Impact of bronchitis variability on outcomes of COPD.

Objective: This study aimed to evaluate the impact of serial bronchitic status over two consecutive years on clinical outcomes, including frequency of exacerbation and lung function decline rate.

Methods: We analysed data from 1265 participants enrolled in the Korea COPD Subgroup Study, a nationwide prospective observational chronic obstructive pulmonary disease (COPD) cohort. Bronchitic status was determined using subquestionnaires of the COPD Assessment Test at baseline and after 1 year, classifying patients into three serial bronchitic groups of persistently not bronchitic (NB), intermittently bronchitic (IB) and chronic bronchitis (CB).

Efficacy and safety of HL-301 compared with erdosteine in acute bronchitis: a randomized, double-blind, non-inferiority trial.

Background/aims: This study evaluated the non-inferiority of HL-301 to erdosteine in terms of symptom relief and the anti- inflammatory effects in acute bronchitis patients not treated with antibiotics.

Methods: In a double-blind, non-inferiority trial, patients were randomized 1:1 to receive either HL-301 (300 mg twice daily) or erdosteine (300 mg three times daily) for seven days. The primary endpoint was change in total Bronchitis Severity Score (BSS) from baseline to day 7.

Factors Associated with Exertional Desaturation in Patients with Chronic Obstructive Pulmonary Disease.

The six minute walk test (6MWT) has a prognostic role in patients with chronic obstructive pulmonary disease (COPD). The aim of this study was to determine the factors associated with desaturation during the 6MWT in patients with COPD. This study utilized data from the prospective KOrea COPD Subgroup Study (KOCOSS) cohort.

Effects of Triple Therapy on the Clinical Course of Non-Eosinophilic COPD Groups B.

Background: Although the efficacy of triple therapy in treating chronic obstructive pulmonary disease (COPD) patients with a history of exacerbation is well established in groups with frequent exacerbations, less research has been conducted on its use in group B. Here, we investigated the effects of triple therapy on COPD patients with low eosinophil counts in the context of the current management of group B.

Methods: Using data from the Korean COPD Subtype Study (KOCOSS), we selected patients with blood eosinophil count (BEC) less than 300 cells/μL as non-eosinophilic COPD groups.

Development of a Scoring System to Predict Suboptimal Peak Inspiratory Flow in Patients With Chronic Obstructive Pulmonary Disease.

Background: Peak inspiratory flow rate (PIFR) is a critical indicator for the successful use of dry powder inhalers (DPIs). However, resource constraints often limit the practicality of measuring PIFR prior to DPI prescription.

Methods: A cross-sectional observational study was conducted across seven hospitals in Korea, including patients with chronic obstructive pulmonary disease (COPD).

Impact of the Race-Neutral Equation on Mortality Risk Prediction in Korean Patients With Chronic Obstructive Pulmonary Disease.

Background And Objective: Recently, GLI-2022, a race-neutral reference equation, was proposed for spirometric interpretation. However, the impact of using the GLI-2022 in predicting mortality risk has not been fully investigated. This study determined whether the GOLD grades based on GLI-2022 or race-specific equations are overestimated or underestimated in terms of mortality risk prediction among Korean patients with COPD.

Chronic obstructive pulmonary disease is a risk factor for non-tuberculous mycobacterial pulmonary disease: a population-based matched cohort study.

Background: Longitudinal studies comprehensively evaluating the direction of the relationship between chronic obstructive pulmonary disease (COPD) and non-tuberculous mycobacterial pulmonary disease (NTM-PD) are scarce. Therefore, this study aimed to evaluate whether COPD influences the development of NTM-PD even after considering various confounders by using a nationwide longitudinal cohort study.

Methods: Data from the National Health Insurance Service National Sample Cohort between 2002 and 2019 were analysed.

Clinical characteristic of patients with COPD-A.

Background: The 2023 Global Initiative for Chronic Obstructive Lung Disease (GOLD) document proposed the COPD-A subtype as a condition of COPD with asthma. We examined the characteristics of COPD-A patients and analyzed them according to smoking history and inhaled corticosteroid (ICS) use.

Methods: Patients in the COPD cohort with a history of asthma were included.

Comparing Heterogenous Phenotypes of Chronic Obstructive Pulmonary Disease: Network Analysis and Penalized Generalized Linear Model.

Background And Objective: Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease, with chronic bronchitis (CB) and emphysema phenotypes. The aim of our study was to compare the distinct patterns of correlation networks for respiratory symptoms and predictors of future exacerbations of different COPD phenotypes.

Methods: CB and emphysema were identified using a questionnaire and computed tomography images, respectively, and also included patients with preserved ratio impaired spirometry (PRISm).

Epigenetic profiles integrated with transcriptomic reveal the difference between COPD and PRISm in KOCOSS-NIH.

In 2023, the Global Initiative for Chronic Obstructive Lung Disease (GOLD) introduced a provision regarding preserved ratio-impaired spirometry (PRISm), a presumed pre-stage of Chronic Obstructive Pulmonary Disease (COPD), into the COPD guidelines. However, further research in this area is needed. Our study aimed to investigate the epigenetic differences between PRISm and COPD.

Risk of acute exacerbation of chronic obstructive pulmonary disease after COVID-19 recovery: a nationwide population-based cohort study.

Background: Chronic obstructive pulmonary disease (COPD) is associated with severe Coronavirus disease 2019 (COVID-19) outcomes. However, it is uncertain whether the risk of acute exacerbation of COPD (AECOPD) increases after recovering from COVID-19.

Methods: This study included 2,118 individuals with COPD from the Korea National Health Insurance Service database who were also diagnosed with COVID-19.

The Efficacy and Safety of Pelubiprofen in the Treatment of Acute Upper Respiratory Tract Infection: A Multicenter, Randomized, Double-Blind, Non-Inferiority Phase III Clinical Trial Compared to Loxoprofen.

Acute upper respiratory tract infections (URTIs) are common illnesses that cause significant discomfort due to symptoms such as fever, headache, sore throat, and muscle pain. Non-steroidal anti-inflammatory drugs (NSAIDs) are widely used for symptom relief due to their anti-inflammatory, analgesic, and antipyretic properties. Pelubiprofen, a new NSAID, has not been extensively evaluated for its efficacy and safety in treating URTI-related symptoms, particularly fever.

Risk Factors of FEV₁/FVC Decline in COPD Patients.

Background: Factors influencing the decline in forced expiratory volume in one second (FEV₁)/forced vital capacity (FVC) for chronic obstructive pulmonary disease (COPD) progression remain uncertain. We aimed to identify risk factors associated with rapid FEV₁/FVC decline in patients with COPD.

Methods: This multi-center observational study was conducted from January 2012 to December 2022.

COVID-19 and risk of long-term mortality in COPD: a nationwide population-based cohort study.

Background: Chronic obstructive pulmonary disease (COPD) is a risk factor for severe COVID-19. However, mortality after COVID-19 recovery in this population remains unclear.

Methods: We retrospectively enrolled individuals with COPD from the Korean National Health Insurance database.

Kernel Conversion Improves the Correlation between the Extent of Emphysema and Clinical Parameters in Chronic Obstructive Pulmonary Disease: A Multicenter Cohort Study.

Background: Computed tomography (CT) scans are utilized to assess emphysema, a prominent phenotype of chronic obstructive pulmonary disease (COPD). Variability in CT protocols and equipment across hospitals can impact accuracy. This study aims to implement kernel conversion across different CT settings and evaluate changes in the correlation between the emphysema index pre- and post-kernel conversion, along with clinical measures in COPD patients.

COVID-19 and Long-term Risk of Ischemic Heart Disease in Asthma.

Despite the importance of comorbid ischemic heart disease (IHD) in the prognosis of asthma, the long-term impact of coronavirus disease 2019 (COVID-19) on IHD in adults with asthma remains unclear. This study investigated the long-term effects of COVID-19 on the risk of IHD in individuals with asthma, particularly regarding COVID-19 severity. Using the Korean National Health Insurance Service claims database, we identified individuals with asthma who had recovered from COVID-19 between October 8, 2020, and December 31, 2021 (n = 8,011) and 1:1 propensity score-matched controls (n = 8,011).

Blood eosinophil count and treatment patterns of chronic obstructive pulmonary disease patients in South Korea using real-world data.

Background/aims: Chronic obstructive pulmonary disease (COPD) management guidelines have increasingly emphasised the importance of exacerbation prevention, and the role of blood eosinophil count (BEC) as a biomarker for inhaled corticosteroids (ICS) response. This study aimed to describe the distribution and stability of BEC and understand real-world treatment patterns among COPD patients in South Korea.

Methods: This was a retrospective database analysis using data obtained from the KOrea COPD Subgroup Study (KOCOSS) registry between January 2012 and August 2018.

Impact of Multidrug-Resistant Bacterial Colonization on Clinical Characteristics, Antibiotic Treatment, and Clinical Outcomes of Hospital-Acquired Pneumonia.

Purpose: To determine effects of colonization with multidrug-resistant bacteria (MDRB) in general wards on characteristics, treatment, and prognosis of hospital-acquired pneumonia (HAP).

Methods: This was a multicenter retrospective cohort study of patients with HAP admitted to 16 tertiary or university hospitals in Korea from July 2019 to December 2019. From the entire cohort, patients who developed pneumonia in general wards with known colonization status before the onset of pneumonia were included in this study.

Clinical Significance of Various Pathogens Identified in Patients Experiencing Acute Exacerbations of COPD: A Multi-center Study in South Korea.

Background: Respiratory infections play a major role in acute exacerbation of chronic obstructive pulmonary disease (AECOPD). This study assessed the prevalence of bacterial and viral pathogens and their clinical impact on patients with AECOPD.

Methods: This retrospective study included 1,186 patients diagnosed with AECOPD at 28 hospitals in South Korea between 2015 and 2018.