Similarity analyses of causative viruses for chronic obstructive pulmonary disease and asthma exacerbations : Author.

BACKGROUND: The representativeness of cohort studies compared to nationwide data is a major concern. This study evaluated the similarity and seasonality of causative respiratory viruses for chronic obstructive pulmonary disease (COPD) and asthma exacerbations between retrospective multicenter cohort study and nationwide data. METHODS: We compared data from the retrospective multicenter cohort study with Korean Influenza and Respiratory Surveillance System data between 2015 and 2018. Correlation, dynamic time warping (DTW), and seasonal autoregressive integrated moving average (SARIMA) analyses were performed. RESULTS: Spearman correlation coefficients [ρ] indicated very strong (respiratory syncytial virus [RSV] [ρ = 0.8458] and influenza virus [IFV] [ρ = 0.8272]), strong (human metapneumovirus [HMPV] [ρ = 0.7177] and parainfluenza virus [PIV] [ρ = 0.6742]), and moderate (rhinovirus [RV] [ρ = 0.5850] and human coronavirus [HCoV] [ρ = 0.5158]) correlations. DTW analyses showed moderate (PIV) and high (IFV, RSV, and HMPV) synchronicity between the two datasets, while RV and HCoV showed low synchronicity. SARIMA analyses revealed 12-month seasonality for IFV, RSV, PIV, and HMPV. The peak season was winter for RSV and IFV, spring to summer for PIV, and spring for HMPV. CONCLUSIONS: This was the first study to report the synchronicity between a retrospective multicenter cohort study of viruses that can cause COPD or asthma exacerbations and nationwide surveillance system data.

Risk of Rapid Lung Function Decline in Young Adults With Chronic Obstructive Pulmonary Disease: A Community-Based Prospective Cohort Study.

It is unclear whether young adults with chronic obstructive pulmonary disease (COPD) are at an increased risk of rapid lung function decline. A total of 2,934 Korean adults aged 40-49 years who had consecutive lung function measurements were included. COPD was defined as pre-bronchodilator forced expiratory volume in 1 second (FEV1)/forced vital capacity < lower limit of normal. The risk of rapid decline in FEV1, defined as ≥ 60 mL/year, was assessed using multivariable logistic regression analysis. In the multivariable model, a significantly higher risk of rapid decline in FEV1 was observed for the COPD group compared with the non-COPD group (adjusted odds ratio, 1.89; 95% confidence interval, 1.18-2.95), which was especially significant in subjects with FEV1 less than the median value (< 110%pred) (Pinteraction = 0.017) and inactive physical activity (Pinteraction = 0.039). In conclusion, the risk of rapid FEV1 decline was higher in young adults with COPD than in those without COPD, especially in those with FEV1 less than the median value and inactive physical activity.

Association between non-cystic fibrosis bronchiectasis and the risk of incident dementia: A nationwide cohort study.

BACKGROUND: Chronic lung diseases, such as chronic obstructive pulmonary disease or asthma, are associated with an increased risk of dementia. However, few data are available regarding the risk of dementia in individuals with bronchiectasis. OBJECTIVES: To explore the association between bronchiectasis and the risk of incident dementia using a longitudinal population-based cohort. METHODS: A total of 4,068,560 adults older than 50 years without previous dementia were enrolled from the Korean National Health Insurance Service database in 2009. They were followed up until the date of the diagnosis of dementia or December 31, 2020. The study exposure was the diagnosis of bronchiectasis, and the primary outcome was incident dementia comprising Alzheimer's disease and vascular dementia. RESULTS: During the median follow-up duration of 9.3 years, the incidence of all-cause dementia was 1.6-fold higher in individuals with bronchiectasis than in those without bronchiectasis (15.0 vs. 9.3/1000 person-years, p < .001). In the multivariable Cox regression analysis, the risk of all dementia was significantly higher in individuals with bronchiectasis than in those without bronchiectasis (adjusted hazard ratio [aHR] 1.09, 95% confidence interval [CI] 1.04-1.14). In a subgroup analysis by dementia type, individuals with bronchiectasis had an increased risk of Alzheimer's disease compared to those without bronchiectasis (aHR 1.07, 95% CI 1.01-1.12); the risk of vascular dementia did not significantly differ between the two groups (aHR 1.05, 95% CI 0.90-1.21). CONCLUSION: Bronchiectasis was associated with an increased risk of dementia, especially Alzheimer's disease.

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

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

Comparison of epidermal growth factor receptor tyrosine kinase inhibitors for patients with lung adenocarcinoma harboring different epidermal growth factor receptor mutation types.

BACKGROUND: Epidermal growth factor receptor (EGFR) mutations in non-small-cell lung cancer predict sensitivity to EGFR tyrosine kinase inhibitors (TKIs). EGFR mutation types are associated with efficacy of EGFR TKIs. We investigated the clinical outcomes of afatinib, erlotinib, and gefitinib according to EGFR mutation type in patients with lung adenocarcinoma. METHODS: Between May 2010 and December 2018, we investigated 363 patients with advanced lung adenocarcinoma harboring EGFR mutations who received EGFR TKIs. Efficacies of EGFR TKIs such as response rate, progression-free survival (PFS), and overall survival (OS) were retrospectively evaluated according to exon 19 deletion (E19del), L858R point mutation (L858R) and uncommon mutations. RESULTS: The frequency of E19del was 48.2%, that of L858R was 42.4%, and that of uncommon mutations was 9.4%. E19del and L858R were associated with superior PFS and OS compared with uncommon mutations. Erlotinib showed significantly inferior OS than other TKIs (30.8 ± 3.3 in erlotinib vs. 39.1 ± 4.3 in afatinib vs. 48.4 ± 6.3 in gefitinib; p = 0.031) in patients with L858R. Gefitinib showed significantly inferior PFS (4.6 ± 1.1 in gefitinib vs. 11.6 ± 2.7 in afatinib vs. 10.6 ± 2.7 in erlotinib; p = 0.049) in patients with uncommon mutations. CONCLUSION: Afatinib was significantly associated with a longer PFS, presenting constant effectiveness in all EGFR mutation types. Caution may be needed on the use of erlotinib for L858R and the use of gefitinib for uncommon EGFR mutations.

Improvement in the survival rates of extracorporeal membrane oxygenation-supported respiratory failure patients: a multicenter retrospective study in Korean patients.

BACKGROUND: Although the utilization of extracorporeal membrane oxygenation (ECMO) is increasing and its technology is evolving, only a few epidemiologic reports have described the uses and outcomes of ECMO. The aim of this study was to investigate the changes in utilization and survival rate in patients supported with ECMO for severe respiratory failure in Korea. METHODS: This was a multicenter study on consecutive patients who underwent ECMO across 16 hospitals in Korea. The records of all patients who required ECMO for acute respiratory failure between 2012 and 2015 were retrospectively reviewed, and the utilization of ECMO was analyzed over time. RESULTS: During the study period, 5552 patients received ECMO in Korea as a whole, and a total of 2472 patients received ECMO at the participating 16 hospitals. We analyzed 487 (19.7%) patients who received ECMO for respiratory failure. The number of ECMO procedures provided for respiratory failure increased from 104 to 153 during the study period. The in-hospital survival rate increased from 30.8% to 35.9%. The use of prone positioning increased from 6.8% to 49.0% (p < 0.001), and the use of neuromuscular blockers also increased from 28.2% to 58.2% (p < 0.001). Multiple regression analysis showed that old age (OR 1.038 (95% CI 1.022, 1.054)), use of corticosteroid (OR 2.251 (95% CI 1.153, 4.397)), continuous renal replacement therapy (OR 2.196 (95% CI 1.135, 4.247)), driving pressure (OR 1.072 (95% CI 1.031, 1.114)), and prolonged ECMO duration (OR 1.020 (95% CI 1.003, 1.038)) were associated with increased odds of mortality. CONCLUSIONS: Utilization of ECMO and survival rates of patients who received ECMO for respiratory failure increased over time in Korea. The use of pre-ECMO prone positioning and neuromuscular blockers also increased during the same period.

Immunoglobulin G Subclass Deficiencies in Adult Patients with Chronic Airway Diseases.

Immunoglobulin G subclass deficiency (IgGSCD) is a relatively common primary immunodeficiency disease (PI) in adults. The biological significance of IgGSCD in patients with chronic airway diseases is controversial. We conducted a retrospective study to characterize the clinical features of IgGSCD in this population. This study examined the medical charts from 59 adult patients with IgGSCD who had bronchial asthma or chronic obstructive pulmonary disease (COPD) from January 2007 to December 2012. Subjects were classified according to the 10 warning signs developed by the Jeffrey Modell Foundation (JMF) and divided into two patient groups: group I (n = 17) met ≥ two JMF criteria, whereas group II (n = 42) met none. IgG3 deficiency was the most common subclass deficiency (88.1%), followed by IgG4 (15.3%). The most common infectious complication was pneumonia, followed by recurrent bronchitis, and rhinosinusitis. The numbers of infections, hospitalizations, and exacerbations of asthma or COPD per year were significantly higher in group I than in group II (P < 0.001, P = 0.012, and P < 0.001, respectively). The follow-up mean forced expiratory volume (FEV1) level in group I was significantly lower than it was at baseline despite treatment of asthma or COPD (P = 0.036). In conclusion, IgGSCD is an important PI in the subset of patients with chronic airway diseases who had recurrent upper and lower respiratory infections as they presented with exacerbation-prone phenotypes, decline in lung function, and subsequently poor prognosis.

Respiratory pathogen and clinical features of hospitalized patients in acute exacerbation of chronic obstructive pulmonary disease after COVID 19 pandemic.

Respiratory infections are common causes of acute exacerbation of chronic obstructive lung disease (AECOPD). We explored whether the pathogens causing AECOPD and clinical features changed from before to after the coronavirus disease 2019 (COVID-19) outbreak. We reviewed the medical records of patients hospitalized with AECOPD at four university hospitals between January 2017 and December 2018 and between January 2021 and December. We evaluated 1180 patients with AECOPD for whom medication histories were available. After the outbreak, the number of patients hospitalized with AECOPD was almost 44% lower compared with before the outbreak. Patients hospitalized with AECOPD after the outbreak were younger (75 vs. 77 years, p = 0.003) and more often stayed at home (96.6% vs. 88.6%, p < 0.001) than patients of AECOPD before the outbreak. Hospital stay was longer after the outbreak than before the outbreak (10 vs. 8 days. p < 0.001). After the COVID-19 outbreak, the identification rates of S. pneumoniae (15.3 vs. 6.2%, p < 0.001) and Hemophilus influenzae (6.4 vs. 2.4%, p = 0.002) decreased, whereas the identification rates of P. aeruginosa (9.4 vs. 13.7%, p = 0.023), Klebsiella pneumoniae (5.3 vs. 9.8%, p = 0.004), and methicillin-resistant Staphylococcus aureus (1.0 vs. 2.8%, p = 0.023) increased. After the outbreak, the identification rate of influenza A decreased (10.4 vs. 1.0%, p = 0.023). After the outbreak, the number of patients hospitalized with AECOPD was lower and the identification rates of community-transmitted pathogens tended to decrease, whereas the rates of pathogens capable of chronic colonization tended to increase. During the period of large-scale viral outbreaks that require quarantine, patients with AECOPD might be given more consideration for treatment against strains that can colonize chronic respiratory disease rather than community acquired pathogens.