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Summary: Background: Asthma is a chronic respiratory disease without a cure, although there exists spontaneous remission. Genome‐wide association (GWA) studies have pinpointed genes associated with asthma development, but did not investigate asthma remission. Objective: We performed a GWA study to develop insights in asthma remission. Methods: Clinical remission (ClinR) was defined by the absence of asthma treatment and wheezing in the last year and asthma attacks in the last 3 years and complete remission (ComR) similarly but additionally with normal lung function and absence of bronchial hyperresponsiveness (BHR). A GWA study on both ClinR and ComR was performed in 790 asthmatics with initial doctor diagnosis of asthma and BHR and long‐term follow‐up. We assessed replication of the 25 top single nucleotide polymorphisms (SNPs) in 2 independent cohorts (total n = 456), followed by expression quantitative loci (eQTL) analyses of the 4 replicated SNPs in lung tissue and epithelium. Results: Of the 790 asthmatics, 178 (23%) had ClinR and 55 ComR (7%) after median follow‐up of 15.5 (range 3.3‐47.8) years. In ClinR, 1 of the 25 SNPs, rs2740102, replicated in a meta‐analysis of the replication cohorts, which was an eQTL for POLI in lung tissue. In ComR, 3 SNPs replicated in a meta‐analysis of the replication cohorts. The top‐hit, rs6581895, almost reached genome‐wide significance (P‐value 4.68 × 10−7) and was an eQTL for FRS2 and CCT in lung tissue. Rs1420101 was a cis‐eQTL in lung tissue for IL1RL1 and IL18R1 and a trans‐eQTL for IL13. Conclusions and Clinical Relevance: By defining a strict remission phenotype, we identified 3 SNPs to be associated with complete asthma remission, where 2 SNPs have plausible biological relevance in FRS2,CCT,IL1RL1, IL18R1 and IL13. [ABSTRACT FROM AUTHOR]

Clarus Leung,1 Jean Bourbeau,2 Don D Sin,1 Shawn D Aaron,3 J Mark FitzGerald,4 François Maltais,5 Darcy D Marciniuk,6 Denis O’Donnell,7 Paul Hernandez,8 Kenneth R Chapman,9 Brandie Walker,10 Jeremy D Road,4 Liyun Zheng,1 Carl Zou,1 James C Hogg,1 Wan C Tan1 On behalf of the CanCOLD Collaborative Research Group1Centre for Heart Lung Innovation, St Pauls Hospital, The University of British Columbia, Vancouver, BC, Canada; 2Research Institute McGill University Health Centre, McGill University, Montreal, Quebec, Canada; 3The Ottawa Hospital Research Institute, University of Ottawa, Ottawa, Canada; 4Department of Medicine, Vancouver General Hospital, University of British Columbia, Vancouver, Canada; 5Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Quebec, Canada; 6Respiratory Research Centre, University of Saskatchewan, Saskatoon, Canada; 7Department of Medicine, Queen’s University, Kingston, Canada; 8Department of Medicine, Dalhousie University, Halifax, Canada; 9Toronto General Hospital Research Institute, University of Toronto, Toronto, Canada; 10Department of Medicine, University of Calgary (BW), Alberta, CanadaCorrespondence: Wan C TanCentre for Heart Lung Innovation, St. Paul’s Hospital, University of British Columbia, Rm 166, 1081 Burrard Street, Vancouver, B.C, V6Z 1Y6, CanadaTel +1-604-682-2344 ext 62749Fax +1-604-806-9274Email wan.tan@hli.ubc.caPurpose: To determine the spirometric-based prevalence of COPD across different regions in Canada and to evaluate the site heterogeneity of risk factors.Patients and Methods: In this cross-sectional, population-based study, random samples of non-institutionalized adults aged ≥ 40 years were generated by random digit dialling. Participants answered an interviewer-administered questionnaire and performed spirometry before and after bronchodilator administration. COPD was defined as post-bronchodilator FEV1/FVC < 0.70 (fixed ratio, FR) and as FEV1/FVC < 5th percentile (lower limits of normal, LLN). Separate logistic regression models were used to compute the risk (adjusted odds ratio, aOR) for COPD. I2 and Tau2 analyses were used to evaluate heterogeneity.Results: Out of 5176 (95%) participants, 4893 (47% male with mean age 56.6 years (95% confidence interval, 56.0– 57.2)) had spirometry that satisfied ATS criteria. The population prevalence of COPD was 16.2% (95% CI, 14.5– 17.8) by FR and 11.2% (95% CI, 9.7– 12.6) by LLN. Male predominance in prevalence was shown by FR but not by LLN criteria. Patient characteristics associated with an increased risk of COPD included: age (OR 1.56; 95% CI 1.33– 1.84); history of physician-diagnosed asthma (OR 3.30; 95% CI 2.42– 4.49); and childhood hospitalization for respiratory illness (OR 1.81; 95% CI 1.17– 2.80). In terms of smoking-related risk factors, current smoking status had the highest odds ratio (OR 3.49; 95% CI 2.55– 4.80). Variance in prevalence among sites was significantly reduced by adjusting for risk factors in Tau2 analyses. Higher odds of exposure for each risk factor was found in more severe COPD, suggesting that a higher risk could be linked to the development of severe disease.Conclusion: This study reports the population prevalence of COPD in nine urban cities which collectively represent the majority of the Canadian population and demonstrates that heterogeneity in prevalence among sites is substantially explained by variation in associated risk factors for COPD.Keywords: prevalence, heterogeneity, COPD

Mai Tsutsui,1 Firoozeh Gerayeli,1 Don D Sin1,2 1Centre for Heart Lung Innovation, St. Paul’s Hospital, University of British Columbia, Vancouver, BC, Canada; 2Division of Respiratory Medicine, University of British Columbia, Vancouver, BC, CanadaCorrespondence: Don D SinCentre for Heart Lung Innovation, St. Paul’s Hospital, University of British Columbia, 1081 Burrard Street, Vancouver, BC, V6Z 1Y6, CanadaTel +1 604 806 8818Fax +1 604 806 9274Email don.sin@hli.ubc.caAbstract: Pulmonary rehabilitation (PR) is effective in reducing symptoms and improving health status, and exercise tolerance of patients with chronic obstructive pulmonary disease (COPD). The coronavirus disease 19 (COVID-19) pandemic has greatly impacted PR programs and their delivery to patients. Owing to fears of viral transmission and resultant outbreaks of COVID-19, institution-based PR programs have been forced to significantly reduce enrolment or in some cases completely shut down during the pandemic. As a majority of COPD patients are elderly and have multiple co-morbidities including cardiovascular disease and diabetes, they are notably susceptible to severe complications of COVID-19. As such, patients have been advised to stay at home and avoid social contact to the maximum extent possible. This has increased patients’ vulnerability to physical deconditioning, depression, and social isolation. To address this major gap in care, some traditional hospital or clinic-centered PR programs have converted some or all of their learning contents to home-based telerehabilitation during the pandemic. There are, however, some significant barriers to this approach that have impeded its implementation in the community. These include variable access and use of technology (by patients), a lack of standardization of methods and tools for evaluation of the program, and inadequate training and resources for health professionals in optimally delivering telerehabilitation to patients. There is a pressing need for high-quality studies on these modalities of PR to enable the successful implementation of PR at home and via teleconferencing technologies. Here, we highlight the importance of telerehabilitation of patients with COPD in the post-COVID world and discuss various strategies for clinical implementation.Keywords: pulmonary rehabilitation, COVID-19, telerehabilitation, COPD

Background The severity of bronchial hyperresponsiveness ( BHR) is a fundamental feature of asthma. The severity of BHR varies between asthmatics and is associated with lack of asthma control. The mechanisms underlying this trait are still unclear. This study aimed to identify genes associated with BHR severity, using a genomewide association study ( GWAS) on the slope of BHR in adult asthmatics. Methods We performed a GWAS on BHR severity in adult asthmatics from the Dutch Asthma GWAS cohort ( n = 650), adjusting for smoking and inhaled corticosteroid use, and verified results in three other cohorts. Furthermore, we performed e QTL and co-expression analyses in lung tissue. Results In the discovery cohort, one genomewide significant hit located in phosphodiesterase 4D, c AMP-specif ( PDE4D) and 26 SNPs with P-values < 1*10−5 were found. None of our findings replicated in adult and childhood replication cohorts jointly. In adult cohorts separately, rs1344110 in pituitary tumour-transforming 1 interacting protein ( PTTG1 IP) and rs345983 in Mastermind-like 3 ( MAML3) replicated nominally; minor alleles of rs345983 and rs1344110 were associated with less severe BHR and higher lung tissue gene expression. PTTG1 IP showed significant co-expression with pituitary tumour-transforming 1, the binding factor of PTTG1lP, and with vimentin and E-cadherin1. MAML3 co-expressed significantly with Mastermind-like 2 ( MAML2), both involved in Notch signalling. Conclusions PTTG1 IP and MAML3 are associated with BHR severity in adult asthma. The relevance of these genes is supported by the e QTL analyses and co-expression of PTTG1lP with vimentin and E-cadherin1, and MAML3 with MAML2. [ABSTRACT FROM AUTHOR]

Marjan Kerkhof,1 Jaco Voorham,1 Paul Dorinsky,2 Claudia Cabrera,3,4 Patrick Darken,5 Janwillem WH Kocks,1,6 Mohsen Sadatsafavi,7,8 Don D Sin,7,8 Victoria Carter,1 David B Price1,9 1Observational & Pragmatic Research Institute Pte Ltd, Singapore, Singapore; 2AstraZeneca, Durham, NC, USA; 3AstraZeneca, Mölndal, Sweden; 4Department of Medical Epidemiology and Biostatistics, Karolinska Institute, Stockholm, Sweden; 5AstraZeneca, Morristown, NJ, USA; 6General Practitioners Research Institute, Groningen, The Netherlands; 7Respiratory Evaluation Sciences Program, Collaboration for Outcomes Research and Evaluation, University of British Columbia, Vancouver, BC, Canada; 8Centre for Heart Lung Innovation, St. Paul’s Hospital, Vancouver, BC, Canada; 9Academic Primary Care, University of Aberdeen, Aberdeen, UKCorrespondence: David B Price Polwarth Building, Foresterhill, Aberdeen AB25 2ZD, UKTel +65 6962 3627Email dprice@opri.sgIntroduction: Early identification of preventable risk factors of COPD progression is important. Whether exacerbations have a negative impact on disease progression is largely unknown. We investigated whether the long-term occurrence of exacerbations is associated with lung function decline at early stages of COPD.Methods: Patients diagnosed with mild/moderate COPD (obstruction and FEV1% predicted 50– 90%), aged ≥ 35 years, and a smoking history, who had ≥ 6 years of UK electronic medical records after initiation of maintenance therapy were studied. Multilevel mixed-effect linear regression was performed to determine the association between the count of any year in which the patient had ≥ 1 exacerbation over a 6-year period and FEV1 decline, adjusted for sex, age, anthropometrics and smoking habits. Exacerbations were defined as any prescription for an acute oral corticosteroid course and/or lower respiratory-related antibiotics and/or any COPD-related emergency or inpatient hospitalization.Results: Of 11,337 patients included (mean age 65 years; 49% female) 31.6%, 23.3%, 16.6%, 11.6%, 8.1%, 5.3% and 3.4% had 0, 1, 2, 3, 4, 5 and 6 years with ≥ 1 exacerbation. The mean annual FEV1 decline accelerated by 1.50 mL/year (95% Confidence Interval 1.02; 1.98) with every additional year with ≥ 1 exacerbation from 31.0 mL/year in subjects without any exacerbation to 40.0 mL/year in patients experiencing ≥ 1 exacerbation every year. Patients with more years with ≥ 1 exacerbation had a lower mean FEV1 at first diagnosis: 14.7 mL (11.7; 17.8) lower with every additional year with exacerbations. When counting years with ≥ 2 exacerbations, greater effects were observed (2.19 [1.50; 2.88] mL/year excess decline per year with ≥ 2 exacerbations; 16.5 mL [12.1; 20.8] lower FEV1 at diagnosis).Conclusion: Patients who experienced a greater exacerbation burden after initiation of maintenance therapy had worse lung function at diagnosis and a more rapid lung function decline thereafter, which emphasizes the need for better treatment strategies.Keywords: COPD, exacerbations, spirometry, inhalation therapy, observational study

Background Air pollution is a major cause of global morbidity and mortality. Air pollution and aeroallergens aggravate respiratory illness, but the variable effects of air pollutants and allergens in the lung are poorly understood. Objective To determine the effects of diesel exhaust ( DE) and bronchial allergen challenge as single and dual exposures on aspects of innate immunity in the airway as reflected by surfactant protein D ( SPD), myeloperoxidase ( MPO) and club (Clara) cell secretory protein 16 ( CC16) in 18 atopic individuals. Methods In this double-blind, randomized crossover study, atopic individuals were exposed to DE or filtered air, followed by endobronchial allergen or saline 1 hour after inhalational exposure. Bronchoalveolar lavage, bronchial washings, nasal lavage and blood samples were obtained 48 hours after exposures and assayed for CC16, MPO and SPD by ELISA. Results In bronchial samples, the concentration of SPD increased from 53.3 to 91.8 ng/mL after endobronchial allergen, with no additional contribution from DE. MPO also increased significantly in response to allergen (6.8 to 14.7 ng/mL), and there was a small additional contribution from exposure to DE. The concentration of CC16 decreased from 340.7 to 151.0 ng/mL in response to DE, with minor contribution from allergen. These changes were not reflected in nasal lavage fluid or plasma samples. Conclusions and Clinical Relevance These findings suggest that allergen and DE variably influence different aspects of the innate immune response of the lung. SPD and MPO, known markers of allergic inflammation in the lung, are strongly increased by allergen while DE has a minor effect therein. DE induces a loss of CC16, a protective protein, while allergen has a minor effect therein. Results support site- and exposure-specific responses in the human lung upon multiple exposures. [ABSTRACT FROM AUTHOR]