MRI analysis of and factors related to knee injuries in amateur marathon runners.

BACKGROUND: Marathons are the most challenging form of running, and amateur athletes may be more prone to injury due to a lack of professional knowledge and instruction in running. PURPOSE: To analyze the MRI manifestations of and factors related to knee injuries in amateur marathon runners. SUBJECTS: Data were collected from a hospital database of 105 qualified amateur marathon athletes (65 males,40 females), between May 2018 and December 2021. FIELD STRENGTH/SEQUENCE: 1.5T MR: sagittal fs-PDWI, sagittal T1WI and sagittal 3D-DESS sequence. ASSESSMENT: The MRI manifestations of knee joint injury were analyzed and evaluated by two radiologists. STATISTICAL TESTS: The inter-observer agreement on MRI readings was analyzed using the kappa coefficient, and binary logistic regression analysis was employed to identify factors associated with knee injuries. RESULTS: The overall prevalence of knee cartilage lesions, meniscus lesions and bone marrow edema among amateur marathon runners was 45.7%, 72.4%, and 49.5% respectively. Our analysis revealed that older age (OR = 1.135, P<0.001), higher BMI (OR = 1.236, P = 0.044), and slower pace (OR = 2.305, P = 0.017) were associated with increased risk of articular cartilage disease. Furthermore, older age (OR = 1.425, P<0.001) was identified as a risk factor for meniscal lesions, while older age (OR = 1.088, P = 0.002) was bone marrow edema. Notably, no significant correlation was observed between knee joint injuries of amateur marathon athletes and gender or the monthly running distance (P>0.05). CONCLUSIONS: The occurrence of knee injuries among amateur marathon athletes was highly prevalent, with the patellofemoral joint cartilage and posterior horn of medial meniscus being frequently affected areas. Moreover, age, BMI, running years and pace were significant risk factors of knee joint injury.

Mediating Effect of Tobacco Dependence on the Association Between Maternal Smoking During Pregnancy and Chronic Obstructive Pulmonary Disease: Case-Control Study.

BACKGROUND: Maternal smoking during pregnancy (MSDP) is a known risk factor for offspring developing chronic obstructive pulmonary disease (COPD), but the underlying mechanism remains unclear. OBJECTIVE: This study aimed to explore whether the increased COPD risk associated with MSDP could be attributed to tobacco dependence (TD). METHODS: This case-control study used data from the nationwide cross-sectional China Pulmonary Health study, with controls matched for age, sex, and smoking status. TD was defined as smoking within 30 minutes of waking, and the severity of TD was assessed using the Fagerstrom Test for Nicotine Dependence. COPD was diagnosed when the ratio of forced expiratory volume in 1 second to forced vital capacity was <0.7 in a postbronchodilator pulmonary function test according to the 2017 Global Initiative for Chronic Obstructive Lung Disease criteria. Logistic regression was used to examine the correlation between MSDP and COPD, adjusting for age, sex, BMI, educational attainment, place of residence, ethnic background, occupation, childhood passive smoking, residential fine particulate matter, history of childhood pneumonia or bronchitis, average annual household income, and medical history (coronary heart disease, hypertension, and diabetes). Mediation analysis examined TD as a potential mediator in the link between MSDP and COPD risk. The significance of the indirect effect was assessed through 1000 iterations of the "bootstrap" method. RESULTS: The study included 5943 participants (2991 with COPD and 2952 controls). Mothers of the COPD group had higher pregnancy smoking rates (COPD: n=305, 10.20%; controls: n=211, 7.10%; P<.001). TD was more prevalent in the COPD group (COPD: n=582, 40.40%; controls: n=478, 33.90%; P<.001). After adjusting for covariates, MSDP had a significant effect on COPD (ß=.097; P<.001). There was an association between MSDP and TD (ß=.074; P<.001) as well as between TD and COPD (ß=.048; P=.007). Mediation analysis of TD in the MSDP-COPD association showed significant direct and indirect effects (direct: ß=.094; P<.001 and indirect: ß=.004; P=.03). The indirect effect remains present in the smoking population (direct: ß=.120; P<.001 and indirect: ß=.002; P=.03). CONCLUSIONS: This study highlighted the potential association between MSDP and the risk of COPD in offspring, revealing the mediating role of TD in this association. These findings contribute to a deeper understanding of the impact of prenatal tobacco exposure on lung health, laying the groundwork for the development of relevant prevention and treatment strategies.

Heterogeneities and impact profiles of early chronic obstructive pulmonary disease status: findings from the China Pulmonary Health Study.

Background: The prevalence, epidemiological and clinical heterogeneities, and impact profiles of individuals with preserved ratio impaired spirometry (PRISm), pre-COPD, young COPD, and mild COPD in general Chinese population were not known yet. Methods: Data were obtained from the China Pulmonary Health study (2012-2015), a nationally representative cross-sectional survey that recruited 50,991 adults aged 20 years or older. Definitions of the four early disease status were consistent with the latest publications and the Global Initiative for Chronic Obstructive Lung Disease criteria. Findings: The age-standardised prevalences of PRISm, pre-COPD, young COPD, and mild COPD were 5.5% (95% confidence interval, 4.3-6.9), 7.2% (5.9-8.8), 1.1% (0.7-1.8), and 3.1% (2.5-3.8), respectively. In summary, mild COPD was under more direct or established impact factor exposures, such as older age, male gender, lower education level, lower family income, biomass use, air pollution, and more accumulative cigarette exposures; young COPD and pre-COPD experienced more personal and parents' events in earlier lives, such as history of bronchitis or pneumonia in childhood, frequent chronic cough in childhood, parental history of respiratory diseases, passive smoke exposure in childhood, and mother exposed to passive smoke while pregnant; pre-COPD coexisted with heavier symptoms and comorbidities burdens; young COPD exhibited worse airway obstruction; and most of the four early disease status harbored small airway dysfunction. Overall, older age, male gender, lower education level, living in the urban area, occupational exposure, frequent chronic cough in childhood, more accumulated cigarette exposure, comorbid with cardiovascular disease and gastroesophageal reflux disease were all associated with increased presence of the four early COPD status; different impact profiles were additionally observed with distinct entities. Over the four categories, less than 10% had ever taken pulmonary function test; less than 1% reported a previously diagnosed COPD; and no more than 13% had received pharmaceutical treatment. Interpretation: Significant heterogeneities in prevalence, epidemiological and clinical features, and impact profiles were noted under varied defining criteria of early COPD; a unified and validated definition for an early disease stage is warranted. Closer attention, better management, and further research need to be administrated to these population. Funding: Chinese Academy of Medical Sciences Institute of Respiratory Medicine Grant for Young Scholars (No. 2023-ZF-9); China International Medical Foundation (No. Z-2017-24-2301); Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences (No. 2021-I2M-1-049); National High Level Hospital Clinical Research Funding (No. 2022-NHLHCRF-LX-01); Major Program of National Natural Science Foundation of China (No. 82090011).

Prevalence and burden of chronic cough in China: a national cross-sectional study.

Background: Chronic cough is a common complaint, but there are no population-based data on its burden in China. We determined the prevalence of chronic cough and its impact on health status in adults stratified by sex, age and the diagnosis of COPD or the presence of small airway dysfunction (SAD). Methods: A representative sample of 57 779 Chinese adults aged 20 years or older was recruited and pulmonary function test was measured. Chronic cough was defined as cough lasting for >3 months in each year. Quality of life was assessed by the 12-item Short Form Health Survey (SF-12), and self-reported history of hospital visits was recorded. Results: Chronic cough was found in 3.6% (95% CI 3.1-4.1) of Chinese adults, 2.4% (95% CI 1.9-3.1) of those aged 20-49 years and 6.0% (95% CI 5.3-6.8) of those aged 50 years or older. Individuals with chronic cough had an impaired physical component summary (PCS) score of the SF-12 (p<0.0001) and more emergency visits (p=0.0042) and hospital admissions (p=0.0002). Furthermore, the impact of chronic cough on PCS score was more significant in those aged 50 years or older, or with COPD (p=0.0018 or 0.0002, respectively), with the impact on hospital admission being more significant in those with COPD or with SAD (p=0.0026 or 0.0065, respectively). Conclusions: Chronic cough is prevalent in China and is associated with a poorer health status, especially in individuals aged 50 years or older and those with the diagnosis of COPD or SAD.

Chronic Obstructive Pulmonary Disease With Asthma-Like Features in the General Population in China.

Background: Patients with features of both asthma and chronic obstructive pulmonary disease (COPD) are seen commonly in the clinic but less is known in the general population. We investigated the prevalence and the heterogeneity of COPD with concomitant features of asthma in Chinese adult population. Methods: COPD was defined as post-bronchodilator ratio of forced expiratory volume in 1s (FEV1) to forced vital capacity of less than the lower limits of normal. COPD with concomitant features of asthma was defined as either COPD with asthma diagnosed by self-reported physician-diagnosis or by presence of current wheeze, or as COPD with high bronchodilator response (HBR) defined as an increase in FEV1 >15% and >400 ml after bronchodilator. Results: COPD with concomitant features of asthma was found in 1.62% (95% CI 1.31-2.00) of adults (≥20 years) or in 15.2% (95% CI 13.0-17.7) of COPD patients. Compared with COPD with HBR, COPD with asthma diagnosis or wheeze were older (61.8 ± 1.1 years vs. 47.4 ± 2.8 years, P < 0.001), and with a lower post-bronchodilator FEV1%pred (68.2 ± 2.3 vs. 96.6 ± 3.4, P < 0.001). Age, smoking status, biomass use and allergic rhinitis were associated with increasing prevalence of COPD with asthma diagnosis or wheeze, and had greater impaired health status, more comorbidities and more acute exacerbations in the preceding 12 months. Conclusions: COPD with concomitant features of asthma is common in people with COPD and those with COPD with asthma diagnosis or wheeze experience worse clinical severity than COPD with HBR. These findings will help toward the definition of the asthma-COPD overlap condition.

Development and Validation of a Screening Questionnaire of COPD from a Large Epidemiological Study in China.

OBJECTIVE: We aimed to establish an easy-to-use screening questionnaire with risk factors and suspected symptoms of COPD for primary health care settings. METHODS: Based on a nationwide epidemiological study of pulmonary health among adults in mainland China (China Pulmonary Health, CPH study) between 2012 and 2015, participants ≥40 years who completed the questionnaire and spirometry tests were recruited and randomly divided into development set and validation set by the ratio of 2:1. Parameters including sex, age, BMI, residence, education, smoking status, smoking pack-years, biomass exposure, parental history of respiratory diseases and daily respiratory symptoms were initially selected for the development of scoring system. Receiver operating characteristic (ROC) curve, area under curve (AUC), positive and negative predictive values were calculated in development set and validation set. RESULTS: After random split by 2:1 ratio, 22443 individuals were assigned to development set and 11221 to validation set. Ten variables were significantly associated with COPD independently in development set after a stepwise selection by multivariable logistic model and used to develop scoring system. The scoring system yielded good discrimination, as measured by AUC of 0.7737, and in the validation set, the AUC was 0.7711. When applying a cutoff point of ≥16, the sensitivity in development set was 0.69 (0.67 - 0.71); specificity 0.72 (0.71 - 0.73), PPV 0.25 (0.24 - 0.26) and NPV 0.94 (0.94 - 0.95). CONCLUSION: We developed and validated a comprehensive screening questionnaire, COPD-CPHS, with good discrimination. The score system still needs to be validated by large cohort in the future.Supplemental data for this article is available online at https://doi.org/10.1080/15412555.2022.2042504 .

Associations of residential greenness with lung function and chronic obstructive pulmonary disease in China.

BACKGROUND: Studies on the association of greenness with respiratory health are scarce in developing countries, and previous studies in China have focused on only one or two indicators of lung function. OBJECTIVE: The study aims to evaluate the associations of residential greenness with full-spectrum lung function indicators and prevalence of chronic obstructive pulmonary disease (COPD). METHODS: This nationwide cross-sectional survey included 50,991 participants from the China Pulmonary Health study. Lung function indicators included four categories: indicators of obstructive ventilatory dysfunction (FEV1, FVC and FEV1/FVC); an indicator of large-airway dysfunction (PEF); indicators of small-airway dysfunction (FEF25-75% and FEV3/FEV6); and other indicators. Residential greenness was assessed by the Normalized Difference Vegetation Index (NDVI). Multivariable linear regression models and logistic regression models were used to analyze associations of greenness with lung function and COPD prevalence. RESULTS: Within the 500 m buffer, an interquartile range (IQR) increase in NDVI was associated with higher FEV1 (24.76 mL), FVC (16.52 mL), FEV1/FVC (0.38), FEF50% (56.34 mL/s), FEF75% (33.43 mL/s), FEF25-75% (60.73 mL/s), FEV3 (18.59 mL), and FEV6 (21.85 mL). However, NDVI was associated with lower PEF. In addition, NDVI was significantly associated with 10% lower odds of COPD. The stratified analyses found that the associations were only significant in middle-young people, females, and nonsmokers. The associations were influenced by geographic regions. CONCLUSIONS: Residential greenness was associated with better lung function and lower odds of COPD in China. These findings provide a scientific basis for healthy community planning.

Long-Term Ozone Exposure and Small Airway Dysfunction: The China Pulmonary Health (CPH) Study.

Rationale: It remains unknown whether long-term ozone exposure can impair lung function. Objectives: To investigate the associations between long-term ozone exposure and adult lung function in China. Methods: Lung function results and diagnosis of small airway dysfunction (SAD) were collected from a cross-sectional study, the China Pulmonary Health Study (N = 50,991). We used multivariable linear and logistic regression models to examine the associations of long-term ozone exposure with lung function parameters and SAD, respectively, adjusting for demographic characteristics, individual risk factors, and longitudinal trends. We then performed a stratification analysis by chronic obstructive pulmonary disease (COPD). Measurements and Main Results: We observed that each 1 SD (4.9 ppb) increase in warm-season ozone concentrations was associated with a 14.2 ml/s (95% confidence interval [CI], 8.8-19.6 ml/s] decrease in forced expiratory flow at the 75th percentile of vital capacity and a 29.5 ml/s (95% CI, 19.6-39.5 ml/s) decrease in mean forced expiratory flow between the 25th and 75th percentile of vital capacity. The odds ratio of SAD was 1.09 (95% CI, 1.06-1.11) for a 1 SD increase in warm-season ozone concentrations. Meanwhile, we observed a significant association with decreased FEV1/FVC but not with FEV1 or FVC. The association estimates were greater in the COPD group than in the non-COPD group. Conclusions: We found independent associations of long-term ozone exposure with impaired small airway function and higher SAD risks, while the associations with airflow obstruction were weak. Patients with COPD appear to be more vulnerable.

MRI study of changes in knee bone marrow edema-like signal in asymptomatic amateur marathon runners before and after half-marathon running.

OBJECTIVE: To evaluate the incidence of knee bone marrow edema-like signal and its changes before and after running a half marathon running in asymptomatic amateur marathon runners to explore the impact of the half marathon on knee bone marrow edema-like signal. METHODS: 50 asymptomatic amateur marathon runners (30 males, 20 females) were recruited. T1-weighted imaging (T1WI), fat-suppressed protein density weighted imaging (fs-PDWI) and three-dimensional double-echo steady-state (3D-DESS) sequence on the right knee were performed before and within 3 h after a half-marathon running. 20 healthy volunteers were recruited as control. According to the whole-organ magnetic resonance imaging score (WORMS) system, the involvement of bone marrow edema-like signal in 15 regions of knee was graded from 0 to 3. The results were classified and Mann Whitney U test was used for comparison between groups. RESULTS: The total incidence of bone marrow edema-like signal in amateur marathon group was 62%. Among them, the incidence of grade 1-3 was 48% (24/50), 12% (6/50), 2% (1/50), respectively, which was statistically significant compared with the controls (P = 0.007). There was no significant difference between gender before running (P = 0.172) and after running (P = 0.162). There was no significant difference before and after running (P > 0.05). However, 3 subjects showed new lesions, 8 subjects showed progression and 4 subjects showed decreased signal. CONCLUSION: The occurrence of knee bone marrow edema-like signal in amateur marathon runners is more common. The lesions of bone marrow edema-like signal will show aggravation or improvement in a certain extent after the half marathon.

Association of fine particulate matter air pollution and its constituents with lung function: The China Pulmonary Health study.

The associations of long-term exposure to various constituents of fine particulate matter (≤2.5 µm in aerodynamic diameter, PM2.5) air pollution with lung function were not clearly elucidated in developing countries. The aim was to evaluate the associations of long-term exposure to main constituents of PM2.5 with lung function in China. This is a nationwide, cross-sectional analysis among 50,991 study participants from the China Pulmonary Health study. Multivariable linear regression models were used to obtain differences of forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), FEV1/FVC, peak expiratory flow (PEF), and forced expiratory flow at 25-75% of exhaled FVC (FEF25-75%) associated with an interquartile range (IQR) change of PM2.5 or its constituents. Residential annual PM2.5 levels varied from 26 µg/m3 to 92 µg/m3 (average: 53 µg/m3). An IQR increase of PM2.5 concentrations was associated with lower FEV1 (19.82 mL, 95% CI: 11.30-28.33), FVC (17.45 mL, 95% CI: 7.16-27.74), PEF (86.64 mL/s, 95% CI: 59.77-113.52), and FEF25-75% (31.93 mL/s, 95% CI: 16.64-47.22). Black carbon, organic matter, ammonium, sulfate, and nitrate were negatively associated with most lung function indicators, with organic matter and nitrate showing consistently larger magnitude of associations than PM2.5 mass. This large-scale study provides first-hand epidemiological evidence that long-term exposure to ambient PM2.5 and some constituents, especially organic matter and nitrate, were associated with lower large- and small- airway function.

MRI features of and factors related to ankle injuries in asymptomatic amateur marathon runners.

OBJECTIVE: To analyze the MRI manifestations of and factors related to ankle injuries in asymptomatic amateur marathon runners. MATERIALS AND METHODS: A total of 113 amateur marathon runners without any ankle joint symptoms were recruited. Each participant was asked to complete a questionnaire at the beginning of the study and underwent MRI of the ankle. The MRI manifestations of ankle injuries were summarized, and binary logistic regression analysis was applied to analyze the factors related to ankle injuries. RESULTS: The main MRI features were bone marrow edema-like signal intensity, peritendinous effusion, and partial lateral collateral ligament injury. Others included Achilles tendinopathy, cyst-like lesions, osteochondral lesions, and subcutaneous soft tissue edema. The risk factor for bone marrow edema-like signal intensity in amateur marathon runners was a rearfoot strike pattern (p = 0.028, OR = 1.172); the risk factors for peritendinous effusion were a higher weekly running distance (p = 0.013, OR = 1.685) and increased running years (p = 0.039, OR = 1.113), whereas a rearfoot strike pattern (p = 0.005, OR = 0.831) was a protective factor for peritendinous effusion; the risk factor for Achilles tendinopathy was increased age (p = 0.008, OR = 1.412); the risk factors for anterior talofibular ligament injury were a rearfoot strike pattern (p = 0.017, OR = 1.346) and higher weekly running distance (p = 0.022, OR = 1.171); and the factors for calcaneofibular ligament injury were a higher weekly running distance (p = 0.029, OR = 1.570) and rearfoot strike pattern (p = 0.035, OR = 1.463). CONCLUSION: The main MRI features of asymptomatic amateur marathon runners are bone marrow edema-like signal intensity, peritendinous effusion, and partial lateral collateral ligament injury. In addition, increased age, increased running years, higher weekly running distance, and different foot strike patterns are risk factors for ankle injuries.

Current situation of asthma-COPD overlap in Chinese patients older than 40 years with airflow limitation: a multicenter, cross-sectional, non-interventional study.

BACKGROUND AND AIMS: Asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) is poorly recognized in China. Our study determined the distribution of ACO and its clinical characteristics among patients (aged ⩾40 years) with airflow limitation at Chinese tertiary hospitals. METHODS: This cross-sectional, non-interventional study (NCT02600221), conducted between December 2015 and October 2016 in 20 Tier-3 Chinese hospitals, included patients aged ⩾40 years with post-bronchodilator (BD) FEV1/FVC <0.7. The primary variable was distribution of ACO in adults with post-BD forced expiratory volume /forced vital capacity (FEV1/FVC) <0.7 based on Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2015 and 2017 reports. Other variables included determination of characteristics of ACO and its clinical recognition rate. RESULTS: In 2003 patients (mean age 62.30 ± 9.86 years), distribution of ACO, COPD and asthma were 37.40%, 48.50% and 14.10%, respectively. Proportions of patients with A, B, C and D grouping were 11.70%, 31.00%, 6.90% and 50.30% as per GOLD 2017, whereas they were 15.10%, 51.10%, 3.60% and 30.20% as per GOLD 2015. Similar clinical symptoms were reported in all three groups. A higher percentage of ACO patients presented with dyspnea, wheezing and chest tightness. Compared with the COPD group, a greater proportion of ACO patients reported wheezing (74.6% and 65.40%), while a lower proportion in the ACO group reported cough (79.40% versus 82.70%) and expectoration (76.50% versus 81.60%). Blood eosinophil count ⩾0.3 × 109/L was observed in 34.6% of ACO patients. The clinical recognition rate of ACO was 31.4%. CONCLUSION: Despite ACO affecting two-fifths of the study population, the initial diagnosis rate was low at 6% in China, thus warranting concerted efforts to improve ACO diagnosis. CLINICALTRIALS.GOV: [ClinicalTrials.gov identifier: NCT02600221] registered 22 October 2015, https://clinicaltrials.gov/ct2/show/NCT02600221The reviews of this paper are available via the supplemental material section.

Comparison of the Clinical Outcomes Between Nebulized and Systemic Corticosteroids in the Treatment of Acute Exacerbation of COPD in China (CONTAIN Study): A Post Hoc Analysis.

Background and Objective: Although corticosteroids have been widely used in the treatment of acute exacerbation of chronic obstructive pulmonary disease (AECOPD), few studies have evaluated the effectiveness of nebulized corticosteroids (NCS), systemic corticosteroids (SCS), and NCS plus SCS in the management of AECOPD in China. This study aimed to evaluate the effectiveness of NCS, SCS, and NCS plus SCS in Chinese patients with AECOPD. Patients and Methods: This was a real-world study of AECOPD patients at 43 sites from January to September 2014. During hospitalization, patients treated with nebulized budesonide (NCS group, n=1091), SCS (SCS group, n=709), or both (NCS+SCS group, n=1846) were included. Propensity score matching (PSM) and subgroup analyses were performed. The primary outcomes were the length of hospital stay, mortality, and change in arterial blood gases from baseline. Results: Multivariable analysis showed that the three treatments at the same severity of AECOPD were not significantly different regarding intubation rates, rates of pneumonia improvement at discharge, rates of new-onset pneumonia in hospital, and mortality. Following PSM, NCS+SCS was associated with greater length of hospital stay than both NCS and SCS (in patients without respiratory failure [RF, P<0.001] and with type I RF [P=0.022]), and more hospitalization costs than the other two treatments (in patients without RF [P<0.001]). Conclusion: NCS is effective for patients with AECOPD, which may be an alternative treatment option. Further clinical trials are urgently needed to better understand the efficacy of NCS, SCS, and NCS+SCS in AECOPD management in China.

Prevalence and risk factors of small airway dysfunction, and association with smoking, in China: findings from a national cross-sectional study.

BACKGROUND: Small airway dysfunction is a common but neglected respiratory abnormality. Little is known about its prevalence, risk factors, and prognostic factors in China or anywhere else in the world. We aimed to estimate the prevalence of small airway dysfunction using spirometry before and after bronchodilation, both overall and in specific population subgroups; assess its association with a range of lifestyle and environmental factors (particularly smoking); and estimate the burden of small airway dysfunction in China. METHODS: From June, 2012, to May, 2015, the nationally representative China Pulmonary Health study invited 57 779 adults to participate using a multistage stratified sampling method from ten provinces (or equivalent), and 50 479 patients with valid lung function testing results were included in the analysis. We diagnosed small airway dysfunction on the basis of at least two of the following three indicators of lung function being less than 65% of predicted: maximal mid-expiratory flow, forced expiratory flow (FEF) 50%, and FEF 75%. Small airway dysfunction was further categorised into pre-small airway dysfunction (defined as having normal FEV1 and FEV1/forced vital capacity [FVC] ratio before bronchodilator inhalation), and post-small airway dysfunction (defined as having normal FEV1 and FEV1/FVC ratio both before and after bronchodilator inhalation). Logistic regression yielded adjusted odds ratios (ORs) for small airway dysfunction associated with smoking and other lifestyle and environmental factors. We further estimated the total number of cases of small airway dysfunction in China by applying present study findings to national census data. FINDINGS: Overall the prevalence of small airway dysfunction was 43·5% (95% CI 40·7-46·3), pre-small airway dysfunction was 25·5% (23·6-27·5), and post-small airway dysfunction was 11·3% (10·3-12·5). After multifactor regression analysis, the risk of small airway dysfunction was significantly associated with age, gender, urbanisation, education level, cigarette smoking, passive smoking, biomass use, exposure to high particulate matter with a diameter less than 2·5 µm (PM2·5) concentrations, history of chronic cough during childhood, history of childhood pneumonia or bronchitis, parental history of respiratory diseases, and increase of body-mass index (BMI) by 5 kg/m2. The ORs for small airway dysfunction and pre-small airway dysfunction were similar, whereas larger effect sizes were generally seen for post-small airway dysfunction than for either small airway dysfunction or pre-small airway dysfunction. For post-small airway dysfunction, cigarette smoking, exposure to PM2·5, and increase of BMI by 5 kg/m2 were significantly associated with increased risk, among preventable risk factors. There was also a dose-response association between cigarette smoking and post-small airway dysfunction among men, but not among women. We estimate that, in 2015, 426 (95% CI 411-468) million adults had small airway dysfunction, 253 (238-278) million had pre-small airway dysfunction, and 111 (104-126) million had post-small airway dysfunction in China. INTERPRETATION: In China, spirometry-defined small airway dysfunction is highly prevalent, with cigarette smoking being a major modifiable risk factor, along with PM2·5 exposure and increase of BMI by 5 kg/m2. Our findings emphasise the urgent need to develop and implement effective primary and secondary prevention strategies to reduce the burden of this condition in the general population. FUNDING: Ministry of Science and Technology of China; National Natural Science Foundation of China; National Health Commission of China.

REALizing and improving management of stable COPD in China: a multi-center, prospective, observational study to realize the current situation of COPD patients in China (REAL) - rationale, study design, and protocol.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is the fifth leading cause of death in China with a reported prevalence of 8.2% people aged ≥40 years. It is recommended that Chinese physicians follow Global Initiative for Chronic Obstructive Lung Disease (GOLD) and national guidelines, yet many patients with COPD in China remain undiagnosed. Furthermore, missed diagnoses and a lack of standardized diagnosis and treatment remain significant problems. The situation is further complicated by a lack of large-scale, long-term, prospective studies of real-world outcomes, including exacerbation rates, disease severity, efficacy of treatment, and compliance of COPD patients in China. METHODS/DESIGN: The REALizing and improving management of stable COPD in China (REAL) study is a 52-week multi-center, prospective, observational trial. REAL aims to recruit approximately 5000 outpatients aged ≥40 years with a clinical diagnosis of COPD per GOLD 2016. Outpatients will be consecutively recruited from approximately 50 tertiary and secondary hospitals randomly selected across six geographic regions to provide a representative population. Patients will receive conventional medical care as determined by their treating physicians. The primary objective is to evaluate COPD patient outcomes including lung function, health status, exacerbations, hospitalization rate, and dyspnea following 1 year of current clinical practice. Secondary objectives are to assess disease severity, treatment patterns, adherence to medication, and associated risk factors. Data will be collected at two study visits, at patients' usual care visits, and by telephone interview every 3 months. DISCUSSION: Knowledge of COPD among physicians in China is poor. The REAL study will provide reliable information on COPD management, outcomes, and risk factors that may help improve the standard of care in China. Patient recruitment began on 30 June 2017 and the estimated primary completion date is 30 July 2019. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT03131362. Registered on 20 March 2017.

Clinical Outcomes Of Using Nebulized Budesonide As The Initial Treatment For Acute Exacerbations Of Chronic Obstructive Pulmonary Disease: A Post-Hoc Analysis.

Purpose: The current guidelines recommend the use of systemic corticosteroids (SCS) as the optimal treatment for acute exacerbations of chronic obstructive pulmonary disease (AECOPD). The aim of this real-world study was to evaluate whether nebulized budesonide (NBS) could also be used as an initial treatment for AECOPD. Patients and methods: AECOPD patients initially treated with NBS or SCS (oral/intravenous) were enrolled. A large-scale, long-term multicenter cohort study of AECOPD patients was performed to analyze outcomes for each treatment (NCT02051166). Results: Initial NBS and SCS treatment resulted in similar outcomes in terms of improvements in FEV1, PaO2, SaO2, and PaCO2. Disease severity affected outcome similarly in both groups. When the groups were stratified according to whether the initial treatment was subsequently intensified or reduced, more intubation was seen in the groups in which initial treatment was intensified. NBS escalation and SCS reduction groups spent more days in the hospital. The NBS escalation group was associated with the highest medical expenditure and a relatively higher rate of new-onset pneumonia. The NBS maintenance/reduction group showed the lowest mortality rate between groups. Stratification according to initial PaCO2 level showed more intubation in the groups with high initial PaCO2 concentrations. Conclusion: These results indicate that NBS may be used as an initial treatment in certain AECOPD patients, and further studies are needed to better define those most likely to benefit.

Comparative analysis of medical expenditure with nebulized budesonide versus systemic corticosteroids in hospitalized patients with acute exacerbations of chronic obstructive pulmonary disease in China.

Purpose: Chronic obstructive pulmonary disease (COPD) is characterized by persistent respiratory symptoms and is a leading cause of disability in China. Acute exacerbations of COPD (AECOPD) are a leading cause of hospitalizations, and account for a substantial proportion of medical expenditure. Corticosteroids are commonly used to manage AECOPD in hospitalized patients, so our objective was to analyze the total medical expenditure associated with nebulized budesonide (nBUD) vs. systemic corticosteroids (SCS) in this population. Patients and methods: A post-hoc analysis was carried out in 1,577 and 973 patients diagnosed with COPD who had received "any" nBUD or SCS regimen for AECOPD during hospitalization, respectively. Regimens included monotherapy, sequential therapy, and sequential-combination therapy. Comparative total medical expenditure was analyzed using a generalized linear model controlling for age, gender, comorbidities, smoking history, and respiratory failure or pneumonia on admission. Results: The total medical expenditure per capita with any nBUD or SCS regimen was CN¥11,814 (US$1,922) and CN¥12,153 (US$1,977), respectively. Any nBUD regimen was associated with a significant saving of 5.1% in expenditure compared with any SCS regimen (P=0.0341). Comorbidities, Type II respiratory failure, or pneumonia were patient factors associated with higher total medical expenditure (P<0.0001). In a subgroup analysis of the patients who received monotherapy, total medical expenditure was CN¥10,900 (US$1,773) for nBUD and CN¥11,581 (US$1,884) for SCS; nBUD was associated with a significant saving of 8.7% in expenditure compared with SCS (P=0.0013). Similarly, in patients with respiratory failure, treatment with any nBUD regimen was associated with a 10.6% saving in expenditure over any SCS regimen (P=0.0239); however, the same comparison was not significant in patients without respiratory failure (3.4%; P=0.2299). Conclusion: AECOPD is a leading cause of hospitalization in China, which places substantial burden on the healthcare system. This post-hoc analysis suggests that nBUD regimens are associated with lower medical expenditure than SCS regimens in hospitalized patients with AECOPD, and may reduce the financial burden of COPD. However, prospective studies evaluating the effectiveness of nBUD therapies are warranted.

Prevalence, risk factors, and management of asthma in China: a national cross-sectional study.

BACKGROUND: Asthma is a common chronic airway disease worldwide. Despite its large population size, China has had no comprehensive study of the national prevalence, risk factors, and management of asthma. We therefore aimed to estimate the national prevalence of asthma in a representative sample of the Chinese population. METHODS: A representative sample of 57 779 adults aged 20 years or older was recruited for the national cross-sectional China Pulmonary Health (CPH) study using a multi-stage stratified sampling method with parameters derived from the 2010 census. Ten Chinese provinces, representative of all socioeconomic settings, from six geographical regions were selected, and all assessments were done in local health centres. Exclusion criteria were temporary residence, inability to take a spirometry test, hospital treatment of cardiovascular conditions or tuberculosis, and pregnancy and breastfeeding. Asthma was determined on the basis of a self-reported history of diagnosis by a physician or by wheezing symptoms in the preceding 12 months. All participants were assessed with a standard asthma questionnaire and were classed as having or not having airflow limitation through pulmonary function tests before and after the use of a bronchodilator (400 µg of salbutamol). Risk factors for asthma were examined by multivariable-adjusted analyses done in all participants for whom data on the variables of interest were available. Disease management was assessed by the self-reported history of physician diagnosis, treatments, and hospital visits in people with asthma. FINDINGS: Between June 22, 2012, and May 25, 2015, 57 779 participants were recruited into the CPH study. 50 991 (21 446 men and 29 545 women) completed the questionnaire survey and had reliable post-bronchodilator pulmonary function test results and were thus included in the final analysis. The overall prevalence of asthma in our sample was 4·2% (95% CI 3·1-5·6), representing 45·7 million Chinese adults. The prevalence of asthma with airflow limitation was 1·1% (0·9-1·4), representing 13·1 million adults. Cigarette smoking (odds ratio [OR] 1·89, 95% CI 1·26-2·84; p=0·004), allergic rhinitis (3·06, 2·26-4·15; p<0·0001), childhood pneumonia or bronchitis (2·43, 1·44-4·10; p=0·002), parental history of respiratory disease (1·44, 1·02-2·04; p=0·040), and low education attainment (p=0·045) were associated with prevalent asthma. In 2032 people with asthma, only 28·8% (95% CI 19·7-40·0) reported ever being diagnosed by a physician, 23·4% (13·9-36·6) had a previous pulmonary function test, and 5·6% (3·1-9·9) had been treated with inhaled corticosteroids. Furthermore, 15·5% (11·4-20·8) people with asthma reported at least one emergency room visit and 7·2% (4·9-10·5) at least one hospital admission due to exacerbation of respiratory symptoms within the preceding year. INTERPRETATION: Asthma is prevalent but largely undiagnosed and undertreated in China. It is crucial to increase the awareness of asthma and disseminate standardised treatment in clinical settings to reduce the disease burden. FUNDING: National Key R&D Program of China, Ministry of Science and Technology of China; the Special Research Foundation for Public Welfare of Health, Ministry of Health of China; the Chinese National Research Program for Key Issues in Air Pollution Control; and the National Natural Science Foundation of China.

Gender difference on the knowledge, attitude, and practice of COPD diagnosis and treatment: a national, multicenter, cross-sectional survey in China.

PURPOSE: To investigate the gender difference in knowledge, attitude, and practice of COPD diagnosis and treatment in China. PATIENTS AND METHODS: A nationwide, multicenter, cross-sectional questionnaire study was carried out to investigate patients' understanding and experience of COPD between September 2007 and December 2008. RESULTS: Two thousand and seventy-two patients were recruited from eleven centers. The final effective questionnaires were those of 1,698 cases, of which 32% were female. Women were younger, had higher body mass index, were more never smokers, and had lesser pack-years (all P<0.01). More women had under elementary education level and monthly income <1,000 RMB (about 160 USD) (all P<0.01). Women had higher ratio of FEV1/FVC (54.1±10.9 vs 50.2±11.5), FEV1% (50.0±19.1 vs 45.4±29.0), and lower short form-36 mental component summary (57.5±26.8 vs 61.3±25.0) (all P<0.01). Fewer women reported severe exacerbation (defined as an acute worsening of respiratory symptoms that results in patient's hospitalization) in the previous year (44.5% vs 51.6%, P<0.05). More women reported that they never heard of COPD before (67.0% vs 59.0%, P<0.01). Less women reported that physician had to tell them they had emphysema (50.5% vs 60.4%) or COPD (31.9% vs 37.9%). Less women had pulmonary function test (PFT) done before (65.2% vs 70.4%, P<0.05). More women reported that they would not repeat PFT annually (91.7% vs 87.6%, P<0.05) and did not know the PFT results (78.6% vs 73.1%, P<0.05). More women reported not having had pulmonary rehabilitation before (87.8% vs 83.6%, P<0.05). Fewer women reported knowing that COPD should be given combined therapy (38.3% vs 44.5%) and long-term treatment (46.1% vs 51.9%) (all P<0.05). CONCLUSION: Male and female patients had different experiences on COPD diagnosis and treatment. Physicians should pay more attention to patients' education on COPD, especially of women.

Prevalence and risk factors of chronic obstructive pulmonary disease in China (the China Pulmonary Health [CPH] study): a national cross-sectional study.

BACKGROUND: Although exposure to cigarette smoking and air pollution is common, the current prevalence of chronic obstructive pulmonary disease (COPD) is unknown in the Chinese adult population. We conducted the China Pulmonary Health (CPH) study to assess the prevalence and risk factors of COPD in China. METHODS: The CPH study is a cross-sectional study in a nationally representative sample of adults aged 20 years or older from ten provinces, autonomous regions, and municipalities in mainland China. All participants underwent a post-bronchodilator pulmonary function test. COPD was diagnosed according to 2017 Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria. FINDINGS: Between June, 2012, and May, 2015, 57 779 individuals were invited to participate, of whom 50 991 (21 446 men and 29 545 women) had reliable post-bronchodilator results and were included in the final analysis. The overall prevalence of spirometry-defined COPD was 8·6% (95% CI 7·5-9·9), accounting for 99·9 (95% CI 76·3-135·7) million people with COPD in China. Prevalence was higher in men (11·9%, 95% CI 10·2-13·8) than in women (5·4%, 4·6-6·2; p<0·0001 for sex difference) and in people aged 40 years or older (13·7%, 12·1-15·5) than in those aged 20-39 years (2·1%, 1·4-3·2; p<0·0001 for age difference). Only 12·0% (95% CI 8·1-17·4) of people with COPD reported a previous pulmonary function test. Risk factors for COPD included smoking exposure of 20 pack-years or more (odds ratio [OR] 1·95, 95% CI 1·53-2·47), exposure to annual mean particulate matter with a diameter less than 2·5 µm of 50-74 µg/m3 (1·85, 1·23-2·77) or 75 µg/m3 or higher (2·00, 1·36-2·92), underweight (body-mass index <18·5 kg/m2; 1·43, 1·03-1·97), sometimes childhood chronic cough (1·48, 1·14-1·93) or frequent cough (2·57, 2·01-3·29), and parental history of respiratory diseases (1·40, 1·23-1·60). A lower risk of COPD was associated with middle or high school education (OR 0·76, 95% CI 0·64-0·90) and college or higher education (0·47, 0·33-0·66). INTERPRETATION: Spirometry-defined COPD is highly prevalent in the Chinese adult population. Cigarette smoking, ambient air pollution, underweight, childhood chronic cough, parental history of respiratory diseases, and low education are major risk factors for COPD. Prevention and early detection of COPD using spirometry should be a public health priority in China to reduce COPD-related morbidity and mortality. FUNDING: Ministry of Health and Ministry of Science and Technology of China.