Purpose: This subgroup analysis of the Korean subset of patients in the phase 3 LASER301 trial evaluated the efficacy and safety of lazertinib versus gefitinib as first-line therapy for epidermal growth factor receptor mutated (EGFRm) non–small cell lung cancer (NSCLC). Materials and Methods: Patients with locally advanced or metastatic EGFRm NSCLC were randomized 1:1 to lazertinib (240 mg/day) or gefitinib (250 mg/day). The primary endpoint was investigator-assessed progression-free survival (PFS). Results: In total, 172 Korean patients were enrolled (lazertinib, n=87; gefitinib, n=85). Baseline characteristics were balanced between the treatment groups. One-third of patients had brain metastases (BM) at baseline. Median PFS was 20.8 months (95% confidence interval [CI], 16.7 to 26.1) for lazertinib and 9.6 months (95% CI, 8.2 to 12.3) for gefitinib (hazard ratio [HR], 0.41; 95% CI, 0.28 to 0.60). This was supported by PFS analysis based on blinded independent central review. Significant PFS benefit with lazertinib was consistently observed across predefined subgroups, including patients with BM (HR, 0.28; 95% CI, 0.15 to 0.53) and those with L858R mutations (HR, 0.36; 95% CI, 0.20 to 0.63). Lazertinib safety data were consistent with its previously reported safety profile. Common adverse events (AEs) in both groups included rash, pruritus, and diarrhoea. Numerically fewer severe AEs and severe treatment–related AEs occurred with lazertinib than gefitinib. Conclusion Consistent with results for the overall LASER301 population, this analysis showed significant PFS benefit with lazertinib versus gefitinib with comparable safety in Korean patients with untreated EGFRm NSCLC, supporting lazertinib as a new potential treatment option for this patient population.

Background: Neutrophilic inflammation is a characteristic feature of idiopathic pulmonary fibrosis (IPF). S100 calcium-binding protein A9 (S100A9) is a neutrophil-derived protein involved in the development of neutrophil-related chronic inflammatory disorders. However, the role of S100A9 in IPF remains unclear. Methods: We used enzyme-linked immunosorbent assays to measure S100A9 levels in bronchoalveolar lavage fluid (BALF) and serum obtained from healthy controls (HCs) and patients with IPF, non-specific interstitial pneumonia, hypersensitivity pneumonitis, and sarcoidosis. Results: Compared with HCs, BALF S100A9 levels were significantly higher in IPF patients (P < 0.001), patients with hypersensitivity pneumonitis (P = 0.043), and patients with nonspecific interstitial pneumonia (P < 0.001). The S100A9 level in BALF of 0.093 ng/mL could distinguish IPF patients from HCs, with a specificity of 78.8% and a sensitivity of 81.6%. Similarly, the S100A9 level in BALF of 0.239 ng/mL had a specificity of 64.7% and a sensitivity of 66.7% for distinguishing IPF patients from patients with other interstitial lung diseases. Additionally, BALF S100A9 levels were significantly correlated with neutrophil counts (r = 0.356, P < 0.001) in BALF. IPF patients with S100A9 levels in BALF > 0.533 ng/ mL had lower survival rates, compared with patients who had levels ≤ 0.553 ng/mL (n = 49; hazard ratio [HR], 3.62; P = 0.021). Combination analysis revealed that IPF patients with S100A9 levels in BALF> 0.553 ng/mL or neutrophil percentages > 49.1% (n = 43) had significantly lower survival rates than patients with S100A9 levels in BALF ≤ 0.553 ng/mL and neutrophil percentages ≤ 49.1% (n = 41) (HR, 3.91; P = 0.014). Additionally, patients with serum S100A9 levels > 0.077 ng/mL (n = 29) had significantly lower survival rates than patients with levels ≤ 0.077 ng/mL (n = 53, HR, 2.52; P = 0.013). S100A9 was expressed on neutrophils and macrophages in BALF from IPF patients as well as α-smooth muscle actin positive cells in the lung tissues. Conclusion S100A9 is involved in the development and progression of IPF. Moreover, S100A9 levels in BALF and serum may be surrogate markers for IPF diagnosis and survival prediction, particularly when analyzed in combination with neutrophil percentages.

This study aimed to evaluate the differences in the baseline characteristics and patterns of antibiotic usage among hospitals based on their participation in the Korea National Antimicrobial Use Analysis System (KONAS). We obtained claims data from the National Health Insurance for inpatients admitted to all secondary- and tertiary-care hospitals between January 2020 and December 2021 in Korea. 15.9% (58/395) of hospitals were KONAS participants, among which the proportion of hospitals with > 900 beds (31.0% vs.2.6%, P < 0.001) and tertiary care (50.0% vs. 5.2%, P < 0.001) was higher than that among non-participants. The consumption of antibiotics targeting antimicrobial-resistant gram positive bacteria (33.7 vs. 27.1 days of therapy [DOT]/1,000 patient-days, P = 0.019) and antibiotics predominantly used for resistant gram-negative bacteria (4.8 vs. 3.7 DOT/1,000 patient-days, P = 0.034) was higher in KONAS-participating versus -non-participating hospitals. The current KONAS data do not fully represent all secondary- and tertiary-care hospitals in Korea; thus, the KONAS results should be interpreted with caution.

A reduced estimated glomerular filtration rate (eGFR) is a predictor for mortality in patients with acute myocardial infarction (AMI). This study aimed to compare mortality according to the GFR and eGFR calculation methods during long-term clinical follow-ups. Using the Korean Acute Myocardial Infarction Registry-National Institutes of Health Data, 13,021 patients with AMI were included in this study. Patients were divided into the surviving (n=11,503, 88.3%) and deceased (n=1,518, 11.7%) groups.Clinical characteristics, cardiovascular risk factors, and 3-year mortality-related factors were analyzed. eGFR was calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) and Modification of Diet in Renal Disease (MDRD) equations. The surviving group was younger than the deceased group (62.6±12.4 vs. 73.6±10.5 years, p＜0.001), whereas the deceased group had higher hypertension and diabetes prevalences than the surviving group. A high Killip class was more frequently observed in the deceased group. eGFR was significantly lower in the deceased group (82.2±24.1 vs. 55.2±28.6 ml/min/1.73 m 2 , p＜0.001). Multivariate analysis revealed that low eGFR was an independent risk factor for mortality during the 3-year follow-up. The CKD-EPI equation was more useful for predicting mortality than the MDRD equation (0.766; 95% confidence interval [CI], 0.753-0.779 vs. 0.738; 95% CI, 0.724-0.753; p=0.001). Decreased renal function was a significant predictor of mortality after 3 years in patients with AMI. The CKD-EPI equation was more useful for predicting mortality than the MDRD equation.

Osteoporosis and osteoporotic fractures cause socioeconomic concerns, and medical system and policies appear insufficient to prepare for these issues in Korea, where the older adult population is rapidly increasing. Many countries around the world are already responding to osteoporosis and osteoporotic fractures by adopting fracture liaison service (FLS), and such an attempt has only begun in Korea. In this article, we introduce the operation methods for institutions implementing FLS and characteristics of services, and activities of the FLS Committee for FLS implementation in the Korean Society for Bone and Mineral Research. In addition, we hope that the current position statement will contribute to the implementation of FLS in Korea and impel policy changes to enable a multidisciplinary and integrated FLS operated under the medical system.

Purpose: The purpose of this study was to identify the effects of case-based learning based on flipped learning in a pathophysiology course for nursing students. Methods: Participants were sophomore nursing students enrolled in a pathophysiology course. The experimental group (n=42) received the case-based learning in class after similar case-based learning in a pre-class based on flipped learning, while the control group (n=39) received the usual flipped learning. Data were analyzed by χ2-test, independent t-test, and ANCOVA using SPSS WIN 21.0. Results: There were significant differences in self-directed learning ability (F=10.93, p=.001), self-efficacy (F=5.45, p=.022), problem-solving ability (F=6.11, p=.016), and critical thinking disposition (F=6.76, p=.011) between the experimental group and the control group. Conclusion The application of case-based learning based on flipped learning in a pathophysiology course for nursing students was effective in improving problem-solving and self-directed learning abilities, self-efficacy, and the critical thinking disposition of sophomore nursing students.

Purpose: The purpose of this study was to identify the effects of case-based learning based on flipped learning in a pathophysiology course for nursing students. Methods: Participants were sophomore nursing students enrolled in a pathophysiology course. The experimental group (n=42) received the case-based learning in class after similar case-based learning in a pre-class based on flipped learning, while the control group (n=39) received the usual flipped learning. Data were analyzed by χ2-test, independent t-test, and ANCOVA using SPSS WIN 21.0. Results: There were significant differences in self-directed learning ability (F=10.93, p=.001), self-efficacy (F=5.45, p=.022), problem-solving ability (F=6.11, p=.016), and critical thinking disposition (F=6.76, p=.011) between the experimental group and the control group. Conclusion The application of case-based learning based on flipped learning in a pathophysiology course for nursing students was effective in improving problem-solving and self-directed learning abilities, self-efficacy, and the critical thinking disposition of sophomore nursing students.

Objective: The emergency medical service (EMS) is expected to improve the prognosis of patients suffering from acutemyocardial infarction (AMI). We investigated the impact of utilizing EMS on the clinical outcomes of AMI patients. Methods: From November 2011 to November 2015, a total of 13,102 patients in the Korea Acute Myocardial InfarctionRegistry-National Institute of Health (KAMIR-NIH) registry were enrolled. Patients were divided into two groups: the EMSgroup, first medical contact (FMC) with 119; the non-EMS group, the FMC at local hospitals that were not available forpercutaneous coronary intervention. The authors analyzed the mortality and major adverse cardiac and cerebrovascularevents during one-year of clinical follow-up. Results: A total of 8,863 patients were finally analyzed for this study, and a total of 1,999 patients (22.6%) utilized theEMS as FMC. The patients utilizing EMS were more frequently diagnosed with ST-segment elevation AMI. At presentation,the EMS group had a higher incidence of Killip class IV, and they had a shorter symptom-to-door time than non-EMS group. The patients utilizing EMS had higher incidence of peri-procedural complications and in-hospital mortality.The multivariate logistic regression analysis with backward elimination revealed that utilizing EMS is an independent factorfor predicting lower one-year mortality. Conclusion This study has demonstrated that the high-risk AMI patients can utilize the EMS in Korea. The EMS grouphas more favorable clinical outcome during one-year follow-up after discharge than the non-EMS group, whereas it had ahigher rate of death during hospitalization compared with that of the non-EMS group.

Chronic spontaneous urticaria (CSU) is defined as the occurrence of spontaneous wheals, angioedema, or both for >6 weeks in the absence of specific causes. It is a common condition associated with substantial disease burden both for affected individuals and societies in many countries, including Korea. CSU frequently persists for several years and requires high-intensity treatment; therefore, patients experience deteriorations in quality of life and medication-associated complications. During the last decade, there have been major advances in the pharmacological treatment of CSU and there is an outstanding need for evidence-based guidelines that reflect clinical practice in Korea. The guidelines reported here represent a joint initiative of the Korean Academy of Asthma, Allergy and Clinical Immunology and the Korean Dermatological Association, and aim to provide evidence-based guidance for the management of CSU in Korean adults and children. In Part 1, disease definition, guideline scope and development methodology as well as evidence-based recommendations on the use of antihistamines and corticosteroids are summarized.

Background/Aims: Many patients with acute myocardial infarction (AMI) suffer from heart failure due to progressive ischemic left ventricular (LV) remodeling. This study investigated the predictors of ischemic cardiomyopathy (ICMP) in patients with AMI who underwent successful percutaneous intervention. Methods: A total of 547 patients with AMI were divided into two groups: ICMP (n = 66, 67.1 ± 11.9 years, 78.8% males) and non-ICMP (n = 481, 62.5 ± 12.2 years, 70.1% males). Results: On echocardiography, the LVEF was significantly decreased (41.7 ± 10.5 vs. 55.4 ± 10.3%, p < 0.001) but the LV end-diastolic (54.1 ± 7.2 vs. 49.3 ± 5.3 mm, p < 0.001) and systolic (42.1 ± 8.0 vs. 33.5 ± 6.0 mm, p < 0.001) dimensions significantly increased in the ICMP group compared with the non-ICMP group. According to multivariate logistic regression analysis, LVEF < 50% (odds ratio [OR] 8.722, 95% confidence interval [CI] 2.986–25.478, p < 0.001), LV end-diastolic dimension > 55 mm (OR 4.511, 95% CI 1.561–13.038, p = 0.005), and ratio of early mitral inflow velocity to mitral annular early diastolic velocity (E/e’) ≥ 15 (OR 3.270, 95% CI 1.168–9.155, p = 0.024) were independent predictors of ICMP development. Conclusions The present study demonstrates that a larger LV size, lower LV function, and increased E/e’ (≥ 15) were independent predictors of ICMP. Therefore, the development of ICMP should be carefully monitored in AMI patients with these features.