Association between asthma and cardiovascular diseases: A longitudinal follow-up study using a national health screening cohort.

Background: Asthma has been suggested to be a risk factor for cardiovascular diseases (CVDs), although the evidence supporting this relationship is inconclusive. This study aimed to explore the long-term associations between asthma and asthma exacerbations with the occurrence of cardiovascular diseases (CVDs) such as ischemic heart disease (IHD), heart failure (HF), and cerebral stroke, utilizing data from a nationwide cohort. Materials and methods: This study utilized data from the Korean National Health Insurance Service-Health Screening Cohort database (2002-2015), including information on 111,316 asthma patients and an equal number of 1:1 matched control participants. A propensity score overlap-weighted Cox proportional hazards regression model was used to analyze the overlap-weighted hazard ratios (HRs) of asthma and exacerbated asthma for cardiovascular diseases (CVDs) within this cohort. Results: During the follow-up period, the incidence rate (IR) of IHD per 1000 person-years (PYs) was 7.82 in patients with asthma and 5.79 in controls. The IR of HF was 2.53 in asthmatic patients and 1.36 in controls. After adjustment for covariates, asthmatic patients exhibited 1.27-fold and 1.56-fold higher HRs for IHD (95% confidence interval (CI) = 1.23-1.37, P < 0.001) and HF (95% CI = 1.36-1.63, P < 0.001) than the controls, respectively. In addition, there was an increased HR for IHD and HF in the asthma exacerbation group compared with the nonexacerbated asthma group (adjusted HR, 1.29, 95% CI = 1.24-1.34, P < 0.001 for IHD and aHR 1.68, 95% CI = 1.58-1.79, P < 0.001 for HF). However, the occurrence of stroke was decreased in asthmatic patients compared with controls (aHR = 0.96, 95% CI = 0.93-0.99, P = 0.008). Conclusions: Adults with asthma are more likely to develop CVDs. Additionally, severe asthma exacerbations are significantly associated with an increased occurrence of CVDs.

Efficacy and safety of mixture of ivy leaf extract and coptidis rhizome in the treatment of acute bronchitis: multicenter, randomized, double-blinded, active-controlled, parallel, therapeutic confirmatory clinical trial.

BACKGROUND: Acute bronchitis is the most common respiratory disease. Mixture of Ivy Leaf Extract and Coptidis rhizome syrup has shown good treatment efficacy against chronic bronchitis and acute respiratory infections. This study aimed to evaluate the efficacy and safety of Mixture of Ivy Leaf Extract and Coptidis rhizome compared with those of Pelargonium sidoides extract, for the treatment of acute bronchitis. METHODS: We performed a multicenter, randomized, double-blind, active-controlled, parallel phase III study in 220 patients with acute bronchitis. The participants were offered either Mixture of Ivy Leaf Extract and Coptidis rhizome syrup (AGS) and placebo of P. sidoides tablet or placebo syrup and active tablet of P. sidoides (AGU) for 7 days. The primary endpoint was the change in the Bronchitis Severity Score (BSS) from the baseline visit (visit 2) to day 7 (visit 3). RESULTS: For the primary outcome, there was no significant difference in the change of total BSS between visits 2 and 3 (-4.10 ± 1.93 vs. -4.24 ± 1.85, p = 0.5125), and since the upper limit of the confidence interval (1.00) was smaller than the predetermined non-inferiority margin (1.17), it was confirmed that the AGS group was non-inferior to the AGU group. The changes in each symptom in the BSS between visits 2 and 3 also showed no significant differences. The overall improvement rate measured by the investigator (91.7 vs. 89.7%; p = 0.3506) and the satisfaction rate of the participants at visit 3 also showed no significant differences (97.2 vs. 94.4%; p = 0.4388). Regarding safety issues, adverse reactions were noted in both groups similarly, with no serious adverse events (4.55 vs. 3.64%, p > 0.999). CONCLUSION: Mixture of Ivy Leaf Extract and Coptidis rhizome syrup is as effective and safe as P. sidoides in controlling symptoms of acute bronchitis.

Application of the Lancet Commission COPD classification to COPD Cohort Population in South Korea.

The Lancet Commissions on COPD recommended a new classification based on five main risk factors. Patients with COPD were prospectively enrolled in a Korean COPD subgroup study cohort between April 2012 and June 2022. Patients were classified according to the etiologies (Type 1: Genetically determined (COPD-G), Type 2: Abnormal lung development (COPD-D), Type 3: Infections (COPD-I), Type 4: Cigarette smoking (COPD-C), Type 5: Biomass and pollution (COPD-P)). The database enrolled 3476 patients. Among 3392 patients, 52 (2 %), 1339 (39 %), 2930 (86 %), and 2221 (65 %) were compatible with type 2 (COPD-D), 3 (COPD-I), 4 (COPD-C), and 5 (COPD-P), respectively. Most patients (71 %, 2405) had multiple risk factors contributing to their COPD. However, 93, 712, and 182 patients had only type 3 (COPD-I), 4 (COPD-C), and 5 (COPD-P), respectively. Type 3 (COPD-I) only patients were significantly younger, more often female, and had lower lung function. Both the rate and frequency of severe exacerbations were significantly higher in type 3 (COPD-I) only patients (p = 0.038 and p = 0.048, respectively). Compared with type 5 (COPD-P) only, type 3 (COPD-I) only was significantly associated with the risk of severe exacerbation (Odds ratio, 5.7 [95 % CI, 1.0-32.4]; P = 0.049, incident rate ratio, 8.7 [95 % CI, 1.7-44.0]; P = 0.009). Many patients were affected by multiple factors. Therefore, it is important to consider not only smoking history, but also other potential risk factors when evaluating patients with COPD. Further research is needed to explore the implications of this new COPD classification system for clinical practice and treatment strategies.

Differential decline of lung function in COPD patients according to structural abnormality in chest CT.

Background: Different progressions or prognoses of chronic obstructive pulmonary disease (COPD) have been reported according to structural abnormalities based on chest computed tomography (CT). This study aimed to investigate whether different structural abnormalities independently affect annual lung function changes and clinical prognosis in patients with COPD. Methods: This longitudinal multicenter observational study was conducted using the KOCOSS cohort (NCT02800499) database in Korea from January 2012 to December 2019. For COPD patients with chest CT findings at baseline enrolment and longitudinal spirometric data, annual forced expiratory volume in 1 s (FEV1) decline rate (mL/year) and clinical outcomes were compared according to structural abnormalities, including emphysema, bronchiectasis (BE), and tuberculosis-destroyed lung (TDL). We estimated the adjusted annual FEV1 changes using a mixed-effect linear regression model. Results: Among the enrolled 237 patients, 152 showed structural abnormalities. Emphysema, BE, and TDL were observed in 119 (78.3%), 28 (18.4%), and 27 (17.8%) patients, respectively. The annual decline in FEV1 was faster in COPD patients with structural abnormalities than those without (ß = -70.6 mL/year, P-value = 0.039). BE/TDL-dominant or emphysema-dominant structural abnormality contributed to an accelerated annual FEV1 decline compared to no structural abnormality (BE/TDL-dominant, ß = -103.7 mL/year, P-value = 0.043; emphysema-dominant, ß = -84.1 mL/year, P-value = 0.018). Structural abnormalities made no significant differences in acute exacerbation rate and mortality. Conclusion: The lung function decline rate in COPD differed according to structural abnormalities on CT. These findings may suggest that more focus should be placed on earlier intervention or regular follow-up with spirometry in COPD patients with BE or TDL on chest CT.

Components of the Chronic Obstructive Pulmonary Disease Assessment Test Associated with the Exacerbation of Severe Chronic Obstructive Pulmonary Disease Patients.

INTRODUCTION: The chronic obstructive pulmonary disease (COPD) Assessment Test (CAT) score is widely used for evaluating the health status of patients diagnosed with COPD. The aim of this study was to identify which components of the CAT are associated with exacerbations in severe COPD patients. METHODS: Using data from the Korean COPD Subgroup Study (KOCOSS), we identified 3,440 COPD patients, among which 1,027 patients are classified as having severe COPD based on spirometry results. The CAT scores on 8 items were evaluated and classified into respiratory and non-respiratory categories. We analyzed the association between CAT item scores and moderate-to-severe exacerbations during study enrollment and the following years. RESULTS: Patients with a history of moderate-to-severe exacerbations had higher scores on non-respiratory CAT components. Longitudinal CAT scores on all items after enrollment were higher in the moderate-to-severe exacerbation group. Additionally, the frequency of severe exacerbations was associated with specific CAT components related to limited activities, confidence leaving home, sleeplessness, and energy. CONCLUSIONS: This study revealed that the non-respiratory CAT component scores were statistically significant factors for predicting the moderate-to-severe exacerbation of severe COPD patients. Non-respiratory symptoms and functional limitations should be considered in patients with severe COPD. Interventions, such as pulmonary rehabilitation, may be needed to improve patients' overall well-being and prevent exacerbations.

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. METHODS: We investigated the differences in isolated pathogens for AE between obese and non-obese patients with asthma. We included 407 patients with AE from 24 medical centers in Korea. Microorganisms isolated from culture, RT-PCR or serologic tests using lower respiratory tract specimens were retrospectively investigated. RESULTS: A total of 171 obese and 236 non-obese patients with asthma were included for analysis. Compared to non-obese patients, obese patients were associated with women (77.2% vs. 63.6%), never smoker (82.5% vs. 73.9%), shorter duration of asthma (7.9 ± 8.4 vs. 10.5 ± 10.1 years), less history of pulmonary tuberculosis (8.8% vs. 17.4%), and more comorbidity of allergic rhinitis (48.5% vs. 0.8%). Viral and/or bacterial infections were detected in 205 patients (50.4%) with AE. The numbers of patients with viral only, bacterial only, or both infections were 119, 49, and 37, respectively. The most commonly isolated bacterium was Streptococcus pneumoniae, followed by Pseudomonas aeruginosa and Chlamydia pneumoniae. Obese patients showed a lower incidence of Chlamydia pneumoniae infection. In the non-obese group, bacterial infection, especially Chlamydia pneumoniae infection, was significantly associated with the duration of systemic corticosteroid use (13.6 ± 19.8 vs. 9.7 ± 6.7 days, p = 0.049). CONCLUSION: Bacterial infection was associated with a longer period of corticosteroid use in the non-obese group. Acute Chlamydia pneumoniae infection was less associated with obese patients with AE. Further well-designed studies are needed to evaluate microorganisms and the efficacy of antibiotics in patients with AE.

Spirometric Interpretation and Clinical Relevance According to Different Reference Equations.

BACKGROUND: Global Lung Function Initiative (GLI)-2012 reference equation is currently suggested for interpretation of spirometry results and a new local reference equation has been developed in South Korea. However, lung function profiles according to the different reference equations and their clinical relevance have not been identified in chronic obstructive pulmonary disease (COPD) patients. METHODS: Our cross-sectional study evaluated Choi's, Korean National Health and National Examination Survey (KNHANES)-VI, and GLI-2012 reference equations. We estimated the percentages of predictive forced expiratory volume in one second (FEV1) and airflow limitation severity according to reference equations and analyzed their associations with patient reported outcomes (PROs): COPD assessment test (CAT) score, St. George's Respiratory Questionnaire for COPD patients (SGRQ-C) score, and six minute walk distance (6MWD). RESULTS: In the eligible 2,180 COPD patients, lower predicted values of FEV1 and forced vital capacity (FVC) were found in GLI-2012 compared to Choi's and KNHANES-VI equations. GLI-2012 equation resulted in a lower proportion of patients being classified as FEV1 < 80% or FVC < 80% compared to the other equations. However, the Z-scores of FEV1 and FVC were similar between the KNHANES-VI and GLI-2012 equations. Three reference equations exhibited significant associations between FEV1 (%) and patient-reported outcomes (CAT score, SGRQ-C score, and 6MWD). CONCLUSION: GLI-2012 reference equation may not accurately reflect FEV1 (%) in the Korean population, but the Z-score using GLI-2012 equation can be a viable option for assessing FEV1 and airflow limitation in COPD patients. Similar to the other two equations, the GLI-2012 equation demonstrated significant associations with PROs.

Characteristics of subclinical tuberculosis compared to active symptomatic tuberculosis using nationwide registry cohort in Korea: prospective cohort study.

Objective: The clinical manifestations of tuberculosis (TB) range from asymptomatic to disseminated depending on the microbiological and immunological status, making the diagnosis challenging. To improve our understanding of the disease progression mechanism, we aimed to identify the characteristics of subclinical TB and important predictors of symptom development. Methods: From July 2018 to June 2019, we systemically collected data from the National Surveillance System of South Korea on patients with pulmonary TB, and compared the characteristics of subclinical and active symptomatic TB patients. Results: A total of 4,636 patients with pulmonary TB were included, and the prevalence of subclinical TB was 37.1% (1,720/4,636). In subclinical TB patients, the positivity rates of acid-fast bacilli (AFB) smear and culture were 16.2 and 50.2%, respectively. Subclinical TB patients were younger (55.6 ± 19.2 vs. 60.7 ± 19.5, P < 0.001), had a higher body mass index (21.7 ± 3.1 vs. 21.0 ± 3.5, P < 0.001), less under Medicaid support, and had lower rates of chronic lung disease, AFB smear and culture positivity, and bilateral disease. Regarding the characteristic differences of individual TB-related symptoms, age was positively associated with dyspnoea and general weakness but negatively associated with chest pain, haemoptysis, and weight loss. Male patients were more prone to weight loss. Chronic lung disease was related to symptoms including cough/phlegm, dyspnoea, and haemoptysis, while autoimmune diseases were associated with fever and weight loss. Conclusions: The development of TB-related symptoms was associated with microbiological burden and clinical characteristics including underlying comorbidities, which should be evaluated carefully.

Effects of underweight and overweight on mortality in patients with pulmonary tuberculosis.

Background: Poor nutrition increases disease severity and mortality in patients with tuberculosis (TB). There are gaps in our understanding of the effects of being underweight or overweight on TB in relation to sex. Methods: We generated a nationwide TB registry database and assessed the effects of body mass index (BMI) on mortality in patients with pulmonary TB. The cause of death was further classified as TB-related or non-TB-related deaths. First, logistic regression analysis was performed to assess the association between BMI (a continuous variable) and mortality, and subgroup analyses of the multivariable logistic regression model were performed separately in male and female patients. Second, we categorized BMI into three groups: underweight, normal weight, and overweight, and assessed the impact of being underweight or overweight on mortality with reference to normal weight. Results: Among 9,721 patients with pulmonary TB, the mean BMI was 21.3 ± 3.4; 1,927 (19.8%) were underweight, and 2,829 (29.1%) were overweight. In multivariable logistic regression analysis, mortality was significantly increased with the decrement of BMI (adjusted odds ratio [aOR] = 0.893, 95% confidence interval [CI] = 0.875-0.911). In subgroup analyses, underweight patients had significantly higher odds of mortality, especially TB-related deaths (aOR = 2.057, 95% CI = 1.546-2.735). The association with mortality and male patients was higher (aOR = 2.078, 95% CI = 1.717-2.514), compared with female patients (aOR = 1.724, 95% CI = 1.332-2.231). Being overweight had a significant protective effect against TB-related death only in females (aOR = 0.500, 95% CI = 0.268-0.934), whereas its effect on non-TB-related death was observed only in males (aOR = 0.739, 95% CI = 0.587-0.930). Conclusion: Being underweight was linked to high mortality, whereas being overweight had beneficial effects in patients with pulmonary TB.

Clinical significance of normalized airflow obstruction in patients with chronic obstructive pulmonary disease.

BACKGROUND: There is ongoing debate regarding the diagnostic criteria for chronic obstructive pulmonary disease (COPD); recent studies have focused on the early COPD detection and management. Here, we compared clinical features and prognosis in patients with FEV1/FVC<0.70 at baseline, according to normalized airflow obstruction status during follow-up. METHODS: We used the Korea COPD Subgroup Study (KOCOSS) cohort database, a prospective nationwide observational COPD study. Normalized obstruction (NO) was defined as FEV1/FVC ≥0.7 in the 2-year follow-up period, whereas fixed obstruction (FO) was defined as FEV1/FVC <0.7. Demographic and clinical data, 1-year exacerbation risk and difference in FEV1 decline over 2 years were compared between NO and FO groups. RESULTS: Among the 670 COPD patients with post-bronchodilator FEV1/FVC <0.7 in this study, 95 (14.2%) displayed NO. Compared with the FO group, the NO group had higher FEV1, and DLCO, body mass index, as well as lower Saint George Respiratory Questionnaire, Beck Depression Index, and Beck Anxiety Index. Blood eosinophil count, IgE level, and FeNO did not significantly differ between two groups. There was no significant difference in exacerbation frequency between the two groups, but the NO group had a significant increase in FEV1 compared with the FO group during follow-up. CONCLUSION: Transient airflow obstruction in the NO group may represent a clinical manifestation of early COPD; close monitoring is needed for such patients.

Comparison of pneumonia incidence between long-acting muscarinic antagonist and inhaled corticosteroid plus long-acting beta agonist in patients with COPD.

Few studies have directly compared the incidence of pneumonia in patients on common chronic obstructive pulmonary disease (COPD) treatments such as long-acting muscarinic antagonists (LAMA) with those on inhaled corticosteroids and long-acting ß2-agonist (ICS/LABA). Moreover, risk factors for pneumonia in COPD are still unclear. We aimed to compare the incidence of pneumonia in COPD patients on LAMA and those on ICS/LABA and explored the risk factors associated with pneumonia. This nationwide cohort study used Korean National Health Insurance claim data from January 2002 to April 2016. Patients who received COPD medication, either LAMA or ICS/LABA, with the COPD diagnostic code, were selected. We enrolled patients with good compliance (medication possession ratio ≥ 80%). The primary outcome was pneumonia in COPD patients initiating LAMA or ICS/LABA. We investigated the risk factors associated with pneumonia, including the sub-types of ICS treatments. After propensity score matching, the incidence rate per 1000 person-years of pneumonia was 93.96 for LAMA (n = 1003) and 136.42 for ICS/LABA (n = 1003) patients (p < 0.001). The adjusted hazard ratio (HR) for pneumonia in patients on fluticasone/LABA was 1.496 (95% confidence interval [CI] 1.204-1.859) compared with LAMA (p < 0.001). In multivariable analysis, a history of pneumonia was a risk factor associated with pneumonia (HR 2.123; 95% CI 1.580-2.852; p < 0.001). The incidence of pneumonia was higher in COPD patients on ICS/LABA compared with those on LAMA. It is recommended that ICS use be avoided in COPD patients with high pneumonia risk.

Definitions of Chronic Obstructive Pulmonary Disease and Chronic Obstructive Pulmonary Disease Exacerbation: A Modified Delphi Survey.

BACKGROUND: The Global Initiative for Chronic Obstructive Lung Disease (GOLD) update 2023 proposed new definitions of chronic obstructive pulmonary disease (COPD) and COPD exacerbation. However, an agreement on the definitions has not been made, either internationally or domestically. This study aimed to reach an agreement between experts on the new definitions of COPD and COPD exacerbation in South Korea. METHODS: A modified Delphi method was used to make an agreement on the definitions of COPD and COPD exacerbation proposed by the GOLD update 2023. We performed two rounds of the survey including 15 Korean experts on COPD, asthma, and tuberculosis. RESULTS: More than two-thirds of the experts agreed on 12 of the 13 statements related to the definitions of COPD and COPD exacerbation in the two rounds of the survey. The experts agreed on the definitions of COPD and COPD exacerbation that should be revised in line with the definitions proposed by the GOLD update 2023. However, the experts showed an uncertain opinion on the statement that the definition of COPD includes patients with persistent airflow obstruction due to bronchiectasis. CONCLUSION: Based on this Delphi survey, experts' agreement was made on the definitions of COPD and COPD exacerbation proposed by the GOLD update 2023.

Recent Prevalence of and Factors Associated With Chronic Obstructive Pulmonary Disease in a Rapidly Aging Society: Korea National Health and Nutrition Examination Survey 2015-2019.

BACKGROUND: The prevalence of chronic obstructive pulmonary disease (COPD) increases with age, and aging is an important risk factor for COPD development. In the era of global aging, demographic information about the prevalence of and factors associated with COPD are important to establish COPD care plans. However, limited information is available in rapidly aging societies, including Korea. METHODS: We conducted a cross-sectional observational study using Korea National Health and Nutrition Examination Survey data from 2015-2019. We included 15,613 participants and analyzed trends of and factors associated with COPD. RESULTS: During the study period, the overall prevalence of COPD was 12.9%. Over five years, the yearly prevalence of COPD was fairly constant, ranging from 11.5% to 13.6%. Among individuals aged ≥ 70 years, nearly one-third met COPD diagnostic criteria. In the multivariable analysis, age 70 years or older was the most strong factor associated with COPD (adjusted odds ratio [aOR], 17.86; 95% confidence interval [CI], 14.16-22.52; compared with age 40-49), followed by asthma (aOR, 3.39; 95% CI, 2.44-4.71), male sex (aOR, 2.64; 95% CI, 2.18-3.19), and current smokers (aOR, 2.60; 95% CI, 2.08-3.25). Additionally, ex-smokers, low income, decreased forced expiratory volume in 1 second %pred, and a history of pulmonary tuberculosis were associated with COPD. On the other hand, body mass index (BMI) ≥ 25 kg/m² (aOR, 0.62; 95% CI, 0.54-0.71; compared with BMI 18.5-24.9 kg/m²) had an inverse association with COPD. CONCLUSION: Recent trends in the prevalence of COPD in South Korea are relatively stable. Approximately one-third of participants aged 70 years and older had COPD. Aging was the most important factor associated with COPD.

Risk Factors of Rapid FEV1 Decline in a Real-World Chronic Obstructive Pulmonary Disease Cohort.

BACKGROUND: Rapid forced expiratory volume in 1 s (FEV1) decliners have been considered a unique subgroup of patients with chronic obstructive pulmonary disease (COPD). Rapid FEV1 decline manifests early and is associated with poor prognosis. This necessitates the pre-emptive identification of risk factors for rapid FEV1 decline. OBJECTIVES: We aimed to determine the risk factors and clinical outcomes in patients with COPD. METHODS: This longitudinal, observational study was based on the Korea COPD Subgroup Study cohort (NCT02800499) from January 2012 to December 2019 across 54 medical centers in South Korea. Eligible patients were followed up for 3 years with serial spirometric tests. We calculated the annualized percentage change in FEV1 from baseline. Rapid decliners were defined as the quartile of patients with the highest annualized percentage FEV1 decline. RESULTS: Of the 518 patients, 130 were rapid decliners who lost 6.2%/year and 100 mL/year of FEV1. The multivariable logistic regression identified male sex, current smoking, blood eosinophil count <150/µL, and high forced vital capacity as the independent risk factors for rapid FEV1 decline. Among rapid decliners, the lung function deteriorated more rapidly in current smokers and patients with severe dyspnea, while triple combination therapy attenuated lung function decline in comparison with mono-bronchodilator therapy. Rapid decliners had a higher rate of severe exacerbation than nonrapid decliners (0.2/year vs. 0.1/year, p value = 0.032). CONCLUSIONS: We identified the independent risk factors for rapid FEV1 decline. This information may assist physicians in the early detection and pertinent management of rapid decline among patients with COPD.

Incidence and outcomes of adverse drug reactions to first-line anti-tuberculosis drugs and their effects on the quality of life: A multicenter prospective cohort study.

BACKGROUND: In tuberculosis (TB) treatment, adverse drug reactions (ADRs) can interrupt treatment and decrease the quality of life (QoL). We aimed to prospectively investigate the incidence of ADRs to first-line anti-TB drugs and related outcomes and QoL. METHODS: Adult patients with TB who had been treated with first-line anti-TB drugs in five Korean hospitals were enrolled. ADR questionnaire surveys and blood tests were performed four times serially, and QoL was assessed on the fourth TB treatment week (±2 weeks). RESULTS: Of 410 enrolled patients with TB (males, 62%; mean age, 52.1 ± 18.1 years [those aged ≥65 years, 26.6%]), 67.8% experienced any ADRs (≥ grade 2) to TB drugs. The most common ADR was fatigue (53.2%), followed by itching (42.7%) and anorexia (41.7%). Older adult patients experienced relatively more ADRs, including anorexia, dyspepsia, rash, dizziness, anemia, abnormal hepatic/renal function tests, and increased uric acid levels (p < 0.05). Treatment regimens changed for 9.5% of patients owing to ADRs to anti-TB drugs. Patients with any ADRs and older adult patients had significantly lower QoL than their counterparts (p < 0.05). Old age (odds ratio [OR], 1.02) and being male (OR 2.65) were independently associated with ADRs, whereas active smoking (OR 4.73) and a relatively long treatment phase (OR 5.13) were independently associated with hepatotoxicity. CONCLUSION: ADRs to first-line anti-TB drugs were common and related to relatively low QoL, especially among older adults. Although 9.5% of patients had ADR-related regimen changes, most patients with ADRs completed treatments successfully.

Clinical characteristics of patients with COVID-19 vaccine-related pneumonitis: a case series and literature review.

BACKGROUND/AIMS: Pulmonary toxicities of coronavirus disease 2019 (COVID-19) vaccination are exceedingly rare. However, there are a few reported cases after mRNA vaccination, especially from Asian countries. The purpose of this study was to report the clinical characteristics of patients with COVID-19 vaccine-related pneumonitis (CV-P) and to review cases reported in the literature. METHODS: We performed a prospective, observational case series analysis. RESULTS: Eleven patients with a median age of 80 years were enrolled. Ten patients developed CV-P after BNT162b2-mRNA vaccination and one after ChAdOx1 nCoV-19 vaccination. We identified various patterns of CV-P, including transient infiltration, life-threatening acute respiratory distress syndrome, and aggravation of underlying interstitial lung disease. Most patients showed favorable outcomes with good responses to corticosteroid therapy. CONCLUSION: Identifying the mechanism of CV-P requires further investigation; however, radiological and laboratory findings in our case series support inflammatory dysregulation in the lung parenchyma after vaccination. Clinicians should consider CV-P in patients with atypical lung infiltration, no specific etiologies, and recent COVID-19 vaccination.

Associations Between Asthma Diagnosis/Asthma Exacerbation and Previous Proton-Pump Inhibitor use: A Nested Case-Control Study Using a National Health Screening Cohort.

Background: Proton-pump inhibitors (PPIs) block acid secretion from gastric parietal cells; however, recent studies have reported that PPIs have antioxidant and anti-inflammatory properties in various cells. Newer PPIs are stronger inhibitors of acid secretion; however, the anti-inflammatory effects of these drugs have not been assessed. We evaluated anti-inflammatory effect of PPIs on the development of asthma/asthma exacerbation (AE) in a national health screening cohort. Methods: This case-control study comprised 64,809 participants with asthma who were 1:1 matched with controls from the Korean National Health Insurance Service-Health Screening Cohort. Conditional logistic regression analysis was used to evaluate the effect of previous PPI use on an asthma diagnosis in all participants. Unconditional logistic regression was used to assess the effect of PPI use on AE in participants with asthma. These relationships were estimated in a subgroup analysis according to PPI generation. Results: Overall, PPI use increased the risk of asthma diagnosis [adjusted odds ratio (aOR) = 1.29, 95% confidence interval (CI) = 1.23-1.35, p < 0.001]. Use of the first-generation PPIs was associated with asthma (aOR = 1.34, 95% CI = 1.18-1.52, p < 0.001), while use of second-generation PPIs was not (aOR = 0.97, 95% CI = 0.82-1.15, p = 0.748). In contrast, overall PPI use decreased the risk of AE in participants with asthma (aOR = 0.79, 95% CI = 0.75-0.84, p < 0.001), although this effect was observed only for second-generation PPIs (aOR = 0.76, 95% CI = 0.65-0.89, p = 0.001). Conclusion: PPI use increased the risk for subsequent asthma diagnosis. However, this effect was confined to first-generation PPIs. Second-generation PPIs decreased the risk of AE.

Ambulatory oxygen therapy with documented self-monitoring of oxygen use improves health status among patients with chronic obstructive pulmonary disease.

Background: Home oxygen therapy is well known to improve survival among patients with severe chronic obstructive pulmonary disease (COPD). In Korea, home oxygen therapy has been reimbursed by national health care insurance since 2006. However, an adequate management strategy for home oxygen therapy is not yet established in Korea. This pilot study aimed to develop a new management strategy for home oxygen therapy. Methods: We developed a new home oxygen service strategy for COPD patients. The new strategy consists of patient education materials, "oxygen notes" for oxygen use self-monitoring, and provision of ambulatory oxygen. Using a structured questionnaire, we explored the usefulness of the new strategy and health status changes among patients before and after the study period. Results: Among 29 participants, the mean age was 69.6 years, and 62.1% were male. At the end of the study, the proportion of patients with severe dyspnea [modified Medical Research Council (mMRC) grade 4] decreased from 62.1% to 41.4%. The mean COPD assessment test score improved from 30.3 to 24.7, and 68.9% of patients scored above the minimum clinically important difference. The mean time and amount of ambulatory oxygen administration changed significantly by the end of the study. More than three-quarters of patients were satisfied with the educational material and oxygen note. Conclusions: We showed that the new home oxygen service strategy improved the health status of COPD patients. Larger-scale and longer-term research to validate these results is warranted.

The Relationship Between Comorbidities and Microbiologic Findings in Patients with Acute Exacerbation of Chronic Obstructive Pulmonary Disease.

Purpose: Data regarding the relationship between microbiologic features and comorbidities in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) are limited. The aim of this study was to correlate microbiologic findings with comorbidities in patients with moderate to severe AECOPD. Patients and Methods: This multicenter observational study included patients with AECOPD seen at 28 hospitals in South Korea between January 2015 and December 2018, and the data were retrospectively collected. Pathogens were examined in patients with either pulmonary or extrapulmonary comorbidities, and compared to those of patients without comorbidities. The relationship between pathogen type and the number of comorbidities was also evaluated. Results: Bacterial infections (178 [37.2%] vs 203 [28.7%], p = 0.002) and co-infections with bacteria and viruses (65 [13.6%] vs 57 [8.1%], p = 0.002) were more prevalent in patients with pulmonary comorbidities. Bacterial pathogens (280 [34.7%] vs 101 [26.7%], p=0.006) were detected at a higher rate in patients with extrapulmonary comorbidities. Previous pulmonary tuberculosis (PTB), bronchiectasis, and diabetes mellitus were risk factors for bacterial infection, and congestive heart failure was a risk factor for bacterial and viral co-infection. As the number of comorbidities increased, the risk of bacterial infection increased considerably. Pseudomonas aeruginosa was more frequently identified in patients with previous PTB (57 [15.3%] vs 59 [7.4%], p < 0.001) and bronchiectasis (33 [19.6%] vs 83 [8.3%], p < 0.001). Conclusion: AECOPD patients with comorbidities were more likely to experience infection-related exacerbations compared to those without comorbidities. As the overall number of comorbidities increased, the risk of bacterial infection increased significantly.

The Influence of Prior Statin Use on the Prevalence and Exacerbation of Chronic Obstructive Pulmonary Disease in an Adult Population.

Background: Statins have anti-inflammatory and antioxidant properties, and previous studies have reported the positive effects of statins on chronic obstructive pulmonary disease (COPD) outcomes. However, the effects of statins on the development and acute exacerbations of COPD remain unclear. Therefore, this study aimed to assess the relation between statin use and COPD occurrence in all participants and the link between statin use and COPD acute exacerbations in participants with COPD. Methods: This case-control study comprised 26,875 COPD participants and 107,500 control participants who were 1:4 matched from the Korean National Health Insurance Service-Health Screening Cohort. Conditional logistic regression was used to evaluate the probability of COPD occurrence associated with previous statin use. In addition, unconditional logistic regression was employed to assess the risk of exacerbations related to statin use among COPD participants. These relations were estimated in subgroup analysis according to statin type (lipophilic vs. hydrophilic). Results: The association between previous statin use and the occurrence of COPD did not reach statistical significance in the overall population (adjusted odds ratio [aOR] = 0.96, 95% confidence interval [CI] = 0.93-1.00, P = 0.059). However, statin use decreased the probability of exacerbations in participants with COPD (aOR = 0.79, 95% CI = 0.74-0.85, P < 0.001). Lipophilic statins decreased the probability of exacerbations, whereas hydrophilic statins were not associated with a decreased likelihood of exacerbations (aOR = 0.78, 95% CI = 0.72-0.84, P < 0.001 for lipophilic statins; aOR = 0.89, 95% CI = 0.78-1.02, P = 0.102 for hydrophilic statins). Discussion: Statin use was not associated with the occurrence of COPD in the adult population. However, statin use was associated with a reduced probability of exacerbations in participants with COPD, with a greater risk reduction with lipophilic statin use.