Isolated respiratory tract microorganisms and clinical characteristics in asthma exacerbation of obese patients: a multicenter study.

Background: Viral infection is a risk factor for asthma exacerbation (AE). However, bacterial infections related to AE in adults are poorly known. On the other hand, obese patients with asthma have their own clinical and biological characteristics compared with non-obese patients.

Risk of loss to follow-up among tuberculosis patients in South Korea: whom should we focus on?

Introduction: In South Korea, public-private mix (PPM) has been a key strategy in national tuberculosis (TB) control program. This study aimed to identify rate of loss to follow-up (LTFU) among TB patients in nationwide PPM institutions and their risk factors.

Methods: A nationwide prospective observational study including drug susceptible TB patients diagnosed from the 1st day to the 10th day of every month between July 2018 and December 2020 in PPM institutions was designed.

Snoring might be a warning sign for metabolic syndrome in nonobese Korean women.

Metabolic syndrome (MetS) is an underlying cause of various diseases and is strongly associated with mortality. In particular, it has been steadily increasing along with changes in diet and lifestyle habits. The close relationship between sleep apnea and MetS is well established.

An Open-Label, Multicentre, Observational, Post-Marketing Study to Monitor the Safety and Effectiveness of Umeclidinium/Vilanterol in Korean Patients.

Background: Umeclidinium/vilanterol (UMEC/VI; ANORO ELLIPTA, GSK) is a commonly used dual bronchodilator. This study evaluated the safety and effectiveness of UMEC/VI in Korean patients with chronic obstructive pulmonary disease (COPD) over a 6-year period.

Methods: This was an open-label, multicentre, observational, post-marketing surveillance study.

Impact of COPD Treatment on Survival in Patients with Advanced Non-Small Cell Lung Cancer.

Chronic obstructive pulmonary disease (COPD) is associated with a poor prognosis in patients with non-small cell lung cancer (NSCLC). However, the impact of COPD treatment on the survival of patients with advanced NSCLC remains uncertain. We retrospectively investigated COPD patients among patients newly diagnosed with advanced NSCLC between September 2005 and August 2019 at a university hospital.

The Associations of Tonsillectomy with Adenoidectomy with Pneumonia and Appendicitis Based on National Sample Cohort Data from the Korean National Health Insurance Service.

 The association between tonsillectomy with adenoidectomy (T&A) with appendicitis is controversial, and the association of T&A with pneumonia has not been investigated.  To investigate the associations of T&A with pneumonia and appendicitis using data from the Korean National Health Insurance Service National Sample Cohort.  We selected patients between the ages of 3 and 10 years who had undergone T&A in 2005 and were monitored since the performance of the T&A until 2013.

Sarcoid-Like Reaction after Complete Remission of Malignancy: CT and F-FDG PET/CT Features for the Differential Diagnosis from Lymph Node Metastasis.

Purpose: To identify the imaging features indicative of sarcoid-like reactions in patients with intrathoracic lymphadenopathy after complete remission of malignancies.

Materials And Methods: This study enrolled five patients with histopathologically confirmed sarcoid-like reactions that developed after cancer remission. The clinical features and findings of CT and F-fluorodeoxyglucose (FDG) PET/CT were assessed.

Prediction of the risk of developing hepatocellular carcinoma in health screening examinees: a Korean cohort study.

Background: Almost all Koreans are covered by mandatory national health insurance and are required to undergo health screening at least once every 2 years. We aimed to develop a machine learning model to predict the risk of developing hepatocellular carcinoma (HCC) based on the screening results and insurance claim data.

Methods: The National Health Insurance Service-National Health Screening database was used for this study (NHIS-2020-2-146).

Incidence of Olfactory Dysfunction and Associated Factors: A Nationwide Cohort Study From South Korea.

Objectives: Olfactory dysfunction, a reduced or complete loss of the ability to smell, is gaining attention because of its substantial impact on an individual's quality of life and the possibility that it is an important sign of underlying disease. However, olfactory dysfunction is underdiagnosed in the general population due to diagnostic difficulty and unpredictable prognosis. This study aimed to evaluate the prevalence of clinically diagnosed olfactory dysfunction in South Korea by using well-organized, nationwide, population-based cohort data, and the associations between olfactory dysfunction and risk of neurodegenerative disorders.

Clinical characteristics and outcomes among older nursing home residents hospitalized with pneumonia.

Background: Due to population aging, the number of cases of pneumonia in nursing homes in South Korea has been increasing. This study investigated the characteristics and clinical outcomes in nursing home residents with pneumonia admitted to a tertiary hospital.

Methods: A retrospective cohort study was conducted of patients transferred to the tertiary hospital from nursing homes between August 2009 and October 2016.

Comparison of epidermal growth factor receptor tyrosine kinase inhibitors for patients with lung adenocarcinoma harboring different epidermal growth factor receptor mutation types.

Background: Epidermal growth factor receptor (EGFR) mutations in non-small-cell lung cancer predict sensitivity to EGFR tyrosine kinase inhibitors (TKIs). EGFR mutation types are associated with efficacy of EGFR TKIs. We investigated the clinical outcomes of afatinib, erlotinib, and gefitinib according to EGFR mutation type in patients with lung adenocarcinoma.

Does Diabetes Increase the Risk of Contracting COVID-19? A Population-Based Study in Korea.

Background: This study aimed to determine the infection risk of coronavirus disease 2019 (COVID-19) in patients with diabetes (according to treatment method).

Methods: Claimed subjects to the Korean National Health Insurance claims database diagnosed with COVID-19 were included. Ten thousand sixty-nine patients with COVID-19 between January 28 and April 5, 2020, were included.

Machine learning prediction for mortality of patients diagnosed with COVID-19: a nationwide Korean cohort study.

The rapid spread of COVID-19 has resulted in the shortage of medical resources, which necessitates accurate prognosis prediction to triage patients effectively. This study used the nationwide cohort of South Korea to develop a machine learning model to predict prognosis based on sociodemographic and medical information. Of 10,237 COVID-19 patients, 228 (2.

The effect of tonsillectomy with adenoidectomy on medical services used in association with otitis media based on Korean national sample cohort data.

Background: The effect of tonsillectomy with adenoidectomy (T&A) on otitis media has been investigated, but there have been no reports of the relationship between T&A and medical services used in association with otitis media. We investigated the effect of T&A on otitis media with regard to the number and cost of medical services used.

Methods: From the National Health Insurance Service National Sample Cohort data in Korea, we selected patients 7 years old or younger in 2002 who had T&A in 2005 while between the ages of three and ten.

Association between Body Mass Index and Risk of Coronavirus Disease 2019 (COVID-19): A Nationwide Case-control Study in South Korea.

Background: Increased body mass index (BMI) has been associated with a higher risk of severe coronavirus disease 2019 (COVID-19) infections. However, whether obesity is a risk factor for contracting COVID-19 has hardly been investigated so far.

Methods: We examined the association between BMI level and the risk of COVID-19 infection in a nationwide case-control study comprised of 3788 case patients confirmed to have COVID-19 between 24 January and 9 April 2020 and 15 152 controls matched by age and sex, who were aged 20 years or more and underwent National Health Insurance Service (NHIS) health examinations between 2015-2017, using data from the Korean NHIS with linkage to the Korea Centers for Disease Control and Prevention data.

Clinical impact of pre-hypertension on the risk of cancer in male and female subjects.

There are few studies assessing pre-hypertension and an impaired fasting glucose (IFG) and their combined effects on the cancer risk. We investigated the impact of pre-hypertension on cancer risk and IFG, and their combined effects on the cancer risk. This study included 371,762 subjects (≥40 years) who had never been diagnosed with hypertension, diabetes mellitus (DM), and cancer before.

Diagnostic yield of additional conventional transbronchial lung biopsy following radial endobronchial ultrasound lung biopsy for peripheral pulmonary lesions.

Background: Radial endobronchial ultrasound (R-EBUS) transbronchial lung biopsy (TBLB) improves the diagnostic yield from peripheral pulmonary lesions (PPLs). However, the small specimens obtained using small forceps through a guide sheath (GS) may impede diagnosis and molecular analysis. Here, we investigated the diagnostic significance of additional conventional TBLB with standard forceps after R-EBUS-GS-guided TBLB.

Clinical significance of EGFR mutation types in lung adenocarcinoma: A multi-centre Korean study.

Adenocarcinoma is the most common type of non-small cell lung cancer. Some causative genomic alterations in epidermal growth factor receptor (EGFR), including deletions in exon 19 (E19 dels) and a point mutation in E21, are known to have favourable prognoses due to sensitivity to tyrosine kinase inhibitors; however, the prognoses of other uncommon mutations are unclear. This study analysed the clinical significance of EGFR mutation types in lung adenocarcinoma.

Inhaled Corticosteroids in Asthma and the Risk of Pneumonia.

Purpose: Asthma is a common disease that is expensive and burdensome for patients. Inhaled corticosteroids (ICS) are the most important drugs for asthma treatment and are often prescribed long-term. However, the use of ICS has been reported to increase pneumonia, though this remains controversial.

Clinical profiles of early and tuberculosis-related mortality in South Korea between 2015 and 2017: a cross-sectional study.

Background: Although the incidence of tuberculosis (TB) has decreased in South Korea, the mortality rate remains high. TB mortality is a key indicator for TB control interventions. The purpose of this study was to assess early and TB-related mortality during anti-TB treatment and describe the associated clinical characteristics.

Hemoptysis requiring bronchial artery embolization in patients with nontuberculous mycobacterial lung disease.

Background: Although infections caused by nontuberculous mycobacteria (NTM) are increasing in prevalence, there are few data about hemoptysis in patients with NTM lung disease. This study investigated the characteristics and prognosis of hemoptysis secondary to NTM infection.

Methods: Following a retrospective review of cases managed between 2006 and 2016, 183 patients with NTM lung disease were enrolled and analyzed.

Risk factors associated with an increase in the size of ground-glass lung nodules on chest computed tomography.

Background: The detection rate of ground-glass nodules (GGNs) in the lung has increased with the increased use of low-dose computed tomography (CT) of the chest for cancer screening; however, limited data is available on the natural history, follow-up, and treatment of GGNs. The aim of this study was to identify factors associated with an increase in the size of GGNs.

Methods: A total of 338 patients (mean ages, 59.