored in 16 designated facilities across the country.The case fatality rate was higher in the city of Daegu and the Gyeongsangbuk-do province (1.6%; 124/7756) than the rest of the country (0.5%; 7/1485).From 25 February to 26 March 2020, the ratio of negative-pressure isolation rooms per COVID-19 patient was below 0.15 in the city of Daegu and the Gyeongsangbuk-do province. In the rest of the country, this ratio decreased from 5.56 to 0.63 during the same period. Before the classification system was in place, eight (15.7%) out of the 51 deaths occurred at home or during transfer from home to health-care institutions.Categorizing patients according to their disease severity should be a prioritized measure to ease the burden on health systems and reduce the case fatality rate.La flambée de cas de maladie à coronavirus 2019 (COVID-19) a submergé le système de santé en République de Corée.Afin d'aider le personnel soignant à mieux organiser la prise en charge des patients présentant une forme sévère de la maladie et d'alléger le fardeau que la COVID-19 fait peser sur le secteur des soins de santé, le gouvernement a établi un système de classification du degré de gravité. Des professionnels de la santé appartenant aux équipes de gestion des patients à l'échelle municipale et provinciale ont divisé les patients en différentes catégories selon leur rythme cardiaque, leur tension artérielle systolique, leur fréquence respiratoire, leur température corporelle et leur état de conscience. Les patients considérés comme souffrant d'une forme modérée, grave et extrêmement grave de la maladie ont rapidement été placés dans des lits ou des chambres d'isolement à pression négative pour recevoir un traitement hospitalier, tandis que les patients présentant de légers symptômes étaient surveillés dans 16 centres prévus à cet effet, disséminés dans le pays.Le taux de létalité s'est révélé plus élevé dans la ville de Daegu et la province de Gyeongsang du Nord (1,6%; 124/7756) que dans le reste du pays (0,5%; 7/1485).Entre le 25 février et le 26 mars 2020, la proportion de chambres d'isolement à pression négative par patient COVID-19 était inférieure à 0,15 dans la ville de Daegu et la province de Gyeongsang du Nord. Dans le reste du pays, cette proportion a diminué de 5,56 à 0,63 durant la même période. Avant l'instauration du système de classification, huit (15,7%) des 51 décès sont survenus à domicile ou lors du transfert vers les établissements de soins de santé.Il faut privilégier la répartition des patients selon le degré de gravité de la maladie pour décharger le système de santé et réduire le taux de létalité.El aumento de los casos de la enfermedad por coronavirus de 2019 (COVID-19) saturó el sistema sanitario de la República de Corea.Para ayudar a los profesionales sanitarios a dar prioridad al tratamiento de los pacientes con enfermedades más graves y para disminuir la carga que supone para los sistemas sanitarios debido a la COVID-19, el gobierno estableció un sistema de clasificación del grado de gravedad de las enfermedades. El personal sanitario de los equipos de gestión de los pacientes a nivel de ciudad y de provincia clasificó a los pacientes en las diferentes categorías según el pulso, la tensión arterial sistólica, la frecuencia respiratoria, la temperatura corporal y el nivel de conciencia de los pacientes. Los pacientes clasificados como con enfermedad moderada, grave y muy grave fueron asignados de inmediato a camas o salas de aislamiento con presión negativa para su tratamiento hospitalario, mientras que los pacientes con síntomas leves fueron supervisados en 16 instalaciones designadas en todo el país.La tasa de letalidad fue mayor en la ciudad de Daegu y en la provincia de Gyeongsangbuk-do (1,6 %; 124/7756) que en el resto del país (0,5 %; 7/1485).Del 25 de febrero al 26 de marzo de 2020, el cociente de las salas de aislamiento con presión negativa por cada paciente con la COVID-19 fue inferior a 0,15 en la ciudad de Daegu y en la provincia de Gyeongsangbuk-do. En el resto del país, este cociente disminuyó de 5,56 a 0,63 durante el mismo periodo. Antes de que se estableciera el sistema de clasificación, ocho (15,7 %) de las 51 muertes ocurrieron en el hogar o durante el traslado del hogar a las instituciones sanitarias.La clasificación de los pacientes según la gravedad de su enfermedad debería ser una medida prioritaria para aliviar la carga del sistema sanitario y reducir la tasa de letalidad.المشكلة سيطر الارتفاع في حالات الإصابة بمرض فيروس كورونا (كوفيد 19) على النظام الصحي في جمهورية كوريا. الأسلوب في سبيل مساعدة العاملين في مجال الرعاية الصحية في منح أولوية العلاج للمرضى الذين يعانون من شدة أكثر للمرض، ولتقليل العبء على النظم الصحية الناجم عن كوفيد 19، قامت الحكومة بإنشاء نظام لتصنيف شدة المرض. قام موظفو الرعاية الصحية، في فرق إدارة المرضى على مستوى المدينة والمقاطعة، بتصنيف المرضى إلى فئات مختلفة وفقًا لنبض المرضى، وضغط الدم الانقباضي، ومعدل التنفس، ودرجة حرارة الجسم، ومستوى الوعي. المرضى الذين تم تصنيفهم على أنهم يعانون من أعراض معتدلة، وشديدة، وشديدة للغاية، تم على وجه السرعة منحهم أسرّة، أو غرف عزل الضغط السلبي للعلاج في المستشفى، بينما خضع المرضى الذين يعانون من أعراض خفيفة للمراقبة في 16 منشأة مخصصة في جميع أنحاء البلاد. المواقع المحلية كان معدل الوفيات الحالات أعلى في مدينة دايجو، ومقاطعة جيونج سانج بوك دو (1.6%؛ 124/7756)، مقارنة ببقية البلاد (0.5%؛ 7/1485). التغيّرات ذات الصلة في الفترة من 25 فبراير/شباط إلى 26 مارس/آذار 2020، كانت نسبة غرف عزل الضغط السلبي لكل مريض مصاب بكوفيد 19 أقل من 0.15 في مدينة دايجو ومقاطعة جيونج سانج بوك دو. وفي باقي أنحاء البلاد، انخفضت هذه النسبة من 5.56 إلى 0.63 خلال نفس الفترة. قبل وضع نظام التصنيف قيد التنفيذ، حدثت ثماني حالات وفاة (15.7%) من أصل 51 حالة وفاة في المنزل، أو أثناء النقل من المنزل إلى مؤسسات الرعاية الصحية. الدروس المستفادة إن تصنيف المرضى وفقًا لشدة مرضهم يجب أن يكون إجراءً له الأولوية لتخفيف العبء على النظام الصحي وتقليل معدل وفيات الحالات.2019 冠状病毒病（新型冠状病毒肺炎）病例激增导致韩国卫生系统不堪重负。.为帮助医护人员优先选择治疗病情更严重的患者，并减轻新型冠状病毒肺炎给卫生系统带来的负担，政府设立了疾病严重程度分级体系。省级和市级患者诊治团队的医护人员依据患者脉搏、收缩压、呼吸频率、体温和意识程度将患者分成不同的级别。中症、重症、危重症患者将被立即送至病房或负压隔离病房以接受住院治疗，轻症患者则会被送往全国 16 家指定机构进行监控。.大邱市和庆尚北道省的病死率 (1.6%; 124/7756) 高于全国其他地区 (0.5%; 7/1485)。.2020 年 2 月 25 日至 3 月 26 日期间， 大邱市和庆尚北道省每名新型冠状病毒肺炎患者的负压隔离病房使用率低于 0.15。同一期间，该国其他地区的该比率从 5.56 降至 0.63。实施分级体系之前， 51 例死亡病例中有 8 例 (15.7%) 发生于家中或从家转移至医疗机构的路上。.应优先根据患者危重程度对其归类，从而减轻卫生系统的负担并降低病死率。.Всплеск случаев заболевания коронавирусом 2019 г. (COVID-19) поразил систему здравоохранения Республики Корея.Правительство создало систему классификации тяжести заболевания, чтобы помочь работникам здравоохранения установить приоритетность лечения пациентов с более тяжелыми заболеваниями и снизить нагрузку на системы здравоохранения, обусловленную COVID-19. Персонал сферы здравоохранения в группах по ведению пациентов на уровне городов и провинций классифицировал пациентов по различным категориям в зависимости от пульса пациента, систолического артериального давления, частоты дыхания, температуры тела и уровня сознания. Пациенты, у которых тяжесть заболевания была классифицирована как умеренная, тяжелая и очень тяжелая, были незамедлительно распределены по койкам или изоляторам с отрицательным давлением для госпитализации, в то время как пациенты с легкими симптомами находились под наблюдением в 16 назначенных учреждениях по всей стране.Показатели летальности были выше в городе Тэгу и провинции Кёнсан-Пукто (1,6%; 124/7756), чем в остальной части страны (0,5%; 7/1485).С 25 февраля по 26 марта 2020 года соотношение изоляторов с отрицательным давлением на пациента с COVID-19 было ниже показателя в 0,15 в городе Тэгу и провинции Кёнсан-Пукто. В остальной части страны показатель указанного соотношения за тот же период снизился с 5,56 до 0,63. До введения в действие системы классификации 8 случаев смерти (15,7%) из 51 происходили дома или во время транспортировки пациентов из их домов в медицинские учреждения.Классификация пациентов по степени тяжести заболевания должна стать приоритетной мерой для облегчения нагрузки на систему здравоохранения и снижения показателей летальности.

The increasing incidence of diabetes among young adults is a disease burden; however, the effects of early-onset diabetes, prediabetes and glycaemic recovery on CVD or mortality remain unclear. We aimed to investigate the association of these factors with 10 year all-cause mortality, CVD mortality and CVD incidence in Korean young adults.This large and longitudinal cohort study included data from the Korean National Health Insurance Service-National Health Information Database; 2,502,375 young adults aged 20-39 years without diabetes mellitus and CVD at baseline were included. Glycaemic status was measured twice, first in 2002-2003 and second in 2004-2005. Changes in fasting glucose levels were evaluated according to fasting glucose status: normal fasting glucose (NFG;5.5 mmol/l), impaired fasting glucose (IFG; 5.5-6.9 mmol/l), and diabetic fasting glucose (DFG; ≥7.0 mmol/l). Primary outcomes were all-cause and CVD mortality risk. The secondary outcome was incidence of CVD, including acute myocardial infarction and stroke. All outcomes arose from the 10 year follow-up period 1 Jan 2006 to 31 December 2015.Individuals with NFG at baseline, who were subsequently newly diagnosed with diabetes and prediabetes (IFG), had increased all-cause mortality (HR [95% CI] 1.60 [1.44, 1.78] and 1.13 [1.09, 1.18], respectively) and CVD incidence (1.13 [1.05, 1.23] and 1.04 [1.01, 1.07], respectively). In those with DFG at baseline, early recovery to NFG and IFG was associated with decreased all-cause mortality (0.57 [0.46, 0.70] and 0.65 [0.53, 0.81], respectively) and CVD incidence (0.70 [0.60, 0.81] and 0.78 [0.66, 0.91], respectively). Among patients with IFG at baseline, early recovery to NFG was associated with decreased CVD mortality (0.74 [0.59, 0.93]).Early-onset diabetes or prediabetes increased CVD risks and all-cause mortality after the 10 year follow-up. Furthermore, recovery of hyperglycaemia could reduce the subsequent 10 year risk for CVD incidence and all-cause mortality. Graphical abstract.

Emerging evidence supports an association between heat exposure and acute kidney injury (AKI). However, there is a paucity of studies on the association between cold exposure and AKI.We aimed to investigate the associations of cold exposure with hospital admission and mortality due to AKI and to explore whether these associations were influenced by age and sex.Information on daily counts of hospital admission and mortality due to AKI in 16 regions of Korea during the cold seasons (2010-2019) was obtained from the National Health Insurance Service (a single national insurer providing universal health coverage) and Statistics Korea. Daily mean temperature and relative humidity were calculated from hourly data obtained from 94 monitoring systems operated by the Korean Meteorological Administration. Associations of low temperatures (10th percentile of daily mean temperature) and cold spells (≥2 consecutive days with5th percentile of daily mean temperature) up to 21 days with AKI were estimated using quasi-Poisson regression models adjusted for potential confounders (e.g., relative humidity and air pollutants) with distributed lag models and univariate meta-regression models.Low temperatures were associated with hospital admission due to AKI [relative risk (RR) = 1.12, 95 % confidence interval (CI): 1.09, 1.16]. Cold spells were associated with hospital admission (RR = 1.87, 95 % CI: 1.46, 2.39) and mortality due to AKI (RR = 4.84, 95 % CI: 1.30, 17.98). These associations were stronger among individuals aged ≥65 years than among those aged65 years.Our results underscore the need for the general population, particularly the elderly, physicians, and other healthcare providers to be more vigilant to cold exposure, given the risk of AKI. Government agencies need to develop specific strategies for the prevention and early detection of cold exposure-related AKI.

Susceptible-exposed-infectious-recovered (SEIR) models were applied to assess the effectiveness of non-pharmaceutical interventions (NPIs) and to study the dynamic behavior of the COVID-19 pandemic. Recently, SEIR models have evolved to address the change of human mobility by some NPIs for predicting the new confirmed cases. However, the models have serious limitations when applied to Seoul. Seoul has two representative quarantine policies, i.e. social distancing and the ban on gatherings. Effects of the two policies need to be reflected in different functional forms in the model because changes in human mobility do not fully reflect the ban on gatherings. Thus we propose a modified SEIR model to assess the effectiveness of social distancing, ban on gatherings and vaccination strategies. The application of the modified SEIR model was illustrated by comparing the model output with real data.

ImportanceEvidence linking low-carbohydrate diets (LCDs) to mortality is limited among multiethnic populations.ObjectiveTo evaluate the association between LCDs and mortality by race and ethnicity.Design, Setting, and ParticipantsThe Multi-Ethnic Study of Atherosclerosis is a large, population-based prospective cohort study of adults aged 45 to 84 years recruited from 6 US communities. A total of 6109 participants without baseline cardiovascular disease were included in this analysis. Baseline data were collected from July 2000 to August 2002, with follow-up completed by December 2017. The data were analyzed between May 2021 and April 2022.ExposuresFood frequency questionnaires were used to assess dietary intake. From these data, overall LCD scores were calculated from the percentages of energy intake from carbohydrates, fats, and proteins. Animal-based (emphasizing saturated fat and animal protein) and vegetable-based (emphasizing monounsaturated fat and vegetable protein) LCD scores were also calculated.Main Outcomes and MeasuresAll-cause and cause-specific mortality over a median follow-up of 15.9 years (IQR, 14.3-16.6 years).ResultsAmong the 6109 participants (mean [SD] age, 62.3 [10.3] years; 3190 women [52.2%]; 1623 African American [26.6%], 701 Chinese American [11.5%], 1350 Hispanic [22.1%], and 2435 non-Hispanic White [39.8%]), there were 1391 deaths. Overall, LCD scores were not associated with mortality, but when analyses were stratified by race and ethnicity, a lower risk of all-cause and non-CV mortality was observed among Hispanic participants with moderate carbohydrate intake. Specifically, the hazard ratios for total mortality for overall LCD scores were 0.58 (95% CI, 0.40-0.84) for quintile 2, 0.67 (95% CI, 0.45-0.98) for quintile 3, 0.60 (95% CI, 0.41-0.87) for quintile 4, and 0.83 (95% CI, 0.57-1.21) for quintile 5, with quintile 1 as the reference group. A similar association was observed for animal-based (but not vegetable-based) LCD scores. In contrast, no significant associations were found between LCD scores and mortality risk in the other racial and ethnic groups.Conclusions and RelevanceIn this cohort study of multiethnic US adults, LCD score was not associated with mortality in the whole population. However, moderate carbohydrate intake was associated with a lower risk of mortality among Hispanic participants. These findings suggest that the association between carbohydrate intake and mortality may differ according to race and ethnicity. Dietary guidelines considering these differences may be necessary.

Background: Patients undergoing hemodialysis are susceptible to sarcopenia. As intracellular reservoirs of water, skeletal muscles are important contributors to intradialytic hypotension. This study was designed to determine the role of skeletal muscle mass in intradialytic hypotension. Methods: In a cross-sectional study, the body composition of 177 patients was measured immediately after hemodialysis using bioelectrical impedance analysis. The parameters measured were skeletal muscle mass, intracellular and extracellular water contents, total body water, and cell-membrane functionality (in phase angle at 50 kHz). Data from laboratory tests, chest radiography, measurements of handgrip strength and mid-arm circumference, and questionnaires were collected. The main outcome was intradialytic hypotension, defined as more than two episodes of hypotension (systolic blood pressure of

Although obesity has been proven as a risk factor of metabolic and cardiovascular diseases, there have been few studies addressing the association between obesity and cerebral white matter hyperintensity (WMH) volume with controversial findings. In this study, we evaluated the relationship between abdominal fat distribution and WMH volume in a neurologically healthy population. We performed an observational study in a consecutive series of subjects who were examined during voluntary health check-ups between January 2006 and December 2013. We directly measured both visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) using abdominal computed tomography. The WMH volumes were also recorded quantitatively. A total of 2504 subjects were included in this study. In multivariate analysis, the relationship between SAT and WMH volume remained significant (β = −0.170, standard error [SE] = 0.065, P = .006) after adjusting for confounding factors. The protective effects of SAT on the WMH volume were more prominent in female participants (β = −0.295, SE = 0.138, P = .033) and in severely obese participants (β = −0.358, SE = 0.167, P = .033). Conclusively, we demonstrated a negative association between SAT and WMH volume in a healthy population.

Climate change is predicted to increase the frequency, intensity, and duration of extreme cold events in the mid-latitudes. However, although diabetes is one of the most critical metabolic diseases due to its high and increasing prevalence worldwide, few studies have investigated the short-term association between cold exposure and diabetes-related outcomes.The aim of this study was to investigate the associations between cold spells and their characteristics (intensity, duration, and seasonal timing) and hospital admission and mortality due to diabetes.This study used claims data from the National Health Insurance Service and cause-specific mortality data from Statistics Korea (2010-2019). Cold spells were defined as ≥2 consecutive days with a daily mean temperature lower than the region-specific 5th percentile during the cold season (November-March). Quasi-Poisson regressions combined with distributed lag models were used to assess the associations between exposures and outcomes in 16 regions across the Republic of Korea. Meta-analyses were conducted to pool the region-specific estimates.Exposure to cold spells was associated with an increased risk of hospital admission [relative risk (RR) = 1.45, 95% confidence interval (CI): 1.26, 1.66] and mortality (RR = 2.02, 95% CI: 1.37, 2.99) due to diabetes. The association between cold spells and hospital admission due to diabetes was stronger for cold spells that were more intense, longer, and occurred later during the cold season. The association between cold spells and diabetes-related mortality was stronger for more intense and longer cold spells.This study emphasizes the importance of developing effective interventions against cold spells, including education on the dangers of cold spells and early alarm systems. Further studies are needed to create real-world interventions and evaluate their effectiveness in improving diabetes-related outcomes.

BACKGROUND Self-management of lifestyle and cardiovascular disease risk factors is challenging in older patients with coronary heart disease (CHD). SMS text messaging could be a potential support tool for self-management and the most affordable and accessible method through a mobile phone. High-quality evidence had been lacking, and previous studies evaluated the effects of SMS text messaging on the subjective measures of short-term outcomes. Recently, a large-sized randomized controlled trial in Australia reported promising findings on the objective measures upon 6-month follow-up. However, an examination of the effectiveness of such interventions in an Asian population with unique demographic characteristics would be worthwhile. OBJECTIVE This study examined the effectiveness of a 1-way SMS text messaging program to modify the lifestyle and cardiovascular disease risk factors of patients who underwent the first percutaneous coronary intervention (PCI). METHODS A parallel, single-blinded, 1:1 random allocation clinical trial was conducted with 879 patients treated through PCI. They were recruited during hospital admission from April 2017 to May 2020 at 2 university hospitals in the Republic of Korea. In addition to standard care, the intervention group received access to a supporting website and 4 SMS text messages per week for 6 months regarding a healthy diet, physical activity, smoking cessation, and cardiovascular health. Random allocation upon study enrollment and SMS text messaging after hospital discharge were performed automatically using a computer program. The coprimary outcomes were low-density-lipoprotein cholesterol (LDL-C), systolic blood pressure (SBP), and BMI. The secondary outcomes were change in lifestyle and adherence to the recommended health behaviors. RESULTS Of the eligible population, 440 and 439 patients who underwent PCI were assigned to the intervention and control groups, respectively. The 1-way SMS text messaging program significantly enhanced physical activity (P=.02), healthy diet (PP CONCLUSIONS Lifestyle-focused SMS text messages were effective in the self-management of a healthy diet, exercise, and medication adherence, but their influence on the physiological measures was not significant. One-way SMS text messages can be used as an affordable adjuvant method for lifestyle modification to help prevent the recurrence of cardiovascular disease. CLINICALTRIAL Clinical Research Information Service (CRiS) KCT0005087; https://cris.nih.go.kr/cris/search/detailSearch.do/19282

Background The coronavirus disease 2019 (COVID-19) has taken millions of lives and disrupted living standards at individual, societal, and worldwide levels, causing serious consequences globally. Understanding its epidemic curve and spatio-temporal dynamics is crucial for the development of effective public health plans and responses and the allocation of resources. Thus, we conducted this study to assess the epidemiological dynamics and spatio-temporal patterns of the COVID-19 pandemic in Rwanda. Methods Using the surveillance package in R software version 4.0.2, we implemented endemic-epidemic multivariate time series models for infectious diseases to analyze COVID-19 data reported by Rwanda Biomedical Center under the Ministry of Health from March 15, 2020 to January 15, 2021. Results The COVID-19 pandemic occurred in two waves in Rwanda and showed a heterogenous spatial distribution across districts. The Rwandan government responded effectively and efficiently through the implementation of various health measures and intervention policies to drastically reduce the transmission of the disease. Analysis of the three components of the model showed that the most affected districts displayed epidemic components within the area, whereas the effect of epidemic components from spatial neighbors were experienced by the districts that surround the most affected districts. The infection followed the disease endemic trend in other districts. Conclusion The epidemiological and spatio-temporal dynamics of COVID-19 in Rwanda show that the implementation of measures and interventions contributed significantly to the decrease in COVID-19 transmission within and between districts. This accentuates the critical call for continued intra- and inter- organization and community engagement nationwide to ensure effective and efficient response to the pandemic.

Background To validate a stratification method using an inverse of treatment decision rules that can classify non-small cell lung cancer (NSCLC) patients in real-world treatment records.Methods (1) To validate the index classifier against the TNM 7th edition, we analyzed electronic health records (EHRs) of NSCLC patients diagnosed from 2011 to 2015 in a tertiary referral hospital in Seoul, Korea. Predictive accuracy, stage-specific sensitivity, specificity, positive predictive value, negative predictive value, F1 score, and c-statistic were measured.(2) To apply the index classifier in an administrative database, we analyzed NSCLC patients in Korean National Health Insurance Database, 2002-2013. Differential survival rates among the classes were examined with the log-rank test, and class-specific survival rates were compared with the reference survival rates.Results (1) In the validation study (N =1,375), the overall accuracy was 93.8% (95% CI: 92.5%-95.0%). Stage-specific c-statistic was the highest for stage I (0.97, 95% CI: 0.96-0.98) and the lowest for stage III (0.82, 95% CI: 0.77-0.87).(2) In the application study (N = 71,593), the index classifier showed a tendency for differentiating survival probabilities among classes. Compared to the reference TNM survival rates, the index classification under-estimated the survival probability for stages IA, IIIB, and IV, and over-estimated it for stages IIA and IIB.Conclusion The inverse of the treatment decision rules has a potential to supplement a routinely collected database with information encoded in the treatment decision rules to classify NSCLC patients. It requires further validation and replication in multiple clinical settings.

Background To validate a stratification method using an inverse of treatment decision rules that can classify non-small cell lung cancer (NSCLC) patients in real-world treatment records. Methods (1) To validate the index classifier against the TNM 7th edition, we analyzed electronic health records of NSCLC patients diagnosed from 2011 to 2015 in a tertiary referral hospital in Seoul, Korea. Predictive accuracy, stage-specific sensitivity, specificity, positive predictive value, negative predictive value, F1 score, and c-statistic were measured. (2) To apply the index classifier in an administrative database, we analyzed NSCLC patients in Korean National Health Insurance Database, 2002–2013. Differential survival rates among the classes were examined with the log-rank test, and class-specific survival rates were compared with the reference survival rates. Results (1) In the validation study (N = 1375), the overall accuracy was 93.8% (95% CI: 92.5–95.0%). Stage-specific c-statistic was the highest for stage I (0.97, 95% CI: 0.96–0.98) and the lowest for stage III (0.82, 95% CI: 0.77–0.87). (2) In the application study (N = 71,593), the index classifier showed a tendency for differentiating survival probabilities among classes. Compared to the reference TNM survival rates, the index classification under-estimated the survival probability for stages IA, IIIB, and IV, and over-estimated it for stages IIA and IIB. Conclusion The inverse of the treatment decision rules has a potential to supplement a routinely collected database with information encoded in the treatment decision rules to classify NSCLC patients. It requires further validation and replication in multiple clinical settings.

ObjectivesTo determine the impact of restrictions on mobility on reducing transmission of COVID-19.DesignDaily incidence rates lagged by 14 days were regressed on mobility changes using LOESS regression and logit regression between the day of the 100th case in each country to August 31, 2020.Setting34 OECD countries plus Singapore and Taiwan.ParticipantsGoogle mobility data were obtained from people who turned on mobile device-based global positioning system (GPS) and agreed to share their anonymized position information with Google.InterventionsWe examined the association of COVID-19 incidence rates with mobility changes, defined as changes in categories of domestic location, against a pre-pandemic baseline, using country-specific daily incidence data on newly confirmed COVID-19 cases and mobility data.ResultsIn two thirds of examined countries, reductions of up to 40% in commuting mobility (to workplaces, transit stations, retailers, and recreation) were associated with decreased COVID-19 incidence, more so early in the pandemic. However, these decreases plateaued as mobility remained low or decreased further. We found smaller or negligible associations between mobility restriction and incidence rates in the late phase in most countries.ConclusionMild to moderate degrees of mobility restriction in most countries were associated with reduced incidence rates of COVID-19 that appear to attenuate over time, while some countries exhibited no effect of such restrictions. More detailed research is needed to precisely understand the benefits and limitations of mobility restrictions as part of the public health response to the COVID-19 pandemic.WHAT IS ALREADY KNOWN ON THIS TOPICSince SARS-CoV-2 became a pandemic, restrictions on mobility such as limitations on travel and closure of offices, restaurants, and shops have been imposed in an unprecedented way in both scale and scope to prevent the spread of COVID-19 in the absence of effective treatment options or a vaccine. Although mobility restriction has also brought about tremendous costs such as negative economic growth and other collateral impacts on health such as increased morbidity and mortality from lack of access to other essential health services, little evidence exists on the effectiveness of mobility restriction for the prevention of disease transmission. A search of PUBMED and Google Scholar for publications on this topic through Sep 20, 2020 revealed that most of the evidence on the effectiveness of physical distancing comes from mathematical modeling studies using a variety of assumptions. One study investigated only the combined effect of several interventions, including physical distancing, among SARS-CoV-2 infected patients.WHAT THIS STUDY ADDSThis is the first study to investigate the association between change in mobility and incidence of COVID-19 globally using real-time measures of mobility at the population level. For this, we used Google Global Mobility data and the daily incidence of COVID-19 for 36 countries from the day of 100thcase detection through August 31, 2020. Our findings from LOESS regression show that in two-thirds of countries, reductions of up to 40% in commuting mobility were associated with decreased COVID-19 incidence, more so early in the pandemic. This decrease, however, plateaued as mobility decreased further. We found that associations between mobility restriction and incidence became smaller or negligible in the late phase of the pandemic in most countries. The reduced incidence rate of COVID-19 cases with a mild to moderate degree of mobility restriction in most countries suggests some value to limited mobility restriction in early phases of epidemic mitigation. The lack of impact in some others, however, suggests further research is needed to confirm these findings and determine the distinguishing factors for when mobility restrictions are helpful in decreasing viral transmission. Governments should carefully consider the level and period of mobility restriction necessary to achieve the desired benefits and minimize harm.

BACKGROUND Concern regarding the reliability and accuracy of the health-related information provided by online newspaper articles has increased. Numerous criteria and items have been proposed and published regarding the quality assessment of online information, but there is no standard quality assessment tool available for online newspapers. OBJECTIVE This study aimed to develop the Health Information Quality Assessment Tool (HIQUAL) for online newspaper articles. METHODS We reviewed previous health information quality assessment tools and related studies and accordingly developed and customized new criteria. The interrater agreement for the new assessment tool was assessed for 3 newspaper articles on different subjects (colorectal cancer, obesity genetic testing, and hypertension diagnostic criteria) using the Fleiss κ and Gwet agreement coefficient. To compare the quality scores generated by each pair of tools, convergent validity was measured using the Kendall τ ranked correlation. RESULTS Overall, the HIQUAL for newspaper articles comprised 10 items across 5 domains: reliability, usefulness, understandability, sufficiency, and transparency. The interrater agreement for the article on colorectal cancer was in the moderate to substantial range (Fleiss κ=0.48, SE 0.11; Gwet agreement coefficient=0.74, SE 0.13), while for the article introducing obesity genetic testing it was in the substantial range, with values of 0.63 (SE 0.28) and 0.86 (SE 0.10) for the two measures, respectively. There was relatively low agreement for the article on hypertension diagnostic criteria at 0.20 (SE 0.10) and 0.75 (SE 0.13), respectively. Validity of the correlation assessed with the Kendall τ showed good correlation between tools (HIQUAL vs DISCERN=0.72, HIQUAL vs QUEST [Quality Evaluation Scoring Tool]=0.69). CONCLUSIONS We developed a new assessment tool to evaluate the quality of health information in online newspaper articles, to help consumers discern accurate sources of health information. The HIQUAL can help increase the accuracy and quality of online health information in Korea.

Background Varicella is a highly contagious disease caused by the varicella-zoster virus (VZV). Given its tendency to cluster geographically, spatial analyses may provide better understanding of the pattern of varicella transmission. We investigated the spatial characteristics of varicella in Korea and the risk factors for varicella at a national level. Methods Using national surveillance and demographic data, we examined the spatial distribution of incidence rates and their spatial autocorrelation and calculated Moran’s index. Spatial regression analysis was used to identify sociodemographic predictors of varicella incidence at the district level. Results An increasing tendency in the annual incidence of varicella was observed over a 12-year period (2006–2017), with a surge in 2017. There was a clear positive spatial autocorrelation of the varicella incidence rate during the surveillance period. During 2006–2014, High-High (HH) clusters were mostly confined to the northeast region and neighboring districts. Population density and the number of hospitals per 1,000 persons had negative coefficients, and the former was significant. Childhood percentage, percentage of children under 12 years of age among total population, and vaccine coverage rate had positive coefficients, but only the former was significant. Conclusion There was a temporal uptrend in the incidence of varicella in Korea from 2006 to 2017 in the setting of positive spatial associations. The varicella incidence according to geographic region varied with population density, childhood percentage, suggesting the importance of the community-level surveillance and monitoring strategies.

After South Korea raised its infectious disease alert to the highest level in response to coronavirus disease emergence, tuberculosis notification during the first 18 weeks of 2020 decreased significantly from the same period for each year during 2015-2019. Adequate measures to diagnose, control, and prevent tuberculosis need to be maintained.

Objectives To determine the impact of restrictions on mobility on reducing transmission of COVID-19. Design Daily incidence rates lagged by 14 days were regressed on mobility changes using LOESS regression and logit regression between the day of the 100th case in each country to August 31, 2020. Setting 34 OECD countries plus Singapore and Taiwan. Participants Google mobility data were obtained from people who turned on mobile device-based global positioning system (GPS) and agreed to share their anonymized position information with Google. Interventions We examined the association of COVID-19 incidence rates with mobility changes, defined as changes in categories of domestic location, against a pre-pandemic baseline, using country-specific daily incidence data on newly confirmed COVID-19 cases and mobility data. Results In two thirds of examined countries, reductions of up to 40% in commuting mobility (to workplaces, transit stations, retailers, and recreation) were associated with decreased COVID-19 incidence, more so early in the pandemic. However, these decreases plateaued as mobility remained low or decreased further. We found smaller or negligible associations between mobility restriction and incidence rates in the late phase in most countries. Conclusion Mild to moderate degrees of mobility restriction in most countries were associated with reduced incidence rates of COVID-19 that appear to attenuate over time, while some countries exhibited no effect of such restrictions. More detailed research is needed to precisely understand the benefits and limitations of mobility restrictions as part of the public health response to the COVID-19 pandemic. WHAT IS ALREADY KNOWN ON THIS TOPIC Since SARS-CoV-2 became a pandemic, restrictions on mobility such as limitations on travel and closure of offices, restaurants, and shops have been imposed in an unprecedented way in both scale and scope to prevent the spread of COVID-19 in the absence of effective treatment options or a vaccine. Although mobility restriction has also brought about tremendous costs such as negative economic growth and other collateral impacts on health such as increased morbidity and mortality from lack of access to other essential health services, little evidence exists on the effectiveness of mobility restriction for the prevention of disease transmission. A search of PUBMED and Google Scholar for publications on this topic through Sep 20, 2020 revealed that most of the evidence on the effectiveness of physical distancing comes from mathematical modeling studies using a variety of assumptions. One study investigated only the combined effect of several interventions, including physical distancing, among SARS-CoV-2 infected patients. WHAT THIS STUDY ADDS This is the first study to investigate the association between change in mobility and incidence of COVID-19 globally using real-time measures of mobility at the population level. For this, we used Google Global Mobility data and the daily incidence of COVID-19 for 36 countries from the day of 100th case detection through August 31, 2020. Our findings from LOESS regression show that in two-thirds of countries, reductions of up to 40% in commuting mobility were associated with decreased COVID-19 incidence, more so early in the pandemic. This decrease, however, plateaued as mobility decreased further. We found that associations between mobility restriction and incidence became smaller or negligible in the late phase of the pandemic in most countries. The reduced incidence rate of COVID-19 cases with a mild to moderate degree of mobility restriction in most countries suggests some value to limited mobility restriction in early phases of epidemic mitigation. The lack of impact in some others, however, suggests further research is needed to confirm these findings and determine the distinguishing factors for when mobility restrictions are helpful in decreasing viral transmission. Governments should carefully consider the level and period of mobility restriction necessary to achieve the desired benefits and minimize harm.

Objective This study aimed to describe the conceptualization, development, and implementation processes of the newly established Korean Cardiac Arrest Resuscitation Consortium (KoCARC) to improve out-of-hospital cardiac arrest (OHCA) outcomes. Methods The KoCARC was established in 2014 by recruiting hospitals willing to participate voluntarily. To enhance professionalism in research, seven research committees, the Epidemiology and Preventive Research Committee, Community Resuscitation Research Committee, Emergency Medical System Resuscitation Research Committee, Hospital Resuscitation Research Committee, Hypothermia and Postresuscitation Care Research Committee, Cardiac Care Resuscitation Committee, and Pediatric Resuscitation Research Committee, were organized under a steering committee. The KoCARC registry was developed with variables incorporated in the currently existing regional OHCA registries and Utstein templates and were collected via a web-based electronic database system. The KoCARC study population comprises patients visiting the participating hospitals who had been treated by the emergency medical system for OHCA presumed to have a cardiac etiology. Results A total of 62 hospitals volunteered to participate in the KoCARC, which captures 33.0% of the study population in Korea. Web-based data collection started in October 2015, and to date (December 2016), there were 3,187 cases compiled in the registry collected from 32 hospitals. Conclusion The KoCARC is a self-funded, voluntary, hospital-based collaborative research network providing high level evidence in the field of OHCA and resuscitation. This paper will serve as a reference for subsequent KoCARC manuscripts and for data elements collected in the study.

Background Cut-off values for visceral fat area (VFA) measured by computed tomography (CT) for identifying individuals at risk of metabolic syndrome (MetS) have not been clearly established in Korean adults, particularly for large populations. We aimed to identify optimal VFA and waist circumference (WC) cut-off values and compare the ability of VFA and WC to predict the presence of ≥2 metabolic risk factors. Methods We included 36,783 subjects aged 19-79 years undergoing abdominal fat CT during regular health checkups between January 2007 and February 2015 in Seoul. The risk factors for MetS except WC were based on the International Diabetes Federation criteria. Receiver operating characteristic curve analyses were used to determine the appropriate VFA and WC cut-off values for MetS. Results VFA was a more significant predictor of metabolic risk factors than WC and body mass index (BMI). The optimal cut-off values for VFA and WC were 134.6 cm2 and 88 cm for men and 91.1 cm2 and 81 cm for women, respectively. We estimated age-specific cut-off values for VFA, WC, and BMI. VFA cut-off values increased with age, particularly among women. Conclusion This large population study proposed the cut-off values for VFA and WC for identifying subjects at risk of MetS among Korean adults. For more accurate diagnosis, different age-specific cut-off values for VFA and WC may be considered.

In ecological studies, researchers often try to convey the analysis results to individual level based on aggregate data. In order to do this correctly, the possibility of ecological bias should be studied and addressed. One of the key ideas used to address the ecological bias issue is to derive the ecological model from the individual model and to check whether the parameter of interest in the individual model is identifiable in the ecological model. However, the procedure depends on unverifiable assumptions, and we recommend checking how sensitive the results are to these unverifiable assumptions. We analyzed the tuberculosis data that was collected in Seoul in 2005 using a spatial ecological regression model for the aggregate count data with spatial correlation, and found that the deprivation index is likely to have a small positive effect on the occurrence risk of tuberculosis in individual level in Seoul. We considered this finding in various aspects by performing in depth sensitivity analyses. In particular, our findings are shown to be robust to the distribution assumptions for the individual exposure and missing binary covariate across various scenarios.

Detecting local spatial clusters for count data is an important task in spatial epidemiology. Two broad approaches—moving window and disease mapping methods—have been suggested in some of the literature to find clusters. However, the existing methods employ somewhat arbitrarily chosen tuning parameters, and the local clustering results are sensitive to the choices. In this paper, we propose a penalized likelihood method to overcome the limitations of existing local spatial clustering approaches for count data. We start with a Poisson regression model to accommodate any type of covariates, and formulate the clustering problem as a penalized likelihood estimation problem to find change points of intercepts in two-dimensional space. The cost of developing a new algorithm is minimized by modifying an existing least absolute shrinkage and selection operator algorithm. The computational details on the modifications are shown, and the proposed method is illustrated with Seoul tuberculosis data.

Background Self-management of lifestyle and cardiovascular disease risk factors is challenging in older patients with coronary heart disease (CHD). SMS text messaging could be a potential support tool for self-management and the most affordable and accessible method through a mobile phone. High-quality evidence had been lacking, and previous studies evaluated the effects of SMS text messaging on the subjective measures of short-term outcomes. Recently, a large-sized randomized controlled trial in Australia reported promising findings on the objective measures upon 6-month follow-up. However, an examination of the effectiveness of such interventions in an Asian population with unique demographic characteristics would be worthwhile. Objective This study examined the effectiveness of a 1-way SMS text messaging program to modify the lifestyle and cardiovascular disease risk factors of patients who underwent the first percutaneous coronary intervention (PCI). Methods A parallel, single-blinded, 1:1 random allocation clinical trial was conducted with 879 patients treated through PCI. They were recruited during hospital admission from April 2017 to May 2020 at 2 university hospitals in the Republic of Korea. In addition to standard care, the intervention group received access to a supporting website and 4 SMS text messages per week for 6 months regarding a healthy diet, physical activity, smoking cessation, and cardiovascular health. Random allocation upon study enrollment and SMS text messaging after hospital discharge were performed automatically using a computer program. The coprimary outcomes were low-density-lipoprotein cholesterol (LDL-C), systolic blood pressure (SBP), and BMI. The secondary outcomes were change in lifestyle and adherence to the recommended health behaviors. Results Of the eligible population, 440 and 439 patients who underwent PCI were assigned to the intervention and control groups, respectively. The 1-way SMS text messaging program significantly enhanced physical activity (P=.02), healthy diet (P Conclusions Lifestyle-focused SMS text messages were effective in the self-management of a healthy diet, exercise, and medication adherence, but their influence on the physiological measures was not significant. One-way SMS text messages can be used as an affordable adjuvant method for lifestyle modification to help prevent the recurrence of cardiovascular disease. Trial Registration Clinical Research Information Service (CRiS) KCT0005087; https://cris.nih.go.kr/cris/search/detailSearch.do/19282

Background Concern regarding the reliability and accuracy of the health-related information provided by online newspaper articles has increased. Numerous criteria and items have been proposed and published regarding the quality assessment of online information, but there is no standard quality assessment tool available for online newspapers. Objective This study aimed to develop the Health Information Quality Assessment Tool (HIQUAL) for online newspaper articles. Methods We reviewed previous health information quality assessment tools and related studies and accordingly developed and customized new criteria. The interrater agreement for the new assessment tool was assessed for 3 newspaper articles on different subjects (colorectal cancer, obesity genetic testing, and hypertension diagnostic criteria) using the Fleiss κ and Gwet agreement coefficient. To compare the quality scores generated by each pair of tools, convergent validity was measured using the Kendall τ ranked correlation. Results Overall, the HIQUAL for newspaper articles comprised 10 items across 5 domains: reliability, usefulness, understandability, sufficiency, and transparency. The interrater agreement for the article on colorectal cancer was in the moderate to substantial range (Fleiss κ=0.48, SE 0.11; Gwet agreement coefficient=0.74, SE 0.13), while for the article introducing obesity genetic testing it was in the substantial range, with values of 0.63 (SE 0.28) and 0.86 (SE 0.10) for the two measures, respectively. There was relatively low agreement for the article on hypertension diagnostic criteria at 0.20 (SE 0.10) and 0.75 (SE 0.13), respectively. Validity of the correlation assessed with the Kendall τ showed good correlation between tools (HIQUAL vs DISCERN=0.72, HIQUAL vs QUEST [Quality Evaluation Scoring Tool]=0.69). Conclusions We developed a new assessment tool to evaluate the quality of health information in online newspaper articles, to help consumers discern accurate sources of health information. The HIQUAL can help increase the accuracy and quality of online health information in Korea.

Objective Chest pain is one of the most common complaints in the emergency department (ED). Cardiac computed tomography angiography (CCTA) is a frequently used tool for the early triage of patients with low- to intermediate-risk acute chest pain. We present a study protocol for a multicenter prospective randomized controlled clinical trial testing the hypothesis that a low-dose CCTA protocol using prospective electrocardiogram (ECG)-triggering and limited-scan range can provide sufficient diagnostic safety for early triage of patients with acute chest pain. Methods The trial will include 681 younger adult (aged 20 to 55) patients visiting EDs of three academic hospitals for acute chest pain or equivalent symptoms who require further evaluation to rule out acute coronary syndrome. Participants will be randomly allocated to either low-dose or conventional CCTA protocol at a 2:1 ratio. The low-dose group will undergo CCTA with prospective ECG-triggering and restricted scan range from sub-carina to heart base. The conventional protocol group will undergo CCTA with retrospective ECG-gating covering the entire chest. Patient disposition is determined based on computed tomography findings and clinical progression and all patients are followed for a month. The primary objective is to prove that the chance of experiencing any hard event within 30 days after a negative low-dose CCTA is less than 1%. The secondary objectives are comparisons of the amount of radiation exposure, ED length of stay and overall cost. Results and conclusion Our low-dose protocol is readily applicable to current multi-detector computed tomography devices. If this study proves its safety and efficacy, dose-reduction without purchasing of expensive newer devices would be possible.

Aim Renal hyperfiltration (RHF) is a marker of early kidney injury that was recently shown to be a novel marker of mortality. However, it has no clear definition. In this study, we suggested an age- and sex-adjusted RHF definition and explored the association between RHF and mortality by sex. Methods We analyzed data from individuals receiving routine health examinations from 1995 to 2009. RHF was defined as an estimated glomerular filtration rate over the 95th percentile matched for age and sex. Results A total of 114 966 individuals were included. During the 75-month of observation period, 2559 (2.2%) participants died. Among those, 71.4% were men. Because sex and RHF had a significant interaction for mortality (P for interaction

Aims The relationship between directly measured body fat and all-cause mortality has been rarely studied. The aim of this study was to evaluate the predictive significance of computed tomography (CT)-measured body fat, including both visceral fat area (VFA) and subcutaneous fat area (SFA), for mortality. Methods The study included 36,656 participants who underwent abdominal CT as part of a health check-up at a single university-affiliated healthcare centre in 2007–2015. Of those, 32,593 participants with data regarding vital status as of May 2016 were included in the final analysis. The main factors evaluated were VFA, SFA and visceral-to-subcutaneous fat area ratio (VSR), and the primary outcome was all-cause mortality. Results There were 253 deaths during a mean follow-up of 5.7 years. Increased SFA was associated with decreased all-cause mortality, whereas an increased VFA and VSR were related to increased all-cause mortality. Compared with the predictive power of body mass index (BMI), SFA and VSR showed a larger area under the curve than did BMI. In Kaplan-Meier survival curve analysis, increased SFA and VSR were associated with decreased and increased hazard of all-cause death, respectively. However, in multivariate Cox proportional hazard regression analysis, only VSR was independently associated with all-cause mortality. Moreover, this relationship was paralleled by the harmful impact of increased VSR on metabolic profiles. Conclusions Increased VSR was an independent predictor of all-cause mortality. This suggests that the location of fat deposits may be more important than the actual amount of body fat.

We compared the temporal trends in survival and neurological outcomes after out-of-hospital cardiac arrest (OHCA) in men and women.A nationwide, population-based observational study enrolled adults with OHCA of presumed cardiac origin from 2008 to 2015. The main outcomes were survival and neurological recovery. We performed trend analyses of potential risk factors and outcomes. Adjusted odd ratios (aOR) were calculated using multivariate logistic regression analysis after adjusting for confounders. To assess whether outcomes had improved over time in both sexes, we calculated the yearly risk-adjusted survival rates and neurological recovery rate for the study period.We included 121,900 patients in the final analysis. Women comprised 36.2% of the patients. During the study, survival improved in both sexes, from 3.2% to 7.9% in men and from 1.8% to 3.7% in women. Neurological recovery improved in men from 1.1% to 5.9% and in women from 0.7% to 2.3%. The risk-adjusted survival rates increased significantly in men from 3.2% in 2008 to 5.7% in 2015 (p for trend0.01); these rates did not increase to the same degree in women (from 1.8% in 2008 to 3.4% in 2015; p for trend0.01). After adjusting for confounders, the risk-adjusted neurological recovery rate increased from 1.1% in 2008 to 4.3% in 2015 (p for trend0.01) in men. This improvement trend was lower in women (from 0.7% in 2008 to 1.5% in 2015, p for trend0.01).The outcomes of OHCA improved in both sexes during the study period. The degree of improvement in outcomes was higher in men than in women.

Objectives The purpose of this study was to investigate the health effects of air conditioning use during the 2018 heat wave in Korea, included the highest temperature ever recorded in the nation. Methods The participants in this study were 1000 adults aged 19 years and older recruited from across Korea. The participants were asked about their experience of symptoms of various diseases, disruptions of their daily lives, and use of air conditioning during the heat wave. The associations between air conditioning use during the heat wave and health outcomes were analyzed using the chi-square test and multiple logistic regression models. Results Among participants who lacked air conditioning in the main space where they spent time outside the home, 33.9%, 8.1%, 43.5%, and 19.4% experienced symptoms of heat-related, cardiovascular, nervous system diseases, and air-conditioningitis, respectively. In comparison, participants who did have air conditioning outside the home experienced the same symptoms at proportions of 21.0%, 1.9%, 26.8%, and 34.2%, respectively (p=0.027, 0.007, 0.007, and 0.023, respectively). Among participants who had no air conditioner at home, 10.0% were absent from school or work due to the heat wave. In contrast, among participants who had an air conditioner at home, only 3.7% were absent as a result of the heat wave (p=0.007). Conclusions When air conditioning was not used at home or in the main space where participants spent time outside the home during the 2018 heat wave, adverse health effects were more prevalent, but the risk of air-conditioningitis was reduced.

Background: Chronic obstructive pulmonary disease (COPD) is a leading cause of mortality, therefore the prediction of mortality in COPD patients is crucial. In the current study, the abilities of different categorization systems to predict mortality in stable COPD patients from a prospective cohort were compared. Methods: The ability to predict mortality was compared in terms of discrimination by Harrell’s C (HC) index and calibration using graphical comparison among the GOLD (Global Initiative for Chronic Obstructive Lung Disease) 2011, GOLD 2017, GOLD grade, BODE (BMI, Airflow Obstruction, Dyspnea, Exercise), updated BODE, BODEx (BMI, Airflow Obstruction, Dyspnea, Exacerbation), e-BODE (Exacerbation and BODE), ADO (Age, Dyspnea, Airflow Obstruction), COPD prognostic index (CPI), and simplified/optimized B-AE-D (BMI, Acute Exacerbation, Dyspnea) indexes. Results: The study included 520 patients, of whom 63 died during a median 40-month follow-up period. Combined prediction systems exhibited higher discrimination properties than single predictors. The CPI exhibited the highest with a HC of 0.768, followed by the simplified B-AE-D (HC 0.761), ADO (HC 0.760), and optimized B-AE-D (HC 0.756). The BODE and its variants other than the ADO exhibited relatively lower HCs (0.656–0.705), and GOLD exhibited the lowest discrimination ability among the combined indices (HCs 0.628–0.637). Subjective symptom questionnaires such as the modified Medical Research Council (mMRC) scale (HC 0.693) and SGRQ (HC 0.679) exhibited the highest ability to predict mortality among the single indices. Conclusion: The ADO, simplified B-AE-D, optimized B-AE-D, and GOLD 2017 exhibited good calibration properties, but the CPI did not. The simplified and optimized B-AE-Ds and the ADO index had good discrimination and calibration properties for the prediction of mortality in stable COPD patients.

The first case of human brucellosis in South Korea was reported in 2002, and cases of human infection continue to occur. Although an association between human and bovine brucellosis has been identified, the spatial relationship has not been studied in South Korea. Here, we analysed the spatial patterns of human and bovine brucellosis retrieved from the human and veterinary surveillance data, as well as the spatial correlation between human and bovine brucellosis and associated factors that contribute to its occurrence. The risk of human brucellosis was analysed using a Bayesian spatial model with potential risk factors. Our results show that, for both human and bovine brucellosis, hotspots were clustered in the southeast regions of Korea, whereas coldspots were clustered in the northwest regions of Korea. Our study suggests that the risk of human brucellosis increases in rural regions with the highest risk of bovine brucellosis. Collaborative strategies between human and veterinary health sectors (e.g, public health intervention and region-specific eradication programs for bovine brucellosis) would reduce the burden of brucellosis in South Korea.

Online supplement (DOC). Figure S1. Histograms showing propensity score distribution. Table S1. Baseline characteristics of the study patients before and after propensity score matching. Table S2. Adjusted incidence rates of moderate or severe exacerbations by exposure groups (sensitivity analysis). Table S3. Incidence rates of moderate or severe exacerbations in the propensity score-matched cohort (sensitivity analysis) (DOC 117 kb)

Background/objectives The measurement of body composition, including muscle and fat mass, remains challenging in large epidemiological studies due to time constraint and cost when using accurate modalities. Therefore, this study aimed to develop and validate prediction equations according to sex to measure lean body mass (LBM), appendicular skeletal muscle mass (ASM), and body fat mass (BFM) using anthropometric measurement, serum creatinine level, and lifestyle factors as independent variables and dual-energy X-ray absorptiometry as the reference method. Subjects/methods A sample of the Korean general adult population (men: 7,599; women: 10,009) from the Korean National Health and Nutrition Examination Survey 2008-2011 was included in this study. The participants were divided into the derivation and validation groups via a random number generator (with a ratio of 70:30). The prediction equations were developed using a series of multivariable linear regressions and validated using the Bland-Altman plot and intraclass correlation coefficient (ICC). Results The initial and practical equations that included age, height, weight, and waist circumference had a different predictive ability for LBM (men: R2 = 0.85, standard error of estimate [SEE] = 2.7 kg; women: R2 = 0.78, SEE = 2.2 kg), ASM (men: R2 = 0.81, SEE = 1.6 kg; women: R2 = 0.71, SEE = 1.2 kg), and BFM (men: R2 = 0.74, SEE = 2.7 kg; women: R2 = 0.83, SEE = 2.2 kg) according to sex. Compared with the first prediction equation, the addition of other factors, including serum creatinine level, physical activity, smoking status, and alcohol use, resulted in an R2 that is higher by 0.01 and SEE that is lower by 0.1. Conclusions All equations had low bias, moderate agreement based on the Bland-Altman plot, and high ICC, and this result showed that these equations can be further applied to other epidemiologic studies.