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

A systematic review and meta-analysis of Liuzijue in stable patients with chronic obstructive pulmonary disease

BACKGROUND

To investigate the effectiveness of Liuzijue exercise on chronic obstructive pulmonary disease (COPD) in the stable phase.

METHODS

We searched six electronic bibliographic databases (PubMed, EMBASE, The Cochrane Library, Web of Science, CNKI, and Wan Fang Data) from inception to August 2018. Randomized controlled trials (RCTs) were included if they evaluated the effect of Liuzijue exercise on stable COPD. Cochrane Collaboration risk-of-bias tool (Cochrane Handbook 5.1.0) was used to assess the risk of bias of included RCTs. Meta-analysis was performed using the Review Manager software (RevMan V.5.3.5) provided by the Cochrane Collaboration. Outcomes assessed included dyspnea, exercise capacity, lung function, and quality of life.

RESULTS

Fourteen RCTs involving 920 stable COPD patients were included in this systematic review and meta-analysis. The control groups received usual care. The average number of training sessions per participant was 9.3 per week, and the average length of these training sessions was 31.6 min per week. Training duration varied from 3 to 12 months. Meta-analysis results showed that Liuzijue exercise can effectively improve patients' Modified Medical Research Council Dyspnea Scale scores (MD = - 0.73, 95% CI: - 1.13 to - 0.33, P < 0.05), 6MWD (MD = 17.78, 95% CI: 7.97 to 27.58, P < 0.05), forced expiratory volume in one second (FEV1) (MD = 0.23, 95% CI: 0.07 to 0.38, P < 0.05), the percentage of predicted values of FEV1 (FEV1%pred) (MD = 7.59, 95% CI: 2.92 to 12.26, P < 0.05), FEV1/FVC (Forced vital capacity) ratio (MD = 6.81, 95% CI: 3.22 to 10.40, P < 0.05), Quality of life: St. George's Respiratory Questionnaire total score (MD = - 9.85, 95%CI: - 13.13 to - 6.56, P < 0.05), and Chronic Obstructive Pulmonary Disease Assessment Test score (MD = - 2.29, 95%CI: - 3.27, - 1.30, P < 0.05).

CONCLUSION

Evidence from meta-analysis suggested that Liuzijue exercise could improve dyspnea, exercise endurance, lung function, and quality of life for stable COPD patients. However, owing to the methodological bias and the placebo effect of Liuzijue exercise, there is a need for further research to confirm these findings.

TRIAL REGISTRATION

PROSPERO (ID: CRD42019130973 ).

Total Antioxidant Status in Stable Chronic Obstructive Pulmonary Disease

Objective

This study evaluates the total antioxidant status (TAS) in plasma of stable chronic obstructive pulmonary disease (COPD) patients. Earlier studies of their relationship showed inconsistent findings.

Patients and Methods

We compared TAS between 90 COPD patients and 30 age- and sex-matched controls (mean age 67 ± 7.9, 87 males and 33 females) according to airway obstruction severity, gender, smoking status (current/ former/ non-smoker), smoking-dose, the number of exacerbations in the previous year, nutritional status and hypercapnia.

Results

There were no differences in pack-years between COPD and controls, neither in COPD groups. The median time from the last exacerbation was 5 months (interquartile range 3-8.3). TAS was significant higher in COPD than controls (1.68 [1.55-1.80] versus 1.59 [1.54-1.68], respectively; P = 0.03). TAS was significantly higher in COPD men than women (1.7 [1.6-1.8] versus 1.57 [1.5-1.7], respectively; P = 0.001). In COPD groups, there were no significant differences between the severity of airway obstruction and TAS. We found significant positive correlation between pack-years and TAS in all participants (Rho = 0.429, P = 0.004) and COPD patients (Rho = 0.359, P = 0.02), but not in controls. TAS was a significant predictor of COPD (β = 3.26; P = 0.04; OR = 26.01; 95% CI: 1.20 to 570.8). We failed to find significant differences between TAS and smoking status, frequency of exacerbations in the previous year, nutritional status and hypercapnia.

Conclusion

TAS was a significant predictor of COPD. TAS was a significantly higher in stable COPD than controls, higher in COPD men than women, but there was no significant correlation between TAS and the airway obstruction severity. Our results suggest that it could be appropriate to include the time from the last exacerbation in the oxidant-antioxidant balance analysis of COPD patients.

Epidemiology and risk factors of chronic obstructive pulmonary disease in Suzhou: a population-based cross-sectional study

Background

The prevalence of chronic obstructive pulmonary disease (COPD) in Suzhou remains still unknown. The aim of this study was to quantify the disease burden and assess the risk factors of COPD.

Methods

This was a population-based, cross-sectional study of adults aged 40 years and older in Suzhou. A total of 4,864 adults were identified from June 2018 to December 2018 and 4,725 adults were finally recruited. Subjects underwent post-bronchodilator spirometry and were diagnosed according to the 2018 Global Initiative for Chronic Obstructive Lung Disease (GOLD).

Results

The data from 4,725 adults were ultimately included in the final analysis. The overall prevalence of COPD in subjects aged 40 and older was 12.4%, while it was 12.3% in men and 12.5% in women. Risk factors identified by multivariable logistic analysis were age (P<0.05, OR =2.29, 95% CI, 1.83–2.88) and underweight (BMI <18.5 kg/m²) (P<0.05, OR =1.57, 95% CI, 1.01–2.44). COPD patients also displayed weaker grip strength (P<0.001). Approximately half (50.7%) the COPD patients were asymptomatic, and compared with asymptomatic COPD patients, symptomatic COPD patients were older (69.5 vs. 67.2, P<0.05), smoked more frequently (12.1 vs. 7.1 pack year, P<0.05), had a more severe GOLD stage (stage I 27.0% vs. 39.4%, stage II 50.2% vs. 46.8%, stage III 17.0% vs. 11.1%, stage IV 5.8% vs. 2.7%, P<0.05), and a worse lung function index (FEV₁, FVC, PEF, FEF₂₅, FEF₅₀, FEF₇₅, FEF₂₅₇₅) (P<0.05).

Conclusions

COPD was found to be highly prevalent in adults aged 40 years and older in Suzhou. Age and underweight were major risk factors of COPD. Half of the COPD patients were asymptomatic, and displayed decreased lung function upon the onset of respiratory symptoms. Therefore, spirometry screening is essential for the early detection and management of COPD.

Prevalence of Chronic Obstructive Pulmonary Disease and its Associated Factors in Nepal: Findings from a Community-based Household Survey

Background

Despite chronic obstructive pulmonary disease (COPD) being the commonest non-communicable disease in Nepal, there is limited research evidence estimating the spirometry-based burden of COPD. This study aims to estimate the prevalence of COPD and its correlates through a community-based survey in Pokhara Metropolitan City, a semi-urban area of Western Nepal.

Methods

A cross-sectional household survey was conducted among 1459 adults ≥40 years. COPD was defined according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria as a post-bronchodilator ratio of forced expiratory volume in 1st second (FEV₁) to forced vital capacity (FVC) <0.70 with the presence of symptoms. COPD was also defined by the lower limit of normal (LLN) threshold – FEV₁/FVC < LLN cut-off values with the presence of symptoms. Study participants were interviewed about sociodemographic and behavioural characteristics and respiratory symptoms. Descriptive statistics and logistic regression analysis were applied.

Results

Spirometry reports were acceptable in 1438 participants. The mean age of the participants was 55 (±10) years, and, 54% were female. The prevalence of GOLD-defined COPD was 8.5% (95% CI: 7.1–10.0) and based on the LLN threshold of 5.4% (95% CI: 4.2–6.6). The multivariate logistic regression showed that increasing age, low body mass index, illiterate, current or former smoker, and biomass fuel smoke increased the odds of COPD in both the definitions.

Conclusion

COPD is highly prevalent at community level and often underdiagnosed. Strategies aiming at early diagnosis and treatment of COPD, especially for the elderly, illiterate, and reducing exposure to smoking and biomass fuel smoke and childhood lung infection could be effective.

Clinical Characteristics of Chronic Obstructive Pulmonary Disease in Female Patients: Findings from a KOCOSS Cohort

PURPOSE

The prevalence of chronic obstructive pulmonary disease (COPD) in females has increased, changing the concept of COPD as a disease mostly limited to males. In this study, the clinical characteristics of COPD in females were investigated.

PATIENTS AND METHODS

The study was based on a multicenter cohort of COPD patients recruited from 54 medical centers in South Korea. Sex-based differences in general characteristics, exposure risk factors, depression scores, results of pulmonary function tests, COPD exacerbation, symptom scores, and radiologic findings were evaluated. Sex-related differences in the annual FEV1 change over 5 years were analyzed in a linear mixed model.

RESULTS

Of the 2515 patients enrolled in this study, 8.1% were female. Female patients who had a higher BMI and a lower level of education were less likely to be smokers, were more exposed to passive smoking/biomass, and were more depressed compared to males. The rates of bronchiectasis, previous childhood respiratory infection, and asthma were higher in females. Female patients also had more symptoms and a poorer exercise capacity than males, but no significant differences were observed in terms of exacerbations. Radiologic findings revealed that male patients had worse emphysema, and female patients had worse bronchiectasis, as determined based on chest X-ray and computed tomography findings. On pulmonary function tests, female patients had less obstruction and less annual FEV1 loss over 5 years.

CONCLUSION

This study revealed differences in the clinical parameters between male and female patients with COPD, including general characteristics, disease characteristics, and clinical outcomes.

Efficacy and safety of glycopyrrolate/formoterol fumarate metered dose inhaler delivered using co-suspension delivery technology in Japanese patients with moderate-to-very severe chronic obstructive pulmonary disease

BACKGROUND

PINNACLE-4 evaluated the efficacy and safety of the long-acting muscarinic antagonist/long-acting β₂-agonist fixed-dose combination glycopyrrolate/formoterol fumarate metered dose inhaler (GFF MDI) in patients from Asia, Europe, and the USA with moderate-to-very severe chronic obstructive pulmonary disease (COPD). This pre-specified analysis included Japanese patients in PINNACLE-4.

METHODS

In this double-blind randomized study (NCT02343458), patients received GFF MDI (18/9.6 μg), glycopyrrolate (GP) MDI (18 μg), formoterol fumarate (FF) MDI (9.6 μg), or placebo MDI twice daily for 24 weeks. The primary endpoint was change from baseline in morning pre-dose trough forced expiratory volume in 1 s (FEV₁) over Weeks 12-24. Secondary lung function endpoints, patient-reported outcomes, and safety were assessed. The Japanese subpopulation (n = 150) analyses were exploratory.

RESULTS

GFF MDI improved change from baseline in morning pre-dose trough FEV₁ over Weeks 12-24 versus GP MDI, FF MDI, and placebo MDI (least squares mean [LSM] differences [95% confidence interval]: 69 [8-131], 60 [-1 to 121], and 275 [180-370] mL, respectively). GFF MDI numerically improved Transition Dyspnea Index focal score and change from baseline in St George's Respiratory Questionnaire total score versus placebo MDI (LSM differences 0.19 and -3.78, respectively). Treatment-related adverse events occurred in ≤4.5% of patients in any treatment group.

CONCLUSIONS

GFF MDI improved lung function versus monocomponents and placebo MDI in the Japan subpopulation of PINNACLE-4. The efficacy and safety results were generally consistent with those of the global study population, supporting the use of GFF MDI in Japanese patients with moderate-to-very severe COPD.

The long-term outcomes of tobacco control strategies based on the cognitive intervention for smoking cessation in COPD patients

OBJECTIVE

To evaluate the long-term efficacy of tobacco control strategies based on cognitive intervention for smoking cessation in chronic obstructive pulmonary disease (COPD) patients, and to provide basis for clinical practice.

MATERIALS AND METHODS

102 COPD patients with a long-term history of smoking from the outpatient clinic were recruited in the study. These smokers were randomly divided into intervention group and control group. The intervention group received a cognitive intervention containing individual consultation, telephone follow-ups and self-help materials, etc. The prevalence of quitting smoking, acute exacerbation (AE), lung function and survival were compared in the groups in 10 years.

RESULTS

There were significant differences between the intervention group and the control group in the rate of persistent quitting smoking in half a year (17.6% vs 3.9%) (P < 0.05), the rate of quitting smoking at the 6th month (58.8% vs 33.3%) (P < 0.05). After 3 months (P < 0.01) and 6 months (P < 0.01), the difference in body weight between the intervention group and the control group was statistically significant. Intervention-group patients had fewer AE per year (P < 0.01) and higher FEV1/FVC ratio (P < 0.01) after 5-year and 10-year follow-up. Besides, the FEV1% predicted in the intervention patients was higher than that in control group after 10-year follow-up. The ages of patients in the death group were greater than those in the survival group. Death-group patients had longer smoking times, higher smoking index, and later onset of COPD symptoms. Death-group patients had lower FEV1% predicted (P < 0.05) and FEV1/FVC ratio (P < 0.01). During 10-year follow-up, 30 patient deaths were recorded (the control group: n = 48; 19 deaths, and intervention group: n = 46; 11 deaths), and patients in the control group had lower survival than those in the intervention group. (P < 0.05).

CONCLUSION

The method of quitting smoking based on cognitive intervention is an effective way for COPD patients to quit smoking successfully. Quitting smoking can slower deterioration in lung function and improve the survival of COPD patients.

CLINICAL TRIAL REGISTRATION NUMBER

ChiCTR2000031239 (Chinese clinical trial registry).

High-dose N-acetylcysteine for long-term, regular treatment of early-stage chronic obstructive pulmonary disease (GOLD I-II): study protocol for a multicenter, double-blinded, parallel-group, randomized controlled trial in China

INTRODUCTION

The presence of increased oxidative stress and airway inflammation has been proven in subjects with chronic obstructive pulmonary disease (COPD). Several studies have demonstrated that drugs with antioxidant and anti-inflammatory properties such as N-acetylcysteine (NAC) can reduce the rate of exacerbations in patients with COPD. However, the beneficial effects of NAC in early-stage COPD are minimally discussed. We are investigating whether high-dose NAC has therapeutic effects in Chinese patients with early-stage COPD.

METHOD AND ANALYSIS

A randomized, double-blinded, placebo-controlled, parallel-group, multicenter clinical trial is evaluating the efficacy and safety of NAC for the long-term treatment of patients with early-stage COPD at 24 centers in China. Subjects aged 40-80 years and recruited by physicians or researchers with special training will be randomized to either NAC 600 mg twice daily group or matching placebo group for 2 years. Measurements will include forced expiratory volume in 1 s (FEV1), the number of COPD exacerbations, health-related quality, and pharmacoeconomic analysis.

DISCUSSION

Currently, there are no randomized controlled trials with high-dose N-acetylcysteine (600 mg twice daily) for patients with mild-to-moderate COPD (GOLD I-II). We designed this multicenter randomized controlled trial (RCT) to assess the effectiveness, safety, and cost-effectiveness of long-term treatment with high-dose N-acetylcysteine. The results of this trial may guide clinical practice and change the standard of early COPD management.

TRIAL REGISTRATION

Chinese Clinical Trial Registry ChiCTR-IIR-17012604 . Registered on 07 September 2017.

Construction of Potential miRNA-mRNA Regulatory Network in COPD Plasma by Bioinformatics Analysis

Background

Chronic obstructive pulmonary disease (COPD) has become a major cause of morbidity and mortality worldwide. Increasing evidence indicates that aberrantly expressed microRNAs (miRNAs) are involved in the pathogenesis of COPD. However, an integrative exploration of miRNA–mRNA regulatory network in COPD plasma remains lacking.

Methods

The microarray datasets GSE24709, GSE61741, and GSE31568 were downloaded from the GEO database and analyzed using GEO2R tool to identify differentially expressed miRNAs (DEMs) between COPD and normal plasma. The consistently changing miRNAs in the three datasets were screened out as candidate DEMs. Potential upstream transcription factors and downstream target genes of candidate DEMs were predicted by FunRich and miRNet, respectively. Next, GO annotation and KEGG pathway enrichment analysis for target genes were performed using DAVID. Then, PPI and DEM-hub gene network were constructed using the STRING database and Cytoscape software. Finally, GSE56768 was used to evaluate the hub gene expressions.

Results

A total of nine (six upregulated and three downregulated) DEMs were screened out in the above three datasets. SP1 was predicted to potentially regulate most of the downregulated DEMs, while YY1 and E2F1 could regulate both upregulated and downregulated DEMs. 1139 target genes were then predicted, including 596 upregulated DEM target genes and 543 downregulated DEM target genes. Target genes of DEMs were mainly enriched in PI3K/Akt signaling pathway, mTOR signaling pathway, and autophagy. Through the DEM-hub gene network construction, most of the hub genes were found to be potentially modulated by miR-497-5p, miR-130b-5p, and miR-126-5p. Among the top 12 hub genes, MYC and FOXO1 expressions were consistent with that in the GSE56768 dataset.

Conclusion

In the study, potential miRNA–mRNA regulatory network was firstly constructed in COPD plasma, which may provide a new insight into the pathogenesis and treatment of COPD.

Value of metalloproteinases in predicting COPD in heavy urban smokers

Background

Emphysema in asymptomatic heavy smokers can be detected during CT-scan screening for lung cancer. Metalloproteinases (MMPs) have been found to play a role in the pathogenesis of chronic obstructive pulmonary disease and to possibly serve as biomarkers for emphysema.

Methods

The NYU Lung Cancer Biomarker Center enrolled study subjects over 50 years of age with lung cancer risk factors from January 1, 2010, to December 31, 2015. These subjects received chest multi-detector computed tomography, spirometry, and provided serum for immunoassays for metalloproteinases (MMP) -1, -2, -7, -9, -10 and tissue inhibitor of metalloproteinases (TIMP) -1 and -2.

Results

Three hundred sixteen study subjects were enrolled. Of the 222 patients who met the inclusion criteria, 46% had emphysema. Smokers with emphysema had increased pack-years of smoking compared to smokers without emphysema (51 ± 24 pack-years (mean ± sd) versus 37 ± 20; p < 0.0001). Smokers with emphysema also had lower FEV₁/FVC percent compared to smokers without emphysema (68 ± 11 (mean ± sd) versus 75 ± 8; p < 0.0001). Increased age and pack-years of smoking were associated with increased odds of emphysema. None of the metalloproteinases or tissue inhibitors of metalloproteinases were useful to predict the presence of emphysema in smokers.

Conclusion

Emphysema was detected by CT in almost half of heavy urban smokers. Serum MMP levels provided minimal additional information to improve the detection of mild emphysema among smokers given their clinical characteristics (age, pack-years, and FEV₁/FVC ratio).

Validation of the brief international classification of functioning, disability, and health core set for obstructive pulmonary disease in the Chinese context

In order to determine the validity of the International Classification of Functioning, Disability, and Health brief Core Set for Obstructive Pulmonary Disease (ICF-OPD) for the assessment of functioning and environmental factors in Chinese chronic OPD (COPD) patients, we conducted a cross-sectional study with a convenience sample of 100 COPD patients. Data were collected using common questionnaires for COPD patients (Modified British Medical Research Council Questionnaire, COPD Assessment Test, St George’s Respiratory Questionnaire (SGRQ)), the Brief ICF Core Set for OPD, and the comprehensive ICF checklist. All except one category of the Brief ICF-OPD Core Set were confirmed in our evaluation of its content validity, but there is a high prevalence of problems in 8 categories that were not considered in the Brief ICF-OPD Core Set. The functioning-related components of the Brief ICF-OPD Core Set largely performed similarly to SGRQ in terms of differentiating between patients with different disease severity. Moreover, high correlations between the Brief ICF-OPD Core Set overall score and component scores with the respective SGRQ scales and moderate correlations between ICF-OPD Core Set overall score and component scores and lung function parameters. This study largely confirmed content, known group, and convergent validity of the ICF-OPD.

Different Characteristics of Ex-Smokers and Current Smokers with COPD: A Cross-Sectional Study in China

PURPOSE

Chronic obstructive pulmonary disease (COPD), usually caused by tobacco smoking, is increased in China. Smoking cessation is the first step in COPD management. Data on predictors of smoking cessation are sparse in COPD patients in China. We aim to find the differences in the clinical characteristics between ex-smokers and current smokers with COPD to determine the factors related to smoking cessation.

PATIENTS AND METHODS

From outpatient departments of 12 hospitals in Hunan and Guangxi provinces, a total of 4331 patients were included. Information on demographic and sociological data, lung function, and modified Medical Research Council (mMRC) dyspnea scale scores were recorded. Patients were divided into an ex-smokers group and a current smokers group based on whether they gave up smoking. A logistic regression analysis was performed to analyze the factors associated with smoking cessation.

RESULTS

Of the total, the mean age was 62.9±8.5 years, and 47.3% were ex-smokers. Compared with the current smokers, the ex-smokers were older, and had heavier dyspnea, more severe airflow limitation, fewer pack-years, shorter smoking duration, and a higher proportion of Global Initiative for Chronic Obstructive Lung Disease (GOLD) groups C and D. The logistic regression model showed that smoking cessation was negatively correlated with widowhood, years of smoking, and forced expiratory volume in 1 second (FEV1), but was positively correlated with age, education level, amount smoked, mMRC score, GOLD grades, and GOLD groups.

CONCLUSION

Among patients with COPD, more than half still smoked. In the group of patients who quit smoking, many of them quit rather late in age after they had significant symptoms. Several predictors of smoking cessation were identified, indicating that ex-smokers differ substantially from continuing smokers. This should be taken into account in smoking-cessation interventions.

Biofeedback flutter device for managing the symptoms of patients with COPD

BACKGROUND

Flutter is a device used in removing excess lung secretions. The conventional flutter lacks a biofeedback component to facilitate optimal use by the patients.

OBJECTIVE

The current research aims to compare the effects of biofeedback flutter devices with the conventional flutter in managing the symptoms of patients with chronic obstructive pulmonary diseases.

METHODS

One hundred and sixty-eight participants were randomly allocated into four groups: Group A (conventional), Group B (visual biofeedback), Group C (auditory biofeedback) and Group D (visual and auditory biofeedback). All groups were treated five days for 20 minutes. Outcome measures included wet sputum weight [during intervention (T1) and 1 hour after intervention (T2)], oxygen saturation and dyspnea score (before and after intervention) on all days.

RESULTS

The wet sputum expectorated (T2) by Group B was significantly higher than Group A (P< 0.001), Group C (P< 0.001) and Group D (P< 0.05). The dyspnea score for Group B (P< 0.05), Group C (P< 0.05) and Group D (P< 0.05) was significantly lower than Group A. The post-intervention oxygen saturation level was higher in Group D followed by Groups B, C and A.

CONCLUSION

The use of biofeedback flutter is effective in the removal of secretion, reducing dyspnea and improving oxygen saturation when compared to conventional flutter.

Risk factors for predicting mortality in elderly patients with COVID-19: A review of clinical data in China

While elderly patients are at high risk of fatality, research concerning COVID-19 has largely been done on clarifying the clinical features. As such, the present work aims to identify risk factors for mortality in elderly patients with COVID-19. Given that single-centre studies are less likely informative as elderly remains a minority in the total Chinese population, the present study reviewed the clinical data of geriatric COVID-19 patients gathered from different sources in the public domain. Based on the data of 154 individuals from 26 provinces, age remained a key mortality risk factor among geriatric patients of different ages. While dyspnoea and chest pain/discomfort were more commonly seen in deceased patients as they represented severe pneumonia, fever was more prominent in surviving patients. This was likely due to the lower baseline body temperature observed in elderly which translated to a lower maximum temperature of fever. However, lowering the threshold temperature for fever is not recommended in surveillance. Instead, baseline body temperature measured on a regular basis should be used to define the threshold temperature for fever. Against mixed results, more research should be done on identifying comorbidities associated with mortality in geriatric patients.

Trends in Hospitalization Expenditures for Acute Exacerbations of COPD in Beijing from 2009 to 2017

Background

Chronic obstructive pulmonary disease (COPD) is the cause of substantial economic and social burden. We investigated trends in hospitalizations for acute exacerbation of COPD in Beijing, China, from 2009 to 2017.

Patients and Methods

Investigations were conducted using data from the discharge records of inpatients that were given a primary diagnosis of acute exacerbation of COPD. The dataset was a retrospective review of information collected from electronic medical records and included 315,116 admissions (159,368 patients). Descriptive analyses and multivariate regressions were used to investigate trends in per admission and per capita expenditures, as well as other potential contributing factors.

Results

The mean per admission expenditures increased from 19,760 CNY ($2893, based on USD/CNY=6.8310) in 2009 to 20,118 CNY ($2980) in 2017 (a growth rate of 0.11%). However, the per capita expenditures increased from 23,716 CNY ($3472) in 2009 to 31,000 CNY ($4538) in 2017 (a growth rate of 1.7%). In terms of per admission expenditures, drug costs accounted for 52.9% of the total expenditures in 2009 and dropped to 39.4% in 2017 (P trend < 0.001). The mean length of stay (LOS) decreased from 16.0 days to 13.5 days (P trend < 0·001). Age, gender, COPD type, LOS, and hospital level were all associated with per admission and per capita expenditures.

Interpretation

Relatively stable per admission expenditures along with the decline in drug costs and LOS reflect the effectiveness of cost containment on some indicators in China’s health care reform. However, the increase in hospitalization expenditures per capita calls for better policies for controlling hospitalizations, especially multiple admissions.

Long-Term Trends in Hospitalization and Outcomes in Adult Patients with Exacerbation of Chronic Obstructive Pulmonary Disease in Beijing, China, from 2008 to 2017

Background and Objective

Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality worldwide. We aimed to evaluate the temporal trends in hospitalization and mortality from acute exacerbation of COPD (AECOPD) and the associated financial costs over a 10-year period in Beijing, China.

Methods

Hospital admission records from 2008 to 2017 for all patients aged ≥20 years with a primary discharge diagnosis of AECOPD were retrieved from the Beijing Public Health Information Center Database. Joinpoint regression was used to analyze trends and calculate the annual percentage change (APC) and average annual percent change (AAPC) for AECOPD hospitalization and mortality.

Results

A total of 337,802 AECOPD cases were recorded from 2008 to 2017. An inverse U-shaped trend in the AECOPD hospitalization rate was observed, showing an increase from 150.2 per 100,000 inhabitants in 2008 to 218.7 per 100,000 inhabitants in 2014 (APC: 5.5%, 95% CI: 2.9–8.2), before declining to 161.13 per 100,000 inhabitants in 2017 (APC: −9.7%, 95% CI: −16.0 to-2.9). In-hospital mortality from AECOPD decreased significantly from 3.91% to 2.21% (AAPC: −11.4%, 95% CI: −15.5 to−7.0). A decline in the median length of hospital stay from 13.0 days in 2008 to 12.0 days in 2017 (P_trend < 0.001) was accompanied by a decrease in the use of mechanical ventilation from 2012 to 2017 (P_trend < 0.001). However, the total hospitalization cost per case increased from 15953.5 yuan (USD $2281.4) to 19874.5 yuan ($2842.1) during the same period.

Conclusion

AECOPD remains a heavy burden on the health care system in Beijing. Strategies to better manage COPD and reduce hospitalizations from AECOPD are needed.

The acute effects of cigarette smoke exposure on muscle fiber type dynamics in rats

Reduced exercise capacity is common in people with chronic obstructive pulmonary diseases (COPD) and chronic smokers and is suggested to be related to skeletal muscle dysfunction. Previous studies using human muscle biopsies have shown fiber-type shifting in chronic smokers particularly those with COPD. These results, however, are confounded with aging effects because people with COPD tend to be older. In the present study, we implemented an acute 7-day cigarette smoke-exposed model using Sprague-Dawley rats to evaluate early effects of cigarette smoking on soleus muscles. Rats (n = 5 per group) were randomly assigned to either a sham air (SA) or cigarette smoking (CS) groups of three different concentrations of total particulate matters (TPM) (CS_TPM2.5, CS_TPM5, CS_TPM10). Significantly lower percentages of type I and higher type IIa fiber were detected in the soleus muscle in CS groups when compared with SA group. Of these, only CS_TMP10 group exhibited significantly lower citrate synthase activity and higher muscle tumor necrosis factor-α level than that of SA group. Tumor necrosis factor-α level was correlated with the percentage of type I and IIa fibers. However, no significant between-group differences were found in fiber cross-sectional area, physical activities, or lung function assessments. In conclusion, acute smoking may directly trigger the onset of glycolytic fiber type shift in skeletal muscle independent of aging.

Susceptibility of individuals with chronic obstructive pulmonary disease to air pollution exposure in Beijing, China: A case-control panel study (COPDB)

Exposure to air pollution is one of the major risk factors contributing to the occurrence and development of chronic obstructive pulmonary disease (COPD). However, few studies have investigated the susceptibility of patients with COPD to air pollution. Here, we provided a study protocol. A panel study of a total of 480 samples to compare the response to air pollution exposure between 60 patients with COPD and 60 healthy control subjects has been performed in Beijing (the COPDB study) since May 2016. The health assessment and exposure evaluation methods used in this COPDB study are summarized here. Throat, exhaled breath and condensate, urine, serum, plasma, and blood samples, as well as cardiopulmonary function indexes were repeatedly collected over four visits. Indicators of inflammation, oxidative stress, infection, metabolic changes, and genetic differences were then analyzed. Personal and ambient levels of fine particles and their components, as well as gaseous pollutants were monitored during the follow-up period. Linear mixed-effects models were used to evaluate the associations between changes in biomarkers and exposure to air pollution in both patients with COPD and healthy control subjects. Based on the COPDB study, the susceptibility of COPD patients and underlying mechanisms, involving difference in inflammatory, infection, metabolic, and genetic response to different air pollutants, were investigated. Our preliminary result shows that air pollution-associated changes in heart rate were higher in COPD patients than the healthy controls. More investigations of the underlying mechanisms of the susceptibility are ongoing. This study has been registered in ChiCTR with the number of ChiCTR1900023692.

Efficacy and Safety of Once-Daily Inhaled Umeclidinium in Asian Patients with COPD: Results from a Randomized, Placebo-Controlled Study

Purpose

Previous studies demonstrating efficacy and safety of once-daily umeclidinium (UMEC) in patients with chronic obstructive pulmonary disease (COPD) have included few Asian patients. This study evaluated efficacy and safety of UMEC 62.5 mcg versus placebo in Asian patients with COPD.

Patients and Methods

A Phase III, randomized, double-blind, parallel-group study. Patients (aged ≥40 years with COPD, pre-, and post-albuterol forced expiratory volume in 1 s [FEV1]/forced vital capacity ratio <0.70 and low risk of exacerbations) were randomized 2:1 to once-daily UMEC 62.5 mcg or placebo via the ELLIPTA inhaler for 24 weeks. Primary endpoint was change from baseline (CFB) in trough FEV1 on Day 169. Secondary endpoints were weighted mean FEV1 over 0-6 hrs post-dose on Day 1 and CFB in Transition Dyspnea Index (TDI) focal score on Day 168.

Results

A total of 306 patients were included in the modified intent-to-treat population (UMEC: 205; placebo: 101). UMEC versus placebo provided a statistically significant improvement in least squares (LS) mean trough FEV1 between baseline and Day 169 (154 mL [95% confidence interval (CI): 113, 194]; p<0.001). A clinically meaningful difference of 125 mL in favor of UMEC (95% CI: 103, 147; p<0.001) was also seen in LS weighted mean FEV1 0-6 hrs post-dose on Day 1. A LS mean treatment difference in TDI focal score of 0.9 units in favor of UMEC was seen on Day 168 (95% CI: 0.3, 1.5; p=0.004). Incidence of on-treatment adverse events (AEs) was lower in the placebo (55%) versus UMEC arm (60%); non-fatal serious AEs, drug-related AEs, and AEs leading to withdrawal were similar with UMEC and placebo.

Conclusion

Once-daily UMEC 62.5 mcg resulted in statistically significant and clinically meaningful improvements in lung function and dyspnea, compared with placebo, in Asian patients with COPD, with no new safety concerns observed.

The correlation between CYP4F2 variants and chronic obstructive pulmonary disease risk in Hainan Han population

Background

Chronic obstructive pulmonary disease (COPD) is a complex pulmonary disease. Cytochrome P450 family 4 subfamily F member 2 (CYP4F2) belongs to cytochrome P450 superfamily of enzymes responsible for metabolism, its single nucleotide polymorphisms (SNPs) were reported to be involved in metabolism in the development of many diseases. The study aimed to assess the relation between CYP4F2 SNPs and COPD risk in the Hainan Han population.

Method

We genotyped five SNPs in CYP4F2 in 313 cases and 508 controls by Agena MassARRAY assay. The association between CYP4F2 SNPs and COPD risk were assessed by χ² test and genetic models. Besides, logistic regression analysis was introduced into the calculation for odds ratio (OR) and 95% confidence intervals (CIs).

Results

Allele model analysis indicated that rs3093203 A was significantly correlated with an increased risk of COPD. Also, rs3093193 G and rs3093110 G were associated with a reduced COPD risk. In the genetic models, we found that rs3093203 was related to an increased COPD risk, while rs3093193 and rs3093110 were related to a reduced risk of COPD. After gender stratification, rs3093203, rs3093193 and rs3093110 showed the association with COPD risk in males. With smoking stratification, rs3093144 was significantly associated with an increased risk of COPD in smokers. CYP4F2 SNPs were significantly associated with COPD risk.

Conclusions

Our findings illustrated potential associations between CYP4F2 polymorphisms and COPD risk. However, large-scale and well-designed studies are needed to determine conclusively the association between the CYP4F2 SNPs and COPD risk.

Association between adiposity measures and COPD risk in Chinese adults

Bodyweight and fat distribution may be related to COPD risk. Limited prospective evidence linked COPD to abdominal adiposity. We investigated the association of body mass index (BMI) and measures of abdominal adiposity with COPD risk in a prospective cohort study.The China Kadoorie Biobank recruited participants aged 30-79 years from 10 areas across China. Anthropometric indexes were objectively measured at the baseline survey during 2004-2008. After exclusion of participants with prevalent COPD and major chronic diseases, 452 259 participants were included and followed-up until the end of 2016. We used Cox models to estimate adjusted hazard ratios relating adiposity to risk of COPD hospitalisation or death.Over an average of 10.1 years of follow-up, 10 739 COPD hospitalisation events and deaths were reported. Compared with subjects with normal BMI (18.5-<24.0 kg·m-2), underweight (BMI <18.5 kg·m-2) individuals had increased risk of COPD, with adjusted hazard ratio 1.78 (95% CI 1.66-1.89). Overweight (BMI 24.0-<28.0 kg·m-2) and obesity (BMI ≥28.0 kg·m-2) were not associated with an increased risk after adjustment for waist circumference. A higher waist circumference (≥85 cm for males and ≥80 cm for females) was positively associated with COPD risk after adjustment for BMI. Additionally, waist-to-hip ratio and waist-to-height ratio were positively related to COPD risk.Abdominal adiposity and underweight were risk factors for COPD in Chinese adults. Both BMI and measures of abdominal adiposity should be considered in the prevention of COPD.

COPD as an independent risk factor for osteoporosis and fractures

Fractures are common in individuals with COPD and occur at higher bone mass values than expected. COPD appears to be an important risk factor for bone fragility.

INTRODUCTION

Patients with chronic obstructive pulmonary disease (COPD) have an increased risk of osteoporosis and fractures, but screening and prophylactic measures to prevent both disorders are often neglected in this population. This case-control study assessed the prevalence of osteopenia, osteoporosis, and fractures in patients with COPD, and identified potential risk factors for fractures in this population.

METHODS

Overall, 91 patients with COPD (COPD group; COPDG) and 81 age- and sex-matched controls (control group; CG) were assessed with bone mineral density (BMD), thoracic/lumbar spine radiographs, and serum PTH and 25-hydroxyvitamin D (25[OH]D) levels. The occurrence of prior fractures was retrieved from clinical history.

RESULTS

The prevalence of total fractures in the COPDG was 57.1% (odds of fracture 4.7 times greater compared with the CG), and the femoral neck T-score emerged as the best predictor of fractures. Compared with the CG, the COPDG had lower spine and femoral BMD (p ≤ 0.01) and 25(OH)D levels (p = 0.01) and 2.6 times greater odds of osteoporosis. Among men, vertebral fractures were more prevalent in the COPDG versus CG (25.9% vs. 6.5%, respectively, p = 0.01). The odds of fracture increased with femoral neck T-scores ≤ - 2.7 in the CG and ≤ - 0.6 in the COPDG.

CONCLUSION

These results add robust evidence to an increased odds of osteoporosis and fractures in COPD. Fractures in the COPDG occurred at higher BMD values than expected, suggesting that COPD may be an independent marker of fracture risk, reinforcing a need for regular osteoporosis screening with BMD measurement and prophylaxis of fractures in patients with this disorder.

Comparison and development of machine learning tools for the prediction of chronic obstructive pulmonary disease in the Chinese population

Background

Chronic obstructive pulmonary disease (COPD) is a major public health problem and cause of mortality worldwide. However, COPD in the early stage is usually not recognized and diagnosed. It is necessary to establish a risk model to predict COPD development.

Methods

A total of 441 COPD patients and 192 control subjects were recruited, and 101 single-nucleotide polymorphisms (SNPs) were determined using the MassArray assay. With 5 clinical features as well as SNPs, 6 predictive models were established and evaluated in the training set and test set by the confusion matrix AU-ROC, AU-PRC, sensitivity (recall), specificity, accuracy, F1 score, MCC, PPV (precision) and NPV. The selected features were ranked.

Results

Nine SNPs were significantly associated with COPD. Among them, 6 SNPs (rs1007052, OR = 1.671, P = 0.010; rs2910164, OR = 1.416, P < 0.037; rs473892, OR = 1.473, P < 0.044; rs161976, OR = 1.594, P < 0.044; rs159497, OR = 1.445, P < 0.045; and rs9296092, OR = 1.832, P < 0.045) were risk factors for COPD, while 3 SNPs (rs8192288, OR = 0.593, P < 0.015; rs20541, OR = 0.669, P < 0.018; and rs12922394, OR = 0.651, P < 0.022) were protective factors for COPD development. In the training set, KNN, LR, SVM, DT and XGboost obtained AU-ROC values above 0.82 and AU-PRC values above 0.92. Among these models, XGboost obtained the highest AU-ROC (0.94), AU-PRC (0.97), accuracy (0.91), precision (0.95), F1 score (0.94), MCC (0.77) and specificity (0.85), while MLP obtained the highest sensitivity (recall) (0.99) and NPV (0.87). In the validation set, KNN, LR and XGboost obtained AU-ROC and AU-PRC values above 0.80 and 0.85, respectively. KNN had the highest precision (0.82), both KNN and LR obtained the same highest accuracy (0.81), and KNN and LR had the same highest F1 score (0.86). Both DT and MLP obtained sensitivity (recall) and NPV values above 0.94 and 0.84, respectively. In the feature importance analyses, we identified that AQCI, age, and BMI had the greatest impact on the predictive abilities of the models, while SNPs, sex and smoking were less important.

Conclusions

The KNN, LR and XGboost models showed excellent overall predictive power, and the use of machine learning tools combining both clinical and SNP features was suitable for predicting the risk of COPD development.

The Occupational Burden of Nonmalignant Respiratory Diseases. An Official American Thoracic Society and European Respiratory Society Statement

Rationale: Workplace inhalational hazards remain common worldwide, even though they are ameliorable. Previous American Thoracic Society documents have assessed the contribution of workplace exposures to asthma and chronic obstructive pulmonary disease on a population level, but not to other chronic respiratory diseases. The goal of this document is to report an in-depth literature review and data synthesis of the occupational contribution to the burden of the major nonmalignant respiratory diseases, including airway diseases; interstitial fibrosis; hypersensitivity pneumonitis; other noninfectious granulomatous lung diseases, including sarcoidosis; and selected respiratory infections. Methods: Relevant literature was identified for each respiratory condition. The occupational population attributable fraction (PAF) was estimated for those conditions for which there were sufficient population-based studies to allow pooled estimates. For the other conditions, the occupational burden of disease was estimated on the basis of attribution in case series, incidence rate ratios, or attributable fraction within an exposed group. Results: Workplace exposures contribute substantially to the burden of multiple chronic respiratory diseases, including asthma (PAF, 16%); chronic obstructive pulmonary disease (PAF, 14%); chronic bronchitis (PAF, 13%); idiopathic pulmonary fibrosis (PAF, 26%); hypersensitivity pneumonitis (occupational burden, 19%); other granulomatous diseases, including sarcoidosis (occupational burden, 30%); pulmonary alveolar proteinosis (occupational burden, 29%); tuberculosis (occupational burden, 2.3% in silica-exposed workers and 1% in healthcare workers); and community-acquired pneumonia in working-age adults (PAF, 10%). Conclusions: Workplace exposures contribute to the burden of disease across a range of nonmalignant lung conditions in adults (in addition to the 100% burden for the classic occupational pneumoconioses). This burden has important clinical, research, and policy implications. There is a pressing need to improve clinical recognition and public health awareness of the contribution of occupational factors across a range of nonmalignant respiratory diseases.

Geographical Disparity and Associated Factors of COPD Prevalence in China: A Spatial Analysis of National Cross-Sectional Study

Purpose

COPD prevalence has rapidly increased in China, but the geographical disparities in COPD prevalence remain largely unknown. This study aimed to assess city-level disparities in COPD prevalence and identify the relative importance of COPD related risk factors in mainland China.

Patients and Methods

A nationwide cross-sectional study of COPD recruited 66,752 adults across the mainland China between 2014 and 2015. Patients with COPD were ascertained by a post-bronchodilator pulmonary function test. We estimated the city-specific prevalence of COPD by spatial kriging interpolation method. We detected spatial clusters with a significantly higher prevalence of COPD by spatial scan statistics. We determined the relative importance of COPD associated risk factors by a nonparametric and nonlinear classification and regression tree (CART) model.

Results

The three spatial clusters with the highest prevalence of COPD were located in parts of Sichuan, Gansu, and Shaanxi, etc. (relative risks (RRs)) ranging from 1.55 (95% CI 1.55-1.56) to 1.33 (95% CI 1.33-1.33)). CART showed that advanced age (≥60 years) was the most important factor associated with COPD in the overall population, followed by smoking. We estimated that there were about 28.5 million potentially avoidable cases of COPD among people aged 40 or older if they never smoked. PM2.5 was an important associated risk factor for COPD in the north, northeast, and southwest of China. After adjusting for age and smoking, the spatial cluster with the highest prevalence shifted to most of Sichuan, Gansu, Qinghai, and Ningxia, etc. (RR 1.65 (95% CI 1.63-1.67)).

Conclusion

The spatial clusters of COPD at the city level and regionally varied important risk factors for COPD would help develop tailored interventions for COPD in China. After adjusting for the main risk factors, the spatial clusters of COPD shifted, indicating that there would be other potential risk factors for the remaining clusters which call for further studies.

An epidemiologic study of physician-diagnosed chronic obstructive pulmonary disease in the Turkish population: COPDTURKEY-1

Background/aim

Chronic obstructive pulmonary disease (COPD) is a common disease characterized by persistent airflow limitation and respiratory symptoms. It is a leading cause of morbidity and mortality all over the world. Our data on COPD in Turkey are limited. This study was intended to examine the epidemiologic characteristics of COPD in the Turkish population, between 2012 and 2016.

Materials and methods

This population-based, descriptive, surveillance study examined physician-diagnosed COPD prevalence, incidence, and mortality in Turkey. The database of the Social Security System of Turkey was scanned and ICD-10 J44.0-J44.9 codes for diagnostic and/ or therapeutic purposes were evaluated retrospectively.

Results

In 2016, there were 3,434,262 cases of COPD (56.2% men) in Turkey, and the mean age of patients was 61.62 ± 14.76 years. From 2012 to 2016, the annual overall prevalence rates of physician-diagnosed COPD rose from 4.3% to 5.8%, which was a 35.0% relative increase (P < 0.05). In women, this rate rose from 3.7% to 5.1% (38% increase), and in men, it rose from 4.9% to 6.7% (37% increase). During the study period, the overall incidence decreased from 8.5 per 1000 adults in 2012 to 6.3 per 1000 adults in 2016, representing a decrease of 26.6% (P < 0.001). The annual incidence rates of physician-diagnosed COPD decreased 25.4% in women and 27.9% in men. The overall mortality was 4.3% in 2012, and 4.2% in 2016. The mortality rate in women was 3.5% in 2012 and 3.7% in 2016, and 5% in 2012 and 4.7% in 2016 in men. The mean prevalence by region was 5.26% (range 3.79%–7.65%). The Black Sea region had the highest COPD prevalence.

Conclusion

COPD is a very common and serious cause of morbidity and mortality in Turkey, as it is worldwide. Current data will contribute to a better understanding of the epidemiologic dimension of COPD in our country.

Risk of COPD due to indoor air pollution from biomass cooking fuel: a systematic review and meta-analysis

Chronic obstructive pulmonary disease (COPD) is one of the leading causes of mortality in developing nations. In this meta-analysis, we aimed to determine the association between indoor air pollution and risk of COPD. Database searches were conducted using indoor air pollution, biomass and COPD related terms to identify relevant articles. The eligible studies were case-control, retrospective cohort, cross-sectional studies and conducted in adults that assessed COPD using any diagnostic criteria. A total of 35 studies with 73,122 participants were included. The pooled analysis showed that exposure to indoor air pollution due to solid biomass fuels increased risk of COPD by 2.65 (95% confidence interval [CI] 2.13-3.31; n = 73,122) and chronic bronchitis by 2.89 (95% CI 2.18-3.82) times more compared to non-biomass fuels. The risk of COPD was higher in Africa region (odds ratio [OR] 3.19), Asia (OR 2.88), South America (OR 2.15), Europe (OR 2.30) and North America (OR 2.14). The results of our meta-analysis indicated that exposure to indoor air pollution due to biomass smoke is strongly associated with COPD.Abbreviations: CS: cross-sectional; CC: case-control; NR: not reported; ATS: American Thoracic Society; BMRC: British Medical Research Council; GOLD: Global Initiative for Obstructive Lung Disease; IAP: indoor air pollution; BMF: biomass fuel; CB: chronic bronchitis; OR: odds ratio; UCI; upper confidence interval; LCI: lower confidence interval; COPD: chronic obstructive pulmonary disease.

Short-term associations between size-fractionated particulate air pollution and COPD mortality in Shanghai, China

Particulate air pollution is a continuing challenge in China, and its adverse effects on chronic obstructive pulmonary disease (COPD) have been widely reported. However, epidemiological evidence on the associations between size-fractionated particle number concentrations (PNCs) and COPD mortality is limited. In this study, we utilized a time-series approach to investigate the associations between PNCs of particles at 0.25-10 μm in diameter and COPD mortality in Shanghai, China. Quasi-Poisson regression generalized additive models were applied to evaluate these associations, with adjustment of time trend, day of week, holidays, temperature and relative humidity. Stratification analyses were performed by season and gender. There were a total of 3238 deaths due to COPD during the study period. We found that daily COPD deaths were significantly associated with PNCs of particles <0.5 μm, and the magnitude of associations increased with decreasing particle size. An interquartile range (IQR) increase in PNC_0.25-0.28, PNC_0.28-0.3, PNC_0.3-0.35, PNC_0.35-0.4, PNC_0.4-0.45 and PNC_0.45--0.5 was associated with increments of 7.51% (95%CI: 2.45%, 12.81%), 7.22% (95%CI: 2.16%, 12.53%), 6.95% (95%CI: 1.81%, 12.35%), 6.26% (95%CI: 1.25%, 11.52%), 5.24% (95%CI: 0.56%, 10.13%) and 4.15% (95%CI: 0.14%, 8.32%), respectively. The associations remained robustness after controlling for the mass concentrations of gaseous air pollutants. In stratification analyses, significant associations between PNCs and COPD mortality were observed in the cold seasons, and in males. Our results suggested that particles <0.5 μm in diameter might be most responsible for the adverse effects of particulate air pollution on COPD mortality, and COPD patients are more susceptible to PM air pollution in the cold seasons, especially for males.

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.

Predictive Value of Combining Inflammatory Biomarkers and Rapid Decline of FEV1 for COPD in Chinese Population: A Prospective Cohort Study

Background

In China, the high prevalence and mortality rate of Chronic Obstructive Pulmonary Disease (COPD) and the poor intervention effect makes it into a heavy social burden. The main reason is that the current diagnosis of COPD mainly based on the static lung function, which is difficult for early intervention. Through matching a predictive model for high-risk groups of COPD that rewards FEV₁ rapid decline as the core, we will establish the early warning model and prove its validity and socio-economic value.

Methods

This is a multi-center, prospective, cohort study. A total of 10,000 people aged 40∼75 without lung disease will be recruited and followed for 3 years. Some questionnaires such as St George’s Respiratory Questionnaire (SGRQ), income class, educational level, comorbidity, smoking habit, and biomass smoke exposure history will be collected. The baseline level of Interleukin 6 (IL-6), high-sensitivity C-reactive Protein (hs-CRP), microRNAs-23a (miR-23a) in peripheral blood and pH value in exhaled breath condensate (EBC) will be measured, lung spirometry will be tested in the first, second, and fourth years. Primary outcome is the incidence of COPD, multivariate regression analysis will be used to establish the predictive model for COPD in China.

Discussion

With the rapid decline of lung function as the core and the baseline inflammatory biomarkers in peripheral blood and pH of the exhaled breath condensate as affecting factors, a predictive model to achieve early detection of high-risk COPD groups will be established and promoted.

Trial registration

This study has been registered at www.ClinicalTrials.gov (registration identifier: NCT03532893) on 21 May 2018, https://register.clinicaltrials.gov.

Association between F+1 polymorphism in a disintegrin and metalloprotease 33 (ADAM33) gene and chronic obstructive pulmonary disease susceptibility: An evidence-based meta-analysis

BACKGROUND

The F+1 (rs511898 G>A) polymorphism in a disintegrin and metalloprotease 33 (ADAM33) gene has been implicated in susceptibility of chronic obstruction pulmonary disease (COPD). However, a series of studies have reported inconclusive. The aim of this study is to explore the association between the F+1 (rs511898) of ADAM33 gene and COPD susceptibility by using the method of meta-analysis.

METHOD

PubMed, Embase, Cochrane Library, Chinese National Knowledge Infrastructure database (CNKI), Chongqing VIP database, Wanfang and China Biology Medicine (CBM) were searched comprehensively to obtain the related cohort studies and case-control studies. The included studies were selected according to inclusion criteria. The pooled odds ratios were performed respectively for allele comparison, additive model, dominant genetic model and recessive genetic model. The association between the F+1 polymorphism of ADAM33 gene and COPD susceptibility was measured by OR and 95%CI by STATA 12.0. The subgroup analysis was distinguished according to the ethnicity. The publication bias was tested by funnel plots and Egger's linear regression method.

RESULTS

Twelve case-control studies were included in the meta-analysis, which study is comprised of 6935 participants (2454 patients with COPD and 4481 controls). The meta results showed significant association between ADAM33 F+1 polymorphism and COPD susceptibility in allele model OR _total = 1.16(95% CI 1.04-1.30, P = 0.007), OR _Asian = 1.14(95% CI 1.02-1.27, P = 0.022), additive model OR _total = 1.27 (95% CI 1.13-1.43, P = 0.000), OR _Asian = 1.25 (95% CI 1.08-1.45, P = 0.003), recessive model OR _total = 1.49 (95% CI 1.16-1.91, P = 0.002), OR _Asian = 1.56(95% CI 1.09-2.22, P = 0.014), but not significant in Caucasians.

CONCLUSION

The ADAM33 F+1 mutant gene A may increase the risk of COPD among the Asian population, while it may not associate with the European population.

Prevalence, Awareness, and Associated Factors of Airflow Obstruction in Russia: The Ural Eye and Medical Study

Background: Although chronic obstructive pulmonary disease and asthma belong to the most important causes of disability and death in all world regions, data about the prevalence of airflow obstruction and asthma in Russia and the associated parameters have been scarce so far. We therefore assessed the prevalence of airflow obstruction and asthma in a Russian population. Methods: The population-based Ural Eye and Medical Study, conducted in a rural and urban region of Bashkortostan/Russia, included 5,392 participants (mean age: 58.6 ± 10.6 years; range: 40-94 years) out of 7,328 eligible individuals. Airflow obstruction was defined spirometrically and asthma by self-reported diagnosis. Results: Airflow obstruction was present in 369 individuals (6.8%; 95% confidence interval (CI): 6.2, 7.5) with an awareness rate of 63.4% (95%CI: 58.5, 68.4) and known duration of 19.5 ± 15.8 years (median: 16 years). Prevalence of undiagnosed airflow obstruction was 2.6% (95%CI: 2.2, 3.1). Higher prevalence of airflow obstruction was associated (multivariable analysis) with higher prevalence of current smoking [P < 0.001; odds ratio (OR): 2.91; 95%CI: 1.76, 4.83] and number of cigarette package years (P < 0.001; OR: 1.03; 95%CI: 1.02, 1.08), female gender (P = 0.03; OR: 1.42; 95%CI: 1.04, 1.93), urban region (P = 0.003; OR: 1.43; 95% CI: 1.12, 1.79), higher prevalence of cardiovascular diseases/stroke (P < 0.001; OR: 1.86; 95%CI: 1.45, 2.39), higher depression score (P = 0.002; OR: 1.05; 95%CI: 1.02, 1.08), and lower physical activity (P = 0.01; OR: 0.71; 95%CI: 0.54, 0.93). Asthma prevalence (2.6%; 95%CI: 2.0, 3.1; known duration: 17.2 ± 15.0 years) was associated with less alcohol consumption (OR: 0.53; 95%CI: 0.33, 0.87; P = 0.01), higher depression score (OR: 1.08; 95%CI: 1.03, 1.12; P < 0.001), and urban region (OR: 0.68; 95CI: 0.49, 0.95; P = 0.0.03). Conclusions: In this Russian population aged 40+ years, the prevalence of airflow obstruction was 6.8% with an awareness rate of 63.4% and smoking as main risk factor. Asthma prevalence was 2.6%.

Factors associated with appendicular skeletal muscle mass among male Chinese patients with stable chronic obstructive pulmonary disease: A hospital-based cross-sectional study

Limbs muscle wasting is a common disorder in patients with chronic obstructive pulmonary disease (COPD) that limits daily activities and exercise intolerance, especially in males. The present study aimed to estimate the prevalence of appendicular skeletal muscle mass (ASM) in male patients with stable COPD. In addition, factors associated with parameters of ASM were also investigated.We recruited 116 male patients with stable COPD from the outpatient clinic between September 2016 and December 2017. For each patient, we obtained demographic characteristics and measured post-bronchodilator forced expiratory volume in 1 second, symptoms, exacerbations history, and ASM. ASM was defined as the sum of the muscle masses of the 4 limbs.Appendicular skeletal muscle mass index (ASMI) in male patients with stable COPD was 8.2 ± 0.9 kg/m, and the prevalence of low skeletal muscle mass was 7.8% (9 of 116 patients). Multiple linear-regression analysis showed that body mass index, occupation, fat-free mass index, and the modified medical research council scale were significantly correlated with ASMI. Compared with nonexercise group, lower limb muscle mass and ASM were significantly improved in physical exercise group.Underweight, retirement, fat-free mass depletion, and severe dyspnea are all risk factors for ASM in male patients with stable COPD. Our findings also justify the importance of exercise training in improving ASM.

Dissection of Pharmacological Mechanism of Chinese Herbal Medicine Yihuo Huatan Formula on Chronic Obstructive Pulmonary Disease: A Systems Pharmacology-Based Study

Chronic obstructive pulmonary disease (COPD) is one of the most common respiratory diseases. Yihuo Huatan Formula (YHF), as a proven Chinese Herbal Medicine (CHM), has been verified to be effective in the treatment of stable COPD through years' of practice. Nevertheless, its working mechanism is still unclear. We sought to systematically decipher the mechanism of YHF for treating stable COPD using systems pharmacology-based method that integrates pharmacokinetic screening, target prediction, network analyses, GO and KEGG enrichment analyses. Firstly, a total of 1267 chemicals out of 15 herbal components were included in YHF chemical database. Among them, 180 potential active molecules were screened out through pharmacokinetic evaluation. Then 258 targets of the active molecules were predicted, of which 84 were chosen for further analyses. Finally, the network analyses and GO and KEGG enrichment methods suggested a therapeutic effect of YHF on the alleviation of airway inflammation, decrease of mucus secretion, maintenance of immune homeostasis and benefit of COPD comorbidities, by regulating multiple targets and pathways. The systems pharmacology-based approach helps to understand the underlying working mechanism of YHF in stable COPD from a holistic perspective, and offers an exemplification for systematically uncovering the action mechanisms of CHM.

Lyn regulates epithelial-mesenchymal transition in CS-exposed model through Smad2/3 signaling

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation that is progressive and not fully reversible. Cigarette smoking is one of the most commonly and important risk factors for COPD, which contributes to airway remodeling, the outstanding pathological changes in COPD. One potential mechanism which might be important for airway remodeling is the process called epithelial-mesenchymal transition (EMT). However, the underlying molecular mechanisms of EMT in CS-induced COPD are still poorly understood.

METHODS

Two Gene Expression Omnibus (GEO) datasets (GSE108134 and GSE5058) were combined to identify the key genes involved in COPD. Then, single-gene analysis of Lyn was performed. Lyn expression was confirmed in patients with COPD. 16HBE cells were treated with cigarette smoking extracts (CSE). Wild type (WT) C57BL/6 J mice and Lyn+/+ transgenic mice were exposed to CSE to establish CS-exposed model. Pathological changes were observed by hematoxylin-eosin staining. The expression levels of EMT markers were examined by using western blot and immunofluorescence. The expression and phosphorylation levels of Lyn and Smad2/3 were detected as well.

RESULTS

The gain of mesenchymal markers vimentin and α-SMA with a concomitant loss of E-cadherin was observed in both in vivo and in vitro studies. Meanwhile, cigarette smoking extracts (CSE) induced EMT in 16HBE cells in a time- and dose- dependent manner. Furthermore, by analyzing GEO datasets and using molecular methods, we explored a kinase, Lyn, its expression correlated with the expression of E-cadherin, vimentin and α-SMA in CS-exposed model. Moreover, we found that EMT induced by CSE was regulated by activated Lyn through phosphorylation of Smad2/3.

CONCLUSIONS

In summary, we found that Lyn regulates epithelial-mesenchymal transition in CS-exposed model through Smad2/3 signaling. As a kinase, Lyn is "druggable", and might provide a therapeutic opportunity for targeting EMT. Therefore, our research might provide a new method to treat COPD by targeting Lyn kinase specifically.

Investigation of the Prevalence and Diagnosis of Chronic Obstructive Pulmonary Disease in a Group of Elderly Individuals Residing in an Island Area of Ningbo

Objective

This epidemiological investigation aimed at determining the current situation regarding the diagnosis and treatment of chronic obstructive pulmonary disease (COPD), especially missed diagnosis and missed treatment, in a group of individuals residing in an island area of Ningbo.

Methods

Adults ≥60 years of age were selected from an island area of Ningbo. All participants completed a COPD-Screening Questionnaire and underwent a post-bronchodilator pulmonary function test. COPD-positive individuals then completed a questionnaire surveying the status of diagnosis and treatment of COPD and the reasons for missed diagnosis and treatment. The data were collated and analyzed using SPSS version 22.0 (IBM Corporation, Armonk, NY, USA).

Findings

(1) A total of 1526 individuals were screened, of whom 1371 (89.8%) were eventually included in data analysis. From these, 254 were diagnosed with spirometry-defined COPD, corresponding to an overall prevalence of 18.5%. Prevalence was higher in men (28.9%) than in women (8.3%) among the sample. (2) According to chi-squared test results, risk factors for COPD included sex, age, smoking history (pack-years), cough, and dyspnea. Body mass index, family history of respiratory diseases, and exposure to biomass smoke from cooking were not risk factors for COPD. (3) Multivariate logistic regression analysis revealed that age and smoking were independent risk factors for COPD. (4) Receiver operating curve analysis revealed that, at a cutoff of 19.5, the highest sum of sensitivity and specificity was 69.7% and 75.5%, respectively. The COPD-Screening Questionnaire could be used as a preselection method to screen for COPD in primary care settings. (5) Of 254 individuals diagnosed with COPD, only 10 had a history of COPD and only 35 had a previous diagnosis of pneumonia or bronchitis. These data revealed that the rate of missed diagnosis of COPD in the Ningbo island area was 96.1%.

Conclusion

The prevalence of COPD among elderly individuals in the Ningbo island area was significantly higher than in other parts of China. Moreover, the rate of missed diagnosis of COPD in the Ningbo island area was extremely high. Smoking and age were independent factors for the occurrence of COPD.

Association between chronic obstructive pulmonary disease and activity of daily living among oldest-old in China: based on Chinese Longitudinal Health Longevity Survey

Aims

This study was designed to investigate the association between COPD and activity of daily living among oldest-old in People's Republic of China.

Patients and methods

The data of Chinese Longitudinal and Health Longevity Study in 2014 was used, and those who were aged more than 80 years old were included. Both basic activity of daily living (BADL) and instrumental activity of daily living (IADL) were measured.

Results

A total of 4621 oldest-old (≥80 years old) were included. 32.1% (1482) of the oldest-old had BADL disability and 79.0% (3129) had IADL disability. The BADL disability and IADL disability rates were higher for participants with COPD than those without, and this difference was more robust among male (31.8% vs 25.6%, p=0.018). The IADL disability rate showed similar trends. Multivariate logistic regression analysis showed that the odds ratios of COPD on BADL disability and IADL disability were 1.261 (95% CI: 1.044–1.525) and 2.014 (95% CI: 1.561–2.598), respectively. The odds ratios of COPD on moderate to severe BADL disability and IADL disability were 1.007 (95% CI: 0.790–1.284) and 1.713 (95% CI: 1.397–2.100), respectively.

Conclusion

There were independent associations between COPD and disability among oldest-old in People's Republic of China, and the associations were greater among male population. Besides, COPD had a profound influence on the mild disability of BADL, while had a greater impact on the moderate and severe disability of IADL.

PM10-related DNA damage, cytokinetic defects, and cell death in COPD patients from Chiang Dao district, Chiang Mai, Thailand

Exposure to PM₁₀ generated by biomass burning may reduce lung function and induce cytogenetic effects, especially in chronic obstructive pulmonary disease patients. This study investigated the frequency of DNA-damaged cells, cells with cytokinetic defect, and different types of cell death using a buccal micronucleus cytome assay. The correlations between each biomarker and lung function were investigated. The changes in these biomarkers associated with high pollutant levels (PM₁₀ > 50 μg/m³) and low pollutant levels (PM₁₀ < 50 μg/m³) were evaluated to explore whether PM₁₀ exposure induced genotoxic damages and cytokinetic defects in COPD patients when the daily average PM₁₀ concentration reached above 50 μg/m³. Fifty-eight COPD patients and 26 healthy subjects living in Chiang Dao district, Chiang Mai, Thailand, were recruited in this study. The results revealed that buccal cells with micronuclei (high vs low 1.09 ± 1.95 vs 0.29 ± 0.64 in COPD patients) and binucleated cells (high vs low 11.43 ± 18.68 vs 1.60 ± 1.31 and 7.77 ± 12.76 vs 1.00 ± 1.17 in COPD and healthy subjects, respectively) observed during the high pollutant period were more frequent than in the low pollutant period. Moreover, exposure to PM₁₀ increased the risk of micronucleus induction in COPD patients 295.23-fold.

Ursolic acid alleviates airway-vessel remodeling and muscle consumption in cigarette smoke-induced emphysema rats

BACKGROUND

This study assessed the effects of ursolic acid (UA) on airway-vessel remodeling and muscle atrophy in cigarette smoke (CS)-induced emphysema rats and investigated potential underlying mechanisms.

METHODS

Emphysema was induced in a rat model with 3 months of CS exposure. Histology and immunohistochemistry (IHC) stains were used to assess airway-vessel remodeling and muscle atrophy-associated changes. Levels of cleaved-caspase3, 8-OHdG, and S100A4 were measured in airways and associated vessels to evaluate cell apoptosis, oxidant stress, epithelial-to-mesenchymal transition (EMT), and endothelial-to-mesenchymal transition (EndMT)-associated factors. Western blot and/or IHC analyses were performed to measure transforming growth factor-beta 1(TGF-β1)/Smad2.3, alpha-smooth muscle actin (α-SMA), and insulin-like growth factor 1 (IGF1) expression. We also gave cultured HBE and HUVEC cells Cigarette Smoke Extract (CSE) administration and UA intervention. Using Western blot method to measure TGF-β1/Smad2.3, α-SMA, S100A4, and IGF1 molecules expression.

RESULTS

UA decreased oxidant stress and cell apoptosis in airway and accompanying vascular walls of cigarette smoke-induced emphysema model rats. UA alleviated EMT, EndMT, changes associated with airway-vessel remodeling and muscle atrophy. The UA effects were associated with IGF1 and TGF-β1/Smad2.3 pathways.

CONCLUSIONS

UA reduced EMT, EndMT, airway-vessel remodeling, and musculi soleus atrophy in CS-induced emphysema model rats at least partly through IGF1 and TGF-β1/Smad2.3 signaling pathways.

Effect of thallium exposure and its interaction with smoking on lung function decline: A prospective cohort study

BACKGROUND

Thallium (Tl) is a cumulative high toxicant in the environment, but few longitudinal studies have investigated the respiratory impairment of Tl exposure.

OBJECTIVES

This study aimed to evaluate the effect of Tl and its interaction with smoking on lung function decline, and explore the potential mechanisms.

METHODS

The baseline and follow-up lung functions were measured from a prospective cohort study of 1243 workers, who were followed from 2010 to 2014. Their baseline urinary levels of Tl were determined. We also measured the plasma C-reactive protein (CRP) and urinary 8-iso-prostaglandin-F2α (8-iso-PGF2α) in a randomly selected subcohort of 474 subjects.

RESULTS

The results showed that a 2-fold increase in urinary Tl was associated with 29.81 mL (95%CI: 3.83-55.80) increased decline in forced expiratory volume in 1 s (FEV₁). The effect was more pronounced among heavy-smokers (≥15 pack-years) [β(95%CI) = 56.42 mL (9.66-103.19)]. In particular, compared to never-smokers with low Tl, heavy-smokers with high Tl had a separate 158.44 mL (95%CI: 54.88-262.00) and 4.58% (95%CI: 1.40-7.76) increased declines in FEV₁ and percentage of predicted (ppFEV₁), respectively. There was a significant interaction between Tl and smoking intensity on ppFEV₁ decline (P_int = 0.034). More importantly, the increasing level of urinary Tl was correlated with elevated CRP and 8-iso-PGF2α.

CONCLUSION

Our prospective cohort study identified that exposure to high Tl had a deleterious effect on lung function, and this effect may be enhanced by tobacco smoking. Increased inflammation may partly contribute to the joint effects of Tl and smoking on impaired lung function, but the biological mechanisms need further explorations.

Bacterial etiology in early re-admission patients with acute exacerbation of chronic obstructive pulmonary disease

Background

Repeatedly hospitalized patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) are often exposed to more antibiotics, but the distribution of pathogenic bacteria in these patients is poorly understood. The objectives of this study were to analyze the distribution of pathogenic bacteria and the risk factors associated with multidrug-resistant (MDR) bacteria infection in early re-admission patients with AECOPD.

Methods

We retrospectively reviewed charts for patients with AECOPD admitted to our hospital between January 2011 and November 2012. The early re-admission group and non-early readmission group were determined by whether patients were readmitted within 31 days after discharge. Detection of potentially pathogenic microorganisms (PPMs) and MDR bacteria were analyzed. Logistic regression analysis was performed to identify independent risk factors for MDR bacteria infection.

Results

PPMs were isolated from 230 (32.0%) cases of respiratory tract specimens; MDR bacteria accounted for 24.7% (57/230). Pseudomonas aeruginosa (43.7%), Klebsiella pneumoniae (15.6%), and Acinetobacter baumannii (12.5%) were the top three PPMs in the early readmission group, while the top three PPMs in the non-early readmission group were K. pneumoniae (23.7%), P. aeruginosa (21.2%), and Streptococcus pneumoniae (17.1%). Multivariate analysis showed that use of antibiotics within 2 weeks (odds ratio [OR] 8.259, 95% confidence interval [CI] 3.056–22.322, p = 0.000) was the independent risk factor for MDR bacteria infection.

Conclusion

Non-fermentative Gram-negative bacilli (NFGNB) and enterobacteria were the predominant bacteria in early readmission patients with AECOPD. The detection rate of MDR bacteria was high which was related to the use of antibiotics within 2 weeks before admission in these patients.

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 and risk factors of chronic obstructive pulmonary disease in Anhui Province, China: a population-based survey

BACKGROUND

The prevalence of chronic obstructive pulmonary disease (COPD) in Anhui Province of eastern China remain uncertain. The present study provides the first estimate of the prevalence and risk factors of COPD in Anhui.

METHODS

A population-based survey was conducted in a representative sample of population aged 40 years or older in 2015. COPD was diagnosed based on 2017 Global Initiative for Chronic Obstructive Lung Disease (GOLD) criteria.

RESULTS

A total of 2770 participants had reliable post-bronchodilator results and were included in the final analysis. The overall prevalence of COPD was 9.8% (95% CI: 8.2, 11.7). Prevalence was higher in men (14.8, 95% CI: 12.6, 17.2) than it was in women (5.2, 95% CI: 3.1, 8.7). Among adults with COPD, 45.0% (95% CI: 39.1, 51.0) had moderate or severe disease (GOLD stage II-IV), 0.7% (95% CI: 0.2, 2.9) reported that they had a previous pulmonary function test, and only 0.4% (95% CI: 0.1, 2.6) knew their diagnosis of COPD. Risk factors for COPD included older age (OR 1.06, 95% CI: 1.04, 1.08), male sex (OR 2.01, 95% CI: 1.22, 3.33), current smoking status (OR 2.63, 95% CI: 1.86, 3.73), primary school or lower education (OR 1.61, 95% CI: 1.12, 2.31), family history of lung disease (OR 1.50, 95% CI: 1.17, 1.93), and indoor exposure to coal for cooking or heating (OR 1.55, 95% CI: 1.11, 2.15). In addition, people in north region has a significantly higher risk for developing COPD than people in south region of Anhui (OR 1.98, 95% CI:1.44, 2.71).

CONCLUSIONS

COPD is prevalent in Anhui and the prevalence is highest in north region. Strategies aiming at prevention, early detection and treatment of COPD are urgently needed to reduce COPD-related burden.

The efficacy of mindfulness-based interventions for patients with COPD: a systematic review and meta-analysis protocol

INTRODUCTION

Chronic obstructive pulmonary disease (COPD) is a common chronic respiratory disease. It has adverse effects on patients' physical health, mental well-being and quality of life. The purpose of mindfulness-based interventions (MBIs) is to raise non-judgemental awareness and attention to current internal and external experiences. This means the attention is shifted from perceived and involuntary inner activities to current experience, keeping more curious, open and accepting attitudes towards current experience. Although some studies on the intervention effect of MBIs in patients with COPD have been conducted, the results are controversial, especially on dyspnoea, level of mindfulness and quality of life. Therefore, a systematic review of MBIs in patients with COPD is required to provide available evidence for further study.

METHODS AND ANALYSIS

In this study, different studies from various databases will be involved. Randomised controlled trials(RCTs)/quantitative studies, qualitative studies and case studies on the effect of MBIs in patients with COPD aged over 18 years will be included. We will search the literature in the databases of PubMed, Excepta Medica Base (EMBASE), Web of Science, Cumulative Index to Nursing and Allied Health Literature (CINAHL), the Cochrane Library, PsycINFO and China National Knowledge Infrastructure(CNKI). The primary outcomes will include efficacy of MBIs for patients with COPD in terms of dyspnoea, depression and anxiety. The secondary outcomes will include efficacy of MBIs in terms of quality of life, mindful awareness, 6-minute walk test(6MWT) and nutritional risk index. Data extraction will be conducted by two researchers independently, and risk of bias of the meta-analysis will be evaluated based on the Cochrane Handbook for Systematic Reviews of Interventions. All data analysis will be conducted by data statistics software Review Manager V.5.3. and Stata V.12.0.

ETHICS AND DISSEMINATION

Since this study is a systematic review, the findings are based on the published evidence. Therefore, examination and agreement by the ethics committee are not required in this study. We intend to publish the study results in a journal or conference presentations.

PROSPERO REGISTRATION NUMBER

CRD42018102323.

New insights into early intervention of chronic obstructive pulmonary disease with mild airflow limitation

Chronic obstructive pulmonary disease (COPD) has become one of the major public health problems worldwide due to its high morbidity and mortality. Up until now, COPD is still under-diagnosed and under-treated, especially for mild or moderate patients. It is widely accepted that the majority of patients with COPD are in the early stages, yet this subpopulation is underestimated. In recent years, growing evidence indicates that substantial physiological and clinical abnormalities exist in patients with mild COPD compared with healthy controls. Furthermore, recent studies suggest that pharmacologic intervention in early COPD has the potential to alter clinical outcomes. The main objective of this review is to summarize recent research regarding the heterogeneous pathophysiology, clinical features, and treatment of mild and moderate COPD. We also discuss promising markers of disease progression, which may contribute to the development of precision medicine in early COPD.