Pretreatment Neutrophil-to-Lymphocyte Ratio and Smoking History as Prognostic Factors in Advanced Non-Small Cell Lung Cancer Patients Treated with Osimertinib.

Background: The remarkable efficacy of osimertinib in non‒small cell lung cancer (NSCLC) with acquired T790M mutation has been widely documented in clinical trials and real-world practice. However, some patients show primary resistance to this drug. Even patients who initially show a favorable response have inconsistent clinical outcomes later.

Effects of exposure to ambient air pollution on pulmonary function impairment in Korea: the 2007-2017 Korea National Health and Nutritional Examination Survey.

Objectives: This study aimed to investigate the association between pulmonary function and air pollution using 2007-2017 data from the Korea National Health and Nutrition Examination Survey, a nationwide cross-sectional representative survey.

Methods: A total of 27,378 participants that had sampling weights from a complex sample survey were included in this study. Using the data for forced expiratory volume in 1 second and forced vital capacity, the participants with pulmonary function impairment were classified according to the criteria of restrictive lung disease and chronic obstructive pulmonary disease (COPD).

Impact of COVID-19 on TB epidemiology in South Korea.

Five referral hospitals, South Korea. To assess epidemiological changes in TB before and during the COVID-19 pandemic. This was a multicentre cohort study of 3,969 patients diagnosed with TB.

Korean physician prescription patterns for home oxygen therapy in chronic obstructive pulmonary disease patients.

Background/aims: Hypoxemia in chronic obstructive pulmonary disease (COPD) leads to reduced ability to exercise, decreased quality of life, and, eventually, increased mortality. Home oxygen therapy in patients with severe COPD reduces distress symptoms and mortality rates. However, there have been few studies on physicians' prescription behavior toward home oxygen therapy.

Plasma concentrations of NOX4 are predictive of successful liberation from mechanical ventilation and 28-day mortality in intubated patients.

Background: Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX) enzymes play important roles in generating reactive oxygen species (ROS); in particular, NOX4 plays a distinct role in regulating lung inflammation and apoptosis.

Methods: We determined whether plasma NOX4 level can be used as a prognostic biomarker to guide weaning from mechanical ventilation and to predict mortality in intubated patients. Plasma levels of NOX4 were measured at days 1 (NOX4 D1) and 7 (NOX4 D7) after initiation of mechanical ventilation in 184 patients.

Risk factors for early readmission after acute exacerbation of chronic obstructive pulmonary disease.

Background And Aims: Patients discharged after treatment for acute exacerbation of chronic obstructive pulmonary disease (COPD) are at high risk for readmission. We aimed to identify the prevalence and risk factors for readmission.

Methods: We included 16,105 patients who had claimed their medical expenses from 1 May 2014 to 1 May 2016 after discharge from any medical facility in Korea, following treatment for acute exacerbation of COPD.

Pro-cathepsin D as a diagnostic marker in differentiating malignant from benign pleural effusion: a retrospective cohort study.

Background: Malignant pleural effusion (MPE) causes substantial symptomatic burden in advanced malignancy. Although pleural fluid cytology is a commonly accepted gold standard of diagnosis, its low diagnostic yield is a challenge for clinicians. The aim of this study was to determine whether pro-cathepsin D can serve as a novel biomarker to discriminate between MPE and benign pleural effusion (BPE).

Relationship Between Changes in Inhalation Treatment Level and Exacerbation of Chronic Obstructive Pulmonary Disease: Nationwide the Health Insurance and Assessment Service Database.

Background And Objective: Maintaining adequacy in chronic obstructive pulmonary disease (COPD) care is essential to sustain an adequate level of care. We aimed to assess the current status of COPD quality control and the influence of inhaler changes on disease-related health care utilization.

Methods: The Health Insurance Review and Assessment Service (HIRA) nationwide database for reimbursed insurance claims from all medical institutions in South Korea from May 2014 to April 2017 was investigated.

Cut-off value of FEV1/FEV6 to determine airflow limitation using handheld spirometry in subjects with risk of chronic obstructive pulmonary disease.

Background/aims: Postbronchodilator forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) less than 0.7 using spirometry is the golden standard to diagnose airf low limitation of chronic obstructive pulmonary disease (COPD). Recently, measuring FEV6 has been suggested as an alternative to measure FVC.

Activation of Transient Receptor Potential Melastatin Family Member 8 (TRPM8) Receptors Induces Proinflammatory Cytokine Expressions in Bronchial Epithelial Cells.

Purpose: Cold air is a major environmental factor that exacerbates asthma. Transient receptor potential melastatin family member 8 (TRPM8) is a cold-sensing channel expressed in the airway epithelium. However, its role in airway inflammation remains unknown.

Development and Validation of a Quick Sepsis-Related Organ Failure Assessment-Based Machine-Learning Model for Mortality Prediction in Patients with Suspected Infection in the Emergency Department.

The quick sepsis-related organ failure assessment (qSOFA) score has been introduced to predict the likelihood of organ dysfunction in patients with suspected infection. We hypothesized that machine-learning models using qSOFA variables for predicting three-day mortality would provide better accuracy than the qSOFA score in the emergency department (ED). Between January 2016 and December 2018, the medical records of patients aged over 18 years with suspected infection were retrospectively obtained from four EDs in Korea.

The Dynamics of Respiratory Microbiota during Mechanical Ventilation in Patients with Pneumonia.

Bacterial pneumonia is a major cause of mechanical ventilation in intensive care units. We hypothesized that the presence of particular microbiota in endotracheal tube aspirates during the course of intubation was associated with clinical outcomes such as extubation failure or 28-day mortality. Sixty mechanically ventilated ICU (intensive care unit) patients (41 patients with pneumonia and 19 patients without pneumonia) were included, and tracheal aspirates were obtained on days 1, 3, and 7.

Metabolic Syndrome in Early Chronic Obstructive Pulmonary Disease: Gender Differences and Impact on Exacerbation and Medical Costs.

Background: Metabolic syndrome (MetS) is a well-known comorbidity of chronic obstructive pulmonary disease (COPD). However, their interrelationship, particularly in early COPD, remains unclear. Therefore, we aimed to assess the prevalence and clinical characteristics of MetS in patients with early COPD, and to explore the impact of MetS on the frequency of COPD exacerbations and associated medical costs.

Thyroid transcription factor-1 as a prognostic indicator for stage IV lung adenocarcinoma with and without EGFR-sensitizing mutations.

Background: Thyroid transcription factor (TTF)-1 expression is a diagnostic marker and a good prognostic indicator for lung adenocarcinoma. However, its good prognostic ability might be due to epidermal growth factor receptor (EGFR)-sensitizing mutations as shown by the positive correlation between TTF-1 expression and EGFR mutations. We explored the prognostic impact of TTF-1 expression according to EGFR-sensitizing mutation status in lung adenocarcinoma patients.

Korean Guidelines for Diagnosis and Management of Interstitial Lung Diseases: Part 2. Idiopathic Pulmonary Fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive fibrosing interstitial pneumonia, which presents with a progressive worsening dyspnea, and thus a poor outcome. The members of the Korean Academy of Tuberculosis and Respiratory Diseases as well as the participating members of the Korea Interstitial Lung Disease Study Group drafted this clinical practice guideline for IPF management. This guideline includes a wide range of topics, including the epidemiology, pathogenesis, risk factors, clinical features, diagnosis, treatment, prognosis, and acute exacerbation of IPF in Korea.

Levels of vitamin D-associated cytokines distinguish between active and latent tuberculosis following a tuberculosis outbreak.

Background: Vitamin D levels are associated with the extent of mycobactericidal activity. Interleukin (IL)-15 and IL-32 play roles in the vitamin D-mediated tuberculosis (TB) defense mechanism. Vitamin D induces IL-1β, which plays an important role in terms of resistance to TB.

Comparison of clinical efficacy between ultra-LABAs and ultra-LAMAs in COPD: a systemic review with meta-analysis of randomized controlled trials.

Background: A single long-acting bronchodilator, ultra-long acting muscarinic antagonist (ultra-LAMA) or ultra-long acting β-agonist (ultra-LABA) is preferred for the initial treatment of patients with chronic obstructive pulmonary disease (COPD); however, there are few head-to-head comparative studies between the two. Here, a meta-analysis of randomized controlled trials was performed to compare the clinical efficacy between ultra-LABA and ultra-LAMA in patients with moderate-to-severe COPD.

Methods: MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were searched (to March 1, 2017) to identify all published randomized controlled trials.

Male current smokers have low awareness and optimistic bias about COPD: field survey results about COPD in Korea.

Background: Smoking is a major risk factor for COPD. However, there is low COPD awareness among smokers. We conducted a field survey to investigate COPD awareness, optimistic bias associated with COPD, and COPD prevalence (using handheld spirometry) among current male smokers.

Inhibition of NADPH Oxidase 4 (NOX4) Signaling Attenuates Tuberculous Pleural Fibrosis.

Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase [NOX] enzymes serve several hemostatic and host defense functions in various lung diseases, but the role of NOX4 signaling in tuberculous pleurisy is not well understood. The role of NOX4 signaling in tuberculous pleural fibrosis was studied using invitro pleural mesothelial cell (PMC) experiments and a murine model of bacillus Calmette⁻Guérin (BCG) pleural infection. The production of NOX4 reactive oxygen species (NOX4⁻ROS) and the epithelial mesenchymal transition (EMT) in PMCs were both induced by heat-killed mycobacterium tuberculosis (HKMT).

Efficacy and predictors of response to inhaled corticosteroid treatment for chronic cough.

Background/aims: Inhaled corticosteroids (ICS) are a treatment of choice for eosinophilic airway diseases, but their efficacy for other causes of chronic cough is controversial.

Methods: We conducted a prospective observational study to determine the ICS efficacy and clinical predictors of response to ICS in patients with upper airway cough syndrome (UACS) or unexplained chronic cough (UCC). Sixty-eight patients with UACS and 33 patients with UCC (duration of cough ≥ 8 weeks) were treated with ICS: 250 µg of fluticasone propionate or 400 µg of budesonide twice a day at physician's discretion.

Correlation of microbiological yield with radiographic activity on chest computed tomography in cases of suspected pulmonary tuberculosis.

Background: Little is known about the correlation between microbiological yield and radiographic activity, on chest computed tomography (CT), in suspected pulmonary tuberculosis (PTB) cases, despite CT being widely used, clinically.

Methods: We used multicenter retrospective data, obtained from medical records, focusing on the diagnostic performance for definite PTB. We categorized patients into four groups, by radiographic activity: definitely active, probably active, indeterminate activity, and probably inactive.

Favorable longitudinal change of lung function in patients with asthma-COPD overlap from a COPD cohort.

Background: The recognition of asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) as a distinct phenotype of COPD or asthma has increased. Although ACO has worse clinical features than non-ACO COPD, limited information is available on long-term outcomes of lung function decline for ACO and non-ACO COPD.

Methods: COPD patients with at least 3 years of follow-up were selected from the Korean Obstructive Lung Disease cohort.