Increased Apolipoprotein B/Apolipoprotein A-I Ratio Is Associated With Decline in Lung Function in Healthy Individuals: The Kangbuk Samsung Health Study.

BACKGROUND: Lung dysfunction and high apolipoprotein B/apolipoprotein A-I (apoB/apoA-I) ratio are both recognized risk factors for cardiovascular disease. However, few studies have examined the association between the apoB/ApoA-I ratio and lung function. Therefore, we investigated whether this ratio is associated with decreased lung function in a large healthy cohort. METHODS: We performed a cohort study on 68,418 healthy Koreans (34,797 males, mean age: 38.1 years) who underwent a health examination in 2019. ApoB/apoA-I ratio was categorized into quartiles. Spirometric values at the fifth percentile in our population were considered the lower limit of normal (LLN), which was used to define lung function impairment. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs), using the lowest quartile as the reference, were estimated to determine lung function impairment. RESULTS: Mean apoB/apoA-I ratio was 0.67 ± 0.21. Subjects with the highest quartile of this ratio had the lowest predicted forced expiratory volume in one second (FEV1%) and forced vital capacity (FVC%) after controlling for covariates (P < 0.001). However, FEV1/FVC ratio was not significantly different among the four quartiles (P = 0.059). Compared with the lowest quartile (Q1, reference), the aORs (95% CI) for FEV1% < LLN across increasing quartiles (from Q2 to Q4) were 1.216 (1.094-1.351), 1.293 (1.156-1.448), and 1.481 (1.311-1.672) (P for trend < 0.001), respectively. Similarly, the aORs for FVC% < LLN compared with the reference were 1.212 (1.090-1.348), 1.283 (1.147-1.436), and 1.502 (1.331-1.695) with increasing quartiles (P for trend < 0.001). However, the aORs for FEV1/FVC < LLN were not significantly different among groups (P for trend = 0.273). CONCLUSION: High apoB/apoA-I ratio was associated with decreased lung function. However, longitudinal follow-up studies are required to validate our findings.

Estimating the prevalence and clinical significance of chronic obstructive pulmonary disease-obstructive sleep apnea overlap in South Korea.

INTRODUCTION: Concurrent obstructive sleep apnea (OSA) and chronic obstructive pulmonary disease (COPD) are referred to as COPD-OSA overlap. We investigated the prevalence and clinical significance of COPD-OSA overlap in the general population of South Korea. METHODS: Data were obtained from the 2019 Korea National Health and Nutrition Examination Survey. Participants ≥40 years of age with complete STOP-Bang questionnaire and spirometry data were included. OSA was presumed in individuals with a STOP-Bang score of ≥3. COPD was determined using forced expiratory volume at 1 s/forced vital capacity <0.7. Participants were classified on the basis of the STOP-Bang score and spirometry findings. Clinical characteristics, comorbidities, and quality of life (using the EuroQoL 5-dimension instrument) were compared between the overlap group and COPD-alone or OSA-alone groups. RESULTS: Among the 3157 participants, 6.9 % demonstrated COPD-OSA overlap. Individuals with OSA alone and COPD alone were 31.8 % and 5.2 %, respectively. The overlap group included more males, ever smokers, and frequent alcohol drinkers than the COPD- or OSA-alone groups. The overlap group had more diagnoses of hypertension, diabetes, and stroke than the COPD-alone group. The risk of anxiety/depression was approximately 2.5 times higher in the overlap group than in the COPD-alone group. COPD-OSA overlap was a significant risk factor for anxiety/depression after adjusting for age, sex, household income, and education levels. CONCLUSION: COPD-OSA overlap is not rare within the general population of South Korea. Patients with overlap showed more comorbidities and higher levels of anxiety/depression than those in the COPD-alone group.

Risk adjustment model for tuberculosis compared to non-tuberculosis mycobacterium or latent tuberculosis infection: Center for Personalized Precision Medicine of Tuberculosis (cPMTb) cohort database.

BACKGROUND: The Center for Personalized Precision Medicine of Tuberculosis (cPMTb) was constructed to develop personalized pharmacotherapeutic systems for tuberculosis (TB). This study aimed to introduce the cPMTb cohort and compare the distinct characteristics of patients with TB, non-tuberculosis mycobacterium (NTM) infection, or latent TB infection (LTBI). We also determined the prevalence and specific traits of polymorphisms in N-acetyltransferase-2 (NAT2) and solute carrier organic anion transporter family member 1B1 (SLCO1B1) phenotypes using this prospective multinational cohort. METHODS: Until August 2021, 964, 167, and 95 patients with TB, NTM infection, and LTBI, respectively, were included. Clinical, laboratory, and radiographic data were collected. NAT2 and SLCO1B1 phenotypes were classified by genomic DNA analysis. RESULTS: Patients with TB were older, had lower body mass index (BMI), higher diabetes rate, and higher male proportion than patients with LTBI. Patients with NTM infection were older, had lower BMI, lower diabetes rate, higher previous TB history, and higher female proportion than patients with TB. Patients with TB had the lowest albumin levels, and the prevalence of the rapid, intermediate, and slow/ultra-slow acetylator phenotypes were 39.2%, 48.1%, and 12.7%, respectively. The prevalence of rapid, intermediate, and slow/ultra-slow acetylator phenotypes were 42.0%, 44.6%, and 13.3% for NTM infection, and 42.5%, 48.3%, and 9.1% for LTBI, respectively, which did not differ significantly from TB. The prevalence of the normal, intermediate, and lower transporter SLCO1B1 phenotypes in TB, NTM, and LTBI did not differ significantly; 74.9%, 22.7%, and 2.4% in TB; 72.0%, 26.1%, and 1.9% in NTM; and 80.7%, 19.3%, and 0% in LTBI, respectively. CONCLUSIONS: Understanding disease characteristics and identifying pharmacokinetic traits are fundamental steps in optimizing treatment. Further longitudinal data are required for personalized precision medicine. TRIAL REGISTRATION: This study registered ClinicalTrials.gov NO. NCT05280886.

Do patients attempt and succeed in quitting smoking during tuberculosis treatment? A prospective cohort study.

BACKGROUND: Despite a well-known relation between smoking tobacco and the tuberculosis epidemic, the factors associated with smoking cessation in tuberculosis patients are unclear. This study aims to examine the cascade of smoking cessation and the factors associated with persistent smoking among tuberculosis patients. METHODS: We conducted a prospective cohort study enrolling adult patients with pulmonary tuberculosis between 2016 and 2019 in the Republic of Korea. We examined the smoking status at baseline, followed the current smokers, re-examined their smoking status after 6 months of anti-tuberculosis treatment, and identified the factors associated with persistent smoking. RESULTS: Of the 419 enrolled patients, 109 (26.0%) were current smokers at baseline. Of the 79 current smokers who completed the 6-month survey, 24 (30.4%) succeeded in quitting smoking after 6 months of treatment. The adjusted odds ratio for persistent smoking was 6.57 (95% confidence interval [CI], 1.76-27.83) for drinking and 0.15 (95% CI, 0.03-0.68) for diabetes comorbidity. CONCLUSION: Drinking alcohol and diabetes comorbidity were important factors in smoking cessation. Only one third of the tuberculosis patients in our study cohort succeeded in quitting smoking during the 6-month treatment period. More aggressive interventions for smoking cessation should be adopted within the national anti-tuberculosis program.

Empiric Anti-Pseudomonal ß-Lactam Monotherapy Versus Fluoroquinolone Combination Therapy in Patients With Hospital-Acquired Pneumonia: A Multicenter Cohort Study With Propensity Score Matching.

BACKGROUND: There is insufficient data on the benefits of empiric antibiotic combinations for hospital-acquired pneumonia (HAP). We aimed to investigate whether empiric anti-pseudomonal combination therapy with fluoroquinolones decreases mortality in patients with HAP. METHODS: This multicenter, retrospective cohort study included adult patients admitted to 16 tertiary and general hospitals in Korea between January 1 and December 31, 2019. Patients with risk factors for combination therapy were divided into anti-pseudomonal non-carbapenem ß-lactam monotherapy and fluoroquinolone combination therapy groups. Primary outcome was 30-day mortality. Propensity score matching (PSM) was used to reduce selection bias. RESULTS: In total, 631 patients with HAP were enrolled. Monotherapy was prescribed in 54.7% (n = 345) of the patients, and combination therapy was prescribed in 45.3% (n = 286). There was no significant difference in 30-day mortality between the two groups (16.8% vs. 18.2%, P = 0.729) or even after the PSM (17.5% vs. 18.2%, P = 0.913). After the PSM, adjusted hazard ratio for 30-day mortality from the combination therapy was 1.646 (95% confidence interval, 0.782-3.461; P = 0.189) in the Cox proportional hazards model. Moreover, there was no significant difference in the appropriateness of initial empiric antibiotics between the two groups (55.0% vs. 56.8%, P = 0.898). The proportion of multidrug-resistant (MDR) pathogens was high in both groups. CONCLUSION: Empiric anti-pseudomonal fluoroquinolone combination therapy showed no survival benefit compared to ß-lactam monotherapy in patients with HAP. Caution is needed regarding the routine combination of fluoroquinolones in the empiric treatment of HAP patients with a high risk of MDR.

Comparison of the end-of-life decisions of patients with hospital-acquired pneumonia after the enforcement of the life-sustaining treatment decision act in Korea.

BACKGROUND: Although the Life-Sustaining Treatment (LST) Decision Act was enforced in 2018 in Korea, data on whether it is well established in actual clinical settings are limited. Hospital-acquired pneumonia (HAP) is a common nosocomial infection with high mortality. However, there are limited data on the end-of-life (EOL) decision of patients with HAP. Therefore, we aimed to examine clinical characteristics and outcomes according to the EOL decision for patients with HAP. METHODS: This multicenter study enrolled patients with HAP at 16 referral hospitals retrospectively from January to December 2019. EOL decisions included do-not-resuscitate (DNR), withholding of LST, and withdrawal of LST. Descriptive and Kaplan-Meier curve analyses for survival were performed. RESULTS: Of 1,131 patients with HAP, 283 deceased patients with EOL decisions (105 cases of DNR, 108 cases of withholding of LST, and 70 cases of withdrawal of LST) were analyzed. The median age was 74 (IQR 63-81) years. The prevalence of solid malignant tumors was high (32.4% vs. 46.3% vs. 54.3%, P = 0.011), and the ICU admission rate was lower (42.9% vs. 35.2% vs. 24.3%, P = 0.042) in the withdrawal group. The prevalence of multidrug-resistant pathogens, impaired consciousness, and cough was significantly lower in the withdrawal group. Kaplan-Meier curve analysis revealed that 30-day and 60-day survival rates were higher in the withdrawal group than in the DNR and withholding groups (log-rank P = 0.021 and 0.018). The survival of the withdrawal group was markedly decreased after 40 days; thus, the withdrawal decision was made around this time. Among patients aged below 80 years, the rates of EOL decisions were not different (P = 0.430); however, mong patients aged over 80 years, the rate of withdrawal was significantly lower than that of DNR and withholding (P = 0.001). CONCLUSIONS: After the LST Decision Act was enforced in Korea, a DNR order was still common in EOL decisions. Baseline characteristics and outcomes were similar between the DNR and withholding groups; however, differences were observed in the withdrawal group. Withdrawal decisions seemed to be made at the late stage of dying. Therefore, advance care planning for patients with HAP is needed.

The impact of insulin resistance on the association between metabolic syndrome and lung function: the Kangbuk Samsung Health Study.

BACKGROUND/OBJECTIVE: Metabolic syndrome (MS) is related to lung dysfunction. However, its impact according to insulin resistance (IR) remains unknown. Therefore, we evaluated whether the relation of MS with lung dysfunction differs by IR. SUBJECT/METHODS: This cross-sectional study included 114,143 Korean adults (mean age, 39.6 years) with health examinations who were divided into three groups: metabolically healthy (MH), MS without IR, and MS with IR. MS was defined as presence of any MS component, including IR estimated by HOMA-IR ≥ 2.5. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for lung dysfunction were obtained in MS, MS without IR, and MS with IR groups compared with the MH (reference) group. RESULTS: The prevalence of MS was 50.7%. The percent predicted forced expiratory volume in 1 s (FEV1%) and forced vital capacity (FVC%) showed statistically significant differences between MS with IR and MH and between MS with IR and MS without IR (all P < 0.001). However, those measures did not vary between MH and MS without IR (P = 1.000 and P = 0.711, respectively). Compared to MH, MS was not at risk for FEV1% < 80% (1.103 (0.993-1.224), P = 0.067) or FVC% < 80% (1.011 (0.901-1.136), P = 0.849). However, MS with IR was clearly associated with FEV1% < 80% (1.374 (1.205-1.566) and FVC% < 80% (1.428 (1.237-1.647) (all p < 0.001), though there was no evident association for MS without IR (FEV1%: 1.078 (0.975-1.192, P = 0.142) and FVC%: 1.000 (0.896-1.116, p = 0.998)). CONCLUSION: The association of MS with lung function can be affected by IR. However, longitudinal follow-up studies are required to validate our findings.

Prediction models for respiratory outcomes in patients with COVID-19: integration of quantitative computed tomography parameters, demographics, and laboratory features.

Background: We aimed to develop integrative machine-learning models using quantitative computed tomography (CT) parameters in addition to initial clinical features to predict the respiratory outcomes of coronavirus disease 2019 (COVID-19). Methods: This was a retrospective study involving 387 patients with COVID-19. Demographic, initial laboratory, and quantitative CT findings were used to develop predictive models of respiratory outcomes. High-attenuation area (HAA) (%) and consolidation (%) were defined as quantified percentages of the area with Hounsfield units between -600 and -250 and between -100 and 0, respectively. Respiratory outcomes were defined as the development of pneumonia, hypoxia, or respiratory failure. Multivariable logistic regression and random forest models were developed for each respiratory outcome. The performance of the logistic regression model was evaluated using the area under the receiver operating characteristic curve (AUC). The accuracy of the developed models was validated by 10-fold cross-validation. Results: A total of 195 (50.4%), 85 (22.0%), and 19 (4.9%) patients developed pneumonia, hypoxia, and respiratory failure, respectively. The mean patient age was 57.8 years, and 194 (50.1%) were female. In the multivariable analysis, vaccination status and levels of lactate dehydrogenase, C-reactive protein (CRP), and fibrinogen were independent predictors of pneumonia. The presence of hypertension, levels of lactate dehydrogenase and CRP, HAA (%), and consolidation (%) were selected as independent variables to predict hypoxia. For respiratory failure, the presence of diabetes, levels of aspartate aminotransferase, and CRP, and HAA (%) were selected. The AUCs of the prediction models for pneumonia, hypoxia, and respiratory failure were 0.904, 0.890, and 0.969, respectively. Using the feature selection in the random forest model, HAA (%) was ranked as one of the top 10 features predicting pneumonia and hypoxia and was first place for respiratory failure. The accuracies of the cross-validation of the random forest models using the top 10 features for pneumonia, hypoxia, and respiratory failure were 0.872, 0.878, and 0.945, respectively. Conclusions: Our prediction models that incorporated quantitative CT parameters into clinical and laboratory variables showed good performance with high accuracy.

Clinical phenotypes of chronic cough categorised by cluster analysis.

BACKGROUND: Chronic cough is a heterogeneous disease with various aetiologies that are difficult to determine. Our study aimed to categorise the phenotypes of chronic cough. METHODS: Adult patients with chronic cough were assessed based on the characteristics and severity of their cough using the COugh Assessment Test (COAT) and the Korean version of the Leicester Cough Questionnaire. A cluster analysis was performed using the K-prototype, and the variables to be included were determined using a correlation network. RESULTS: In total, 255 participants were included in the analysis. Based on the correlation network, age, score for each item, and total COAT score were selected for the cluster analysis. Four clusters were identified and characterised as follows: 1) elderly with mild cough, 2) middle-aged with less severe cough, 3) relatively male-predominant youth with severe cough, and 4) female-predominant elderly with severe cough. All clusters had distinct demographic and symptomatic characteristics and underlying causes. CONCLUSIONS: Cluster analysis of age, score for each item, and total COAT score identified 4 distinct phenotypes of chronic cough with significant differences in the aetiologies. Subgrouping patients with chronic cough into homogenous phenotypes could provide a stratified medical approach for individualising diagnostic and therapeutic strategies.

Unilateral diffuse alveolar haemorrhage with microscopic polyangiitis: A case report.

Diffuse alveolar haemorrhage (DAH) is a life-threatening condition caused by widespread damage to the small pulmonary vessels. Common chest imaging findings in patients with DAH show bilateral diffuse airspace opacities. DAH complicating antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis, including microscopic polyangiitis, should be considered as a differential diagnosis in patients with progressive dyspnea, reduced haemoglobin levels, and alveolar opacities on chest imaging. We report the case of a 78-year-old woman who presented with unilateral DAH, severe dyspnea, and anaemia. DAH was confirmed using bronchoalveolar lavage. Laboratory test results, including ANCA, positive anti-myeloperoxidase antibody, and negative anti-proteinase 3, led to a diagnosis of microscopic polyangiitis. Rituximab and methylprednisolone were administered. The patient's symptoms, laboratory test results, and chest radiography findings improved after the initiation of treatment. This case highlights the importance of prompt recognition of clinical symptoms and signs, including dyspnea and anaemia, for the diagnosis of DAH.

Use of the Monoclonal Antibody Regdanvimab to Treat Patients Hospitalized with COVID-19: Real-World Data during the Delta Variant Predominance.

Regdanvimab is the only monoclonal antibody available in Korea that targets severe acute respiratory syndrome coronavirus 2. We retrospectively evaluated the clinical characteristics of 374 adults hospitalized with coronavirus disease 2019 (COVID-19) who were treated with regdanvimab from September through December 2021. In total, 322 (86.1%) patients exhibited risk factors for disease progression. Most patients (91.4%) improved without additional treatment. No patient died or was transferred to intensive care. This study shows that regdanvimab prevented disease progression in high-risk patients with mild to moderate COVID-19 infections during Delta variant predominance.

Impact of nutrition and physical activity on outcomes of hospital-acquired pneumonia.

Frailty is an important risk factor for adverse health-related outcomes. It is classified into several phenotypes according to nutritional state and physical activity. In this context, we investigated whether frailty phenotypes were related to clinical outcome of hospital-acquired pneumonia (HAP). During the study period, a total of 526 patients were screened for HAP and 480 of whom were analyzed. The patients were divided into four groups according to physical inactivity and malnutrition: nutritional frailty (Geriatric Nutritional Risk Index [GNRI] < 82 and Clinical Frailty Scale [CFS] ≥ 4), malnutrition (GNRI < 82 and CFS < 4), physical frailty (GNRI ≥ 82 and CFS ≥ 4), and normal (GNRI ≥ 82 and CFS < 4). Among the phenotypes, physical frailty without malnutrition was the most common (39.4%), followed by nutritional frailty (30.2%), normal (20.6%), and malnutrition (9.8%). There was a significant difference in hospital survival and home discharge among the four phenotypes (p = 0.009), and the nutritional frailty group had the poorest in-hospital survival and home discharge (64.8% and 34.6%, respectively). In conclusion, there were differences in clinical outcomes according to the four phenotypes of HAP. Assessment of frailty phenotypes during hospitalization may improve outcomes through adequate nutrition and rehabilitation treatment of patients with HAP.

Microbiologic pattern and clinical outcome of non-ICU-acquired pneumonia: Korean HAP registry analysis.

BACKGROUND/AIMS: Most studies on hospital-acquired pneumonia (HAP) have been conducted in intensive care unit (ICU) settings. This study aimed to investigate the microbiological and clinical characteristics of non-ICU-acquired pneumonia (NIAP) and to identify the factors affecting clinical outcomes in Korea. METHODS: This multicenter retrospective cohort study was conducted in patients admitted to 13 tertiary hospitals between July 1, 2019 and December 31, 2019. Patients diagnosed with NIAP were included in this study. To assess the prognostic factors of NIAP, the study population was classified into treatment success and failure groups. RESULTS: Of 526 patients with HAP, 379 were diagnosed with NIAP. Overall, the identified causative pathogen rate was 34.6% in the study population. Among the isolated organisms (n = 113), gram-negative bacilli were common pathogens (n = 91), such as Pseudomonas aeruginosa (n = 25), Acinetobacter baumannii (n = 23), and Klebsiella pneumoniae (n = 21). The multidrug resistance rates of A. baumannii, P. aeruginosa, and K. pneumoniae were 91.3%, 76.0%, and 57.1%, respectively. Treatment failure was significantly associated with K. pneumoniae (odds ratio [OR], 3.50; 95% confidence interval [CI], 1.35 to 9.05; p = 0.010), respiratory viruses (OR, 3.81; 95% CI, 1.34 to 10.82; p = 0.012), hematological malignancies (OR, 3.54; 95% CI, 1.57 to 8.00; p = 0.002), and adjunctive corticosteroid treatment (OR, 2.40; 95% CI, 1.27 to 4.52; p = 0.007). CONCLUSION: The causative pathogens of NIAP in Korea are predominantly gram-negative bacilli with a high rate of multidrug resistance. These were not different from the common pathogens of ICU-acquired pneumonia.

Quantitative Computed Tomography Parameters in Coronavirus Disease 2019 Patients and Prediction of Respiratory Outcomes Using a Decision Tree.

Background: Chest computed tomography (CT) scans play an important role in the diagnosis of coronavirus disease 2019 (COVID-19). This study aimed to describe the quantitative CT parameters in COVID-19 patients according to disease severity and build decision trees for predicting respiratory outcomes using the quantitative CT parameters. Methods: Patients hospitalized for COVID-19 were classified based on the level of disease severity: (1) no pneumonia or hypoxia, (2) pneumonia without hypoxia, (3) hypoxia without respiratory failure, and (4) respiratory failure. High attenuation area (HAA) was defined as the quantified percentage of imaged lung volume with attenuation values between -600 and -250 Hounsfield units (HU). Decision tree models were built with clinical variables and initial laboratory values (model 1) and including quantitative CT parameters in addition to them (model 2). Results: A total of 387 patients were analyzed. The mean age was 57.8 years, and 50.3% were women. HAA increased as the severity of respiratory outcome increased. HAA showed a moderate correlation with lactate dehydrogenases (LDH) and C-reactive protein (CRP). In the decision tree of model 1, the CRP, fibrinogen, LDH, and gene Ct value were chosen as classifiers whereas LDH, HAA, fibrinogen, vaccination status, and neutrophil (%) were chosen in model 2. For predicting respiratory failure, the decision tree built with quantitative CT parameters showed a greater accuracy than the model without CT parameters. Conclusions: The decision tree could provide higher accuracy for predicting respiratory failure when quantitative CT parameters were considered in addition to clinical characteristics, PCR Ct value, and blood biomarkers.

Impact of prior vaccination on clinical outcomes of patients with COVID-19.

Fully vaccinated people remain at risk of Coronavirus Disease 2019 (COVID-19). We examined association between prior vaccination and clinical outcomes in patients with COVID-19. Overall, 387 patients with mild-to-severe COVID-19 were enrolled. Patients were considered fully vaccinated at least 14, 7, and 14 days after receiving the second dose of ChAdOx1 nCoV-19 or mRNA-1273, second dose of BNT162b2, or single dose of Ad26.COV2.S, respectively. The primary outcomes (risk of pneumonia, requirement of supplemental oxygen, and progression to respiratory failure) were compared between vaccinated and unvaccinated patients. Logistic regression analysis was performed to identify factors associated with the outcomes. There were 204 and 183 patients in the vaccinated and unvaccinated groups, respectively. The vaccinated group was significantly older and had more comorbidities than the unvaccinated group. Patients in the unvaccinated group were significantly more likely to develop pneumonia (65.6% vs. 36.8%) or require supplemental oxygen (29.0 vs. 15.7%) than the vaccinated group. The vaccinated group had a significantly shorter time from symptom onset to hospital discharge than the unvaccinated group (10 vs. 11 days; p<0.001). The proportion of patients who progressed to respiratory failure did not differ significantly between groups. In multivariable analyses, vaccination was associated with an approximately 70% and 82% lower likelihood of pneumonia and supplemental oxygen requirement, respectively. Being vaccinated was associated with a significantly lower risk of pneumonia and severe disease when breakthrough infection developed. Our findings support continuous efforts to increase vaccine coverage in populations.

The effect of metabolic health and obesity on lung function: A cross sectional study of 114,143 participants from Kangbuk Samsung Health Study.

OBJECTIVE: Although the role of obesity-induced metabolic abnormalities in impaired lung function is well-established, the risk of impaired lung function among obese individuals without metabolic abnormalities, referred to metabolically-healthy obesity (MHO), is largely unexplored. Therefore, we evaluated the impact of MHO on lung function in a large health-screening cohort. METHODS: 114,143 subjects (65,342 men, mean age and BMI: 39.6 years and 23.6) with health examinations in 2019 were divided into four groups as follows: metabolically healthy non-obese (MHNO), MHO, metabolically unhealthy non-obese (MUHNO), and metabolically unhealthy obese (MUHO). Metabolic health was defined as fewer than two metabolic syndrome components. Obesity was defined as BMI ≥25 kg/m2. Adjusted odds ratios (aORs), using MHNO as a reference, were calculated to determine lung function impairment. RESULTS: Approximately one-third (30.6%) of the study subjects were obese. The prevalence of MHO was 15.1%. Subjects with MHO had the highest FEV1% and FVC% values but the lowest FEV1/FVC ratio (p<0.001). These results persisted after controlling for covariates. Compared with MHNO, the aORs (95% confidence interval) for FEV1% < 80% in MHO, MUHNO and MUHO were 0.871 (0.775-0.978), 1.274 (1.114-1.456), and 1.176 (1.102-1.366), respectively (P for trend = 0.014). Similarly, the aORs in MHO, MUHNO, and MUHO were 0.704 (0.615-0.805), 1.241 (1.075-1.432), and 1.226 (1.043-1.441), respectively, for FVC% < 80% (p for trend = 0.013). However, the aORs for FEV1/FVC<0.7 were not significantly different between groups (p for trend = 0.173). CONCLUSIONS: The MHO group had better lung function than other groups. However, longitudinal follow-up studies are required to validate our findings.

Survey of Adverse Events After The First Dose of The ChAdOx1 nCoV-19 Vaccine: A Single-Center Experience in Korea.

Vaccination is an important strategy for controlling the coronavirus disease 2019 (COVID-19) pandemic. We conducted a web-based cross-sectional survey based on Google Forms to collect data on adverse events (AEs) after the first dose of the ChAdOx1 nCoV-19 vaccine for healthcare workers (HCWs). Among the 1,676 vaccinated HCWs, 59.5% (998/1,676) responded to the survey. In total, 809 (81.1%) respondents reported experiencing AEs. There were no serious AEs, such as anaphylaxis. The most common AE was pain at the injection site (76.2%), followed by fatigue (75.9%), myalgia (74.9%), and fever (58.4%). HCWs in the younger age group experienced significantly more AEs than in the older age group.

Isoniazid Population Pharmacokinetics and Dose Recommendation for Korean Patients With Tuberculosis Based on Target Attainment Analysis.

The wide variability of isoniazid (INH) pharmacokinetics is mainly attributed to the trimodal N-acetyltransferase 2 (NAT2) acetylator phenotype, that is, rapid, intermediate, and slow. Consequently, a uniform INH dose in current clinical practice may lead to treatment failure and emergence of drug resistance. There is a lack of studies on specific doses of INH for different NAT2 acetylator phenotypes among tuberculosis (TB) patients. Therefore, we aimed to provide insight into the optimal dosing of INH for each NAT2 acetylator phenotype with respect to the probability of achieving a pharmacokinetic (PK)/pharmacodynamic target. PK, the NAT2 genotype, and clinical data were collected in a multicenter prospective cohort study conducted at 13 clinical centers in Korea. Population PK modeling and simulation were carried out. Data from 454 TB patients were divided into a training data set and a test data set at a ratio of 4 to 1. The PK of the training data were best described by a 2-compartment model with allometric scaling for body size effect. Importantly, NAT2 acetylator phenotypes significantly affected the apparent clearance. Our model, which provided better predictive performance compared with previously published models, was evaluated by external validation using the test set. The simulation for assessing target efficacy and toxicity indicated that the best INH dosing regimens for Korean tuberculosis patients were once-daily doses of 400, 300, and 200 mg for rapid, intermediate, and slow acetylators, respectively. In conclusion, our study provides a step forward in precision dosing for antituberculosis management.

Effect of usual source of care on receiving smoking cessation advice: Korean National Health Panel data analysis.

BACKGROUND: Despite various anti-smoking policies, the smoking rate in adults is still high in Korea. Doctors' advice is known to increase the smoking cessation success rate. However, few studies have reported the effect of having a usual source of care (USC) on receiving smoking cessation advice. OBJECTIVE: To determine the effect of USC on receiving smoking cessation advice. METHODS: We performed multiple panel logistic regression analyses to identify the effect of having a USC on the rate of receiving a doctor's smoking cessation advice using 2009, 2012 and 2013 datasets from the Korea Health Panel database. Only people who responded to questions regarding a USC and smoking cessation advice were analysed. Eventually, 5243 observations were included in the final analysis. RESULTS: A higher percentage of people with a USC received smoking cessation advice from doctors (58.4% in 2009, 64.0% in 2012 and 59.6% in 2013) than those not having a USC (28.6% in 2009, 37.5% in 2012 and 34.8% in 2013). The odds ratios (ORs) of receiving smoking cessation advice in people with a USC were higher than those of people without a USC after performing multiple panel logistic regression analysis with random effects (OR: 2.24; 95% confidence interval: 1.90-2.63). CONCLUSIONS: Having a USC increased the odds of receiving a doctor's smoking cessation advice in Koreans. The results of this study suggest that a health care policy that encourages having a USC is useful in receiving more smoking cessation advice in a Korean population.