Association of change in air quality with hospital admission for acute exacerbation of chronic obstructive pulmonary disease in Guangdong, China: A province-wide ecological study.

AIMS: To assess possible effect of air quality improvements, we investigated the temporal change in hospital admissions for acute exacerbations of chronic obstructive pulmonary disease (AECOPD) associated with pollutant concentrations. METHODS: We collected daily concentrations of particulate matter (i.e., PM2.5, PM10 and PMcoarse), sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), ozone (O3), and admissions for AECOPD for 21 cities in Guangdong from 2013 to 2017. We examined the association of air pollution with AECOPD admissions using two-stage time-series analysis, and estimated the annual attributable fractions, numbers, and direct hospitalization costs of AECOPD admissions with principal component analysis. RESULTS: From 2013-2017, mean daily concentrations of SO2, PM10 and PM2.5 declined by nearly 40%, 30%, and 26% respectively. As the average daily 8 h O3 concentration increased considerably, the number of days exceeding WHO target (i.e.,100 µg/m³) increased from 103 in 2015-152 in 2017. For each interquartile range increase in pollutant concentration, the relative risks of AECOPD admission at lag 0-3 were 1.093 (95% CI 1.06-1.13) for PM2.5, 1.092 (95% CI 1.08-1.11) for O3, and 1.092 (95% CI 1.05-1.14) for SO2. Attributable fractions of AECOPD admission advanced by air pollution declined from 9.5% in 2013 to 4.9% in 2016, then increased to 6.0% in 2017. A similar declining trend was observed for direct AECOPD hospitalization costs. CONCLUSION: Declined attributable hospital admissions for AECOPD may be associated with the reduction in concentrations of PM2.5, PM10 and SO2 in Guangdong, while O3 has emerged as an important risk factor. Summarizes the main finding of the work： Reduction in PM may result in declined attributable hospitalizations for AECOPD, while O3 has emerged as an important risk factor following an intervention.

Association of diurnal temperature range with daily hospitalization for exacerbation of chronic respiratory diseases in 21 cities, China.

BACKGROUND: The association between diurnal temperature range (DTR) and hospitalization for exacerbation of chronic respiratory diseases (CRD) was rarely reported. OBJECTIVES: To examine the association between DTR and daily hospital admissions for exacerbation of CRD and find out the potential effect of modifications on this association. METHOD: Data on daily hospitalization for exacerbation of chronic obstructive pulmonary disease (COPD), asthma and bronchiectasis and meteorology measures from 2013 through 2017 were obtained from 21 cities in South China. After controlling the effects of daily mean temperature, relative humidity (RH), particulate matter < 2.5 µm diameter (PM2.5) and other confounding factors, a standard generalized additive model (GAM) with a quasi-Poisson distribution was performed to evaluate the relationships between DTR and daily hospital admissions of CRD in a two-stage strategy. Subgroup analysis was performed to find potential modifications, including seasonality and population characteristics. RESULT: Elevated risk of hospitalization for exacerbation of CRD (RR = 1.09 [95%CI: 1.08 to 1.11]) was associated with the increase in DTR (the 75th percentile versus the 25th percentile of DTR at lag0-6). The effects of DTR on hospital admissions for CRD were strong at low DTR in the hot season and high DTR in the cold season. The RR (the 75th percentile versus the 25th percentile of DTR at lag0-6) of hospitalization was 1.11 (95%CI: 1.08 to 1.12) for exacerbations of COPD and 1.09 (95%CI: 1.05 to 1.13) for asthma. The adverse effect of DTR on hospitalization for bronchiectasis was only observed in female patients (RR = 1.06 [95%CI: 1.03 to 1.10]). CONCLUSION: Our study provided additional evidence for the association between DTR and daily hospitalization for exacerbation of CRD, and these associations are especially stronger in COPD patients and in the cold season than the hot season. Preventive measures to reduce the adverse impacts of DTR were needed for CRD patients.

Identification and verification of pivotal genes promoting the progression of atherosclerosis based on WGCNA.

As the main pathological basis for the development of cardiovascular and cerebrovascular diseases, atherosclerosis (AS) seriously affects human health. The key targets of biological information analysis of AS can help exploit therapeutic targets. The expression data of early and progressive atherosclerotic tissues were downloaded from the Gene Expression Omnibus (GEO) database. Based on GSE28829 and GSE120521, 74 key genes were obtained through differential expression analysis and weighted correlation network analysis (WGCNA) analysis, which were mainly enriched in the regulating of inflammatory response, chemokine signalling pathway, apoptosis, lipid and AS, Toll-like receptor signalling pathway and so on according to the results of the enrichment analysis. Cytoscape software was applied to screen four pivotal genes (TYROBP, ITGB2, ITGAM and TLR2) based on PPI. The results of the correlation analysis showed that the expression level of pivotal genes was positively related to macrophages M0, and was negatively related to T cells follicular helper. In addition, the expression of ITGB2 was positively related to Tregs. In this study, bioinformatics was applied to screen pivotal genes affecting the progress of AS, which were significantly related to immune-related biological functions and signal pathways of atherosclerotic tissues and the infiltration level of immune cells. Therefore, pivotal genes were expected to become therapeutic targets for AS.

Impaired exercise capacity in individuals with non-obstructive small airway dysfunction.

Background: Whether individuals with non-obstructive spirometry-defined small airway dysfunction (SAD) have impaired exercise capacity is unclear, particularly in never-smokers. This study clarifies the degree of impaired exercise capacity and its potential cause in individuals with non-obstructive SAD. Methods: This community-based, multiyear cross-sectional study analyzed data collected in Guangdong, China from 2012-2019 by the National Science and Technology Support Plan Program. Measurements of exercise capacity [peak work rate and peak oxygen uptake ( V ˙ O 2peak )] in participants with non-obstructive spirometry-defined SAD (n=157) were compared with those in controls (n=85) and Global Initiative for Chronic Obstructive Lung Disease (GOLD) I patients (n=239). Subgroup analyses were performed by smoking status. Results: The risk of impaired exercise capacity was significantly higher in participants with non-obstructive SAD [ V ˙ O 2peak <84%predicted, adjusted odds ratio (aOR) =2.53; 95% confidence interval (CI): 1.42-4.52] than in controls but was not significantly different from that in GOLD I patients. Results were consistent within subgroups of smoking status (ever-smokers: non-obstructive SAD vs. controls, aOR =2.44; 95% CI: 1.08-5.51; never-smokers: non-obstructive SAD vs. controls, aOR =2.38, 95% CI: 1.02-5.58). Participants with non-obstructive SAD had a significantly lower peak work rate (ß=-10.5; 95% CI: -16.3 to -4.7) and V ˙ O 2peak (%predicted, ß=-4.0; 95% CI: -7.7 to -0.2) and tended to have higher ventilatory equivalents for carbon dioxide at the ventilatory threshold ( V ˙ E / V ˙ CO 2AT , ß=1.1; 95% CI: -0.1 to 2.3) when compared with controls. Both peak work rate and V ˙ O 2peak were negatively correlated with V ˙ E / V ˙ CO 2AT . Conclusions: Although not meeting the current criteria for chronic obstructive pulmonary disease, individuals with non-obstructive SAD have impaired exercise capacity that may be associated with ventilatory inefficiency regardless of smoking status.

Traffic-related air pollution is a risk factor in the development of chronic obstructive pulmonary disease.

Background: Outdoor traffic-related air pollution has negative effects on respiratory health. In this study, we aimed to explore the effect of outdoor traffic-related air pollution on chronic obstructive pulmonary disease (COPD) in Guangzhou. Methods: We enrolled 1,460 residents aged 40 years or older between 21 January 2014 and 31 January 2018. We administered questionnaires and spirometry tests. The distance of participants' residences or locations of outdoor activities from busy roads (as indicators of outdoor traffic-related air pollution), indoor air pollution, and smoking history were queried in the questionnaires. Results: Of the 1,460 residents with valid survey and test results, 292 were diagnosed with COPD, with a detection rate of 20%. Participants who lived and did their outdoor activities near busy roads had a higher detection rate of COPD. Among residents living at distances of <50 meters, 50-199 meters, and more than 200 meters from busy roads, the detection rates were 20.6, 21.2, and 14.8%, respectively; the rates for outdoor activities at these distances were 23.8, 24.5, and 13.7%, respectively (p < 0.05). After adjusting for sex, age, smoking status, family history, and smoking index, the distance of outdoor activities from busy roads was an independent risk factor for COPD. Participants whose outdoor activities were conducted <50 meters and 50-199 meters of main roads had odds ratios of 1.54 (95% confidence interval 1.01-2.36) and 1.84 (95% interval 1.23-2.76) for the risk of COPD in comparison with a distance of more than 200 meters from busy roads. Conclusions: Residents of Guangzhou whose outdoor activities were close to busy roads had a high risk of COPD. Traffic-related air pollution presents a risk to human health and a risk of COPD.

Exposure to biomass smoke induces pulmonary Th17 cell differentiation by activating TLR2 on dendritic cells in a COPD rat model.

Almost three billion people in developing countries are exposed to biomass smoke (BS), which predisposes them to developing chronic obstructive pulmonary disease (COPD). COPD is associated with abnormal innate and adaptive immune responses in the lungs and systemic circulation, but the mechanisms underlying BS-COPD development are uncertain. We investigated the role of dendritic cells (DCs) and interleukin (IL)-17A in BS-COPD. We investigated T helper cell responses in the BS-exposed COPD rat model by flow cytometry, quantitative PCR, and enzyme-linked immunosorbent assays. We conducted ex vivo experiments to determine which antigen-presenting cells induce Th17 cell responses. We evaluated the in vitro effects of BS-related particulate matter (BRPM) (2.5 µm) on the function of bone marrow-derived dendritic cells (BMDCs). We found that BS exposure enhanced Th17 responses in the lungs of the COPD-modelled rats, and the stimulated DCs (but not the macrophages) were sufficient to induce naïve CD4 + T cells to produce IL-17A in ex vivo experiments. BRPM significantly enhanced the maturation and activation of DCs through Toll-like receptor 2 (TLR2), but not TLR4, and induced Th17 responses. Therefore, BS activated lung DCs through TLR2, which led to Th17 responses and emphysema in the rats. This process is possibly therapeutically targetable.

Association of hospital admission for bronchiectasis with air pollution: A province-wide time-series study in southern China.

The relation of acute fluctuations of air pollution to hospital admission for bronchiectasis remained uncertain, and large-scale studies were needed. We collected daily concentrations of particulate matter (PM), sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), ozone (O3), and daily hospitalizations for bronchiectasis for 21 cities across Guangdong Province from 2013 through 2017. We examined their association using two-stage time-series analysis. Our analysis was stratified by specific sub-diagnosis, sex and age group to assess potential effect modifications. Relative risks of hospitalization for bronchiectasis were 1.060 (95%CI 1.014-1.108) for PM10 at lag0-6, 1.067 (95%CI 1.020-1.116) for PM2.5 at lag0-6, 1.038 (95%CI 1.005-1.073) for PMcoarse at lag0-6, 1.058 (95%CI 1.015-1.103) for SO2 at lag0-4, 1.057 (95%CI 1.030-1.084) for NO2 at lag0 and 1.055 (95%CI 1.025-1.085) for CO at lag0-6 per interquartile range increase of air pollution. Specifically, acute fluctuations of air pollution might be a risk factor for bronchiectasis patients with lower respiratory infection but not with hemoptysis. Patients aged ≥65 years, and female patients appeared to be particularly susceptible to air pollution. Acute fluctuations of air pollution, particularly PM may increase the risk of hospital admission for bronchiectasis exacerbations, especially for the patients complicated with lower respiratory infection. This study strengthens the importance of reducing adverse impact on respiratory health of air pollution to protect vulnerable populations.

Tiotropium discontinuation in patients with early-stage COPD: a prospective observational cohort study.

BACKGROUND: Tiotropium improves lung function and ameliorates the annual decline in forced expiratory volume in 1 s (FEV1) after bronchodilator use in patients with mild to moderate chronic obstructive pulmonary disease (COPD). However, whether these benefits persist in patients with early-stage COPD after tiotropium discontinuation is unknown. METHODS: In this prospective cohort observational follow-up study, patients who had completed the Tiotropium in Early-Stage COPD (Tie-COPD) trial were followed for a maximum of 3 years, continuing or discontinuing treatment according to their willingness. The outcomes measured were spirometry parameters, COPD exacerbations, COPD Assessment Test (CAT) scores, Clinical COPD Questionnaire (CCQ) scores, modified Medical Research Council (mMRC) scores and the use of respiratory medications. RESULTS: Out of 376 patients, 262 (126 in the post-placebo group and 136 in the post-tiotropium group) completed the maximum 3-year follow-up after the study medication was withdrawn. After discontinuation, the decrease in FEV1 and forced vital capacity (FVC) did not differ significantly between the two groups, and neither did their annual decline. In addition, the frequency of acute COPD exacerbations and the mMRC scores were similar between the two groups after medication withdrawal. Both the mean CAT and CCQ scores were significantly lower in the post-tiotropium group than in the post-placebo group (p<0.05 for all comparisons) at the 1-year follow-up after withdrawal, but they were not different at the next follow-up. CONCLUSION: Withdrawal of tiotropium treatment in early-stage COPD resulted in difference reduction of both FEV1 and FVC, indicating that treatment should be continued.

Clinical impact of the lower limit of normal of FEV1/FVC on detecting chronic obstructive pulmonary disease: A follow-up study based on cross-sectional data.

BACKGROUND: Criteria of obstruction that establish a diagnosis of COPD have been debated in recent years. We carried out a follow-up study to assess the impact of the new LLN reference equation for Chinese on detecting COPD compared with the traditional 0.7fixed criteria. METHODS: We examined the prevalence and characteristics of airflow limitation for a non-child population using post-bronchodilator airflow with both age-dependent predicted lower limit of the normal value and fixed-ratio spirometric criterion. Questionnaires and spirometry were completed for all eligible subjects during the baseline examination. Participants with inconsistent diagnosis according to the two criteria, normal participants (controls) and COPD patients in stages I or II, were invited to take a cardiopulmonary exercise testing (CPET) examination and follow up for 2-4 years. RESULTS: A total of 5448 (mean age 50.51 ±â€¯13.2 yr) study subjects with acceptable spirometry and complete questionnaire data were included in our final analyses. COPD detection based on LLN was consistent with the GOLD 0.7 fixed-ratio in general, as 51 subjects (0.9%) were underdiagnosed, and 61 subjects (1.1%) were overdiagnosed when using LLN as the reference diagnostic criterion. The underdiagnosed subjects were younger, had more symptoms, more exposure to biofuels and worse FEV1 than the normal group; they also demonstrated a damaged cardiopulmonary reserve capacity and significant FEV1 decline. Except for being older, the overdiagnosed subjects differed little from the normal group. CONCLUSIONS: Individual-dependent LLN appears to better reveal impacts on detecting airflow limitation. Participants underdiagnosed by GOLD criterion should be paid more attention. CLINICAL TRIAL REGISTRATION: ChiCTR-ECS-13004110.