Background: The burden of asthma in terms of premature death or reduced quality of life remains a huge issue. It is of great importance to evaluate asthma burden geographically and time trends from 1990 to 2019 and to assess the contributions of age, period, and cohort effects at global level. Methods: Asthma prevalence, deaths, and disability adjusted life years (DALYs) as well as risk-attributable burden were collected from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 database and were compared by age and sex. The Smoothing Splines models were used to estimate the relationship between asthma DALYs and the sociodemographic index (SDI). The Age-Period-Cohort model was used to determine effects of ages, periods, and birth cohorts on disease rates. Results: Between 1990 and 2019, the declines were 24.05% (95% uncertainty interval [UI] − 27.24 to − 20.82) in age-standardized asthma prevalence, 51.3% (− 59.08 to − 43.71) in mortality, and 42.55% (− 48.48 to − 36.61) in DALYs rate. However, the burden of asthma continued to rise, with an estimated 262.41 million prevalent cases globally (95% UI 224.05 to 309.45). Asthma caused greater DALYs in females than in males among people aged 20 years and older. The lowest age-standardized DALYs rate was observed at a SDI of approximately 0.70. The Longitudinal age curves showed an approximate W-shaped pattern for asthma prevalence and a likely J-shaped pattern for asthma mortality. The period effect on prevalence and mortality of asthma decreased from 1990 to 2019. Compared with the 1955–1959 birth cohort, the prevalence relative risk (RR) of asthma was highest in the 1905–1909 birth cohort, whereas the mortality RR continued to decline. At the global level, the percentages of high body-mass index, occupational asthmagens, and smoking contributing to DALYs due to asthma were 16.94%, 8.82%, and 9.87%, respectively. Conclusions: Although the age-standardized rates of asthma burden declined in the past 30 years, the overall burden of asthma remains severe. High body mass index becomes the most important risk factor for DALYs due to asthma at the global level.

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.

Chronic obstructive pulmonary disease (COPD) is a clinical syndrome encompassing a group of chronic, progressive, and debilitating respiratory conditions, that are characterized by incompletely reversible airflow limitation. Within the Asia-Pacific region, prevalence estimates have been derived using various protocols and study methods, and there is little data on the impact of COPD exacerbations. This study aimed to provide a comprehensive picture of the current prevalence and burden of COPD in this region. A population-based survey was conducted in nine Asia-Pacific territories between 01 February 2012 and 16 May 2012. Overall, 112,330 households were screened to identify eligible subjects (aged ≥40 years, with a physician diagnosis of COPD, chronic bronchitis or emphysema, or with identifiable symptoms of chronic bronchitis). Out of a sample of 69,279 individuals aged ≥40 years, 4,289 subjects with COPD were identified. Data were collected via face-to-face interviews or by fixed-line telephone, using a structured questionnaire. A total of 1,841 completed questionnaires were analyzed. The overall estimated COPD prevalence was 6.2%, with 19.1% of subjects having severe COPD. In the 12 months prior to the survey, nearly half of all subjects (46%) had experienced exacerbations, and 19% had been hospitalized as a result of their condition. When subjects were asked about the impact of their condition on employment, 23% said their condition kept them from working, and 42% felt that their condition limited their ability to work or their activities. Of those who reported taking prescription drugs, 20% did not know the name of the drugs they were taking. Prescription of oral corticosteroids was common, with 44% of subjects having used these during the previous year to manage their respiratory symptoms; in contrast, inhaler use was low (25%). Only 37% of subjects had taken a lung function test, and the majority (89%) of those tested did not know their test results. Across the Asia-Pacific territories surveyed, the prevalence of COPD is high, indicating a substantial socioeconomic burden. Our findings suggest that there is considerable room for improvement in the management of COPD, and highlight a need to enhance patient and physician education in the region.

Background: Although there are over 1.34 billion Chinese in the world, nationwide spirometric reference values for Chinese are unavailable, which is usually based on Caucasian conversion. The aim of this study was to establish spirometric reference values for Chinese with a national wide sample. Methods: We enrolled healthy non-smokers in 24 centers in Northeast, North, Northwest, Southwest, South, East and Central China from January 2007 to June 2010. Spirometry was performed according to American Thoracic Society and European Respiratory Society guidelines. Reference equations were established using the Lambda-Mu-Sigma (LMS) method for forced expiratory volume in 1 second (FEV₁), forced vital capacity (FVC), FEV₁/FVC, peak expiratory flow (PEF) and maximal midexpiratory flow (MMEF). Popular Caucasian reference values adjusted with ethnic conversion factors were validated with Chinese measured spirometry data. The present study also compared with other published Chinese equations for spirometry. Results: A total of 7,115 eligible individuals aged 4 to 80 years (50.9% females) were recruited. Reference equations against age and height by gender were established, including predicted values and lower limits of normal (LLNs). Validated with Chinese data, the mean percentage differences of Caucasian reference values adjusted with ethnic conversion factors were −10.2% to 1.8%, and the percentages of total subjects under LLNs were 0.1% to 8.9%. Compared with this study, the percentage differences of previous Chinese studies ranged from −17.8% to 11.4%, which were found to significantly overestimate or underestimate lung function. Conclusions: This study established new reference values for better interpretation of spirometry in Chinese aged 4 to 80 years, while Caucasian references with adjustment were inappropriate for Chinese.

The Global Initiative for Chronic Obstructive Lung Disease (GOLD) report states that the diagnosis of COPD should be considered in individuals with chronic respiratory symptoms and/or exposure to risk factors. Forced spirometry demonstrating airflow obstruction after bronchodilation is required to confirm the diagnosis using a threshold of forced expiratory volume in 1 s (FEV₁)/forced vital capacity (FVC) ratio <0.7. This GOLD Science Committee review weighs the evidence for using pre- or post-bronchodilator (BD) spirometry to diagnose COPD. Cohort studies have shown that pre- and post-BD spirometry give concordant diagnostic results in most cases, although the prevalence of COPD is up to 36% lower with post-BD values. Discordant results may occur in “volume” or “flow” responders. Volume responders have reduced FVC due to gas trapping causing FEV₁/FVC ≥0.7 pre-BD, but a volume response occurs post-BD with a greater improvement in FVC relative to FEV₁decreasing the ratio to <0.7. Flow responders show a greater FEV₁improvement relative to FVC which may increase FEV₁/FVC from <0.7 pre-BD to ≥0.7 post-BD; these individuals have an increased likelihood of developing post-BD obstruction during follow-up and require monitoring longitudinally. GOLD 2025 recommends using pre-BD spirometry to rule out COPD and post-BD measurements to confirm the diagnosis. This will reduce clinical workload. Post-BD results close to the threshold should be repeated to ensure a correct diagnosis is made. Post-BD measurements ensure that volume responders are not overlooked and limit COPD overdiagnosis.

Background: Airway mucus hypersecretion is one of the important pathological features of chronic obstructive pulmonary disease (COPD). MUC5B is the main mucin expressed in the airways of COPD patients and has been indicated to play an important role in airway defense. However, the specific biological function of MUC5B in COPD and the possible mechanism are not clear. Methods: We established a COPD model with 24-week-old MUC5B^−/− mice exposed to cigarette smoke and tested our hypothesis through lung function tests, HE and PAS staining, immunohistochemistry (IHC), western blot, q-PCR and ELISA. Results: Compared with MUC5B^+/+ mice, MUC5B^−/− mice had worse general condition and lung function, increased inflammatory infiltration, reduced goblet cell differentiation as indicated by decreased PAS staining (PAS grade: 1.8 ± 0.24 vs. 0.6 ± 0.16), reduced MUC5AC expression (ELISA: 0.30 ± 0.01 vs. 0.17 ± 0.01 mg/ml, q-PCR: 9.4 ± 1.7 vs. 4.1 ± 0.1 fold, IHC score: 3.1 ± 0.9 vs. 1.6 ± 0.7), increased macrophage secretion of inflammatory factors (TNF-α and IL-6) and expression of downstream pathway factors (ERK1/2 and NF-κB), decreased expression of SPDEF and STAT6, and increased expression of FOXA2. Conclusion: The protective effect of MUC5B in the development of COPD was mediated by the promotion of goblet cell differentiation and the inhibition of inflammation. The role of MUC5B in regulating inflammation was related to macrophage function, and goblet cell differentiation was promoted by the induced expression of STAT6 and SPDEF. This study describes a mechanism of mucus hypersecretion and identifies MUC5B as a new target for the treatment of mucus hypersecretion.