Although WHO declared the end of the public health emergency for coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARSCoV-2), XBB lineages continue to evolve and emerge globally. In particular, XBB.1.5 and XBB.1.16 are raising concerns because of their high immune evasion, leading to apprehensions regarding vaccine efficacy reduction and potential reinfection. We aimed to investigate the COVID-19 outbreak in Korea and predict the likelihood of reinfection by testing neutralizing activity against live viruses from the S clade and 19 Omicron sublineages.We found a significant risk of infection with the currently prevalent XBB lineage for individuals who were either vaccinated early or infected during the initial Omicron outbreak. Vaccinated individuals were better equipped than unvaccinated individuals to produce neutralizing antibodies for other SARS-CoV-2 variants upon infection. Therefore, unvaccinated individuals do not easily develop neutralizing activity against other variants and face the highest risk of reinfection by the XBB lineage. Our study provides important information to facilitate the development of strategies for monitoring populations that would be the most susceptible to new COVID-19 outbreaks.

Objective: The present study aimed to verify the efficacy of calcium ions as a prognostic factor for massive transfusion (MT) in patients with upper gastrointestinal bleeding (UGIB), including those of variceal and non-variceal origin. Methods: This retrospective cohort study included adult patients with acute UGIB hospitalized through the prehospital emergency department between January 2018 and December 2022. The primary outcome was the need for MT. Secondary outcomes comprised hospital mortality, the need for angiographic intervention or surgery, length of hospital stay, and length of intensive care unit stay. Multivariate analysis using logistic regression was performed for possible candidates and included ionized calcium levels for predicting MT. Results: According to the multivariate logistic regression assessment, the primary outcome was independently correlated with hemoglobin (odds ratio [OR]=0.702; 95% confidence interval [CI], 0.554-0.889) and ionized calcium levels (OR=0.009; 95% CI, 0.0002-0.469). The optimal cutoff point for ionized calcium levels was determined to be a value of 1.105, with a sensitivity of 0.88 and a specificity of 0.488. Using this value, the lower ionized calcium group needed a nearly six-fold increase in MT compared to the upper group. However, the secondary outcomes did not show any statistical differences. Conclusion The statistical review in the present study indicates that low ionized calcium levels in UGIB patients, regardless of liver cirrhosis as a comorbidity, are a novel independent prognostic factor for MT. Quick measurement of ionized calcium levels using a blood gas analyzer will enable practitioners to rapidly identify UGIB patients who need urgent care in minutes.

Objective: The present study aimed to verify the efficacy of calcium ions as a prognostic factor for massive transfusion (MT) in patients with upper gastrointestinal bleeding (UGIB), including those of variceal and non-variceal origin. Methods: This retrospective cohort study included adult patients with acute UGIB hospitalized through the prehospital emergency department between January 2018 and December 2022. The primary outcome was the need for MT. Secondary outcomes comprised hospital mortality, the need for angiographic intervention or surgery, length of hospital stay, and length of intensive care unit stay. Multivariate analysis using logistic regression was performed for possible candidates and included ionized calcium levels for predicting MT. Results: According to the multivariate logistic regression assessment, the primary outcome was independently correlated with hemoglobin (odds ratio [OR]=0.702; 95% confidence interval [CI], 0.554-0.889) and ionized calcium levels (OR=0.009; 95% CI, 0.0002-0.469). The optimal cutoff point for ionized calcium levels was determined to be a value of 1.105, with a sensitivity of 0.88 and a specificity of 0.488. Using this value, the lower ionized calcium group needed a nearly six-fold increase in MT compared to the upper group. However, the secondary outcomes did not show any statistical differences. Conclusion The statistical review in the present study indicates that low ionized calcium levels in UGIB patients, regardless of liver cirrhosis as a comorbidity, are a novel independent prognostic factor for MT. Quick measurement of ionized calcium levels using a blood gas analyzer will enable practitioners to rapidly identify UGIB patients who need urgent care in minutes.

Objective: The present study aimed to verify the efficacy of calcium ions as a prognostic factor for massive transfusion (MT) in patients with upper gastrointestinal bleeding (UGIB), including those of variceal and non-variceal origin. Methods: This retrospective cohort study included adult patients with acute UGIB hospitalized through the prehospital emergency department between January 2018 and December 2022. The primary outcome was the need for MT. Secondary outcomes comprised hospital mortality, the need for angiographic intervention or surgery, length of hospital stay, and length of intensive care unit stay. Multivariate analysis using logistic regression was performed for possible candidates and included ionized calcium levels for predicting MT. Results: According to the multivariate logistic regression assessment, the primary outcome was independently correlated with hemoglobin (odds ratio [OR]=0.702; 95% confidence interval [CI], 0.554-0.889) and ionized calcium levels (OR=0.009; 95% CI, 0.0002-0.469). The optimal cutoff point for ionized calcium levels was determined to be a value of 1.105, with a sensitivity of 0.88 and a specificity of 0.488. Using this value, the lower ionized calcium group needed a nearly six-fold increase in MT compared to the upper group. However, the secondary outcomes did not show any statistical differences. Conclusion The statistical review in the present study indicates that low ionized calcium levels in UGIB patients, regardless of liver cirrhosis as a comorbidity, are a novel independent prognostic factor for MT. Quick measurement of ionized calcium levels using a blood gas analyzer will enable practitioners to rapidly identify UGIB patients who need urgent care in minutes.

Background: It is well known that a large number of patients with diabetes also have dyslipidemia, which significantly increases the risk of cardiovascular disease (CVD). This study aimed to evaluate the efficacy and safety of combination drugs consisting of metformin and atorvastatin, widely used as therapeutic agents for diabetes and dyslipidemia. Methods: This randomized, double-blind, placebo-controlled, parallel-group and phase III multicenter study included adults with glycosylated hemoglobin (HbA1c) levels >7.0% and <10.0%, low-density lipoprotein cholesterol (LDL-C) >100 and <250 mg/dL. One hundred eighty-five eligible subjects were randomized to the combination group (metformin+atorvastatin), metformin group (metformin+atorvastatin placebo), and atorvastatin group (atorvastatin+metformin placebo). The primary efficacy endpoints were the percent changes in HbA1c and LDL-C levels from baseline at the end of the treatment. Results: After 16 weeks of treatment compared to baseline, HbA1c showed a significant difference of 0.94% compared to the atorvastatin group in the combination group (0.35% vs. −0.58%, respectively; P<0.0001), whereas the proportion of patients with increased HbA1c was also 62% and 15%, respectively, showing a significant difference (P<0.001). The combination group also showed a significant decrease in LDL-C levels compared to the metformin group (−55.20% vs. −7.69%, P<0.001) without previously unknown adverse drug events. Conclusion The addition of atorvastatin to metformin improved HbA1c and LDL-C levels to a significant extent compared to metformin or atorvastatin alone in diabetes and dyslipidemia patients. This study also suggested metformin’s preventive effect on the glucose-elevating potential of atorvastatin in patients with type 2 diabetes mellitus and dyslipidemia, insufficiently controlled with exercise and diet. Metformin and atorvastatin combination might be an effective treatment in reducing the CVD risk in patients with both diabetes and dyslipidemia because of its lowering effect on LDL-C and glucose.

Background: To analyze the outcomes of clipping and coiling for ruptured intracranial aneurysms (RIAs) based on data from the National Health Insurance Service in South Korea, with a focus on variations according to region and hospital size. Methods: This study analyzed the one-year mortality rates for patients with RIAs who underwent clipping or coiling in 2018. Coiling was further categorized into non-stent assisted coiling (NSAC) and stent assisted coiling (SAC). Hospitals were classified as tertiary referral general hospitals (TRGHs), general hospitals (GHs), or semi-general hospitals (sGHs) based on size. South Korea’s administrative districts were divided into 15 regions for analysis. Results: In 2018, there were 2,194 (33.1%) clipping procedures (TRGH, 985; GH, 827; sGH, 382) and 4,431 (66.9%) coiling procedures (TRGH, 1,642; GH, 2076; sGH, 713) performed for RIAs treatment. Among hospitals performing more than 20 treatments, the one-year mortality rates following clipping or coiling were 11.2% and 16.0%, respectively, with no significant difference observed. However, there was a significant difference in one-year mortality between NSAC and SAC (14.3% vs. 19.5%, P = 0.034), with clipping also showing significantly lower mortality compared to SAC (P = 0.019). No significant differences in other treatment modalities were observed according to hospital size, but clipping at TRGHs had significantly lower mortality than at GHs (P = 0.042). While no significant correlation was found between the number of treatments and outcomes at GHs, at TRGHs, a higher volume of clipping procedures was significantly associated with lower total mortality (P = 0.023) and mortality after clipping (P = 0.022). Conclusion Using Korea NHIS data, mortality rates for RIAs showed no significant variation by hospital size due to coiling’s prevalence. However, differences in clipping outcomes by hospital size and volume in TRGH highlight the need for national efforts to improve clipping skills and standardization. Additionally, the higher mortality rate with SAC emphasizes the importance of precise indications for its application.

Objective: This study examined whether the European Society of Cardiology (ESC) 0/1-hour algorithm using a high-sensitivity troponin I (hs-cTnI) assay can effectively classify patients presenting with chest pain at the emergency department. Methods: This study conducted a retrospective chart review of patients presenting with chest pain suspicious of myocardial ischemia. hs-cTnI was measured at presentation and after one hour. The patients were classified into three groups using hs-cTnI: rule out, observation, and rule in according to the ESC 0/1-hour algorithm to evaluate the diagnostic performance of acute myocardial infarction (AMI). This study evaluated the negative predictive value (NPV), positive predictive value (PPV), sensitivity, specificity, and the proportion of patients assigned to the observation. Results: Among 384 patients, 77 were diagnosed with AMI. Following classification using the ESC 0/1-hour algorithm, there were 206 (53.6%), 77 (20.1%), and 101 (26.3%) patients were classified as “rule-out,” “rule-in,” and “observation,” respectively. In “rule-out,” the NPV and sensitivity for AMI were 99.0% (95% confidence interval [CI], 96.5-99.9) and 97.4% (95% CI, 90.9-99.7), respectively. In “rule-in,” the PPV and specificity for AMI were 83.1% (95% CI, 72.9-90.7) and 95.8% (95% CI, 92.9-97.7). Conclusion The ESC 0/1-hour algorithm allows for quick and accurate categorization of patients presenting with ischemic chest pain into the “rule-out” or “rule-in” group for the diagnosis of AMI. Therefore, applying this accelerated algorithm for evaluating chest pain in the emergency department in Korean patients would be helpful.

Background: During the coronavirus disease 2019 (COVID-19) pandemic, there was a shortage of medical resources and the need for proper treatment guidelines for brain tumor patients became more pressing. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, has undertaken efforts to develop a guideline that is tailored to the domestic situation and that can be used in similar crisis situations in the future. As part II of the guideline, this consensus survey is to suggest management options in specific clinical scenarios during the crisis period. Methods: The KSNO Guideline Working Group consisted of 22 multidisciplinary experts on neuro-oncology in Korea. In order to confirm a consensus reached by the experts, opinions on 5 specific clinical scenarios about the management of brain tumor patients during the crisis period were devised and asked. To build-up the consensus process, Delphi method was employed. Results: The summary of the final consensus from each scenario are as follows. For patients with newly diagnosed astrocytoma with isocitrate dehydrogenase (IDH)-mutant and oligodendroglioma with IDH-mutant/1p19q codeleted, observation was preferred for patients with low-risk, World Health Organization (WHO) grade 2, and Karnofsky Performance Scale (KPS) ≥60, while adjuvant radiotherapy alone was preferred for patients with high-risk, WHO grade 2, and KPS ≥60. For newly diagnosed patients with glioblastoma, the most preferred adjuvant treatment strategy after surgery was radiotherapy plus temozolomide except for patients aged ≥70 years with KPS of 60 and unmethylated MGMT promoters. In patients with symptomatic brain metastasis, the preferred treatment differed according to the number of brain metastasis and performance status. For patients with newly diagnosed atypical meningioma, adjuvant radiation was deferred in patients with older age, poor performance status, complete resection, or low mitotic count. Conclusion It is imperative that proper medical care for brain tumor patients be sustained and provided, even during the crisis period. The findings of this consensus survey will be a useful reference in determining appropriate treatment options for brain tumor patients in the specific clinical scenarios covered by the survey during the future crisis.

Background: During the coronavirus disease 2019 (COVID-19) pandemic, the need for appropriate treatment guidelines for patients with brain tumors was indispensable due to the lack and limitations of medical resources. Thus, the Korean Society for Neuro-Oncology (KSNO), a multidisciplinary academic society, has undertaken efforts to develop a guideline that is tailored to the domestic situation and that can be used in similar crisis situations in the future. Methods: The KSNO Guideline Working Group was composed of 22 multidisciplinary experts on neuro-oncology in Korea. In order to reach consensus among the experts, the Delphi method was used to build up the final recommendations. Results: All participating experts completed the series of surveys, and the results of final survey were used to draft the current consensus recommendations. Priority levels of surgery and radiotherapy during crises were proposed using appropriate time window-based criteria for management outcome. The highest priority for surgery is assigned to patients who are life-threatening or have a risk of significant impact on a patient’s prognosis unless immediate intervention is given within 24–48 hours. As for the radiotherapy, patients who are at risk of compromising their overall survival or neurological status within 4–6 weeks are assigned to the highest priority. Curative-intent chemotherapy has the highest priority, followed by neoadjuvant/adjuvant and palliative chemotherapy during a crisis period. Telemedicine should be actively considered as a management tool for brain tumor patients during the mass infection crises such as the COVID-19 pandemic. Conclusion It is crucial that adequate medical care for patients with brain tumors is maintained and provided, even during times of crisis. This guideline will serve as a valuable resource, assisting in the delivery of treatment to brain tumor patients in the event of any future crisis.

Objective: This study evaluates the impact of the coronavirus disease 2019 (COVID-19) pandemic on emergency medical service (EMS) responses and out-of-hospital cardiac arrest (OHCA) outcomes. Methods: This is a retrospective comparison study analyzing the OHCA data of a university medical center in Seoul during the COVID-19 pandemic period (January 2020-January 2021) and non-pandemic period (January 2019-January 2020). The EMS response time and OHCA outcomes were compared between both periods. Based on the weekly mean number of confirmed cases and their EMS response time, patients were classified into six groups and OHCA outcomes were compared. Results: This study evaluated 309 OHCA patients (non-pandemic period of 146, pandemic period of 163). Significant delays in the EMS response and transport time were observed during the pandemic period. However, no significant differences were obtained in the rate of return of spontaneous circulation (ROSC) and survival at discharge (12.4% in pandemic vs. 13.8% in non-pandemic; P=0.722). According to the weekly mean COVID-19 incidence when patients were over 100, there was a significant increase in the EMS response and transport time, whereas ROSC and survival rate were dramatically decreased. Conclusion During the pandemic, the EMS service for OHCA patients was worse than before, with delayed and reduced survival for OHCA patients. We further determined that an increase in the number of COVID-19 cases (especially when weekly mean numbers were over 100) dramatically delayed the EMS response time. This resulted in a very low survival rate of OHCA patients.