Combined effect of changes in NO2, O3, PM2.5, SO2 and CO concentrations on small airway dysfunction.

BACKGROUND AND OBJECTIVE: When multiple complex air pollutants are combined in real-world settings, the reliability of estimating the effect of a single pollutant is questionable. This study aimed to investigate the combined effects of changes in air pollutants on small airway dysfunction (SAD). METHODS: We analysed Korea National Health and Nutrition Examination Survey (KNHANES) V-VIII database from 2010 to 2018 to elucidate the associations between annual changes in air pollutants over a previous 5-year period and small airway function. We estimated the annual concentrations of five air pollutants: NO2, O3, PM2.5, SO2 and CO. Forced expiratory flow between 25% and 75% of vital capacity (FEF25%-75%) <65% was defined as SAD. Using the quantile generalized-Computation (g-Computation) model, the combined effect of the annual changes in different air pollutants was estimated. RESULTS: A total of 29,115 individuals were included. We found significant associations between SAD and the quartiles of annual changes in NO2 (OR = 1.10, 95% CI = 1.08-1.12), O3 (OR = 1.03, 95% CI = 1.00-1.05), PM2.5 (OR = 1.03, 95% CI = 1.00-1.05), SO2 (OR = 1.04, 95% CI = 1.02-1.08) and CO (OR = 1.16, 95% CI = 1.12-1.19). The combined effect of the air pollutant changes was significantly associated with SAD independent of smoking (OR = 1.31, 95% CI = 1.26-1.35, p-value <0.001), and this trend was consistently observed across the entire study population and various subgroup populations. As the estimated risk of SAD, determined by individual-specific combined effect models, increased and the log odds for SAD increased linearly. CONCLUSION: The combined effect of annual changes in multiple air pollutant concentrations were associated with an increased risk of SAD.

Clinical outcomes of long-term inhaled combination therapies in patients with bronchiectasis and airflow obstruction.

BACKGROUND AND OBJECTIVES: Few studies have reported which inhaled combination therapy, either bronchodilators and/or inhaled corticosteroids (ICSs), is beneficial in patients with bronchiectasis and airflow obstruction. Our study compared the efficacy and safety among different inhaled combination therapies in patients with bronchiectasis and airflow obstruction. METHODS: Our retrospective study analyzed the patients with forced expiratory volume in 1 s (FEV1)/forced vital capacity < 0.7 and radiologically confirmed bronchiectasis in chest computed tomography between January 2005 and December 2021. The eligible patients underwent baseline and follow-up spirometric assessments. The primary endpoint was the development of a moderate-to-severe exacerbation. The secondary endpoints were the change in the annual FEV1 and the adverse events. Subgroup analyses were performed according to the blood eosinophil count (BEC). RESULTS: Among 179 patients, the ICS/long-acting beta-agonist (LABA)/long-acting muscarinic antagonist (LAMA), ICS/LABA, and LABA/LAMA groups were comprised of 58 (32.4%), 52 (29.1%), and 69 (38.5%) patients, respectively. ICS/LABA/LAMA group had a higher severity of bronchiectasis and airflow obstruction, than other groups. In the subgroup with BEC ≥ 300/uL, the risk of moderate-to-severe exacerbation was lower in the ICS/LABA/LAMA group (adjusted HR = 0.137 [95% CI = 0.034-0.553]) and the ICS/LABA group (adjusted HR = 0.196 [95% CI = 0.045-0.861]) compared with the LABA/LAMA group. The annual FEV1 decline rate was significantly worsened in the ICS/LABA group compared to the LABA/LAMA group (adjusted ß-coefficient=-197 [95% CI=-307--87]) in the subgroup with BEC < 200/uL. CONCLUSION: In patients with bronchiectasis and airflow obstruction, the use of ICS/LABA/LAMA and ICS/LABA demonstrated a reduced risk of exacerbation compared to LABA/LAMA therapy in those with BEC ≥ 300/uL. Conversely, for those with BEC < 200/uL, the use of ICS/LABA was associated with an accelerated decline in FEV1 in comparison to LABA/LAMA therapy. Further assessment of BEC is necessary as a potential biomarker for the use of ICS in patients with bronchiectasis and airflow obstruction.

Rapid FEV1/FVC Decline Is Related With Incidence of Obstructive Lung Disease and Mortality in General Population.

BACKGROUND: Forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) naturally decreases with age; however, an excessive decline may be related with increased morbidity and mortality. This study aimed to evaluate the FEV1/FVC decline rate in the Korean general population and to identify whether rapid FEV1/FVC decline is a risk factor for obstructive lung disease (OLD) and all-cause and respiratory mortality. METHODS: We evaluated individuals aged 40-69 years who underwent baseline and biannual follow-up spirometric assessments for up to 18 years, excluding those with airflow limitations at baseline. Based on the quartiles of the annual FEV1/FVC decline rate, the most negative FEV1/FVC change (1st quartile of annual FEV1/FVC decline rate) was classified as rapid FEV1/FVC decline. We investigated the risk of progression to OLD and all-cause and respiratory mortality in individuals with rapid FEV1/FVC decline. RESULTS: The annual FEV1/FVC decline rate in the eligible 7,768 patients was 0.32 percentage point/year. The incidence rate of OLD was significantly higher in patients with rapid FEV1/FVC decline than in those with non-rapid FEV1/FVC decline (adjusted incidence rate, 2.119; 95% confidence interval [CI], 1.932-2.324). Rapid FEV1/FVC decline was an independent risk factor for all-cause mortality (adjusted hazard [HR], 1.374; 95% CI, 1.105-1.709) and respiratory mortality (adjusted HR, 1.353; 95% CI, 1.089-1.680). CONCLUSION: The annual FEV1/FVC decline rate was 0.32%p in the general population in Korea. The incidence rate of OLD and the hazards of all-cause and respiratory mortality were increased in rapid FEV1/FVC decliners.

Association between oxygen saturation level during bronchoscopy and post-bronchoscopy adverse events: a retrospective cohort study.

BACKGROUND: Flexible bronchoscopy is widely used to diagnose and treat various respiratory diseases. However, caution is warranted for post-bronchoscopy adverse events. Although desaturation frequently occurs during bronchoscopy, its clinical impact and the optimal oxygen saturation level during the procedure remain unclear. This study aimed to investigate whether the percutaneous oxygen saturation (SpO2) level during bronchoscopy is associated with the development of post-bronchoscopy respiratory adverse events. METHODS: In this single-center retrospective cohort study conducted from March 2020 to February 2021, 569 patients were classified into high or low oxygen saturation groups based on the SpO2 level during bronchoscopy. The primary outcome was post-bronchoscopy respiratory adverse events, and secondary outcomes were other post-bronchoscopy adverse events and clinical outcomes. RESULTS: Among 569 patients, 458 and 111 patients were classified into the high oxygen saturation (SpO2 > 96%) and low oxygen saturation (SpO2 ≤ 94%) groups, respectively. After propensity score matching, the low oxygen saturation group had more post-bronchoscopy respiratory and febrile adverse events than the high oxygen saturation group. In the multivariable regression analysis, low SpO2 level during bronchoscopy was an independent risk factor for post-bronchoscopy respiratory adverse events (odds ratio = 3.16 [95% confidence interval 1.37-7.30]). In the low oxygen saturation group, the high-risk subgroups for post-bronchoscopy respiratory adverse events were the elderly, women, current smokers, and patients with chronic obstructive pulmonary disease or acute decompensated heart failure before bronchoscopy. There was no significant difference in the length of hospital stay, intensive care unit admission, or mortality between the high and low oxygen saturation groups. CONCLUSIONS: Close monitoring is recommended for patients with SpO2 ≤ 94% during bronchoscopy due to the increased risk of respiratory adverse events after the procedure.

Genome-wide association study of non-tuberculous mycobacterial pulmonary disease.

BACKGROUND: The prevalence of non-tuberculous mycobacterial pulmonary disease (NTM-PD) is increasing in South Korea and many parts of the world. However, the genetic factors underlying susceptibility to this disease remain elusive. METHODS: To identify genetic variants in patients with NTM-PD, we performed a genome-wide association study with 403 Korean patients with NTM-PD and 306 healthy controls from the Healthy Twin Study, Korea cohort. Candidate variants from the discovery cohort were subsequently validated in an independent cohort. The Genotype-Tissue Expression (GTEx) database was used to identify expression quantitative trait loci (eQTL) and to conduct Mendelian randomisation (MR). RESULTS: We identified a putatively significant locus on chromosome 7p13, rs849177 (OR, 2.34; 95% CI, 1.71 to 3.21; p=1.36×10-7), as the candidate genetic variant associated with NTM-PD susceptibility. Its association was subsequently replicated and the combined p value was 4.92×10-8. The eQTL analysis showed that a risk allele at rs849177 was associated with lower expression levels of STK17A, a proapoptotic gene. In the MR analysis, a causal effect of STK17A on NTM-PD development was identified (ß, -4.627; 95% CI, -8.768 to -0.486; p=0.029). CONCLUSIONS: The 7p13 genetic variant might be associated with susceptibility to NTM-PD in the Korean population by altering the expression level of STK17A.

Comparison of QuantiFERON-TB Gold Plus and QuantiFERON-TB Gold In-Tube tests for patients with active and latent tuberculosis: A prospective cohort study.

INTRODUCTION: We aimed to determine the diagnostic performance and clinical value of the QuantiFERON-TB Gold In-Tube (QFT-GIT) and QuantiFERON-TB Gold Plus (QFT-Plus) tests in patients with active tuberculosis (TB) or latent TB infection (LTBI). METHODS: We prospectively enrolled 140 patients, including 63 with active TB and 77 with LTBI, between March 2017 and October 2018. QFT-GIT and QFT-Plus were performed simultaneously in all subjects. RESULTS: QFT-Plus and QFT-GIT test results showed significant agreement, in both active TB and LTBI patients, in terms of the interferon-γ concentration and interpretation result. QFT-Plus had higher sensitivity than QFT-GIT for predicting active TB (82.5% vs. 77.8%) and showed fewer false-negative and indeterminate results in both active TB and LTBI patients due to its "TB2 tube". The QFT-Plus TB2-TB1 value was higher in the active TB group than in the LTBI group. The QFT-Plus TB1-Nil and TB2-Nil values were useful in predicting remote LTBI, rather than recent LTBI. CONCLUSIONS: QFT-Plus showed good agreement with QFT-GIT in both active TB and LTBI patients, and higher sensitivity for predicting active TB than QFT-GIT. The QFT-Plus TB2 tube results, which reflect CD8+ T cell immunity, may improve predictive accuracy and detection of the immune response associated with active TB and LTBI.

The Impact of Erosive Reflux Esophagitis on the Decline of Lung Function in the General Population.

BACKGROUND: The impact of reflux esophagitis on the decline of lung function has been rarely reported. This study was performed to evaluate the association between erosive reflux esophagitis and lung function changes. METHODS: We included patients with normal lung function who underwent esophagogastroduodenoscopy for health screening from a health screening center. Patients with persistent erosive reflux esophagitis on two discrete endoscopic examinations were designated as the erosive reflux esophagitis group. We also selected patients without erosive reflux esophagitis and matched them 1:4 with patients from the erosive reflux esophagitis group. We estimated annual forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) changes from baseline and compared these estimates by the linear mixed regression model. We also estimated the biannual incidence of chronic obstructive pulmonary disease (COPD). RESULTS: In total, 1,050 patients (210 patients with erosive reflux esophagitis, and 840 matched controls) were included. The median follow-up duration for spirometry was six years. In patients with erosive reflux esophagitis, mild reflux esophagitis (A grade) was most common (165 patients, 78.6%). The adjusted annual FEV1 change in patients with erosive reflux esophagitis was -51.8 mL/yr, while it decreased by 46.8 mL/yr in controls (P = 0.270). The adjusted annual FVC decline was similar between the two groups (-55.8 vs. -50.5 mL/yr, P = 0.215). The estimated COPD incidence during the follow-up period was not different between the erosive reflux esophagitis and control groups. CONCLUSION: In patients with normal lung function, the presence of erosive reflux esophagitis did not affect the annual declines in FEV1 or FVC.

Clinical and Virologic Effectiveness of Remdesivir Treatment for Severe Coronavirus Disease 2019 (COVID-19) in Korea: a Nationwide Multicenter Retrospective Cohort Study.

BACKGROUND: Remdesivir is widely used for the treatment of coronavirus disease 2019 (COVID-19), but controversies regarding its efficacy still remain. METHODS: A retrospective cohort study was conducted to evaluate the effect of remdesivir on clinical and virologic outcomes of severe COVID-19 patients from June to July 2020. Primary clinical endpoints included clinical recovery, additional mechanical ventilator (MV) support, and duration of oxygen or MV support. Viral load reduction by hospital day (HD) 15 was evaluated by calculating changes in cycle threshold (Ct) values. RESULTS: A total of 86 severe COVID-19 patients were evaluated including 48 remdesivir-treated patients. Baseline characteristics were not significantly different between the two groups. Remdesivir was administered an average of 7.42 days from symptom onset. The proportions of clinical recovery of the remdesivir and supportive care group at HD 14 (56.3% and 39.5%) and HD 28 (87.5% and 78.9%) were not statistically different. The proportion of patients requiring MV support by HD 28 was significantly lower in the remdesivir group than in the supportive care group (22.9% vs. 44.7%, P = 0.032), and MV duration was significantly shorter in the remdesivir group (average, 1.97 vs. 5.37 days; P = 0.017). Analysis of upper respiratory tract specimens demonstrated that increases of Ct value from HD 1-5 to 11-15 were significantly greater in the remdesivir group than the supportive care group (average, 10.19 vs. 5.36; P = 0.007), and the slope of the Ct value increase was also significantly steeper in the remdesivir group (average, 5.10 vs. 2.68; P = 0.007). CONCLUSION: The remdesivir group showed clinical and virologic benefit in terms of MV requirement and viral load reduction, supporting remdesivir treatment for severe COVID-19.

Sequential Analysis of Viral Load in a Neonate and Her Mother Infected With Severe Acute Respiratory Syndrome Coronavirus 2.

We report changes in viral load over time in a 27-day-old neonate with coronavirus disease 2019 who presented with fever, cough, and vomiting. Severe acute respiratory syndrome coronavirus 2 RNA was detected in the nasopharynx, oropharynx, stool, saliva, plasma, and urine. The highest viral RNA copies in nasopharynx decreased over time while viral load in stool remained high.

Pulmonary function is associated with fibrosis severity in patients with biopsy-proven nonalcoholic fatty liver disease.

BACKGROUND & AIMS: The association between nonalcoholic fatty liver disease (NAFLD) and pulmonary function remains elusive because of the heterogeneous spectrum and inaccurate diagnostic methods of NAFLD, and insufficient pulmonary function data. We conducted this study to identify the association between histological severity of NAFLD and pulmonary function. METHODS: This study included patients ≥18 years old with baseline pulmonary function data between August 2014 and July 2019 within a biopsy-evaluated prospective NAFLD cohort. Cross-sectionally, pre-/post-bronchodilator spirometric data with diffusing capacity (DLCO ) were compared according to histological severity of NAFLD in the various demographic and metabolic subgroups. Multivariable-adjusted analysis revealed specific histological features associated with reduced pulmonary function. RESULTS: In a total of 420 patients with biopsy-proven NAFLD, pre-/post-bronchodilator forced vital capacities (FVCs; a percentage of the predictive value) were inversely correlated with histological severity of NAFLD. Conversely, pre-bronchodilator forced expiratory volume in 1 second (FEV1 )/FVC was positively correlated with NAFLD severity. Post-bronchodilator FVC (%) decreased and DLCO /alveolar volume (VA ) increased linearly with worsening histological severity of NAFLD in multivariable analysis. In particular, fibrosis stage remained a significant independent predictor of decreased post-bronchodilator FVC (%) (ß-coefficient, 4.41; 95% confidence interval [-8.39, -0.43]; P = .031) even after adjusted for clinical variables, exclusively in age <65 years, female, never-smoker and nonchronic obstructive pulmonary disease subgroups. CONCLUSIONS: Pulmonary function deteriorates with worsening histological severity of NAFLD, especially at the fibrosis stage. The common pathogenesis of reduced pulmonary function and NAFLD fibrosis progression should be further explored.

Clinical Characteristics of COVID-19: Clinical Dynamics of Mild Severe Acute Respiratory Syndrome Coronavirus 2 Infection Detected by Early Active Surveillance.

BACKGROUND: There is limited information describing the presenting characteristics and dynamic clinical changes in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection diagnosed in the early phase of illness. This study is a case series of patients with coronavirus disease 2019 (COVID-19) admitted to 11 hospitals in Korea. METHODS: Patients with confirmed SARS-CoV-2 infection by positive polymerase chain reaction (PCR) testing of respiratory specimens by active surveillance that were finally discharged between February 20 and April 30, 2020 were included. Patients were classified into mild and non-mild groups on initial admission according to oxygen demand and Sequential Organ Failure Assessment score, and the mild group was followed up and subgrouped into non-aggravation and aggravation groups. RESULTS: A total of 161 patients with SARS-CoV2 infection were enrolled. Among the mild group of 136 patients, 11.7% of patients experienced clinical aggravation during hospitalization, but there was no initial clinical parameter on admission predicting their aggravation. Fever (odds ratio [OR], 4.56), thrombocytopenia (OR, 12.87), fever (OR, 27.22) and lactate dehydrogenase (LDH) > 300 U/L (OR, 18.35), and CRP > 1 mg/dL (OR, 11.31) significantly indicated aggravation in the 1st, 2nd, 3rd, and 4th 5-day periods, respectively. PCR positivity lasted for a median of 22 days and 32 days after the onset of illness in the non-aggravation and aggravation groups, respectively. CONCLUSION: Old age was associated with early severe presentation. Clinical aggravation among asymptomatic or mild patients could not be predicted initially but was heralded by fever and several laboratory markers during the clinical course.

Early discontinuation of ethambutol in pulmonary tuberculosis treatment based on results of the GenoType MTBDRplus assay: A prospective, multicenter, non-inferiority randomized trial in South Korea.

No studies have investigated whether discontinuation of ethambutol (EMB) based on the susceptibility to isoniazid and rifampin as determined by the GenoType MTBDRplus assay would be appropriate. We aimed to determine the feasibility of discontinuing EMB before the end of intensive phase treatment based on the result of MTBDRplus assay in patients with pulmonary tuberculosis (PTB). This prospective, multicenter non-inferiority randomized trial was conducted at 12 referral centers in South Korea in drug-susceptible PTB patients who initiated the standard four-drug regimen for PTB. Based on the results of the assay, EMB was discontinued in the MTBDRplus group after the confirmation that M. tuberculosis isolate was susceptible to isoniazid and rifampin. The timepoint for EMB discontinuation in the Guideline group was determined using the results of the phenotypic drug susceptibility test based on the Korean National TB Guidelines. The primary outcome was treatment success. Secondary outcomes included the 1-year rates of recurrence and adverse events. Of 600 randomized patients, the treatment outcome analysis was performed for 493 patients (MTBDRplus group, 244; Guideline group, 249). Treatment success rates were 93.9% (229/224) in the MTBDRplus group and 93.6% (233/249) in the Guideline group and did not differ between groups; relative risk 1.00 (95% CI 0.95-1.06). The 1-year recurrence rate between the two groups (0.9% vs. 0.5%, respectively) and differences in adverse drug reactions did not differ between groups. In conclusion, early discontinuation of EMB based on the results of the MTBDRplus assay did not affect the treatment outcomes in PTB.

The clinical impact of drug-induced hepatotoxicity on anti-tuberculosis therapy: a case control study.

BACKGROUND: There are limited data available on whether drug-induced hepatotoxicity (DIH) affects the clinical outcomes of tuberculosis (TB) treatment. We explored the effects of DIH on the clinical course and outcomes of pulmonary TB. METHODS: In this retrospective cohort study, we included patients with culture-proven pulmonary TB treated in a tertiary hospital from 2013 to 2016. DIH was defined as proposed by the official American Thoracic Society statement. We compared the clinical outcomes of DIH and non-DIH patients. RESULTS: Between January 1, 2013 and December 31, 2016, a total of 168 TB patients were included, and 20 (11.9%) were diagnosed with DIH. These patients were significantly older, had a higher Charlson Comorbidity Index score, exhibited more chronic liver disease, included more chronic alcoholics, and had a lower body mass index than non-DIH patients. We found no significant differences between DIH and non-DIH patients in the 2-month sputum culture conversion rate, the time to sputum culture conversion, treatment outcomes, or total treatment duration. However, the ratio of treatment interruption time to total treatment duration and the proportion of hepatotonic users were significantly higher among DIH patients. CONCLUSION: DIH development during TB treatment does not significantly affect the clinical outcomes of pulmonary TB. However, treatment interruption caused by DIH may increase the risks of future relapse and acquired resistance. Further study is needed.

Implantation of a Matrigel-loaded agarose scaffold promotes functional regeneration of axons after spinal cord injury in rat.

An agarose scaffold can be useful for supporting and guiding injured axons after spinal cord injury (SCI), but the electrophysiological signal of regenerated axon in scaffolds has not yet been determined. The current study investigated whether a Matrigel-loaded agarose scaffold would enhance the regeneration of axons after SCI. Moreover, the functional connectivity of regenerated axons within the channels of the scaffold was evaluated by directly recording motor evoked potentials. Our data showed that the agarose scaffold containing Matrigel can support and enhance linearly organized axon regeneration after SCI. Additionally, motor evoked potentials were successfully recorded from regenerated axons. These results demonstrate that an agarose scaffold loaded with Matrigel could promote the regeneration of axons and guide the reconnection of functional axons after SCI.

The effect of using blood culture bottle of bronchoalveolar larvage fluid in pneumonia.

BACKGROUND: Pneumonia is a primary cause of morbidity and mortality in infectious disease, and increasing antimicrobial resistance has raised concerns of treatment failure. Therefore, we evaluated the value of a blood culture bottle for bronchoalveolar lavage (BAL) samples on pathogen identification and on treatment modification in patients with pneumonia. METHODS: We conducted a prospective study and enrolled 39 patients who were hospitalized for pneumonia. Enrolled patients underwent BAL; a 10-ml aliquot was transferred to a sterile container for standard quantitative culture, and a 5 ml aliquot was transferred to both an aerobic and an anaerobic blood culture bottle. RESULTS: Microbes were detected in all 39 (100 %) specimens and possible pathogens were identified in 34 patients (84.6 %) from BAL blood culture bottles. In contrast, microbes were detected in 10 patients (25.6 %) and possible pathogens were isolated in 8 patients (20.5 %) in BAL fluid using conventional culture methods. Finally, 8 of 39 (20.5 %) patients changed antibiotics according to the BAL blood culture results and pneumonia improved in 6 of these patients. CONCLUSIONS: Using blood culture bottles for BAL sampling in patients with pneumonia is a sensitive method to detect pathogens in order to identify an adequate antibiotic treatment regimen.

The regional association between bronchiectasis and lung cancer in chest CT.

BACKGROUND: Limited studies have examined the association between lung cancer and bronchiectasis (BE). This study evaluated the regional association between BE and lung cancer by analyzing the lobar location of lung cancer in patients with underlying BE. METHODS: This clustered multi-level study enrolled patients who had underlying BE and were newly diagnosed with lung cancer between January 1, 2010 and May 30, 2013 in two referral hospitals in South Korea. By analyzing the presence of lung cancer and underlying BE as event variables at the level of lung lobes on chest computed tomography (CT), we evaluated the association of BE and lung cancer by the locations of the diseases. RESULTS: Eighty-one patients with BE and combined lung cancer were enrolled. Within 486 lung lobes of the patients, combined BE and lung cancer in the same lobe was found in 11 lobes (2.3 %). Using the general estimating equation assuming BE as a risk factor of lung cancer, the results indicated that the prevalence of lung cancer was significantly lower in the lobes with pre-existing BE (ß = -1.09, p-value = 0.001). CONCLUSIONS: Regionally, pre-existing BE was associated with a lower risk of the occurrence of lung cancer in the same lobe.

The Association of BCG Vaccination with Atopy and Asthma in Adults.

INTRODUCTION: There are few studies investigating the association between BCG vaccination and atopy or asthma in adults. OBJECTIVE: We investigated the association between BCG scar and the occurrence of atopy and asthma in Korean adults. METHODS: We carried out a retrospective study of Korean adults who underwent skin prick testing, and, in some cases, spirometry and bronchial provocation tests in a secondary care hospital from April 2010 to February 2011. Atopy status was classified according to allergen/histamine (A/H) ratio of wheal (A/H ratio ≥ 1, atopy; 0 < A/H ratio < 1, intermediate; A/H ratio = 0, non-atopy). A patient with asthma was defined as one who has symptoms compatible with asthma and showed either a positive provocation testing or bronchodilator reversibility. RESULTS: Among 200 participants, neither the presence (intermediate vs. non-atopy: adjusted odds ratio (aOR) 0.83; 95% CI 0.26, 2.60; p = 0.75, atopy vs. non-atopy: aOR 0.89; 95% CI 0.33, 2.37; p = 0.81, respectively). nor the size of BCG scar was significantly associated with atopy status. However, among those patients who underwent either bronchodilator response testing or bronchial provocation testing, the presence of BCG scar (aOR 0.33; CI 0.14, 0.77; p = 0.01) and the size of BCG scar were inversely associated with asthma. (p = 0.01) CONCLUSIONS: We found a significant association between BCG scar and asthmatic status in Korean adults, although there was no significant association between either the presence or size of BCG scar and atopy.

Comparison of levofloxacin versus moxifloxacin for multidrug-resistant tuberculosis.

RATIONALE: Levofloxacin (LFX) and moxifloxacin (MXF) are the two most frequently recommended fluoroquinolones for treatment of patients with multidrug-resistant tuberculosis (MDR-TB). However, studies comparing the effectiveness of LFX and MXF among patients with MDR-TB are lacking. OBJECTIVES: To compare the effectiveness of LFX and MXF in terms of culture conversion after 3 months of treatment for MDR-TB. METHODS: In this prospective multicenter randomized open label trial, we randomly assigned 182 patients with MDR-TB (sensitive to LFX and MXF) to receive either LFX (750 mg/day; 90 patients) or MXF (400 mg/day; 92 patients) with a background drug regimen. The primary outcome was the proportion of patients who achieved sputum culture conversion at 3 months of treatment. Secondary outcomes were time to culture conversion and time to smear conversion, with data censored at 3 months, and the proportions of adverse drug reactions. MEASUREMENTS AND MAIN RESULTS: At 3 months of treatment, 68 (88.3%) of the 77 patients in the LFX group and 67 (90.5%) of the 74 in the MXF group showed conversion to negative sputum cultures (odds ratio for LFX compared with MXF, 0.78; 95% confidence interval, 0.27-2.20). Adverse drug reactions were reported in six patients (7.7%) in the LFX group and four (5.2%) in the MXF group (P = 0.75). CONCLUSIONS: The choice of LFX or MXF for treatment of patients with MDR-TB may not affect sputum culture conversion at 3 months of treatment. Clinical trial registered with www.clinicaltrials.gov (NCT 01055145).

Diffusing capacity as an independent predictor of acute exacerbations in chronic obstructive pulmonary disease.

A weak correlation between diffusing capacity of the lung for carbon monoxide (DLCO) and emphysema has been reported. This study investigated whether impaired DLCO in chronic obstructive pulmonary disease (COPD) is associated with increased risk of acute exacerbation independent of the presence or extent of emphysema. This retrospective cohort study included patients with COPD between January 2004 and December 2019. The participants were divided into four groups based on visually detected emphysema and impaired DLCO. Among 597 patients with COPD, 8.5% had no emphysema and impaired DLCO whereas 36.3% had emphysema without impaired DLCO. Among the four groups, patients with impaired DLCO and emphysema showed a higher risk of moderate-to-severe or severe exacerbation than those with normal DLCO. Impaired DLCO was an independent risk factor for severe exacerbation (hazard ratio, 1.524 [95% confidence interval 1.121-2.072]), whereas the presence of emphysema was not. The risk of moderate-to-severe or severe exacerbation increases with the severity of impaired DLCO. After propensity-score matching for the extent of emphysema, impaired DLCO was significantly associated with a higher risk of moderate-to-severe (p = 0.041) or severe exacerbation (p = 0.020). In patients with COPD and heterogeneous parenchymal abnormalities, DLCO can be considered an independent biomarker of acute exacerbation.

Association between timed up-and-go test and subsequent pneumonia: A cohort study.

BACKGROUND: Sarcopenia is a risk factor for pneumonia in the elderly, and the timed up-and-go test (TUG) can be used as a screening tool for sarcopenia in this population. This study aimed to evaluate the association between TUG test results and future pneumonia or ventilator care. MATERIALS AND METHODS: From the National Health Insurance Service-Senior Cohort database, we identified 19,804 people without neurological diseases who underwent the TUG test in the National Screening Program for Transitional Ages at the age of 66 years during 2007-2008. Gait abnormality was defined as taking 10 s or longer to perform the TUG test. Pneumonia occurrence was defined using the International Classification of Diseases 10th Revision (ICD-10) code for pneumonia (J12-J18, J69), and ventilator care was defined by procedure codes (M5830, M5850, M5867, M5858, M5860, M5859) according to the Healthcare Common Procedure Coding system codes from 2007 to 2015. RESULTS: The mean follow-up period was 7.4 years (standard error, SE 0.02). The incidence rates of pneumonia in the normal and slow TUG groups were 38 and 39.5/1000 person-years, respectively. The slow TUG group did not show a higher risk of pneumonia (adjusted hazard ratio [aHR], 1.042; 95% confidence interval [95% CI], 0.988-1.107]). Regarding ventilator care, the incidence was 4.7 and 5.2 cases per 1,000 person-years in the normal and slow TUG groups, respectively. Slow TUG groups also did not show an increased risk of ventilator occurrence (aHR, 1.136, [95% CI = 0.947-1.363]). CONCLUSION: The TUG test result was not associated with future pneumonia or ventilator care and may not be useful for predicting pneumonia in community-dwelling elderly individuals. Further studies are needed to identify additional functional tools for sarcopenia associated with future pneumonia occurrences.