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Studies have shown that short- and long-term exposure to particulate matter (PM) can increase the risk of asthma morbidity and mortality. However, the effect of medium-term exposure remains unknown. We aim to examine the effect of medium-term exposure to size-fractioned PM on asthma exacerbations among asthmatics with poor medication adherence. We conducted a longitudinal study in China based on the National Mobile Asthma Management System Project that specifically and routinely followed asthma exacerbations in asthmatics with poor medication adherence from April 2017 to May 2019. High-resolution satellite remote-sensing data were used to estimate each participant's medium-term exposure (on average 90 days) to size-fractioned PM (PM 1 , PM 2.5 , and PM 10) based on the residential address and the date of the follow-up when asthma exacerbations (e.g., hospitalizations and emergency room visits) occurred or the end of the follow-up. The Cox proportional hazards model was employed to examine the hazard ratio of asthma exacerbations associated with each PM after controlling for sex, age, BMI, education level, geographic region, and temperature. Modelling results revealed nonlinear exposure-response associations of asthma exacerbations with medium-term exposure to PM 1 , PM 2.5 , and PM 10. Specifically, for emergency room visits, we found an increased hazard ratio for PM 1 above 22.8 µg/m3 (1.060, 95 % CI: 1.025–1.096, per 1 µg/m3 increase), PM 2.5 above 38.2 µg/m3 (1.032, 95 % CI: 1.010–1.054), and PM 10 above 78.6 µg/m3 (1.019, 95 % CI: 1.006–1.032). For hospitalizations, we also found an increased hazard ratio for PM 1 above 20.3 µg/m3 (1.055, 95 % CI: 1.001–1.111) and PM 2.5 above 39.2 µg/m3 (1.038, 95 % CI: 1.003–1.074). Furthermore, the effects of PM were greater for a longer exposure window (90–180 days) and among participants with a high BMI. This study suggests that medium-term exposure to PM is associated with an increased risk of asthma exacerbations in asthmatics with poor medication adherence, with a higher risk from smaller PM. [Display omitted] • We examined the effects of PM on asthmatics with poor medication adherence. • We first reveal the effect of medium-term exposure to PM on asthma exacerbations. • Exposure to smaller particles has a greater effect on asthma exacerbations. [ABSTRACT FROM AUTHOR]

Introduction: The GAP model was widely used as a simple risk "screening" method for patients with idiopathic pulmonary fibrosis (IPF)., Objectives: We sought to validate the GAP model in Chinese patients with IPF to evaluate whether it can accurately predict the risk for mortality., Methods: A total of 212 patients with IPF diagnosed at China-Japan Friendship Hospital from 2015 to 2019 were enrolled. The latest follow-up ended in September 2022. Cumulative mortality of each GAP stage was calculated and compared based on Fine-Gray models for survival, and lung transplantation was treated as a competing risk. The performance of the model was evaluated in terms of both discrimination and calibration., Results: The cumulative mortality in patients with GAP stage III was significantly higher than that in those with GAP stage I or II (Gray's test p < 0.0001). The Harrell c-index for the GAP calculator was 0.736 (95% CI: 0.667-0.864). The discrimination for the GAP staging system were similar with that for the GAP calculator. The GAP model overestimated the mortality rate at 1- and 2-year in patients classified as GAP stage I (6.90% vs. 1.77% for 1-year, 14.20% vs. 6.78% for 2-year)., Conclusions: Our findings indicated that the GAP model overestimated the mortality rate in mild group., (© 2022 The Authors. The Clinical Respiratory Journal published by John Wiley & Sons Ltd.)

Background: Recent years, idiopathic pulmonary fibrosis (IPF) is thought to be a disease of alveoli as well as small airways. This study aimed to demonstrate the clinical feature, predictor, and prognosis of small airway dysfunction (SAD) in Chinese patients with IPF., Methods: We enrolled 416 patients with IPF who hospitalized in Beijing Chao-Yang Hospital from 2000 to 2014 in this study, and the follow-up ended at December 2016. We collected demographic information, clinical examination results, spirometry results, HRCT results, and blood gas results during the study. Logistic regression analysis was used to identify the predictor for SAD. The COX proportional hazard model was used to analysis the prognosis effect of SAD., Results: Among all the participants, 165 (39.66%) patients had SAD. FEV1 (% predicted) and FEV3/FVC were significantly associated with SAD in patients with IPF. IPF patients with lower FEV1 (% predicted, OR 30.04, 95% CI 9.61-93.90) and FEV3/FVC (OR 77.76, 95% CI 15.44-391.63) had increased risk for SAD. Patients with SAD were associated with significantly increased risk of mortality in patients with IPF (HR 1.73, 95% CI 1.02-2.92), as well as in IPF patients without other pulmonary comorbidities (COPD, emphysema, and asthma)., Conclusions: Spirometry-defined SAD was like 40% in patients with IPF. Lower FEV1 (% predicted) and FEV3/FVC were main predictors for SAD. IPF patients with SAD showed poorer prognosis., (© 2022. The Author(s).)

Introduction: Idiopathic pulmonary fibrosis (IPF) is a progressive and lethal lung disease characterised by a fibrotic histological pattern found in usual interstitial pneumonia. Its causes, pathogenesis, clinical phenotype and molecular mechanisms are poorly defined. Large-scale, multicentre studies are warranted to better understand IPF as a disease in China, its associated risk factors, clinical characteristics, diagnosis, disease progression and treatment., Methods and Analysis: The Idiopathic Pulmonary Fibrosis Registry China Study (PORTRAY) is a prospective, multicentre registry study of patients with IPF in China. Eight hundred patients will be enrolled over a 36-month period and followed for at least 3 years to generate a comprehensive database on baseline characteristics and various follow-up parameters including patient-reported outcomes. Biological specimens will also be collected from patients to develop a library of blood, bronchoalveolar lavage fluid and lung biopsy samples, to support future research. As of 15 December 2019, 204 patients from 19 large medical centres with relatively high IPF diagnosis and treatment rates had been enrolled. Patient characteristics will be presented using descriptive statistics. The Kaplan-Meier method will be used for survival analyses. Repeated measures will be used to compare longitudinal changes in lung function, imaging and laboratory tests. Results following analysis have been projected to be available by July 2025., Ethics and Dissemination: The study protocol was reviewed and approved by the Institutional Review Board from all the study sites currently recruiting patients. Study results will be published in peer-reviewed journals., Trial Registration Number: NCT03666234., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)