Prevalence of chronic obstructive pulmonary disease in China: a large, population-based survey

An investigation of the risk factors of chronic obstructive pulmonary disease in natural population-based cohorts in China - a nested case-control study

Background

Chronic obstructive pulmonary disease (COPD) has become one of the most significant chronic diseases in China. According to conventional wisdom, smoking is the pathogenic factor. However, current research indicates that the pathophysiology of COPD may be associated with prior respiratory system events (e.g., childhood hospitalization for pneumonia, chronic bronchitis) and environmental exposure (e.g., dust from workplace, indoor combustion particles). Dyspnea, persistent wheezing, and other respiratory symptoms further point to the need for pulmonary function tests in this population. Reducing the burden of chronic diseases in China requires a thorough understanding of the various factors that influence the occurrence of COPD.

Methods

Using a cohort from the natural population, this study used nested case-control analysis. We carried out a number of researches, including questionnaire surveys and pulmonary function testing, in the Northwest and Southeast cohorts of China between 2014 and 2021. After removing any variations in the baseline data between patients and control subjects using propensity score matching analysis, the risk factors were examined using univariate or multivariate regression.

Result

It was discovered that prior history of chronic bronchitis, long-term wheezing symptoms, and environmental exposure-including smoking and biofuel combustion-were risk factors for COPD. Dyspnea, symptoms of mobility limitation, organic matter, and a history of hospitalization for pneumonia at an early age were not significant in the clinical model but their incidence in COPD group is higher than that in healthy population.

Discussion

COPD screening effectiveness can be increased by looking for individuals with chronic respiratory symptoms. Smokers should give up as soon as they can, and families that have been exposed to biofuels for a long time should convert to clean energy or upgrade their ventilation. Individuals who have previously been diagnosed with emphysema and chronic bronchitis ought to be extra mindful of the prevention or advancement of COPD.

Characteristics of inflammatory phenotypes in patients with chronic obstructive pulmonary disease: a cross-sectional study

BACKGROUND

The relationship between airway inflammation in chronic obstructive pulmonary disease (COPD) and clinical characteristics remains unclear. This study aimed to investigate the airway inflammatory phenotypes in COPD and their association with clinical characteristics.

METHODS

895 patients with COPD were recruited from Guangdong Province, China in this study. Each patient underwent questionnaire interviews, spirometry testing, CT scans and induced sputum examination. Classification of airway inflammation phenotypes was based on sputum inflammatory cell counts. Covariance analysis was applied to assess associations with airway inflammation phenotypes.

RESULTS

In this study, we found that neutrophilic phenotype (NP, 58.0%) was the most common airway inflammation phenotype in patients with COPD, followed by mixed granulocytic phenotype (MGP, 32.6%), eosinophilic phenotype (EP, 5.4%) and paucigranulocytic phenotype (PP, 4.0%). Compared with NP patients, those with MGP exhibited more frequent chronic respiratory symptoms, and a higher proportion of individuals classified under Global Initiative for Chronic Obstructive Lung Disease stages 3 and 4. After adjusting for confounding factors, MGP patients had lower lung function, and more severe emphysema and air trapping. On the contrary, patients with PP had the best pulmonary function and less emphysema and air trapping.

CONCLUSIONS

NP was the most common airway inflammation phenotype in patients with COPD. Patients with MGP had more respiratory symptoms, greater loss of lung function, and more severe emphysema and gas trapping compared with those with NP. Meanwhile, PP may be a phenotype of mild damage to lung structure in patients with COPD.

An explainable artificial intelligence framework for risk prediction of COPD in smokers

BACKGROUND

Since the inconspicuous nature of early signs associated with Chronic Obstructive Pulmonary Disease (COPD), individuals often remain unidentified, leading to suboptimal opportunities for timely prevention and treatment. The purpose of this study was to create an explainable artificial intelligence framework combining data preprocessing methods, machine learning methods, and model interpretability methods to identify people at high risk of COPD in the smoking population and to provide a reasonable interpretation of model predictions.

METHODS

The data comprised questionnaire information, physical examination data and results of pulmonary function tests before and after bronchodilatation. First, the factorial analysis for mixed data (FAMD), Boruta and NRSBoundary-SMOTE resampling methods were used to solve the missing data, high dimensionality and category imbalance problems. Then, seven classification models (CatBoost, NGBoost, XGBoost, LightGBM, random forest, SVM and logistic regression) were applied to model the risk level, and the best machine learning (ML) model's decisions were explained using the Shapley additive explanations (SHAP) method and partial dependence plot (PDP).

RESULTS

In the smoking population, age and 14 other variables were significant factors for predicting COPD. The CatBoost, random forest, and logistic regression models performed reasonably well in unbalanced datasets. CatBoost with NRSBoundary-SMOTE had the best classification performance in balanced datasets when composite indicators (the AUC, F1-score, and G-mean) were used as model comparison criteria. Age, COPD Assessment Test (CAT) score, gross annual income, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), anhelation, respiratory disease, central obesity, use of polluting fuel for household heating, region, use of polluting fuel for household cooking, and wheezing were important factors for predicting COPD in the smoking population.

CONCLUSION

This study combined feature screening methods, unbalanced data processing methods, and advanced machine learning methods to enable early identification of COPD risk groups in the smoking population. COPD risk factors in the smoking population were identified using SHAP and PDP, with the goal of providing theoretical support for targeted screening strategies and smoking population self-management strategies.

A nested case-control study of the effects of dust exposure, smoking on COPD in coal workers

BACKGROUND

Chronic obstructive pulmonary disease (COPD) represents a prevalent ailment, progressively surging within the ranks of coal mine laborers. The current study endeavors to elucidate the effects of dust exposure and smoking on COPD incidence amongst coal mine workers, while concurrently devising preventive strategies for this affliction.

METHOD

A nested case-control study was conducted encompassing 1,416 participants aged ≥ 18 years, spanning the duration from (2017-2018) until 2020. A meticulous matching process yielded a cohort of 708 COPD patients, each paired with a control subject, forming a harmonious 1:1 ratio. Multiple logistic regression analysis was employed to scrutinize the associations between smoking, dust exposure with COPD among coal workers.

RESULTS

The COPD prevalence within the cohort of coal workers under investigation amounted to 22.66%, with an accompanying incidence density of 0.09/person-year. Following meticulous adjustment for confounding variables, it was discerned that cumulative dust exposure within the range of 47.19 ~ (OR: 1.90, 95% CI: 1.05, 3.44), 101.27 ~ (OR: 1.99, 95% CI: 1.17, 3.39), as well as smoking indices of 72 ~ (OR: 1.85, 95% CI: 1.19, 2.88), 145 ~ (OR: 1.74, 95% CI: 1.17, 2.61), 310 ~ (OR: 1.85, 95% CI: 1.23, 2.77) engender an escalated vulnerability to COPD among coal workers. Furthermore, interaction analysis discerned an absence of both multiplicative and additive interactions between dust exposure, smoking, and COPD occurrence amidst coal workers.

CONCLUSION

Dust exposure and smoking were unequivocally identified as precipitating risk factors for COPD incidence within the population of coal workers, albeit devoid of any discernible interaction between these two causal agents.

Association of Exposure to Biomass Fuels with Occurrence of Chronic Obstructive Pulmonary Disease in Rural Western China: A Real-World Nested Case-Control Study

Background

This study investigated the potential contribution of biomass fuels exposure to the occurrence of chronic obstructive pulmonary disease (COPD) in rural areas of western China.

Methods

We analyzed data collected between October 2017 and October 2018 from a nested case-control study of individuals at least 40 years old in the general population in Mianyang City, Sichuan Province, China. Demographic information was collected using a custom-designed questionnaire, and lung function was measured using spirometry. We used multivariate logistic regression to explore the possible relationship between biomass fuels exposure and COPD, as well as between other potential risk factors and COPD. Bayes' theorem was used to estimate weights for different COPD risk factors.

Results

COPD was newly diagnosed in 500 of the 11398 adults surveyed, corresponding to an incidence of 4.39%. Individuals who were exposed to biomass fuels were at a significantly greater risk of developing COPD than those not exposed (OR 2.58, 95% CI 2.23-3.05). In subgroup analysis, exposure to biomass fuels increased the risk of COPD in men by 1.71 times (95% CI 1.09-2.68) and in women by 2.88 times (95% CI 2.01-3.48), in never-smokers by 2.18 times. Bayesian weights for COPD risk factors were highest for poor kitchen ventilation (W=31.13%) and biomass fuels exposure (W=18.08%).

Conclusion

Our data indicate that rural Chinese who are exposed to biomass fuels during cooking or heating are at greater risk of developing COPD. Efforts should be made to strengthen the construction of clean energy infrastructure, so as to reduce the use of biomass fuels and thereby help prevent COPD.

Use of CAPTURE to Identify Individuals Who May or May Not Require Treatment for Chronic Obstructive Pulmonary Disease

Rationale: The CAPTURE tool (Chronic Obstructive Pulmonary Disease [COPD] Assessment in Primary Care to Identify Undiagnosed Respiratory Disease and Exacerbation Risk) was developed to identify patients with undiagnosed COPD with an FEV1 <60% predicted or risk of exacerbation as treatment criteria. Objectives: To test the ability of CAPTURE to identify patients requiring treatment because of symptoms or risk of exacerbation or hospitalization. Methods: Data were from COMPASS (Clinical, Radiological and Biological Factors Associated with Disease Progression, Phenotypes and Endotypes of COPD in China), a prospective study of COPD, chronic bronchitis without airflow limitation (postbronchodilator FEV1/FVC ratio ≥0.70), and healthy never-smokers. CAPTURE was tested as questions alone and with peak expiratory flow measurement. Sensitivity, specificity, and positive and negative predicted values (PPV and NPV) were calculated for COPD Assessment Test (CAT) scores ⩾10 versus <10, modified Medical Research Council (mMRC) scores ⩾2 versus <2, and at least one moderate exacerbation or hospitalization in the previous year versus none. Measurements and Main Results: Patients with COPD (n = 1,696) had a mean age of 65 ± 7.5 years, and 90% were male, with a postbronchodilator FEV1 of 66.5 ± 20.1% predicted. Control participants (n = 307) had a mean age of 60.2 ± 7.0 years, and 65% were male, with an FEV1/FVC ratio of 0.78 ± 0.04. CAPTURE using peak expiratory flow showed the best combination of sensitivity and specificity. Sensitivity and specificity were 68.5% and 64.0%, respectively, to detect a CAT score ⩾10; 85.6% and 61.0% to detect an mMRC score ⩾2; 63.5% and 55.6% to detect at least one moderate exacerbation; and 70.2% and 59.4% to detect at least one hospitalization. PPVs ranged from 15.6% (moderate exacerbations) to 47.8% (CAT score). NPVs ranged from 80.8% (CAT score) to 95.6% (mMRC score). Conclusions: CAPTURE has good sensitivity to identify patients with COPD who may require treatment because of increased symptoms or risk of exacerbations or hospitalization, including those with an FEV1 >60% predicted. High NPV values show that CAPTURE can also exclude those who may not require treatment. Clinical trial registered with www.clinicaltrials.gov (NCT04853225).

The gut microbiome as a potential source of non-invasive biomarkers of chronic obstructive pulmonary disease

BACKGROUND

The link between gut microbial dysbiosis and the development of chronic obstructive pulmonary disease (COPD) is of considerable interest. However, little is known regarding the potential for the use of the fecal metagenome for the diagnosis of COPD.

METHODS

A total of 80 healthy controls, 31 patients with COPD severity stages I or II, and 49 patients with COPD severity stages III or IV fecal samples were subjected to metagenomic analysis. We characterized the gut microbiome, identified microbial taxonomic and functional markers, and constructed a COPD disease classifier using samples.

RESULTS

The fecal microbial diversity of patients with COPD stages I or II was higher than that of healthy controls, but lower in patients with COPD stages III or IV. Twenty-one, twenty-four, and eleven microbial species, including potential pathogens and pro-inflammatory bacteria, were significantly enriched or depleted in healthy controls, patients with COPD stages I or II, and patients with COPD stages III & IV. The KEGG orthology (KO) gene profiles derived demonstrated notable differences in gut microbial function among the three groups. Moreover, gut microbial taxonomic and functional markers could be used to differentiate patients with COPD from healthy controls, on the basis of areas under receiver operating characteristic curves (AUCs) of 0.8814 and 0.8479, respectively. Notably, the gut microbial taxonomic features differed between healthy individuals and patients in stages I-II COPD, which suggests the utility of fecal metagenomic biomarkers for the diagnosis of COPD (AUC = 0.9207).

CONCLUSION

Gut microbiota-targeted biomarkers represent potential non-invasive tools for the diagnosis of COPD.

Prevalence, risk factors, and mortality of COPD in young people in the USA: results from a population-based retrospective cohort

BACKGROUND

Chronic obstructive pulmonary disease (COPD) has been considered a disease of the elderly, but it could also occur in young people aged 20-50 years. However, the characteristics and prognosis of COPD in such young people remain unclear.

METHODS

Our retrospective cohort study was based on the National Health and Nutrition Examination Survey (NHANES). Participants who 20-50 years old at baseline and completed the pulmonary function test were enrolled in our study cohort. These participants were followed up to 31 December 2019. The sample weight and Taylor Linearization Procedures were adapted to make representative estimations of prevalence and baseline characteristics. The weighted logistic regression model was used to assess the risk factors. The propensity score method and Cox proportional hazard models were applied to calculate the risk of mortality.

RESULTS

The weighted prevalence of COPD in young people in the USA was 1.64% and it increased with age, with a higher prevalence in males than females (2.59% vs 0.72%, p<0.001). The proportion of Global Initiative for COPD 1-2 was 96.7%. Males (OR=4.56, 95% CI: 2.74 to 7.61), non-Hispanic black (OR=2.77; 95% CI: 1.14 to 6.75), non-Hispanic white (OR=4.93; 95% CI: 2.16 to 11.28) and smoking (current smoking, OR=2.36; 95% CI: 1.40 to 3.98; ever smoking, OR=1.92; 95% CI: 1.05 to 3.51; passive smoking, OR=2.12; 95% CI: 1.41 to 3.20) were shown to be independent risk factors for COPD in young people. Compared with those matched by sex, age and race, the young people with COPD had a higher risk of all-cause death (HR=3.314, p<0.001).

CONCLUSION

COPD in young people has a low prevalence in the USA and its independent risk factors included male, race (non-Hispanic black and non-Hispanic white) and smoking. Young COPD has a higher risk of all-cause mortality than the matched non-COPD.

The influence of pyroptosis-related genes on the development of chronic obstructive pulmonary disease

Increasing evidences have demonstrated that pyroptosis exerts key roles in the occurrence, development of chronic obstructive pulmonary disease. However, the mechanisms of pyroptosis in COPD remain largely unknown. In our research, Statistics were performed using R software and related packages in this study. Series matrix files of small airway epithelium samples were downloaded from the GEO database. Differential expression analysis with FDR < 0.05 was performed to identify COPD-associated pyroptosis-related genes. 8 up-regulated genes (CASP4, CASP5, CHMP7, GZMB, IL1B, AIM2, CASP6, GSDMC) and 1 down-regulated genes (PLCG1) was identified as COPD-associated pyroptosis-related genes. Twenty-six COPD key genes was identified by WGCNA analysis. PPI analysis and gene correlation analysis showed their relationship clearly. KEGG and GO analysis have revealed the main pyroptosis-related mechanism of COPD. The expression of 9 COPD-associated pyroptosis-related genes in different grades was also depicted. The immune environment of COPD was also explored. Furthermore, the relationship of pyroptosis-related genes and the expression of immune cells was also be shown in the end. In the end, we concluded that pyroptosis influences the development of COPD. This study may provide new insight into the novel therapeutic targets for COPD clinical treatment.

Investigation and Analysis of Risk Factors and Psychological Status of Chronic Obstructive Pulmonary Disease in Permanent Residents Aged 40 or Older in Hongyuan County, Aba Prefecture, Sichuan Province

Background

COPD is an important public health problem worldwide, and there is a lack of epidemiological data on COPD in high-altitude areas in Sichuan province. Thus, we aimed to investigate the prevalence, risk factors and psychological status of COPD in Hongyuan County, Aba Prefecture, Sichuan Province, which is located at an average altitude of 3507 meters.

Methods

The 40 years old or greater permanent residents of Hongyuan County were selected by random sampling method, and the lung function test and questionnaires were conducted to determine the disease situation of COPD. The prevalence of COPD was compared among different factors of investigation, and multivariate logistic regression analysis was used for different factors to determine the independent influencing factors of COPD disease.

Results

A total of 456 permanent residents aged 40 years or older in Hongyuan County, 436 qualified for quality control, among which 53 cases confirmed COPD, the total prevalence was 12.16%, among which the prevalence was 14.55% for men and it was 8.07% for women. There were significant differences in different gender, ethnicity, age, smoking status, smoking years, educational level, heating style, history of tuberculosis, and prevalence of BMI (P <0.05). Binary logistic regression analysis showed that age ≥60 years (OR = 2.810, 95% CI: 1.0457.557), Han Nationality (OR: 3.238, 95% CI: 1.290-8.127), the heating method including biofuels (OR: 18.119, 95% CI: 4.140-79.303) and coals (OR: 6.973, 95% CI: 1.856-26.200), medical history of pulmonary tuberculosis (OR: 2.670, 95% CI: 1.278-5.578), the education level including junior high school (OR: 3.336, 95% CI: 1.2259.075), high school and above (OR: 5.910, 95% CI: 1.796-19.450), and smoking (OR: 10.774, 95% CI: 3.622-32.051) were independent risk factors for COPD disease. The prevalence of anxiety was 16.98%, and the prevalence of depression was 13.2%.

Conclusion

The prevalence of COPD in Hongyuan County was higher than the national level; age, ethnic group, education, smoking, heating method, and history of tuberculosis are the independent influencing factors of COPD in Hongyuan County. The prevalence of anxiety and depression is low.

Effect of nitric oxide synthase gene polymorphism on inflammatory response in patients with chronic obstructive pulmonary disease

This study aimed to investigate the association between nitric oxide synthase gene polymorphisms and the inflammatory responses in patients with 'fast-' and 'slow-' developing chronic obstructive pulmonary disease (COPD). In the main process, 190 patients with slow-developing COPD, 94 patients with fast-developing COPD and 105 healthy volunteers were selected for inclusion. Endothelial nitric oxide synthase (eNOS) was detected using western-blot eNOS sites, and inducible nitric oxide synthase (iNOS) was detected through SNPshot. T helper 17 cells (Th17) and regulator T (Treg) cells were detected via flow cytometry, and interferon-gamma, tumour necrosis factor-alpha, interleukin (IL)-17, IL-10, IL-6, IL-4 and IL-2 were detected using a cytometric bead array. The final results and conclusions drawn from the tests suggest that Th17/Treg-mediated immune inflammation plays an important role in the pathogenesis of COPD, but whether it affects the development of COPD needs further investigation. Overall, COPD patients with a young age of onset, young age of smoking initiation and small body mass index, as well as COPD patients with CC at rs3729508 in the iNOS gene and non-GG at rs7830 in the eNOS gene, may be more likely to contract fast-developing COPD.

Efficacy of acupuncture therapy for stable chronic obstructive pulmonary disease: A systematic review and meta-analysis

BACKGROUND

Acupuncture therapy (AT) is a widely used, alternative medicine in China. AT is an effective treatment for many diseases, but its efficacy in stable chronic obstructive pulmonary disease (COPD) remains controversial. Therefore, we performed the present meta-analysis to evaluate the efficacy of AT in stable COPD patients.

METHODS

Randomized controlled trials (RCTs) for AT efficacy in stable COPD patients were searched in literature databases from the inception to December 31, 2021. Pooled effect sizes of outcome measurements with respect to lung function (forced vital capacity [FVC], forced expiratory volume in 1 second [FEV1], FEV1 in predicted value [FEV1%], FEV1/FVC), quality of life (St. George respiratory questionnaire [SGRQ]), exercise capacity (6-minute walking distance [6MWD]) and effective rate were estimated by calculating weighted mean difference (WMD) or odds ratio (OR) with corresponding 95% confidence interval (95% CI), respectively, by a random-effect model.

RESULTS

A total of 28 RCTs with 2130 COPD patients were included. AT group had significant improvement in FVC (WMD = 0.29 L, 95% CI: 0.22-0.36, P < .001), FEV1 (WMD = 0.33 L, 95% CI: 0.23-0.43, P < .001), FEV1% (WMD = 3.30%, 95% CI: 3.30-4.64, P < .001), FEV1/FVC (WMD = 5.45%, 95% CI: 4.41-6.49, P < .001), 6MWD (WMD = 45.48 m, 95% CI: 28.21-62.16, P < .001), SGRQ (WMD = -7.79, 95% CI: -12.34 to -3.24, P < .001), and a higher effective rate (OR = 3.71, 95% CI: 2.50-5.52, P < .001) compared to the control group. Subgroup analysis stratified by comparison model (AT combined with other treatments vs other treatments, AT alone vs sham AT) and treatment duration (≥8 weeks, <8 weeks) also showed more improvement in AT arm than control arm without significant between-subgroup difference. Adverse events were reported in a few studies and only mild reactions were observed.

CONCLUSION

AT is effective in improving lung function, quality of life and exercise capacity, and can be used as an adjunctive treatment in patients with stable COPD.

Prevalence and Risk Factors for COPD in an Urbanizing Rural Area in Western China: A Cross-Sectional Study

Purpose

To investigate the prevalence and risk factors for chronic obstructive pulmonary disease (COPD) in a rural area in western China with severe air pollution.

Patients and Methods

10% of local residents aged 40 years and above were included using a convenience sampling method. This was a cross-sectional study. A self-designed questionnaire was used to collect participants' demographic data. The screening program was comprised of two steps: First, a portable electronic spirometer was used for COPD screening. Those participants with FEV1/FVC ratio <0.7 were then referred to a confirmatory pulmonary function (PF) test. COPD was confirmed according to the 2020 Global Initiative for Chronic Obstructive Lung Disease criteria.

Results

A total of 4577 participants aged 40 years old or above were included in the final analysis. Examination with a mobile spirometer identified 1159 individuals for confirmatory testing; after that, of the 1159 individuals, 889 were diagnosed with COPD by the confirmatory PF test. The prevalence of COPD among the target group was 19.4%. Older age, male sex (odds ratio [OR] = 1.537, 95% confidence interval [CI] 1.246-1.894), smoking history (OR = 1.338, 95% CI 1.069-1.675), family history of respiratory disease (OR = 1.625, 95% CI 1.350-1.957), education level (OR = 0.735, 95% CI 0.617-0.876), overweight (OR = 0.614, 95% CI 0.517-0.730) and obesity (OR = 0.572, 95% CI 0.449-0.721) were identified as independent factors associated with COPD. The screening program helped earlier detection of COPD in 719 participants.

Conclusion

COPD was highly prevalent in the rural area studied. Rural residents who were older, current or ever-smokers, male and those who had a lower education level were more vulnerable to developing COPD. The COPD screening program may be helpful for earlier disease detection in rural health-care settings.

Polycyclic aromatic hydrocarbon exposure burden: Individual and mixture analyses of associations with chronic obstructive pulmonary disease risk

Accumulating data demonstrate that polycyclic aromatic hydrocarbons (PAH) exposure is linked to compromised respiratory diseases. This study aimed to analyze urinary PAH metabolites and their associations with chronic obstructive pulmonary disease (COPD) in a sample size of 3015 subjects from a total population of 50,588 from the National Health and Nutrition Examination Survey (NHANES) in 2007-2016. Results showed that the most predominant metabolite was 1-Hydroxynaphthalene (1-NAP, 84%) with a geometric mean concentration of 50,265 ng/L, followed by its homologue 2-NAP (10%), both of which arose from sources including road emission, smoking and cooking. Multiple logistic regression showed that seven of the ten major PAH metabolites were correlated with increased COPD risk: including 1-NAP (OR: 1.83, 95%CI: 1.25, 2.69), 2-Hydroxyfluorene (2-FLU, OR: 2.29, 95%CI: 1.42, 3.68) and 1-Hydroxyphenanthrene (1-PHE, OR: 2.79, 95%CI: 1.85, 4.21), when compared to the lowest tertile after adjusted for covariates. Total exposure burden per PAH congener sub-group demonstrated persistent positive correlation with COPD for ∑PHE (OR: 1.80, 95%CI: 1.34, 2.43) and ∑FLU (OR: 2.74, 95%CI: 1.77, 4.23) after adjusted for covariates. To address the contribution of PAH exposure as mixture towards COPD, weighted quantile sum (WQS) regression analyses revealed that 1-NAP, 9-Hydroxyfluorene (9-FLU), 3-Hydroxyfluorene (3-FLU) and 1-PHE were among the top contributors in the associations with COPD. Our results demonstrate the contemporary yet ongoing exposure burden of PAH exposure for over a decade, particularly towards NAPs and FLUs that contribute significantly to COPD risk, calling for more timely environmental regulation.

Clinical features and 1-year outcomes of chronic bronchitis in participants with normal spirometry: results from the ECOPD study in China

BACKGROUND

Evidence regarding clinical features and outcomes of individuals with non-obstructive chronic bronchitis (NOCB) remains scarce, especially in never-smokers. We aimed to investigate the clinical features and 1-year outcomes of individuals with NOCB in the Chinese population.

METHODS

We obtained data on participants in the Early Chronic Obstructive Pulmonary Disease Study who had normal spirometry (post-bronchodilator forced expiratory volume in 1 s/forced vital capacity ≥0.70). NOCB was defined as chronic cough and sputum production for at least 3 months for two consecutive years or more at baseline in participants with normal spirometry. We assessed the differences in demographics, risk factors, lung function, impulse oscillometry, CT imaging and frequency of acute respiratory events between participants with and without NOCB.

RESULTS

NOCB was present in 13.1% (149/1140) of participants with normal spirometry at baseline. Compared with participants without NOCB, those with NOCB had a higher proportion of men and participants with smoke exposure, occupational exposure, family history of respiratory diseases and worse respiratory symptoms (all p<0.05), but there was no significant difference in lung function. Never-smokers with NOCB had higher rates of emphysema than those without NOCB, but airway resistance was similar. Ever-smokers with NOCB had greater airway resistance than those without NOCB, but emphysema rates were similar. During 1-year follow-up, participants with NOCB had a significantly increased risk of acute respiratory events compared with participants who did not have NOCB, after adjustment for confounders (risk ratio 2.10, 95% CI 1.32 to 3.33; p=0.002). These results were robust in never-smokers and ever-smokers.

CONCLUSIONS

Never-smokers and ever-smokers with NOCB had more chronic obstructive pulmonary disease-related risk factors, evidence of airway disease and greater risk of acute respiratory events than those without NOCB. Our findings support expanding the criteria defining pre-COPD to include NOCB.

The correlation between a Th1/Th2 cytokines imbalance and vitamin D level in patients with early chronic obstructive pulmonary disease (COPD), based on screening results

Objective: This study explored the correlation between a Th1/Th2 cytokines imbalance and 25-hydroxy-vitamin D (vit D) level in early chronic obstructive pulmonary disease (COPD), provided experimental rationales for the role of vit D in the prevention and control of COPD, and elucidated the potential anti-inflammatory mechanism involved.

Methods: This study was based on the results of the “Screening and Early Diagnosis of COPD” public health project conducted through Shenzhen Municipal Qianhai Shekou Free Trade Zone Hospital. Patients with early COPD were selected as study participants. A prospective, randomized, and controlled method was employed for assigning eligible participants into three groups, i.e., a COPD lung function (LF) I, COPD LF II, and a healthy group, respectively (n = 40 each). The serum content of tumor necrosis factor alpha (TNF-α), interferon-gamma (IFN-γ), interleukin 4 (IL-4), and IL-6 were measured by enzyme-linked immunosorbent assay, and the ratio of IFN-γ/IL-4 treated as a marker for Th1/Th2. The serum concentration of 25-hydroxyl-vit D (25 [OH]D) was quantified by a chemiluminescence assay. Statistical processing was performed, and the correlations between changes in the above parameters with vit D level and LF parameters were examined.

Results: There were differences in FEV1pred%, FEV1/FVC, IFN-γ, IL-4, IL-6 and IFN-γ/IL-4 between the healthy group, the COPD LF I group and the COPD LF II group (p &lt; 0.05). In early COPD, Th1/Th2 cytokines was positively correlated with forced expiratory volume/expected value (FEV1pred%) (r = 0.485, p &lt; 0.001) and forced expiratory volume/forced vital capacity (FEV1/FVC) (r = 0.273, p = 0.018); Th1/Th2 cytokines levels positively correlated with vit D level (r = 0.27, p = 0.02), and 25(OH)D level positively correlated with FEV1pred% (r = 0.695, p &lt; 0.001).

Conclusion: Vitamin D deficiency was ubiquitous in patients with early COPD. It was positively correlated with the FEV1pred% and FEV1/FVC LF parameters. Accordingly, this study provides experimental rationales for the role of vit D in the prevention and control of COPD and the potential anti-inflammatory mechanisms involved.

Chronic Obstructive Pulmonary Disease Patients With High Peripheral Blood Eosinophil Counts Have Better Predicted Improvement in 6MWD After Rehabilitation: A PRELIMINARY STUDY

PURPOSE

The objective of this investigation was to determine whether chronic obstructive pulmonary disease (COPD) patients with high blood eosinophil (EOS) counts had better improvement in 6-min walk test (6MWT) after pulmonary rehabilitation (PR).

METHODS

Fifty COPD patients were randomly assigned to either the rehabilitation group (RG) or the control group (CG). Patients in the RG (8 wk PR + routine medication) and the CG (routine medication) were followed for 32 wk. According to the blood EOS level, the RG was divided into an EOS ≥ 200 cells/μL group and EOS < 200 cells/μL group. The 6MWT distance, Borg Scale, and COPD Assessment Test (CAT) were evaluated before intervention and 8 wk and 32 wk later.

RESULTS

After the 8-wk intervention, 37 patients (19 RG/18 CG) completed the study. At 8-wk and 32-wk follow-up from baseline, a statistically significant difference was found between these two groups in the 6MWT, Borg Scale, and CAT. Compared with baseline, the 6MWT in the RG increased 49.1 ± 40.2 m (95% CI, 29.7-68.5, P < .001) at 8 wk and 60.8 ± 42.1 m (95% CI, 40.5-81.6, P < .001) at 32 wk. In addition, the improvement of 6MWT in the EOS ≥ 200 cells/μL RG group was higher than that in the EOS < 200 cells/μL group (40.1 ± 17.6 m, 95% CI, 36.8-43.4; P = .036) at 32-wk follow-up from baseline.

CONCLUSION

An 8-wk PR can improve the exercise capacity of COPD patients, and the benefits persistent for 24 wk. The improvement in the 6MWT was more significant in COPD patients with a high blood EOS count.

Clinical characteristics of airway impairment assessed by impulse oscillometry in patients with chronic obstructive pulmonary disease: findings from the ECOPD study in China

BACKGROUND

The role of airway impairment assessed by impulse oscillometry (IOS) in patients with chronic obstructive pulmonary disease (COPD) remains unclear. Therefore, this study aimed to analyze the proportion and clinical characteristics of airway impairment assessed by IOS across COPD severities, and explore whether airway impairment is a subtype of COPD.

METHODS

This study was based on cross-sectional data from the ECOPD cohort in Guangdong, China. Subjects were consecutively recruited from July 2019 to August 2021. They filled out questionnaires and underwent lung function tests, IOS and computed tomography (CT). COPD was defined as post-bronchodilator forced expiratory volume in one second/forced vital capacity < lower limit of normal (LLN). Meanwhile, airway impairment was defined as IOS parameters > upper limit of normal or < LLN. On the one hand, Poisson regression was employed to analyze the associations between acute exacerbations of COPD (AECOPD) in the previous year and airway impairment. On the other hand, logistic regression was used to assess differences in CT imaging between patients with IOS parameters' abnormalities and patients with normal IOS parameters.

RESULTS

768 COPD subjects were finally enrolled in the study. The proportion of airway impairment assessed by R₅, R₂₀, R₅-R₂₀, X₅, AX, and F_res was 59.8%, 29.7%, 62.5%, 52.9%, 60.9% and 67.3%, respectively. Airway impairment assessed by IOS parameters (R₅, R₅-R₂₀, X₅, AX, and F_res) in patients with COPD was present across all severities of COPD, particularly in GOLD 3-4 patients. Compared with patients with normal IOS parameters, patients with IOS parameters' abnormalities had more respiratory symptoms, more severe airway obstruction and imaging structural abnormalities. Patients with IOS parameters' abnormalities assessed by R₅ [risk ratio (RR): 1.58, 95% confidential interval (CI): 1.13-2.19, P = 0.007], R₅-R₂₀ [RR: 1.73, 95%CI: 1.22-2.45, P = 0.002], X₅ [RR: 2.11, 95%CI: 1.51-2.95, P < 0.001], AX [RR: 2.20, 95%CI: 1.53-3.16, P < 0.001], and F_res [RR: 2.13, 95%CI: 1.44-3.15, P < 0.001] had a higher risk of AECOPD in the previous year than patients with normal IOS parameters.

CONCLUSIONS

Airway impairment assessed by IOS may be a subtype of COPD. Future studies are warranted to identify the underlying mechanisms and longitudinal progression of airway impairment.

Socioeconomic differentials of trends in the prevalence and economic burden of chronic obstructive pulmonary disease in rural southwest China

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a leading cause of mortality and morbidity, and imposes a substantial financial burden on society. However, few studies have examined the role of individual socioeconomic status (SES) in temporal trends of COPD prevalence and economic cost. This study aimed to uncover the changing prevalence and economic burden of COPD across socioeconomic gradients in rural southwest China.

METHODS

Data were collected from two cross-sectional health interviews and examination surveys administered 10 years apart among individuals aged ≥ 35 years in rural China. A prevalence-based cost-of-illness method was used to estimate the cost of COPD. The individual socioeconomic position (SEP) index was constructed using principal component analysis. Post-bronchodilator spirometry tests were performed for each participant.

RESULTS

From 2011 to 2021, the prevalence of COPD increased from 8.7% to 12.8% (P < 0.01), while the economic cost of COPD increased 1.9-fold. Unit hospital costs and outpatient costs increased 1.57-fold and 1.47-fold, while unit medication costs fell by 10.6%. Increasing prevalence was also observed when the data were stratified by sex, age, ethnicity, level of education, level of income, and SEP (P < 0.05). Men, ethnic minorities, and those with a lower educational level, lower income, or lower SEP had a higher prevalence of COPD than their counterparts both in 2011 and 2021 (P < 0.05). Unit outpatient costs and medication costs increased with patients' SEP in both survey years (P < 0.05).

CONCLUSIONS

The prevalence and economic costs of COPD increased substantially across all socioeconomic gradients in rural southwest China in the decade from 2011 and 2021. Future COPD prevention and management interventions as well as efforts to improve access to affordable COPD medication and treatment should focus in particular on ethnic minority and low SEP populations.

Regional differences in the contribution of smoking, dietary and cooking behaviours to airflow obstruction in China: A population-based case-control study

BACKGROUND AND OBJECTIVE

The major contributing risk factors to airflow obstruction (AO) in China remain largely unknown. We examined the environmental and lifestyle risk factors of unrecognized AO in the baseline of a population-based cohort drawn from 115 urban and rural communities across 12 provinces in China.

METHODS

Amongst 46,285 adults recruited from 2005 to 2009, 3686 were identified with AO on spirometry (defined by the ratio of forced expiratory volume in the first second to forced vital capacity <0.7) and without known chronic lung disease. These cases were age- and sex-matched to 11,129 controls with normal spirometry and no chronic lung disease from the same community. Conditional multivariable adjusted OR and population attributable fraction (PAF) were calculated for each identified risk factor and their combined effect.

RESULTS

Compared to controls, smoking initiation age <20 years (OR 1.22 [95% CI 1.01-1.48]), smoking duration ≥40 years (OR 1.82 [1.50-2.22]), low vegetables (OR 1.86 [1.67-2.07]) and fruits (OR 1.14 [1.02-1.29]) intake, cooking with biomass fuels (OR 2.54 [2.32-2.78]) and poor kitchen ventilation (OR 1.37 [1.19-1.58]) were significantly associated with elevated risks of unrecognized AO. The combined effect of these lifestyle factors significantly elevated the odds by 25 fold (18.6-34.3). The addition of prior tuberculosis and low socioeconomic status further increased the odds to 40.1 (28.2-57.0) and the PAF to 66.7% (51.1-78.1).

CONCLUSION

Smoking, unhealthy diet, biomass cooking fuels and low socioeconomic status are strongly associated with AO. Addressing these risk factors could substantially reduce the burden of AO in China.

Nurses in China lack knowledge of inhaler devices: A cross-sectional study

Objective: To understand the level of knowledge about inhaler devices among medical staff. Methods: This study evaluated the knowledge of inhalation therapy and the use of inhaler devices among nurses in China. We administered a new self-designed online questionnaire to 1,831 nurses. The questionnaire comprised 11 questions, including the storage location of inhaler devices, steps involved in using inhaler devices, and common errors when using various devices. Results: Among the 1,831 participants, 816(44.57%), 122(6.66%), and 893(48.77%) nurses worked in community, secondary, and tertiary hospitals, respectively. Adequate knowledge of inhaler devices was demonstrated by 20.10%, 8.20%, and 13.10% of nurses working in community, secondary, and tertiary hospitals, respectively. Of the nurses working in community hospitals, 27.70% knew the key points for using inhalers compared to 15.57% in secondary hospitals and 23.18% in tertiary hospitals (p < 0.01). Only 9.50%-26.00% of participants chose correct answers to the 9 questions about the use of inhalers. The accuracy rate of the responses was generally low, and the highest accuracy rate was 26.00%. Conclusion: Knowledge of inhalation therapy was better among nurses working in community hospitals than among those working in high-level hospitals. This is because of the clearer division of work and higher workload in high-level hospitals. Overall, nurses' knowledge of inhalation therapy is low. Furthermore, knowledge about inhaler devices should be strengthened among nurses in Chinese hospitals. It is necessary to create training opportunities for nurses in China to increase their awareness and knowledge regarding the management of chronic respiratory diseases.

Treatment patterns in patients with stable COPD in China: analysis of a prospective, 52-week, nationwide, observational cohort study (REAL)

BACKGROUND

Underdiagnosis and undertreatment pose major barriers to optimal management of chronic obstructive pulmonary disease (COPD) in China.

OBJECTIVE

The REAL trial was performed to generate reliable information on real-world COPD management, outcomes and risk factors among Chinese patients. Here, we present study outcomes related to COPD management.

DESIGN

It is a 52-week, prospective, observational, multicentre study.

METHODS

Outpatients (aged ⩾40 years) enrolled from 50 secondary and tertiary hospitals across six geographic regions of China were followed up for 12 months, with two onsite visits and by telephone every 3 months following baseline.

RESULTS

Between June 2017 and January 2019, 5013 patients were enrolled and 4978 included in the analysis. Mean [standard deviation (SD)] age was 66.2 (8.9) years, the majority of patients were male (79.5%) and mean (SD) time since COPD diagnosis was 3.8 (6.2) years. The most common treatments at each study visit were inhaled corticosteroids/long-acting beta-agonists (ICSs/LABAs; 28.3-36.0%), long-acting muscarinic antagonists (LAMAs; 13.0-16.2%) and ICS/LABA + LAMA (17.5-18.7%), but up to 15.8% of patients at each visit received neither ICS nor long-acting bronchodilators. The use of ICS/LABA, LAMA and ICS/LABA + LAMA differed across regions and hospital tiers; up to fivefold, more patients received neither ICS nor long-acting bronchodilators in secondary (17.3-25.4%) versus tertiary hospitals (5.0-5.3%). Overall, rates of nonpharmacological management were low. Direct treatment costs increased with disease severity, but the proportion of direct treatment costs incurred due to maintenance treatment decreased with disease severity.

CONCLUSION

ICS/LABA, LAMA and ICS/LABA + LAMA were the most frequently prescribed maintenance treatments for patients with stable COPD in China, although their use differed between region and hospital tier. There is a clear need for improved COPD management across China, particularly in secondary hospitals.

REGISTRATION

The trial was registered on 20 March 2017 (ClinicalTrials.gov identifier: NCT03131362; https://clinicaltrials.gov/ct2/show/NCT03131362).

PLAIN LANGUAGE SUMMARY

Treatment patterns in patients with COPD in ChinaBackground: Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory lung disease characterized by progressive and irreversible airflow limitation. In China, many patients with this disease do not receive a diagnosis or appropriate treatment.Objective: This study aimed to generate reliable information on the treatment patterns among patients with COPD in China to help inform future management strategies.Study design and methods: Patients (aged ⩾40 years) were enrolled from 50 hospitals across 6 regions of China and physicians collected data over the course of 1 year during routine outpatient visits.Results: The majority of patients were receiving long-acting inhaled treatments, which are recommended to prevent worsening of the disease. Up to 16% of patients in this study, however, did not receive any of these recommended treatments. The proportion of patients who received long-acting inhaled treatments differed across regions and hospital tiers; there were about five times more patients in secondary hospitals (about 25%) who did not receive these treatments compared with those in tertiary hospitals (about 5%). Guidelines recommend that pharmacological treatment should be complemented by nondrug treatment, but this was only received by a minority of patients in this study. Patients with higher disease severity incurred greater direct treatment costs compared with those with milder disease. Maintenance treatment costs made up a smaller proportion of overall direct costs for patients with higher disease severity (60-76%) compared with patients with milder disease (81-94%).Conclusion: Long-acting inhaled treatments were the most frequently prescribed maintenance treatments among patients with COPD in China, but their use differed between region and hospital tier. There is a clear need to improve disease management across China, especially in secondary hospitals.

Development and validation of nomogram including high altitude as a risk factor for COPD: A cross-sectional study based on Gansu population

Background

Chronic Obstructive Pulmonary Disease (COPD) is a common and harmful disease that requires an effective tool to early screen high-risk individuals. Gansu has unique environments and customs, leading to the different prevalence and etiology of COPD from other regions. The association between altitude and COPD once attracted epidemiologists' attention. However, the prevalence in Gansu and the role of altitude are still unclarified.

Methods

In Gansu, a multistage stratified cluster sampling procedure was utilized to select a representative sample aged 40 years or older. The questionnaire and spirometry examination were implemented to collect participants' information. The diagnosis and assessment of COPD were identified by the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criterion, while post-bronchodilator FEV₁/FVC < LLN was for sensitivity analysis. Furthermore, the effect of high altitude on COPD was evaluated by the logistic regression model after propensity score matching (PSM). Finally, the participants were randomly divided into training and validation sets. The training set was used to screen the relative factors and construct a nomogram which was further assessed by the receiver operating characteristic (ROC) curve, calibration curve, and decision curve analysis (DCA) in the two sets.

Results

There were 2,486 eligible participants in the final analysis, of which 1,584 lived in low altitudes and 902 lived in high altitudes. Based on the GOLD criterion, the crude and standardized prevalences in Gansu were 20.4% (18.7-22.0) and 19.7% (17.9-21.6). After PSM, the logistic regression model indicated that high altitude increased COPD risk [PSM OR: 1.516 (1.162-1.978)]. Altitude, age, sex, history of tuberculosis, coal as fuel, and smoking status were reserved for developing a nomogram that demonstrated excellent discrimination, calibration, and clinical benefit in the two sets.

Conclusions

COPD has become a serious public health problem in Gansu. High altitude is a risk factor for COPD. The nomogram has satisfactory efficiency in screening high-risk individuals.

Real-World COPD Management Over 3 Years at the Community Health Service Center of Shanghai During the COVID-19 Pandemic in China

Objective

To evaluate the real-world situation for the management of chronic obstructive pulmonary disease (COPD) and poorly controlled disease risk factors in the Chinese community.

Methods

This retrospective multicentre study analysed data from COPDMICand MICHC in Shanghai Songjiang District, Shanghai, China. The differences in COPD Assessment Test (CAT), the modified Medical Research Council (mMRC) dyspnea scale, and the number of emergency cases, emergency visits, inpatient cases, and hospitalisations from January 2018 to December 2020 were analysed. The impact of coronavirus disease 2019 (COVID-19) on COPD management was also assessed.

Results

For 2020 versus 2018, analysis of 468 COPD cases from COPDMIC matched with MICHC data showed significantly more patients with improved mMRC grades, significantly fewer emergency cases and emergency visits, and significantly fewer hospitalisation cases and hospitalisations. Differences in the number of emergency visits and hospitalisations per capita were statistically significant. Compared to GOLD 3-4, GOLD 1-2 patients showed significant improvements in CAT score, mMRC grade, the number of emergency visits and hospitalisations per capita. Treatment adherence from 2018 to 2020 was 25%, 29.1%, and 6.8%, and the proportion of medication regimens consistent with guidelines was 43.44%, 50.98%, and 71.87%, respectively. Higher treatment adherence resulted in significantly improved CAT scores and mMRC grades and fewer emergency department visits and hospitalisations per capita.

Conclusion

Combined with remote management tools, patients with COPD achieved continuous improvement in symptoms and exacerbations over 3 years. In the context of COVID-19 prevention/control measures, improvements were significant for patients with GOLD 1-2 COPD but limited with GOLD 3-4. Pharmacologic treatment significantly improved clinical symptoms and reduced emergency visits and hospitalisations. Severe airflow limitation and poor adherence to pharmacologic treatment were important risk factors for lack of disease remission.

Comparing the Performance of Two Screening Questionnaires for Chronic Obstructive Pulmonary Disease in the Chinese General Population

Purpose

Screening questionnaires can help identify individuals at a high risk of COPD. This study aimed to compare the performance of the COPD population screener (COPD-PS) and COPD screening questionnaire (COPD-SQ) on the general population as a full cohort and stratified by urbanization.

Methods

We recruited subjects who underwent a health checkup at urban and rural community health centers in Beijing. All eligible subjects completed the COPD-PS and COPD-SQ, then spirometry. Spirometry-defined COPD was defined as a post-bronchodilator FEV₁/FVC<70%. Symptomatic COPD was defined as a post-bronchodilator FEV₁/FVC<70% and respiratory symptoms. Receiver operating characteristic (ROC) curve analysis compared the discriminatory power of the two questionnaires, and stratified by urbanization.

Results

We identified 129 spirometry-defined and 92 symptomatic COPD cases out of 1350 enrolled subjects. The optimal cut-off score for the COPD-PS was 4 for spirometry-defined and 5 for symptomatic COPD. The optimum cut-off score for the COPD-SQ was 15 for both spirometry-defined and symptomatic COPD. The COPD-PS and COPD-SQ had similar AUC values for spirometry-defined (0.672 vs 0.702) and symptomatic COPD (0.734 vs 0.779). The AUC of the COPD-SQ tended to be higher in rural areas than that of the COPD-PS for spirometry-defined COPD (0.700 vs 0.653, P = 0.093).

Conclusion

The COPD-PS and COPD-SQ had comparable discriminatory power for detecting COPD in the general population while the COPD-SQ performed better in rural areas. A pilot study for validating and comparing the diagnostic accuracy of different questionnaires is required when screening for COPD in a new environment.

Characteristics of Lung Function and Prevalence of Airflow Obstruction Among Individuals Aged 18-74 Years - Beijing, China, 2017-2018

What is already known about this topic?

Airflow obstruction is the hallmark of many chronic respiratory diseases and may indicate the potential for the development of other progressive diseases. There are currently no representative studies of lung function in Beijing. An up-to-date estimation of the characteristics of lung function and airflow obstruction is thus needed.

What is added by this report?

The estimated prevalence of airflow obstruction was 14.68% in Beijing, 2017-2018. The values of vital capacity, forced vital capacity, and forced expiratory volume in the first second were 3.09 L, 2.66 L, 2.22 L, respectively.

What are the implications for public health practice?

Effective public health strategy for lung in Beijing should target older people, current or former smokers, and individuals who live in urban environments, have a low education level, exhibit a high smoking index, and/or have an abnormal body mass index.

DALY trend and predictive analysis of COPD in China and its provinces: Findings from the global burden of disease study

Background

Chronic obstructive pulmonary disease (COPD) is the most common chronic respiratory disease in the world, especially in China. Few studies have explored the trend of COPD in China and its provinces. This study aimed to demonstrate and predict the trend of COPD DALY in China and its provinces based on the global burden of disease (GBD) data.

Methods

The data on COPD disability-adjusted life year (DALY) were collected from GBD 2017, GBD 2019, and the National Bureau of Statistics of China. The age-standardized rate (ASR) was used to evaluate the trend of COPD DALY by gender, age, and risk factors in China and its provinces. In addition, the trend of COPD considering the aging population in the next 10 years was also predicted.

Results

In China, the COPD DALY was 20.4 million in 2017, which decreased to 24.16% from 1990 to 2017. Most provinces showed a downward trend, with the exception of Taiwan which increased by 127.78%. The ASR of DALY was 1445.53 per 100,000 people in 2017 and demonstrated a significant decrease. Among all provinces, only Taiwan (97.78%) and Hubei (2.21%) demonstrated an increased trend of ASR. In addition, Tibet ranked third with a decline of 56.95%, although its ASR was the highest in 1990. Smoking and air pollution were the main risk factors for COPD and varied with regions, gender, and age. The proportion of COPD DALY attributable to smoking was higher in the middle-aged and elderly male population and did not decrease in China. Moreover, the ASR attributable to air pollution of the elderly decreased significantly in China. Socio-demographic index (SDI) and educational level were also found to be related to ASR. By predicting the ASR trend in the next 10 years, we found that the ASR attributable to smoking might increase significantly among men. The ASR attributable to air pollution showed a significant decrease in women. Unfortunately, ASR attributable to second-hand smoke was found to increase in women.

Conclusion

Chronic obstructive pulmonary disease is the leading contributor to the burden of global diseases. Although China and its provinces demonstrated a downward trend of COPD DALY, some provinces still faced challenges. Moreover, ASR attributable to risk factors was different in regions, gender, age, and years. The predicted trend of COPD was also different. Therefore, more targeted strategies should be formulated to reduce the burden of COPD in China and its provinces.

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.

The path to healthy ageing in China: a Peking University-Lancet Commission

Around the world, populations are ageing at a faster pace than in the past and this demographic transition will have impacts on all aspects of societies. In May 2020, the UN General Assembly declared 2021–2030 the Decade of Healthy Ageing, highlighting the importance for policymakers across the world to focus policy on improving the lives of older people, both today and in the future. While rapid population ageing poses challenges, China’s rapid economic growth over the last forty years has created space for policy to assist older persons and families in their efforts to improve health and well-being at older ages. As China is home to 1/5 of the world’s older people, China is often held up as an example for other middle-income countries. This Commission Report aims to help readers to understand the process of healthy ageing in China as a means of drawing lessons from the China experience. In addition, with the purpose of informing the ongoing policy dialogue within China, the Commission Report highlights the policy challenges on the horizon and draws lessons from international experience.

Significance of Cardiometabolic Index in Predicting Acute Exacerbation of Stable Chronic Obstructive Pulmonary Disease for Clinical Nursing

Objective

To evaluate the level of cardiometabolic index (CMI) to predict the risk of acute exacerbation in patients with stable chronic obstructive pulmonary disease (COPD), and to provide a basis for early identification and intervention of high-risk patients in clinical nursing work.

Methods

Patients with stable chronic obstructive pulmonary disease who were admitted to the outpatient department of respiratory medicine in a tertiary hospital or followed up after discharge from January to December 2021 were retrospectively selected. CMI was measured and statistical analysis was performed to determine the optimal threshold for predicting acute exacerbation of chronic obstructive pulmonary disease.

Results

A total of 63 patients with chronic obstructive pulmonary disease were enrolled. The median number of episodes in the previous year was 1.00; 44 patients had ≥1 acute exacerbation. The CMI was positively correlated with the frequency of acute exacerbations and the British Medical Research Council (mMRC) score in the previous year, and negatively correlated with the percentage of forced expiratory volume in 1 second to the predicted value (FEV1% PRED). The cut-off point of CMI for predicting acute exacerbations in stable chronic obstructive pulmonary disease patients was 2.05, with a sensitivity of 0.864% and specificity of 0.842%. It is a risk factor for acute exacerbation in COPD patients.

Conclusion

CMI can be used as a biological index to predict acute exacerbation in stable COPD patients. Clinical nursing needs to evaluate patients' CMI and provide personalized nursing intervention for patients with CMI≥2.05.

Clinical characteristics and gene mutation profiles of chronic obstructive pulmonary disease in non-small cell lung cancer

Purpose

The coexistence of chronic obstructive pulmonary disease (COPD) often leads to a worse prognosis in patients with non-small cell lung cancer (NSCLC). Meanwhile, approaches targeting specific genetic alterations have been shown to significantly improve the diagnosis and treatment outcomes of patients with NSCLC. Herein, we sought to evaluate the impact of COPD on the clinical manifestations and gene mutation profiles of NSCLC patients with both circulating tumor (ctDNA) and tumor DNA (tDNA).

Materials and methods

The influence of COPD on clinical features was observed in 285 NSCLC cohorts suffering from NSCLC alone, NSCLC coexisting with COPD, or NSCLC coexisting with prodromal changes in COPD (with emphysema, bullae, or chronic bronchitis). The gene mutation profiles of specific 168 NSCLC-related genes were further analyzed in the NSCLC sub-cohorts with formalin-fixed and paraffin-embedded tumor DNA (FFPE tDNA) samples and plasma circulating tumor DNA (PLA ctDNA) samples. Moreover, mutation concordance was assessed in tDNA and paired ctDNA of 110 NSCLC patients.

Results

Relative to patients with NSCLC alone, patients with NSCLC coexisting with COPD and prodromal changes presented with worse lung functions, more clinical symptoms, signs and comorbidities, and inconsistent gene mutation profiles. In addition, patients in the latter two groups exhibited a higher average frequency of gene mutation. Lastly, mutation concordance between tDNA and ctDNA samples was significantly reduced in NSCLC patients coexisting with COPD.

Conclusions

Collectively, our findings revealed that coexistence of COPD leads to worse clinical manifestations and altered gene mutation profiles in patients with NSCLC. Additionally, for NSCLC patients with COPD, the use of ctDNA instead of tDNA may not be the most efficient approach to identifying gene mutations.

Cost-Effectiveness Analysis of the TCM "Yupingfeng Granules" in the Treatment of Acute Exacerbations of COPD Based on a Randomized Clinical Trial

Introduction

Traditional Chinese medicine (TCM) is becoming increasingly important as it provides further options for treating many diseases worldwide. The TCM "Yupingfeng" has been used in China for over 800 years, and its clinical efficacy and safety for COPD treatment have been proven in previous studies. The objective of this study was to compare the long-term cost-effectiveness of Yupingfeng granules and the current conventional treatment for COPD patients in China.

Methods

A Markov model was constructed from the perspective of the Chinese healthcare system using TreeAge Pro 2011. The model cycle length was 12 months, and the cycle time was set to 10 years. Data from a randomized controlled trial were used to generate the number of acute exacerbations, COPD assessment test (CAT) score and actual medication used. The state transition probabilities, costs and quality-adjusted life years (QALYs) were derived from available sources. A threshold of 72,447 yuan per QALY gained was used as a cost-effectiveness criterion. One-way and probabilistic sensitivity analyses were conducted to verify the model. In addition, the cost-effectiveness of a 35-year cycle was evaluated as a scenario analysis.

Results

In the basic-case analysis, the ICER of adding Yupingfeng granules to the current conventional treatment drugs was ¥2123.04 per QALY, which was less than the threshold (one-time per capita GDP).Sensitivity analyses showed the results to be robust. Probabilistic sensitivity analysis showed that the probability of the ICER being less than the one-time per capita GDP threshold was 100%. In the scenario analysis, the incremental cost-effectiveness was ¥12,051.27 per QALY which was also under the one-time per capita GDP.

Conclusion

By reducing the number of acute exacerbations of COPD, thereby correspondingly reducing the follow-up treatment cost, Yupingfeng granules combined with conventional treatment were found to provide a cost-effective therapeutic strategy for COPD.

Evaluation of Risk Factors for Chronic Obstructive Pulmonary Disease in the Middle-Aged and Elderly Rural Population of Northeast China Using Logistic Regression and Principal Component Analysis

Purpose

To investigate the environmental, immune, and inflammatory factors associated with chronic obstructive pulmonary disease (COPD) in middle-aged and older Chinese individuals.

Patients and Methods

A community-based case–control study was conducted among 471 patients with COPD and 485 controls. The information on COPD of the participants was collected through face-to-face interviews, and serum samples were measured at the laboratory. The main risk factors for COPD were analyzed using principal component analysis (PCA) and logistic regression.

Results

Nine hundred and fifty-six respondents were included in the analysis. The results of the PCA-logistic regression analysis showed significant differences in the environmental factors, medical history, and serum C-reactive protein (CRP) levels between patients and controls. COPD was markedly more usual in those with smoking index >200 (OR, 1.42; 95% CI, 1.28–1.57); exposure to outdoor straw burning (OR, 1.64; 95% CI, 1.47–1.83); use of coal, wood, and straw indoors (OR, 2.31; 95% CI, 1.92–2.78); history of respiratory disease and coronary heart disease (OR, 3.58; 95% CI, 3.12–4.10), congestive heart failure (OR, 1.23; 95% CI, 1.09–1.38), and cerebrovascular disease (OR, 1.15; 95% CI,1.02–1.31); and higher serum level of CRP (OR, 1.20; 95% CI, 1.11–1.30). Compared to the logistic regression analysis, PCA logistic regression analysis identified more important risk factors for COPD.

Conclusion

PCA-logistic regression analysis was first utilized to explore the influencing factors among rural residents in Northeast China Environmental aged 40 years and above, it was found that environmental factors, medical history, and serum CRP levels mainly affected the prevalence of COPD.

The association between small airway dysfunction and aging: a cross-sectional analysis from the ECOPD cohort

BACKGROUND

Aging has been evidenced to bring about some structural and functional lung changes, especially in COPD. However, whether aging affects SAD, a possible precursor of COPD, has not been well characterized.

OBJECTIVE

We aimed to comprehensively assess the relationship between aging and SAD from computed tomography, impulse oscillometry, and spirometry perspectives in Chinese.

METHODS

We included 1859 participants from ECOPD, and used a linear-by-linear association test for evaluating the prevalence of SAD across various age subgroups, and multivariate regression models for determining the impact of age on the risk and severity of SAD. We then repeated the analyses in these subjects stratified by airflow limitation.

RESULTS

The prevalence of SAD increases over aging regardless of definitional methods. After adjustment for other confounding factors, per 10-yrs increase in age was significantly associated with the risk of CT-defined SAD (OR 2.57, 95% CI 2.13 to 3.10) and the increase in the severity of air trapping (β 2.09, 95% CI - 0.06 to 4.25 for LAA_-856), airway reactance (β - 0.02, 95% CI - 0.04 to - 0.01 for X5; β 0.30, 95% CI 0.13 to 0.47 for AX; β 1.75, 95% CI 0.85 to 2.66 for Fres), as well as the decrease in expiratory flow rates (β - 3.95, 95% CI - 6.19 to - 1.71 for MMEF%predicted; β - 5.42, 95% CI - 7.88 to - 2.95 for FEF₅₀%predicted) for SAD. All these associations were generally maintained in SAD defined by IOS or spirometry. After stratification of airflow limitation, we further found that the effect of age on LAA_-856 was the most significant among almost all subgroups.

CONCLUSIONS

Aging is significantly associated with the prevalence, increased risk, as well as worse severity of SAD. CT may be a more optimal measure to assess aging-related SAD. The molecular mechanisms for the role of aging in SAD need to be explored in the future. Trial registration Chinese Clinical Trial Registry ChiCTR1900024643. Registered on 19 July 2019.

Influences of Two FEV1 Reference Equations (GLI-2012 and GIRH-2017) on Airflow Limitation Classification Among COPD Patients

Objective

Methods

Results

Conclusion

Modeling the Health and Economic Burden of Chronic Obstructive Pulmonary Disease in China From 2020 to 2039: A Simulation Study

OBJECTIVES

Despite a growing prevalence of respiratory diseases in recent decades in China, limited evidence is available on the health and economic burden of chronic obstructive pulmonary disease (COPD). We estimated the 20-year health and economic burden of COPD in China from 2020 to 2039.

METHODS

We created a probabilistic dynamic open-cohort Markov model of COPD for the Chinese population aged ≥40 years. Projections of population growth and urbanization rates were obtained from the United Nations Population Division. Other parameter inputs including smoking prevalence, COPD prevalence and severity distributions, disease-related costs, and utility weights were obtained from the most recent published literature. We modeled number of COPD patients, excess mortality due to COPD, exacerbations, COPD-attributable losses of quality-adjusted life-years, and direct and indirect COPD costs over the 20 years.

RESULTS

The number of COPD patients was projected to increase from 88.3 million in 2020 to 103.3 million in 2039. The projected total losses of quality-adjusted life-years and the excess mortality due to COPD were, respectively, estimated to be 253.6 million and 3.9 million over the 20 years. The projected 20-year total discounted direct and indirect costs of COPD were, respectively, $3.1 trillion and $360.5 billion. The projected health and economic burden was higher in males and urban areas.

CONCLUSIONS

COPD is projected to inflict a substantial burden to the society and the health care system in China. Effective strategies for prevention and early management of COPD are needed to mitigate the forthcoming disease burden.

Early detection of COPD based on graph convolutional network and small and weakly labeled data

Chronic obstructive pulmonary disease (COPD) is a common disease with high morbidity and mortality, where early detection benefits the population. However, the early diagnosis rate of COPD is low due to the absence or slight early symptoms. In this paper, a novel method based on graph convolution network (GCN) for early detection of COPD is proposed, which uses small and weakly labeled chest computed tomography image data from the publicly available Danish Lung Cancer Screening Trial database. The key idea is to construct a graph using regions of interest randomly selected from the segmented lung parenchyma and then input it into the GCN model for COPD detection. In this way, the model can not only extract the feature information of each region of interest but also the topological structure information between regions of interest, that is, graph structure information. The proposed GCN model achieves an acceptable performance with an accuracy of 0.77 and an area under a curve of 0.81, which is higher than the previous studies on the same dataset. GCN model also outperforms several state-of-the-art methods trained at the same time. As far as we know, it is also the first time using the GCN model on this dataset for COPD detection.

Global disease burden of COPD from 1990 to 2019 and prediction of future disease burden trend in China

OBJECTIVES

This study aimed to assess and predict the disease burden attributable to chronic obstructive pulmonary disease (COPD) in a timely, comprehensive, and reliable manner, thereby mitigating the health hazards of COPD.

STUDY DESIGN AND METHODS

Data on the disease burden owing to COPD from 1990 to 2019 were extracted from the Global Burden of Disease (GBD) Study 2019. Linear regression analysis was used to calculate the estimated annual percentage change (EAPC) in the age-standardized rates. Non-parametric tests were used for subgroup analysis. The Bayesian age-period-cohot (BAPC) model integrated nested Laplace approximations to predict the disease burden over the next 25 years. Sensitivity analysis was performed using the Norpred APC model.

RESULTS

Globally, the COPD-related age-standardized incidence rate decreased from 216.48/100,000 in 1990 to 200.49/100,000 in 2019, with an EAPC of -0.33. But the number of new cases increased from 8,722,966 in 1990 to 16, 214, 828 in 2019. Trends in prevalence, deaths, and disability-adjusted life years (DALYs) were the same as incidence. There were significant differences in disease burden between the genders and all age groups (P < 0.05) in China. The projections suggested that the COPD-related number of new cases and deaths in China would increase by approximately 1.5 times over the next 25 years.

CONCLUSIONS

The number of incidence, prevalence, deaths, and DALYs had all increased in China in the past and would continue to grow over the next 25 years. Therefore, measures should be taken to target risk factors and high-risk groups.

Exploring influencing factors of chronic obstructive pulmonary disease based on elastic net and Bayesian network

This study aimed to construct Bayesian networks (BNs) to analyze the network relationships between COPD and its influencing factors, and the strength of each factor's influence on COPD was reflected through network reasoning. Elastic Net and Max-Min Hill-Climbing (MMHC) algorithm were adopted to screen the variables on the surveillance data of COPD among residents in Shanxi Province, China from 2014 to 2015, and construct BNs respectively. 10 variables finally entered the model after screening by Elastic Net. The BNs constructed by MMHC showed that smoking status, household air pollution, family history, cough, air hunger or dyspnea were directly related to COPD, and Gender was indirectly linked to COPD through smoking status. Moreover, smoking status, household air pollution and family history were the parent nodes of COPD, and cough, air hunger or dyspnea represented the child nodes of COPD. In other words, smoking status, household air pollution and family history were related to the occurrence of COPD, and COPD would make patients’ cough, air hunger or dyspnea worse. Generally speaking, BNs could reveal the complex network linkages between COPD and its relevant factors well, making it more convenient to carry out targeted prevention and control of COPD.

Increasing prevalence and burden of bronchiectasis in urban Chinese adults, 2013-2017: a nationwide population-based cohort study

Background

While the prevalence and disease burden of bronchiectasis are increasing, data in the world’s largest population are lacking. We aimed to investigate the prevalence and disease burden of bronchiectasis in Chinese adults.

Methods

We conducted a population-based study using data between 2013 and 2017 from the national databases of Urban Employee Basic Medical Insurance and Urban Resident Basic Medical Insurance in China. Data from over 380 million patients aged 18 years and older during the study period were analyzed, and a total of 383,926 bronchiectasis patients were identified. Primary outcomes included the age- and sex-specific prevalence of bronchiectasis. Annual visits and hospitalizations, as well as annual costs were also calculated.

Results

The prevalence of bronchiectasis in Chinese adults increased 2.31-fold, from 75.48 (62.26, 88.69) per 100,000 in 2013 to 174.45 (137.02, 211.88) per 100,000 in 2017. The increase was more remarkable for patients aged over 50 years in both genders. The per-capita total cost and hospitalization cost of patients with bronchiectasis increased 2.18-fold and 1.83-fold from 2013 to 2017, respectively, mostly driven by non-bronchiectasis costs. The average annual hospitalization ranged from 1.20 to 1.24 times during the 5 years.

Conclusion

The prevalence and disease burden of bronchiectasis in Chinese urban adults ≥ 18 years had increased significantly between 2013 and 2017.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-02023-8.

Association Between Serum Total Bilirubin Level and Lung Function Decline in Patients with COPD: Results from a Pooled Study

Background

Methods

Results

Conclusion

Severity distribution and treatment of chronic obstructive pulmonary disease in China: baseline results of an observational study

Background

Chronic obstructive pulmonary disease (COPD) receives low awareness and is undertreated in China. Understanding the burden and treatment of COPD across the nation is important for improving quality of care for this disease. This study aims to reveal the current situation of COPD severity distribution and management across China.

Methods

Baseline data from REALizing and Improving Management of Stable COPD in China, a multicentre, prospective, longitudinal, observational study, were analysed. Patients diagnosed with COPD as per Global Initiative for Chronic Obstructive Lung Disease 2016 (GOLD 2016) criteria were enrolled from 50 randomly selected hospitals (tertiary, 25; secondary, 25) across six geographical regions. Data were collected in routine clinical settings.

Results

Between 15 December 2017 and 6 August 2020, 5013 patients were enrolled and 4978 included in the full analysis set. Of these, 2459 (49.4%) reported ≥ 1 exacerbation within 12 months prior to study enrolment, with a mean annual rate of 0.9/patient, including 0.2/patient and 0.5/patient leading to emergency room visits and hospitalisation, respectively. Spirometry graded 458 (10.1%), 1886 (41.7%), 1558 (34.5%), and 616 (13.6%) were GOLD stage I–IV, and 536 (11.4%), 1034 (22.0%), 563 (12.0%), and 2566 (54.6%) were classified as GOLD 2016 Group A–D, respectively, without evident regional variations. Inhaled corticosteroids plus long-acting beta₂-agonist (ICS/LABA, 1316 [26.4%]), ICS/LABA plus long-acting muscarinic antagonist (ICS/LABA + LAMA, 871 [17.5%]), and LAMA (754 [15.1%]) were prescribed at high rates across all groups and regions. Medications not recommended by GOLD were commonly prescribed (TCM, 578 [11.6%]; others, 951 [19.1%]), and 681 (13.7%) were not given ICS or long-acting bronchodilators.

Conclusions

Disease burden among Chinese COPD outpatients is high. Improved guideline adherence for COPD treatment is needed.

Trial registration ClinicalTrials.gov identifier, NCT03131362.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-02021-w.

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 .

Medicinal Foods, YT and RH Combination, Suppress Cigarette Smoke-Induced Inflammation and Oxidative Stress by Inhibiting NF-κB/ERK Signaling Pathways

Background

Cigarette smoke is a risk factor for Chronic Obstructive Pulmonary Disease (COPD). Given the lack of COPD curative treatment, dietary management for COPD patients has become important. This study investigated whether the medicinal foods (YT and RH) could suppress cigarette smoke exposure-induced inflammation and oxidative stress.

Methods

Chronic pulmonary inflammation in male C57 mice was induced by a 4-week exposure to cigarette smoke (CS). The medicinal foods YT and RH were orally administered 1 week prior to CS exposure. The protective effects were assessed by measuring the pulmonary function and histopathological evaluations. Inflammatory cell numbers and cytokines levels in BALF and blood serum were analyzed by enzyme-linked immunosorbent assay (ELISA). Malondialdehyde (MDA) and superoxide dismutase (SOD) levels of the lung were analyzed. Furthermore, the levels of phosphorylated ERK and NF-κB in both the mice lungs and RAW264.7 cells were also detected.

Results

YT and RH combination (YT + RH) significantly improved pulmonary function and suppressed the inflammation, including cell number and cytokines in BALF relative to the CS group; histological examination revealed protective effects of YT + RH in the lungs of mice exposed to CS. Moreover, the MDA level in the lung of the YT + RH group of mice was lower, the SOD activity was higher, and in vitro treatment of YT and RH combination attenuated reactive oxygen species (ROS) expression in mouse macrophage RAW264.7 cells stimulated with cigarette smoke (CSE). YT + RH combination significantly reduced the expression of pNF-κB and pERK in the lung tissues and macrophage stimulated with CSE.

Conclusions

YT and RH combination attenuates cigarette smoke-induced inflammation and oxidative stress through inhibition of the NF-κB/ERK signaling pathway.

Validity of a portable spirometer in the communities of China

Background

The lack of simple and affordable spirometry has led to the missed and delayed diagnoses of chronic respiratory diseases in communities. The PUS201P is a portable spirometry developed to solve this problem.

Objective

We aimed to verify the consistency of the PUS201P spirometer with conventional Jaeger spirometer.

Methods

In this cross-sectional study, we randomly recruited 202 subjects aged > 40 years. Testing with the portable spirometry and conventional spirometry were performed on all participants. We compared forced expiratory volume in one second (FEV₁), forced vital capacity (FVC), FEV₁/FVC measured by the PUS201P device with the conventional spirometer. Pearson correlation coefficient and Interclass Correlation Coefficient (ICC) were assessed to confirm the consistency of the measures from two instruments. Bland–Altman graph was created to assess the agreement of the measures from two devices.

Results

202 participants were included in this study. The ICC on FEV₁, FVC, FEV₁/FVC measured by the portable spirometer and the conventional spirometer were 0.95 (95% confidence interval [CI]: 0.94–0.96), 0.92 (95% CI: 0.90–0.94], 0.93 (95% CI: 0.91–0.95), respectively. The Bland–Altman plots showed that the mean difference between the measures from two spirometers are always located in the 95% limits of agreement.

Conclusions

Our results support that the measures from the portable spirometer and the conventional spirometer have a good agreement and reproducibility. And the portable spirometer is a reliable tool to screen and diagnose chronic airway diseases in the primary care settings.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-022-01872-9.

An Evaluation of the Pharmacokinetics, Safety, and Tolerability of Aclidinium/Formoterol Fixed-Dose Combination Administered in Chinese Patients with Moderate-to-Severe Chronic Obstructive Pulmonary Disease

Background and Objectives

The aim of this study was to evaluate the pharmacokinetics, safety, and tolerability of aclidinium bromide/formoterol fumarate in patients from China with moderate-to-severe chronic obstructive pulmonary disease (COPD).

Methods

In this open-label, repeat-dose, 5-day pharmacokinetic study (NCT03276078) of inhaled aclidinium bromide/formoterol fumarate 400/12 µg twice daily, plasma concentrations of aclidinium, formoterol, and two aclidinium metabolites (LAS34823, LAS34850) were assessed (days 1 and 5). Adverse event (AE) data were collected.

Results

Twenty patients (15 [75%] males) with a mean age of 59.2 years were included. Median (range) time to maximum concentration on days 1 and 5 was 0.08 (0.08–0.50) and 0.08 (0.08–0.50) h, respectively, for aclidinium; and 1.00 (0.08–3.00) and 0.08 (0.08–1.50) h, respectively, for formoterol. Mean elimination half-life and accumulation ratio for area under the concentration–time curve during a dosage interval (AUC_τ) was 19.42 h and 2.0, respectively, for aclidinium; and 14.06 h and 1.4, respectively, for formoterol. Steady-state maximum concentration (C_max,ss) and AUC_τ on day 5 were 60.86 pg/mL and 168.80 h·pg/mL, respectively, for aclidinium; and 6.47 pg/mL and 31.98 h·pg/mL, respectively, for formoterol. Aclidinium produced high coefficients of variation (day 1: AUC_τ 79.0%, C_max 84.5%; day 5: AUC_τ 82.2%, C_max 150.0%). Few AEs were reported, typically one per patient. One patient discontinued due to a serious AE (considered possibly unrelated to treatment).

Conclusions

Aclidinium/formoterol 400/12 µg twice daily was well-tolerated in patients from China with moderate-to-severe COPD. Safety findings were consistent with the known safety profile.

Clinical Trial Identifier

ClinicalTrials.gov, NCT03276078.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40268-021-00374-z.