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.

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.

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.