Clinical Characteristics of Non-Smoking Chronic Obstructive Pulmonary Disease Patients: Findings from the KOCOSS Cohort.

Chronic obstructive pulmonary disease (COPD) has been regarded as a disease of smokers, but the prevalence of non-smoking COPD patients have been reported to be considerable. We investigated differences in clinical characteristics between smoking and non-smoking COPD patients. We used data from the Korea COPD Subgroup Study (KOCOSS) database, which is a multicenter cohort that recruits patients from 54 medical centres in Korea. Comprehensive comparisons of smoking and non-smoking COPD patients were performed based on general characteristics, exacerbations, symptom scores, radiological findings, and lung-function tests. Of the 2477 patients included in the study, 8.1% were non-smokers and 91.9% were smokers. Non-smoking COPD patients were more likely to be female and to have a higher body mass index and lower level of education. Non-smoking COPD patients had more comorbidities, including hypertension, osteoporosis, and gastroesophageal reflux disease, and experienced more respiratory and allergic diseases. No significant differences in exacerbation rates, symptom scores, or exercise capacity scores were observed between the two groups. Smoking COPD patients had more emphysematous lung according to the radiological findings, and non-smoking patients had more tuberculosis-destroyed lung and bronchiectasis. Lung-function testing revealed no significant difference in the forced expiratory capacity in 1 sec between the two groups, but smokers had more rapid lung-function decline in the 5 years of follow-up data. We found differences in general characteristics and radiological findings between smoking and non-smoking COPD patients. No significant differences in exacerbation or symptom scores were observed, but decline in lung function was less steep in non-smoking patients.Supplemental data for this article is available online at https://doi.org/10.1080/15412555.2022.2053088 .

Effectiveness of Mesenchymal Stem Cell Therapy for COVID-19-Induced ARDS Patients: A Case Report.

Purpose: This study assessed the safety, feasibility, and tolerability of mesenchymal stem cells for patients diagnosed with COVID (Coronavirus disease 2019-induced ARDS (acute respiratory distress syndrome)). Materials and Methods: Critically ill adult COVID-19 patients who were admitted to Wonju Severance Christian Hospital were enrolled in this study. One patient received human bone marrow-derived mesenchymal stem cell (hBMSC) transplantation and received a total dose of 9 × 107 allogeneic hBMSCs via intravenous infusion. The main outcome of this study was to assess the safety, adverse events, and efficacy following transplantation of hBMSCs in COVID-19- induced ARDS patients. Efficacy was assessed radiologically based on pneumonia improvement, changes in PaO2/FiO2, and O2 saturation. Results: A 73-year-old man visited Wonju Severance Christian Hospital presenting with fever and fatigue. A throat swab was performed for real-time polymerase chain reaction to confirm COVID-19, and the result was positive. The patient developed ARDS on Day 5. MSC transplantation was performed on that day and administered on Day 29. Early adverse events, including allergic reactions, were not observed following MSC transplantation. Subsequently, clinical symptoms, signs, and laboratory findings, including PaO2/FiO2 and O2 saturation, improved. Conclusion: The results of this case report suggest that intravenous injection of MSC derived from the bone marrow is safe and acceptable and can lead to favorable outcomes for critically ill COVID-19 patients.

Developmental endothelial locus-1 as a potential biomarker for the incidence of acute exacerbation in patients with chronic obstructive pulmonary disease.

BACKGROUND: Despite the high disease burden of chronic obstructive pulmonary disease (COPD) and risk of acute COPD exacerbation, few COPD biomarkers are available. As developmental endothelial locus-1 (DEL-1) has been proposed to possess beneficial effects, including anti-inflammatory effects, we hypothesized that DEL-1 could be a blood biomarker for COPD. OBJECTIVE: To elucidate the role of plasma DEL-1 as a biomarker of COPD in terms of pathogenesis and for predicting acute exacerbation. METHODS: Cigarette smoke extract (CSE) or saline was intratracheally administered to wild-type (WT) and DEL-1 knockout (KO) C57BL/6 mice. Subsequently, lung sections were obtained to quantify the degree of emphysema using the mean linear intercept (MLI). Additionally, plasma DEL-1 levels were compared between COPD and non-COPD participants recruited in ongoing prospective cohorts. Using negative binomial regression analysis, the association between the plasma DEL-1 level and subsequent acute exacerbation risk was evaluated in patients with COPD. RESULTS: In the in vivo study, DEL-1 KO induced emphysema (KO saline vs. WT saline; P = 0.003) and augmented CSE-induced emphysema (KO CSE vs. WT CSE; P < 0.001) in 29 mice. Among 537 participants, patients with COPD presented plasma log (DEL-1) levels lower than non-COPD participants (P = 0.04), especially non-COPD never smokers (P = 0.019). During 1.2 ± 0.3 years, patients with COPD in the lowest quartile of Log(DEL-1) demonstrated an increased risk of subsequent acute exacerbation, compared with those in the highest quartile of Log(DEL-1) (adjusted incidence rate ratio, 3.64; 95% confidence interval, 1.03-12.9). CONCLUSION: Low DEL-1 levels are associated with COPD development and increased risk of subsequent COPD acute exacerbation. DEL-1 can be a useful biomarker in patients with COPD.

Prevalence of depression and its associated factors in bronchiectasis: findings from KMBARC registry.

BACKGROUND: With the emergence of bronchiectasis as a common respiratory disease, epidemiological data have accumulated. However, the prevalence and impact of psychological comorbidities were not sufficiently evaluated. The present study examined the prevalence of depression and its associated factors in patients with bronchiectasis. METHODS: This study involved a multicenter cohort of bronchiectasis patients recruited from 33 pulmonary specialist hospitals. The baseline characteristics and bronchiectasis-related factors at enrollment were analyzed. Depressive symptoms were assessed using the Patient Health Questionnaire (PHQ-9). RESULTS: Of the 810 patients enrolled in the study, 168 (20.7%) patients had relevant depression (PHQ-9 score ≥ 10), and only 20 (11.9%) patients had a diagnosis of depression. Significant differences were noted in the depressive symptoms with disease severity, which was assessed using the Bronchiectasis Severity Index and E-FACED (all p < 0.001). Depressive symptoms inversely correlated with quality-of-life (r = - 0.704, p < 0.001) and positively correlated with fatigue severity score (r = 0.712, p < 0.001). Multivariate analysis showed that depression was significantly associated with the modified Medical Research Council dyspnea scale ≥ 2 (OR 2.960, 95% CI 1.907-4.588, p = < 0.001) and high number of exacerbations (≥ 3) in the previous year (OR 1.596, 95% CI 1.012-2.482, p = 0.041). CONCLUSIONS: Depression is common, but its association with bronchiectasis was underrecognized. It negatively affected quality-of-life and presented with fatigue symptoms. Among the bronchiectasis-related factors, dyspnea and exacerbation were closely associated with depression. Therefore, active screening for depression is necessary to optimize the treatment of bronchiectasis. TRIAL REGISTRATION: The study was registered at Clinical Research Information Service (CRiS), Republic of Korea (KCT0003088). The date of registration was June 19th, 2018.

Safety and Utility of Rush Immunotherapy with Aqueous Allergen Extracts for Treatment of Respiratory Allergies.

BACKGROUND: Generally, allergen immunotherapy must be administered for three to five years. Meanwhile, rush immunotherapy (RIT) shortens the required duration for the build-up phase, thereby improving the therapy's convenience compared with conventional immunotherapy (CIT). However, RIT is often performed with modified allergens. Therefore, this study aimed to investigate the safety and utility of RIT with aqueous allergens. METHODS: Medical records of 98 patients sensitized with at least one inhalant allergen who had received subcutaneous immunotherapy for allergic rhinitis with or without asthma were retrospectively reviewed. All patients were classified into three groups: depot-RIT (n = 25), receiving RIT with depot allergen; aqueous-RIT (n = 48), receiving RIT with aqueous allergen; and aqueous-CIT (n = 25), receiving CIT with aqueous allergen. Patients who had received immunotherapy targeting only house dust mites were excluded. RESULTS: The proportions of patients presenting with a systemic reaction to depot-RIT, aqueous-RIT, or aqueous-CIT were 80.0%, 85.4%, and 48.0%, respectively (P = 0.002). The proportions of patients experiencing severe systemic reaction were 4.0%, 16.7%, and 8.0% in depot-RIT, aqueous-RIT and aqueous-CIT, respectively (P = 0.223). The proportions of depot-RIT and aqueous-RIT patients presenting with systemic reaction or severe systemic reaction did not differ significantly (P = 0.553 and P = 0.118, respectively). Significantly fewer depot-RIT (1.0 ± 0.2) and aqueous-RIT patients (2.0 ± 1.3) required outpatient clinical visits during the build-up phase, compared to those administered aqueous-CIT (13.6 ± 1.9; P < 0.001). Moreover, the build-up phase decreased to 17.4 ± 1.8 days in depot-RIT and 23.7 ± 10.9 days in aqueous-RIT, compared to 92.0 ± 12.5 days in aqueous-CIT (P < 0.001). CONCLUSION: RIT with aqueous allergen reduced the build-up phase duration and frequency of hospital visits, with acceptable safety levels. RIT with aqueous allergen may, therefore, be suitable for broad application to patients with respiratory allergies.

Pleural fluid ADA activity in tuberculous pleurisy can be low in elderly, critically ill patients with multi-organ failure.

BACKGROUND: Adenosine deaminase (ADA) activity is typically elevated in patients with tuberculous pleural effusion (TPE), but low ADA has occasionally been reported in patients with TPE. The characteristics of these patients are not well-known, and erroneous exclusion of the possibility of TPE can result in a delayed diagnosis. This study investigated the characteristics of patients with TPE who had low ADA activity. METHODS: We retrospectively reviewed patients with microbiologically or pathologically confirmed TPE between 2012 to 2018 in a tertiary hospital in South Korea. Patients were categorised into two groups: high ADA (≥40 IU/L) and low ADA (< 40 IU/L). Clinical characteristics and Sequential Organ Failure Assessment (SOFA) scores were compared between groups. RESULTS: A total of 192 patients with TPE were included; 36 (18.8%) had ADA < 40 IU/L with a mean ADA activity level of 20.9 (±9.2) IU/L. Patients with low ADA were older (75.3 vs. 62.0 years, p < 0.001) and had a lower mean lymphocyte percentage (47.6% vs. 69.9%, p < 0.001) than patients with high ADA. Patients in the low ADA group had a significantly higher mean SOFA score (2.31 vs. 0.68, p < 0.001), and patients with organ dysfunction were significantly more common in the low ADA group (p < 0.001). Patients with 2 or ≥ 3 organ dysfunctions constituted 19.4 and 13.9% of the patients in the low ADA group, whereas they constituted 7.1 and 1.3% of the patients in the high ADA group (p < 0.001). Multivariate logistic regression analyses showed that older age (odds ratio = 1.030, 95% confidence interval 1.002-1.060, p = 0.038) and a higher SOFA score (odds ratio = 1.598, 95% confidence interval 1.239-2.060, p < 0.001) were significantly associated with low ADA activity in patients with TPE. CONCLUSIONS: ADA activity can be low in patients with TPE who are elderly, critically ill, and exhibit multiorgan failure. Low ADA activity cannot completely exclude the diagnosis of TPE, and physicians should exercise caution when interpreting pleural fluid exams.

Validation of Previous Spirometric Reference Equations and New Equations.

BACKGROUND: Pulmonary functions are interpreted using predicted values from reference equations that vary with ethnicity, gender, age, height, and weight. The universally used Choi's reference equations are not validated for Korean populations, and the purpose of this study was to validate them and develop new reference equations. METHODS: Subjects with normal spirometry and chest radiographs, no co-morbidities, and non-smokers, from the Korean National Health and National Examination Survey (KNHANES)-VI were enrolled (n = 117). Intraclass correlation coefficient (ICC) was assessed for reliability of reference equations. New reference equations were developed using linear regression analysis. Differences between observed and predicted values were assessed to compare the reference equations from Choi's, Global Lung Function Initiative 2012, KNHANES-IV, and newly developed equations. RESULTS: The ICC of Choi's reference equations was 0.854 (P < 0.001). The new reference equations for men were: forced vital capacity (FVC) (L) = - 4.38775 - 0.01184 × age + 0.05547 × height, forced expiratory volume - 1 second (FEV1) (L) = - 2.40147 - 0.02134 × age + 0.04103 × height; and for women: FVC (L) = - 3.09063 + 0.003904 × age + 0.038694 × height; FEV1 (L) = - 1.32933 - 0.00872 × age + 0.02762 × height. The differences between the predicted and observed means were largest in Choi's equations, but lowest in the new equations with highest goodness of fit. CONCLUSION: Because Choi's reference equations presented larger differences from the observed values, despite reliability, and the new reference equations showed better goodness of fit, we suggest the latter for Korean populations.

Early readmission and mortality in acute exacerbation of chronic obstructive pulmonary disease with community-acquired pneumonia.

Acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are important causes of hospital admission and mortality. Pneumonia is a major contributor to hospitalization for AECOPD and has a close relationship with poor outcomes. We performed a prospective cohort study to evaluate the prognosis of AECOPD patients with or without community-acquired pneumonia (CAP) who hospitalized from January 2012 to December 2015. We investigated mortality and readmission rates within 6 months after the first admission between two groups and analyzed the difference of survival rate according to readmission duration (≤30 vs. >30 days) or intensive care unit (ICU) treatment. Total 308 AECOPD patients (134 with CAP and 174 without CAP) were enrolled. The mean age was 72.3 ± 9.5 years old, and 235 patients (76.3%) were male. The 180-day mortality was higher in AECOPD with CAP than without CAP (24.6% vs. 13.2%; hazard ratio (HR): 1.982; 95% CI: 1.164-3.375; p = 0.012). However, readmission rate showed no significant difference between two groups (51.5% vs. 46.6%; HR: 1.172; 95% CI: 0.850-1.616; p = 0.333). It showed a significantly lower survival rate in AECOPD with CAP rather than without CAP when were readmitted within 30 days (HR: 1.738; 95% CI:1.063-3.017; p = 0.031). According to ICU treatment, survival rate was not significantly different between two groups. Multivariate analysis revealed the readmission within 30 days ( p < 0.001), serum hemoglobin concentration ( p = 0.010), and albumin level ( p = 0.049) were significantly associated with 180-day mortality of AECOPD with CAP. AECOPD with CAP showed lower survival rate than AECOPD without CAP during 6 months. Early readmission within 30 days was significantly associated with an increased risk of mortality.

Asthma and severity of the 2009 novel H1N1 influenza: a case-control study.

OBJECTIVE: Previous studies reported that the most common chronic condition found among hospitalized patients due to the novel 2009 H1N1 influenza was asthma. However, these studies did not include a concurrent control group. Thus, we investigated the association of asthma status and severity of H1N1 influenza in adults. METHODS: The study was designed as a multi-site case-control study. Cases were patients who had positive PCR for H1N1 influenza and were admitted to the ICU or general ward with a diagnosis of H1N1 influenza from 1 January 2009 to 31 December 2009. Controls were patients who had positive PCR for H1N1 influenza, but were not admitted to hospitals. RESULTS: There were 91 H1N1 cases admitted to either ICU (n = 41) or general hospital ward (n = 50), and 56 controls who met the matching criteria were available. Of the 91 cases, the mean age was 47.3 years, 59% were female, and 38% had comorbid conditions. Of the 91 cases, 12 (13%) had asthma. Stratified analysis by comorbid conditions showed that among those without any comorbid conditions, 8 of 56 cases (14%) and 2 of 49 controls (4%) had asthma, (OR: 3.92, 95% CI: 0.79-19.42, p = 0.095) whereas, among the 39 subjects with one or more comorbid conditions, one of 7 controls (14%) had asthma and 4 of 35 (11%) cases had asthma (p = 0.83). CONCLUSIONS: Asthma may be associated with severity of H1N1 influenza among those without any non-asthma comorbid conditions. However, the limited sample size did not allow this study to fully establish statistical significance. We still recommend asthmatics as a priority group for influenza vaccination and treatment.

Clinical demographics and outcomes in mechanically ventilated patients in Korean intensive care units.

Knowledge of clinical demographics and outcomes of mechanically ventilated patients is important but there are few prospectively collected data in Korea. The objective of the present study was to describe the current status of mechanically ventilated patients in Korea as of 2010. We analyzed the data of Korean patients (275 patients in 12 Korean intensive care units [ICU]) participating in a multinational prospective cohort study on mechanical ventilation. The most common indication for mechanical ventilation was pneumonia (23%). Pressure-limited ventilation modes were preferred over volume-cycled ventilation modes. Non-invasive positive pressure ventilation was used in only seven (2%) patients as the initial ventilatory support. Median duration of mechanical ventilation was 7 days and ICU mortality was 36%. The multiple logistic regression model revealed that the Simplified Acute Physiology Score II (SAPS II) score at ICU admission (odds ratio [OR], 1.034; 95% confidence interval [CI], 1.001-1.036; P=0.033), peak pressure (OR, 1.054; 95% CI, 1.016-1.095; P=0.006), and the number of failed organs (OR, 2.132; 95% CI, 1.634-2.781; P<0.001) were independently associated with ICU mortality. This study provides a snapshot of current practice of mechanical ventilation in Korea.

Inhaled Corticosteroids May Not Affect the Clinical Outcomes of Pneumonia in Patients with Chronic Obstructive Pulmonary Disease.

BACKGROUND: Although inhaled corticosteroids (ICS) is reportedly associated with a higher risk of pneumonia in chronic obstructive pulmonary disease (COPD), the clinical implications of ICS have not been sufficiently verified to determine their effect on the prognosis of pneumonia. METHODS: The electronic health records of patients hospitalized for pneumonia with underlying COPD were retrospectively reviewed. Pneumonia was confirmed using chest radiography or computed tomography. The clinical outcomes of pneumonia in patients with COPD who received ICS and those who received long-acting bronchodilators other than ICS were compared. RESULTS: Among the 255 hospitalized patients, 89 met the inclusion criteria. The numbers of ICS and non-ICS users were 46 and 43, respectively. The CURB-65 (confusion, uremia, respiratory rate, blood pressure, age ≥65 years) scores at the initial presentation of pneumonia were comparable between the two groups. The proportions of patients with multilobar infiltration, pleural effusion, and complicated pneumonia in the radiological studies did not vary between the two groups. Additionally, the defervescence time, proportion of mechanical ventilation, intensive care unit admission, length of hospital stays, and mortality rate at 30 and 90 days were not significantly different between the two groups. ICS use and blood eosinophils count were not associated with all pneumonia outcomes and mortality in multivariate analyses. CONCLUSION: The clinical outcomes of pneumonia following ICS use in patients with COPD did not differ from those in patients treated without ICS. Thus, ICS may not contribute to the severity and outcomes of pneumonia in patients with COPD.

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.

Risk of Cardiovascular Events Associated with Chronic Obstructive Pulmonary Disease and/or Metabolic Syndrome: A Large-Scale Nationwide Population-Based Cohort Study.

Purpose: Chronic obstructive pulmonary disease (COPD) and metabolic syndrome (MetS) are among the most prevalent conditions that might predispose individuals to life-threatening events. We aimed to examine their associations with cardiovascular (CV) events and mortality using a large-scale population dataset from the National Health Information Database in Korea. Patients and Methods: This population-based cohort study enrolled adults aged ≥40 years who had undergone more than two health examinations between 2009 and 2011. They were divided into four groups based on the presence of COPD and MetS. Analysis of the outcomes and CV events or deaths was performed from 2014 to 2019. We compared CV event incidence and mortality rates using a multivariate Cox proportional hazards model and Kaplan-Meier curves. Results: Totally, 5,101,810 individuals were included, among whom 3,738,458 (73.3%) had neither COPD nor MetS, 1,193,014 (23.4%) had only MetS, 125,976 (2.5%) had only COPD, and 44,362 (0.9%) had both. The risk of CV events was significantly higher in individuals with both COPD and MetS than in those with either COPD or MetS alone (HRs: 2.4 vs 1.6 and 1.8, respectively; all P <0.001). Similarly, among those with both COPD and MetS, all-cause and CV mortality risks were also elevated (HRs, 2.9 and 3.0, respectively) compared to the risks in those with either COPD (HRs, 2.6 and 2.1, respectively) or MetS (HRs, 1.7 and 2.1, respectively; all P <0.001). Conclusion: The comorbidity of MetS in patients with COPD increases the incidence of CV events and all-cause and cardiovascular mortality rates.

Pulmonary Rehabilitation Is Associated With Decreased Exacerbation and Mortality in Patients With COPD: A Nationwide Korean Study.

BACKGROUND: Poor uptake to pulmonary rehabilitation (PR) is still challenging around the world. There have been few nationwide studies investigating whether PR impacts patient outcomes in COPD. We investigated the change of annual PR implementation rate, medical costs, and COPD outcomes including exacerbation rates and mortality between 2015 and 2019. RESEARCH QUESTION: Does PR implementation improve outcomes in patients with COPD in terms of direct cost, exacerbation, and mortality? STUDY DESIGN AND METHODS: Data of patients with COPD extracted from a large Korean Health Insurance Review and Assessment service database (2015-2019) were analyzed to determine the trends of annual PR implementation rate and direct medical costs of PR. Comparison of COPD exacerbation rates between pre-PR and post-PR, and the time to first exacerbation and mortality rate according to PR implementation, were also assessed. RESULTS: Among all patients with COPD in South Korea, only 1.43% received PR. However, the annual PR implementation rate gradually increased from 0.03% to 1.4% during 4 years, especially after health insurance coverage commencement. The direct medical cost was significantly higher in the PR group than the non-PR group, but the costs in these groups showed decreasing and increasing trends, respectively. Both the incidence rate and frequency of moderate-to-severe and severe exacerbations were lower during the post-PR period compared with the pre-PR period. The time to the first moderate-to-severe and severe exacerbations was longer in the PR group than the non-PR group. Finally, PR implementation was associated with a significant decrease in mortality. INTERPRETATION: We concluded that health insurance coverage increases PR implementation rates. Moreover, PR contributes toward improving outcomes including reducing exacerbation and mortality in patients with COPD. However, despite the well-established benefits of PR, its implementation rate remains suboptimal.

Critical care bed capacity in Asian countries and regions before and during the COVID-19 pandemic: an observational study.

Background: The coronavirus disease 2019 (COVID-19) pandemic highlighted the importance of critical care. The aim of the current study was to compare the number of adult critical care beds in relation to population size in Asian countries and regions before (2017) and during (2022) the pandemic. Methods: This observational study collected data closest to 2022 on critical care beds (intensive care units and intermediate care units) in 12 middle-income and 7 high-income economies (using the 2022-2023 World Bank classification), through a mix of methods including government sources, national critical care societies, personal contacts, and data extrapolation. Data were compared with a prior study from 2017 of the same countries and regions. Findings: The cumulative number of critical care beds per 100,000 population increased from 3.0 in 2017 to 9.4 in 2022 (p = 0.003). The median figure for middle-income economies increased from 2.6 (interquartile range [IQR] 1.7-7.8) to 6.6 (IQR 2.2-13.3), and that for high-income economies increased from 11.4 (IQR 7.3-22.8) to 13.9 (IQR 10.7-21.7). Only 3 countries did not see a rise in bed capacity. Where data were available in 2022, 10.9% of critical care beds were in single rooms (median 5.0% in middle-income and 20.3% in high-income economies), and 5.3% had negative pressure (median 0.7% in middle-income and 18.5% in high-income economies). Interpretation: Critical care bed capacity in the studied Asian countries and regions increased close to three-fold from 2017 to 2022. Much of this increase was attributed to middle-income economies, but substantial heterogeneity exists. Funding: None.

Association between mechanical power and intensive care unit mortality in Korean patients under pressure-controlled ventilation.

BACKGROUND: Mechanical power (MP) has been reported to be associated with clinical outcomes. Because the original MP equation is derived from paralyzed patients under volume-controlled ventilation, its application in practice could be limited in patients receiving pressure-controlled ventilation (PCV). Recently, a simplified equation for patients under PCV was developed. We investigated the association between MP and intensive care unit (ICU) mortality. METHODS: We conducted a retrospective analysis of Korean data from the Fourth International Study of Mechanical Ventilation. We extracted data of patients under PCV on day 1 and calculated MP using the following simplified equation: MPPCV = 0.098 ∙ respiratory rate ∙ tidal volume ∙ (ΔPinsp + positive end-expiratory pressure), where ΔPinsp is the change in airway pressure during inspiration. Patients were divided into survivors and non-survivors and then compared. Multivariable logistic regression was performed to determine association between MPPCV and ICU mortality. The interaction of MPPCV and use of neuromuscular blocking agent (NMBA) was also analyzed. RESULTS: A total of 125 patients was eligible for final analysis, of whom 38 died in the ICU. MPPCV was higher in non-survivors (17.6 vs. 26.3 J/min, P<0.001). In logistic regression analysis, only MPPCV was significantly associated with ICU mortality (odds ratio, 1.090; 95% confidence interval, 1.029-1.155; P=0.003). There was no significant effect of the interaction between MPPCV and use of NMBA on ICU mortality (P=0.579). CONCLUSIONS: MPPCV is associated with ICU mortality in patients mechanically ventilated with PCV mode, regardless of NMBA use.

Clinical characteristics and drug resistance profile of patients with endobronchial tuberculosis in South Korea: single-center experience.

BACKGROUND: Tuberculosis (TB) is a major infectious disease worldwide; there has been a significant increase in the number of elderly patients with TB, largely contributing to TB-related mortality. Although endobronchial tuberculosis (EBTB) is a unique form of pulmonary TB, available data on the clinical characteristics and drug susceptibility (DST) patterns of patients with EBTB are scarce. METHODS: We evaluated the clinical characteristics of patients with EBTB in South Korea and the culture-based DST patterns of EBTB. Further, the DST patterns were compared between elderly (≥65 years) and young (<65 years) patients. We retrospectively reviewed data of patients with EBTB who had the results of DST and were diagnosed between January 2013 and December 2019 at a tertiary referral hospital in South Korea. Phenotypic DST of 15 first-line and second-line anti-TB drugs was performed using Mycobacterium tuberculosis isolates prior to treatment. RESULTS: Of the 230 patients with EBTB, 69% were in elderly patients (≥65 years). Any-resistance occurred in 24 patients (10.4%), while multi-drug resistance (MDR) and extensive drug resistance (XDR) were observed in six patients (2.6%). Compared to that of the elderly treatment-naïve patients, previously treated elderly patients had a significantly higher proportion of resistance to rifampin (14.3% vs. 2.2%; P=0.031), ethambutol (9.5% vs. 0.7%; P=0.046), and pyrazinamide (9.5% vs. 0.7%; P=0.046). Further, MDR/XDR was observed more frequently in the previously treated elderly patients than that in the treatment-naïve elderly patients (14.3% vs. 1.4%; P=0.017). A relatively small number of drug-resistant cases (5.6%) were observed in young patients. CONCLUSIONS: Elderly EBTB patients with previous Anti-tuberculous medications had a significantly higher proportion of drug-resistant TB. These patients should be carefully assessed using DST analysis before treatment.

Inhaled Corticosteroids and the Risk of Nontuberculous Mycobacterial Pulmonary Disease in Chronic Obstructive Pulmonary Disease: Findings from a Nationwide Population-Based Study.

Studies have shown increased nontuberculous mycobacterial pulmonary disease (NTM) incidence with inhaled corticosteroid (ICS) use in patients with chronic respiratory diseases; however, this association in chronic obstructive pulmonary disease (COPD) remains insufficiently studied. Using a nationwide population-based database of the Korean National Health Insurance Service, newly diagnosed COPD patients (2005-2018) treated with inhaled bronchodilators were selected. An NTM case was defined by the presence of the first diagnostic code following inhaled bronchodilator use. Results indicated that ICS users did not have an increased risk of NTM disease compared to non-ICS users (hazard ratio (HR), 1.121; 95% confidence interval (CI), 0.950-1.323; p = 0.176). However, in a subgroup analysis, the highest quartile of the cumulative ICS dose was associated with the development of NTM (1.200, 0.950-1.323, p = 0.050). Medium (1.229, 1.008-1.499, p = 0.041) and high daily doses of ICS (1.637, 1.241-2.160, p < 0.001) were associated with an increased risk of NTM disease. There was no difference in the risk of NTM according to ICS type. ICS use may increase the risk of developing NTM disease in patients with COPD. Physicians should weigh the potential benefits and risks of ICS, especially when using high doses and prolonged durations.

Differential effects of sex on tuberculosis location and severity across the lifespan.

Disparities exist between sexes regarding tuberculosis (TB) incidence, as well as disease severity and outcome. Using a nationwide TB registry database, we explored the impact of sex and age on extrapulmonary TB (EPTB) among all enrolled patients by (1) calculating the female proportion for every age category according to TB-affected locations, (2) calculating the proportions of EPTB stratified by sex according to age, (3) conducting multivariable analysis to examine the impact of sex and age on EPTB likelihood, and (4) assessing the odds of EPTB for female compared to male as reference in every age category. Further, we explored the impact of sex and age on disease severity among pulmonary TB (PTB) patients. Of all the TB patients, 40.1% were female, with a male-to-female ratio of 1.49. The proportion of females was lowest in their fifties, resembling a U-shape. The male-to-female ratios in PTB and EPTB were 1.67 and 1.03, respectively. Compared to men, women were significantly associated with EPTB in their forties, fifties, and sixties. Female patients with PTB had significantly lower odds of having cavitation and positive smear test results in their fifties. Significant differences were found concerning TB location and severity between sexes, especially during reproductive age.

Development of a daily predictive model for the exacerbation of chronic obstructive pulmonary disease.

Acute exacerbation (AE) of chronic obstructive pulmonary disease (COPD) compromises health status; it increases disease progression and the risk of future exacerbations. We aimed to develop a model to predict COPD exacerbation. We merged the Korean COPD subgroup study (KOCOSS) dataset with nationwide medical claims data, information regarding weather, air pollution, and epidemic respiratory virus data. The Korean National Health and Nutrition Examination Survey (KNHANES) dataset was used for validation. Several machine learning methods were employed to increase the predictive power. The development dataset consisted of 590 COPD patients enrolled in the KOCOSS cohort; these were randomly divided into training and internal validation subsets on the basis of the individual claims data. We selected demographic and spirometry data, medications for COPD and hospital visit for AE, air pollution data and meteorological data, and influenza virus data as contributing factors for the final model. Six machine learning and logistic regression tools were used to evaluate the performance of the model. A light gradient boosted machine (LGBM) afforded the best predictive power with an area under the curve (AUC) of 0.935 and an F1 score of 0.653. Similar favorable predictive performance was observed for the 2151 individuals in the external validation dataset. Daily prediction of the COPD exacerbation risk may help patients to rapidly assess their risk of exacerbation and will guide them to take appropriate intervention in advance. This might lead to reduction of the personal and socioeconomic burdens associated with exacerbation.