Chronic obstructive pulmonary disease (COPD) continues to be a significant issue, leading to premature death or reduced quality of life. It’s important to assess the current burden of COPD and its risk factors on a geographical basis to guide health policy. Data on the prevalence, deaths, and disability-adjusted life years (DALYs) related to COPD, and risk-attributable burden were obtained from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 database. The relationship between COPD DALYs and the sociodemographic index (SDI) was estimated using Smoothing Splines models. Between 1990 and 2021, the changes were -1.46% (95% uncertainty interval [UI] -3.36% to 0.39%) in age-standardized prevalence, -37.12% (-43.37% to -27.68%) in mortality, and -36.98% (-42.37% to -28.54%) in DALYs rate. In 2021, a total of 213.39 million prevalent cases of COPD were estimated. The age-standardized prevalence of COPD increased with age and was more common in males. The age-standardized COPD DALYs had a reversed U-shaped relationship with SDI at the regional level, with the highest burden at an SDI of about 0.45. At the global level, smoking had the highest influence on COPD DALYs, accounting for 34.8%, followed by ambient particulate matter pollution (22.2%), household air pollution from solid fuels (19.5%), and occupational particulate matter, gases, and fumes (15.8%). The overall burden of COPD has been increasing despite improvements in some rates since 1990. It’s crucial to focus on interventions such as smoking cessation and addressing environmental and occupational exposures.

Besides the impaired lung diffusion capacity, impairment of exercise endurance in recovered patients with COVID-19 should also be concerned

Background: Respiratory oscillometry is a promising complement to the traditional pulmonary function tests for its simplicity. The usefulness of oscillometry in adult clinical practice has not been clarified. This study aimed to analyse the characteristics and diagnostic performance of oscillometry in respiratory diseases, and explore the cut-offs of oscillometric parameters for severity grading.Methods: In this multicentre registry of impulse oscillometry (IOS), IOS and spirometric data of healthy individuals and patients with respiratory diseases were collected and analysed. Linear mixed model analysis was performed to explore the effects of disease and forced expiratory volume in 1 s (FEV₁) on oscillometric parameters.Results: The study included 567 healthy subjects, 781 asthmatic patients, 688 patients with chronic obstructive pulmonary disease (COPD), 109 patients with bronchiectasis, 40 patients with upper airway obstruction (UAO) and 274 patients with interstitial lung disease (ILD) in the analysis. Compared at the same FEV₁level, asthma, COPD, bronchiectasis, UAO and ILD displayed different oscillometric characteristics. The z-score of resistance at 5 Hz (R₅) was the best variable to identify respiratory diseases with a sensitivity of 62.4–66.7% and a specificity of 81.5–90.3%. With reference to the severity grading cut-offs of FEV₁,R₅z-scores of 2.5 and 4 were defined as the cut-off values of moderately and severely increasedR₅.Conclusion: Respiratory oscillometry is more appropriate to be a tool of evaluating, rather than of diagnosing, respiratory diseases. A severity grading system of oscillometric parameters was developed to help the interpretation of oscillometry in clinical practice.

Background: Impulse oscillometry (IO) is a non-invasive pulmonary function test for measuring respiratory impedance. Available reference equations of IO indices for adults are limited. The aim of this study was to develop reference equations of IO indices for Chinese adults. Methods: In a multicentral, cross-sessional study of IO in Chinese adults, IO data from healthy subjects were collected from 19 general hospitals across China between 2016 and 2018. Oscillometry measurements were conducted in accordance with recommendations of the European Respiratory Society (ERS). Multiple linear regression was performed to develop sex-specific reference equations of IO indices. Results: IO measurements were performed in 1,318 subjects, of which 567 subjects were defined as healthy individuals with acceptable IO data and were included in the final analysis. Reference equations and limits of normal [lower limit of normal (LLN)/upper limit of normal (ULN)] of IO indices were developed separately for males and females. Height but not age was shown to be the most influential contributor to IO indices. The reference equations currently used in lung function laboratories predicted higher R5 and X5. Normal ranges of R5 and X5 recommended by the equipment manufacturer were clearly different from the ULN/LLN derived from the reference equations. Conclusions: Reference equations of IO indices for Chinese adults from a wide region were provided in this study. It is necessary to update new IO reference equations and adopt ULN/LLN as normal ranges of IO indices. Trial Registration: This study was registered at www.clinicaltrials.gov as part of a larger study NCT03467880.

Background: Spirometry quality assurance is a challenging task across levels of healthcare tiers, especially in primary care. Deep learning may serve as a support tool for enhancing spirometry quality. We aimed to develop a high accuracy and sensitive deep learning-based model aiming at assisting high-quality spirometry assurance. Methods: Spirometry PDF files retrieved from one hospital between October 2017 and October 2020 were labeled according to ATS/ERS 2019 criteria and divided into training and internal test sets. Additional files from three hospitals were used for external testing. A deep learning-based model was constructed and assessed to determine acceptability, usability, and quality rating for FEV₁ and FVC. System warning messages and patient instructions were also generated for general practitioners (GPs). Results: A total of 16,502 files were labeled. Of these, 4592 curves were assigned to the internal test set, the remaining constituted the training set. In the internal test set, the model generated 95.1%, 92.4%, and 94.3% accuracy for FEV₁ acceptability, usability, and rating. The accuracy for FVC acceptability, usability, and rating were 93.6%, 94.3%, and 92.2%. With the assistance of the model, the performance of GPs in terms of monthly percentages of good quality (A, B, or C grades) tests for FEV₁ and FVC was higher by ~ 21% and ~ 36%, respectively. Conclusion: The proposed model assisted GPs in spirometry quality assurance, resulting in enhancing the performance of GPs in quality control of spirometry.

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.