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Rationale: Obstructive lung disease (OLD) pathogenesis includes inhalational (e.g., smoking) and noninhalational mechanisms (e.g., infections). Human immunodeficiency virus (HIV) has been suggested as a novel OLD risk factor. Substantial data have recently emerged about its effects on lung function and structure, especially in low- to middle-income countries and regarding longitudinal lung function. Objectives: To assess the association of HIV infection with OLD, impaired gas exchange, and emphysema. Methods: In this systematic review and meta-analysis, we searched PubMed, Embase, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Web of Science, Scopus, Cumulative Index to Nursing and Allied Health Literature, and Global Index Medicus through April 2023 for controlled and observational studies of people living with and without HIV reporting pulmonary function and/or emphysema. Primary outcomes were OLD by spirometry, gas exchange impairment by diffusing capacity of the lung for carbon monoxide, and visual emphysema by computed tomography. We performed random-effects meta-analyses using odds ratios (ORs) with 95% confidence intervals (CIs). This study was registered in PROSPERO (CRD42021268498). Results: We included 95 publications pertaining to 43 unique studies. HIV was associated with OLD (OR, 1.29; 95% CI, 1.02-1.63), impaired gas exchange (OR, 2.63; 95% CI, 0.96-7.24), emphysema (OR, 1.46; 95% CI, 1.02-2.09), and faster lung function decline. OLD risk was greatest in Africans with HIV. There were no gas exchange or emphysema data from Africa. The certainty of evidence was low to very low, primarily because of studies' observational design. Conclusions: People living with HIV have increased risk for OLD, gas exchange impairment, faster lung function decline, and emphysema. OLD risk in HIV varies regionally. We recommend that both spirometry and diffusing capacity of the lung for carbon monoxide be measured in people living with HIV and respiratory symptoms. Future studies should develop and validate HIV-specific screening and case-finding strategies for chronic lung disease.

Purpose: There are only a limited number of studies in the literature evaluating body awareness, pain perception, and the relationship between clinical parameters and respiratory functions in patients with obstructive lung disease (OLD) and compared with healthy individuals. Therefore, this study aimed to evaluate respiratory functions, pain tolerance, and body awareness in patients with OLD and compare these findings with those of healthy individuals., Methods: The study included 33 patients and 30 healthy individuals. The respiratory function (spirometer), respiratory muscle strength (mouth pressure device), endurance (threshold loading device), pain level and tolerance (short-form McGill Pain Questionnaire and algometer), posture, and body awareness (Body Awareness Questionnaire-BAQ) were evaluated., Results: The pain threshold and tolerance of the biceps, triceps, trapezius, and quadriceps muscles were significantly lower and BAQ scores were higher in patients with OLD compared with healthy individuals (p < .05). There was a significant relationship between FEV 1 (%) and pain tolerance of the triceps (r = 0.371, p = .047) and gastrocnemius muscles (r = 0.419, p = .024); FVC (%) and pain threshold of the gastrocnemius (r = 0.413, p = .023), triceps muscles (r = 0.394, p = .034), and pain tolerance of the gastrocnemius muscle (r = 0.549, p = .002)., Conclusions: Patients with OLD have a marked increase in pain perception and body awareness levels and a decrease in pain threshold and tolerance compared with healthy controls. Future studies should assess the effectiveness of pain management interventions as a part of pulmonary rehabilitation for patients with chronic respiratory diseases., Clinical Implications: Pain management is important for planning pulmonary rehabilitation programmes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)

Introduction: Previous population-based studies, mainly from high-income countries, have shown that a higher forced vital capacity (FVC) is associated with a lower risk of developing cardiometabolic diseases. The aim of this study was to assess the longitudinal association between spirometry measures and the onset of cardiometabolic diseases across sites in low-income, middle-income and high-income countries., Methods: The study population comprised 5916 individuals from 15 countries participating in the Burden of Obstructive Lung Disease baseline and follow-up assessments. Postbronchodilator forced expiratory volume in 1 s (FEV1), FVC and FEV1/FVC were measured at baseline. Participants who reported having doctor-diagnosed hypertension, diabetes, heart disease and stroke at follow-up but not at baseline were considered new cases of these diseases. The association between lung function and the onset of participant-reported cardiometabolic diseases was assessed in each site using regression models, and estimates were combined using random effects meta-analysis. Models were adjusted for sex, age, smoking, body mass index and educational level., Results: Participants with greater per cent predicted FVC were less likely to have new-onset diabetes (OR per 10%=0.91, 95% CI 0.84 to 0.99), heart disease (OR per 10%=0.86, 95% CI 0.80 to 0.92) and stroke (OR per 10%=0.81, 95% CI 0.73 to 0.89) during the follow-up period (mean±SD 9.5±3.6 years). A greater percentage of FEV 1 was associated with a lower risk of onset of heart disease and stroke. No significant association was found between FEV 1 /FVC and onset of reported cardiometabolic diseases, except for a higher risk of diabetes (OR per 10%=1.21, 95% CI 1.08 to 1.35) in participants with higher FEV 1 /FVC., Conclusions: The findings of this study suggest that a low FVC is more important than a low FEV 1 /FVC as a risk factor for developing cardiometabolic diseases. The value of including FVC in risk score models to improve their precision in predicting the onset of cardiometabolic diseases should be explored., Competing Interests: Competing interests: RN declares support from Astra Zenenca related to and the Norwegian Respiratory Society not related to the manuscript. AØR declares support from Boehringer Ingelheim and the Endowment of Timber Merchant A. Delphin and Wife unrelated to the manuscript. PGJB declares support from the Wellcome Trust related to the manuscript. AFSA declares support from the Colt Foundation not related to the manuscript. None of the other authors declare any conflicts of interest., (© Author(s) (or their employer(s)) 2025. Re-use permitted under CC BY. Published by BMJ Group.)

Background: Small airways disease (SAD) is a key risk in developing obstructive lung diseases (OLD). Handgrip strength (HGS) is found to be associated with pulmonary function in populations with lung conditions. Hispanics remain the main workforce in farming industry, but their prevalence of lung conditions remain understudied. Likewise, HGS also remains understudied in Hispanic and farmworker populations. Our study investigated the prevalence of SAD and OLD as well as their associations with HGS among Hispanic farmworkers., Methods: A cross-sectional study analyzed 113 Hispanic farmworkers (54% female) who were screened using pulmonary function tests during annual health fairs in rural Southeastern US from 2013 to 2017. Smoking status was self-reported. SAD was defined as forced expiratory flow at 25-75% predicted of vital capacity (FEF 25-75%predicted ) ≤ 60% per literature and OLD defined as forced expiratory volume in 1 s/ forced vital capacity (FEV1/FVC) ratio < 70% per Global Initiative for Chronic Obstructive Lung Disease criteria. Seated isometric absolute (the sum of both hands) and relative (absolute handgrip strength divided by body mass index) handgrip strengths were collected., Results: 26.5% of subjects had SAD and 15.9% had OLD. 50% of subjects with SAD had OLD while 83% of subjects with OLD had SAD. 13% of overall population smoked. Lower absolute and relative HGS groups had higher prevalence of SAD and OLD. Multivariate linear regression showed that lower absolute and relative HGS were associated with worsened small airway function. Age and FEF 25-75%predicted were associated with FEV1/FVC. Smoking, body mass index, blood pressures, hemoglobin A1C and lipids were not predictors in either model., Conclusions: This is one of the first studies reporting prevalence of pulmonary function in Hispanic farmworkers. Although this population was relatively young and healthy, there was high prevalence of SAD and OLD, which was higher than the overall prevalence in Hispanic population. There were more females subjects with SAD. Most of the subjects with OLD had SAD but not vice versa. Lower HGS levels were associated with worsened pulmonary function, and HGS was a significant predictor of FEF 25-75%predicted , a potential marker for small airway physiology., Competing Interests: Declarations. Ethics approval and consent to participate: Written consent was obtained from each subject with study protocol approved by Institutional Review Board at Augusta University (IRB#Pro00001160). Consent for publication: Not applicable. Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

From the results of well-performed population health studies, we now have excellent data demonstrating that deficits in adult lung function may be present early in life, possibly as a result of developmental disorders, incurring a lifelong risk of obstructive airway diseases such as asthma and chronic obstructive pulmonary disease. Suboptimal fetal development results in intrauterine growth restriction and low birth weight at term (an outcome distinct from preterm complications), which are associated with subsequent obstructive disease. Numerous prenatal exposures and disorders compromise fetal development and these are summarized herein. Various physiological, structural, and mechanical abnormalities may result from prenatal disruption, including changes to airway smooth muscle structure-function, goblet cell biology, airway stiffness, geometry of the bronchial tree, lung parenchymal structure and mechanics, respiratory skeletal muscle contraction, and pulmonary inflammation. The literature therefore supports the need for early life intervention to prevent or correct growth defects, which may include simple nutritional or antioxidant therapy. © 2024 American Physiological Society. Compr Physiol 14:5729-5762, 2024., (Copyright © 2024 American Physiological Society. All rights reserved.)

Introduction: In normal subjects, during tidal breathing, aerosols deposit by settling in small airways. With obstructive lung disease (OLD), collapse of airways during expiration causes turbulence and increased deposition in central airways. High-flow nasal cannula (HFNC) therapy, washing out dead space, may affect deposition mechanisms and drug delivery. This study compared aerosol deposition and airway responsiveness in OLD after traditional and HFNC nebulization therapy. Methods: Twelve subjects with moderate to severe OLD participated in a two-day study. Spirometry was measured pre- and post-aerosol inhalation. On Day 1 (D1) subjects tidally inhaled radiolabeled albuterol ( 99m Tc DTPA) by mouth via AeroTech II, (Biodex. Shirley, NY). Day 2 (D2) inhalation was via HFNC using i-AIRE (InspiRx, Inc. Somerset, NJ). The HFNC system (60 L/m) was infused by syringe pump at 50 mL/h. D2 lung deposition was monitored in real time by gamma camera to match D1. Pre and post heart rate, O 2 sat, and nasopharyngeal deposition (NP) were measured. Mechanistic contributions were modeled using multiple linear regression (MLR) of deposition rate (DR µg/m) as a function of breathing frequency, airway geometry (FEV 1 ), and parenchymal integrity (DLCO). Results: Albuterol lung depositions were matched ( p = 0.13) with D1 central/peripheral (sC/P) ratios 1.99 ± 0.98. Following HFNC, peripheral deposition increased (31% ± 33%, sC/P = 1.51 ± 0.43, p = 0.01). D2/D1% change FVC increased by 16.1 ± 16.7% ( p = 0.003). NP deposition averaged 333% of lung. Heart rate and O 2 sat were unaffected ( p = 0.31, p = 0.63 respectively). DR analysis was markedly different between D1 ( R 2 = 0.82) and D2 ( R 2 = 0.12). Conclusion: In subjects with OLD, HFNC nebulization at 60 L/min was well tolerated and increased peripheral drug delivery. Spirometry significantly improved. Systemic effects were undetected indicating limited nasal absorption. MLR demonstrated that different mechanisms of deposition govern traditional vs HFNC aerosol delivery. Breath-enhanced nebulization via HFNC may provide controllable and effective aerosol therapy in OLD.

Objective: To investigate the correlation between impulse oscillometry system examination indicators and conventional pulmonary ventilation function. Methods: The pulmonary ventilation function data of 10 883 patients from January 1, 2020 to December 31, 2022 at Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology were included. The one-second rate [ratio of forced expiratory volume in the first second (FEV 1 ) to forced vital capacity (FVC)] measured as a percentage of the predicted value was ≥92% for the control group ( n= 3 478) and <92% for the pulmonary obstruction group ( n= 7 405). The obstruction group was subdivided into five groups according to the degree of pulmonary dysfunction: mild group ( n= 3 938),moderate group ( n= 1 142),oderate-severe group ( n= 917),severe group ( n= 737),and extremely severe group ( n= 671). Conventional pulmonary ventilatory function FVC, FEV 1 , one-second rate, and forced expired flow at 50% of FVC (MEF50%), forced expired flow at 75% FVC (MEF25%), maximal mid-expiratory flow (MMEF), peak expiratory flow (PEF), and pulsed oscillation pulmonary function test were detected in both groups of patients. Impedance at 5 Hz (Z5) means total respiratory resistance, resistance at 5 Hz (R5) means total airway resistance, reactance at 5 Hz (X5) indicates the elastic recoil of the peripheral airways, and resistance at 20 Hz (R20) represents resistance of the central airways. R5-R20 reflects resistance in the small airways. Additionally, peripheral resistance (Rp), respiratory resonance frequency (Frex), and area under the reactance curve (Ax) were also measured. Correlation between the indicators of the two groups and the sensitivity and specificity of the impulse oscillometry system parameters for the diagnosis of obstructive pulmonary ventilation dysfunction were analyzed. Results: Pulmonary function force expiratory volume in the first second as a percentage of predicted value (FEV 1 %Pre) [80.10 (54.95,97.10)%],one-second rate [62.43(48.67, 67.02)%],MEF50% [1.33 (0.62,1.97)L/s],MEF25% [0.28 (0.17,0.41)L/s], MMEF [0.85 (0.43,1.29)L/s],and PEF [5.64 (3.73,7.50)]L/s in the obstruction group were significantly lower than those in the control group ( P< 0.05). The differences within the subgroups of the obstruction group were also significant ( P< 0.05). Pulsed oscillation Z5 [0.42 (0.33,0.55)kPa·L -1 ·s -1 ],Rp [0.25 (0.20,0.45)kPa·L -1 ·s -1 ], R5 [0.39 (0.31,0.49)kPa·L -1 ·s -1 ], R20 [0.28 (0.24,0.34)kPa·L -1 ·s -1 ], R5-R20 [0.09 (0.05,0.17)kPa·L -1 ·s -1 ],Frex [16.32 (13.07,20.84)Hz], and Ax [0.67 (0.28,1.64)] indices in the obstruction group were significantly higher than those in the control group. X5 [-0.14 (-0.23, -0.10)kPa·L -1 ·s -1 ] was significantly lower than that in the control group ( P< 0.05). Z5, Rp, X5, R5, R5-R20, Frex, and Ax were statistically significant between different degrees of obstruction in the obstruction group ( P< 0.05). The impulse oscillometry system parameters Z5, Rp, R5, R20, R5-20, Frex, and Ax were negatively correlated with the indices of conventional pulmonary ventilation ( r =-0.21-0.68, P< 0.05), and the parameter X5 was positively correlated with the indices of conventional pulmonary ventilation ( r= 0.41-0.68, P< 0.05). The pulsed oscillation pulmonary function test parameters X5 (58.60%-95.68%) and Ax (57.08%-98.06%) presented the best sensitivity; X5 (86.29%-98.82%), Frex (86.69%-94.71%), and Ax (88.10%-98.53%) displayed the best specificity; and R20 presented the worst sensitivity and specificity. The sensitivity and specificity were slightly better in female patients than in male patients. Conclusion: The technical parameters of the impulse oscillometry system showed significant correlation with relevant indices of conventional pulmonary ventilation function detection. These well reflect the changes of different degrees of pulmonary ventilation function and have greater significance for reference in evaluating the degree of pulmonary function impairment.

Obstructive lung diseases such as bronchial asthma, COPD, and cystic fibrosis are a burden on many patients across the globe. Spirometry is considered the gold standard for diagnosing airflow obstruction, but it can be difficult for pediatric patients to do and requires a lot of effort. As a result, healthcare providers need new, effortless methods to diagnose airway obstructions, particularly in young children and individuals unable to perform the spirometry maneuver. The forced oscillation technique is a modern method requiring only tidal breathing combined with the application of external, source of low-amplitude oscillations to evaluate the respiratory system's response. It might be essential for identifying early respiratory changes caused by smoking, childhood asthma, and may prove more sensitive than spirometry in identifying peripheral airway disturbances or evaluating the long-term success of therapy. This review describes the methodology and the indications for the forced oscillation technique and outlines its relevance in clinical practice., (This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Objective: To understand the prevalence rate of obstructive pulmonary dysfunction in workers exposed to silica dust and analyze its risk factors, so as to provide reference for the formulation of diagnostic criteria for chronic obstructive pulmonary disease caused by occupational dust., Methods: Data collection and structured questionnaire were used to collect the data of 2064 workers exposed to silica dust who underwent health examination in Hunan Occupational Disease Prevention and Control Hospital and Yuanling Second People's Hospital from January 1, 2021 to June 30, 2022. The prevalence rate of obstructive pulmonary ventilation dysfunction was analyzed and the risk factors were analyzed., Results: The prevalence rate of obstructive pulmonary ventilation dysfunction (FEV1/FVC < 70%) was 2.3% in 2064 silica dust exposed workers. The prevalence of restrictive pulmonary ventilation dysfunction (FVC/Pre < 80%) was 8.1%. The prevalence of obstructive pulmonary ventilation dysfunction in the high level exposure group was higher than that in the low level exposure group, 8.2 vs0.9% (P < 0.05). The rate of obstructive pulmonary ventilation dysfunction in female group was higher than that in male group (5.3% vs. 1.7%, p = 0.00). Workers with obstructive pulmonary dysfunction were older and worked longer than workers without obstructive pulmonary dysfunction, but there was no statistical difference. Multivariate regression analysis showed that high exposure level was a risk factor for obstructive pulmonary ventilation dysfunction in silica dust exposed workers (P < 0.05). Females were the risk factors for obstructive pulmonary ventilation dysfunction (P < 0.05)., Conclusion: Silica dust exposure can cause obstructive pulmonary ventilation dysfunction and lead to chronic obstructive pulmonary disease. High level of exposure is a risk factor for obstructive pulmonary ventilation dysfunction. Women exposed to dust are more prone to obstructive pulmonary ventilation dysfunction than men. Early diagnosis of chronic obstructive pulmonary disease caused by silica dust and timely intervention measures are very important to delay the decline of lung function and protect the health of workers., (© 2024. The Author(s).)

Background: For many patients with lung disease the only proven intervention to improve survival and quality of life is lung transplantation (LTx). Esophageal dysmotility and gastroesophageal reflux (GER) are common in patients with respiratory disease, and often associate with worse prognosis following LTx. Which, if any patients, should be excluded from LTx based on esophageal concerns remains unclear. Our aim was to understand the effect of LTx on esophageal motility diagnosis and examine how this and the other physiological and mechanical factors relate to GER and clearance of boluses swallowed., Methods: We prospectively recruited 62 patients with restrictive (RLD) and obstructive (OLD) lung disease (aged 33-75 years; 42 men) who underwent high resolution impedance manometry and 24-h pH-impedance before and after LTx., Key Results: RLD patients with normal motility were more likely to remain normal (p = 0.02), or if having abnormal motility to change to normal (p = 0.07) post-LTx than OLD patients. Esophageal length (EL) was greater in OLD than RLD patients' pre-LTx (p < 0.001), reducing only in OLD patients' post-LTx (p = 0.02). Reduced EL post-LTx associated with greater contractile reserve (r = 0.735; p = 0.01) and increased likelihood of motility normalization (p = 0.10). Clearance of reflux improved (p = 0.01) and associated with increased mean nocturnal baseline impedance (p < 0.001) in RLD but not OLD. Peristaltic breaks and thoraco-abdominal pressure gradient impact both esophageal clearance of reflux and boluses swallowed (p < 0.05)., Conclusions and Inferences: RLD patients are more likely to show improvement in esophageal motility than OLD patients post-LTx. However, the effect on GER is more difficult to predict and requires other GI, anatomical and pulmonary factors to be taken into consideration., (© 2024 The Authors. Neurogastroenterology & Motility published by John Wiley & Sons Ltd.)

Introduction: There is no clear consensus as to what constitutes an obstructive ventilatory impairment (OVI) in pediatric populations., Aim: To determine the percentage of children/adolescents having an OVI among those addressed for spirometry after taking into account the definitions advanced by some international scholarly societies [British Columbia (BC), British thoracic-society (BTS), Canadian thoracic society (CTS), European respiratory society and American thoracic society (ERS-ATS), global initiative for asthma (GINA), Irish college of general practitioners (ICGP), national asthma council (NAC), national institute of clinical excellence (NICE), Société de pneumologie de langue française, Société pédiatrique de pneumologie et allergologie (SPLF-SP2A), and South African thoracic society (SATS)]., Methods: This bi-centric cross-sectional study involves two medical structures in Sousse/Tunisia, and will encompass children/adolescents aged 6-18 years. A medical questionnaire will be administered, clinical and anthropometric data will be collected, and the spirometric data will be measured by two spirometers. The following six definitions of OVI will be applied: i) GINA: Forced expiratory volume in 1 second (FEV1) < 80% and a FEV1/forced vital capacity (FVC) ≤ 0.90; ii) ICGP: FEV1/FVC < 0.70; iii) ERS-ATS or BTS or SATS or SPLF-SP2A or NAC: FEV1/FVC z-score < -1.645; iv) NICE: FEV1/FVC < 0.70 or FEV1/FVC z-score < -1.645; v) CTS: FEV1/FVC < 0.80 or a FEV1/FVC z-score < -1.645; and vi) ERS: "FEV1 z-score or FEV1/FVC z-score" < -1.645 or "FEV1 or FEV1/FVC" < 0.80., Expected Results: The percentage of children/adolescents having an OVI will significantly vary between the six definitions., Conclusion: The frequency of OVI in a pediatric population will depend on the definition chosen.

Background: Chronic obstructive pulmonary disease (COPD) is a leading cause of global mortality. In high-income settings, the presence of cardiovascular disease among people with COPD increases mortality and complicates longitudinal disease management. An estimated 26 million people are living with COPD in sub-Saharan Africa, where risk factors for co-occurring pulmonary and cardiovascular disease may differ from high-income settings but remain uncharacterized. As non-communicable diseases have become the leading cause of death in sub-Saharan Africa, defining multimorbidity in this setting is critical to inform the required scale-up of existing healthcare infrastructure., Methods: We measured lung function and carotid intima media thickness (cIMT) among participants in the UGANDAC Study. Study participants were over 40 years old and equally divided into people living with HIV (PLWH) and an age- and sex-similar, HIV-uninfected control population. We fit multivariable linear regression models to characterize the relationship between lung function (forced expiratory volume in one second, FEV 1 ) and pre-clinical atherosclerosis (cIMT), and evaluated for effect modification by age, sex, smoking history, HIV, and socioeconomic status., Results: Of 265 participants, median age was 52 years, 125 (47%) were women, and 140 (53%) were PLWH. Most participants who met criteria for COPD were PLWH (13/17, 76%). Median cIMT was 0.67 mm (IQR: 0.60 to 0.74), which did not differ by HIV serostatus. In models adjusted for age, sex, socioeconomic status, smoking, and HIV, lower FEV 1 was associated with increased cIMT (β = 0.006 per 200 mL FEV 1 decrease; 95% CI 0.002 to 0.011, p = 0.01). There was no evidence that age, sex, HIV serostatus, smoking, or socioeconomic status modified the relationship between FEV 1 and cIMT., Conclusions: Impaired lung function was associated with increased cIMT, a measure of pre-clinical atherosclerosis, among adults with and without HIV in rural Uganda. Future work should explore how co-occurring lung and cardiovascular disease might share risk factors and contribute to health outcomes in sub-Saharan Africa., (© 2021. The Author(s).)

The association between airflow obstruction and bronchial dilation has been researched in bronchiectasis. However, the impact of bronchial wall thickening on airflow obstruction has not been thoroughly investigated. This study assessed the underlying mechanism of airflow obstruction in bronchiectasis due to abnormal bronchial wall thickening using oscillometry. A total of 98 patients with bronchiectasis were retrospectively reviewed. At the time of diagnosis, spirometric and oscillometric parameters, high-resolution computed tomography scores, and clinical characteristics were collected. The bronchial diameter, bronchial wall thickness, and extent of emphysema were evaluated semi-quantitatively. Correlations between patient data and characteristics were analyzed. Thirty-three patients with airflow obstruction showed higher respiratory resistance, more negative respiratory reactance (Xrs) at 5 Hz (X5), and higher bronchial wall thickness score than those without airflow obstruction. The bronchial wall thickness score negatively affected forced expiration volume in 1 s /forced vital capacity and X5. Abnormal bronchial wall thickening might make Xrs more negative and progress airflow obstruction in bronchiectasis., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Background: Multiple breath washout (MBW) using sulfur hexafluoride (SF 6 ) has the potential to reveal ventilation heterogeneity which is frequent in patients with obstructive lung disease and associated small airway dysfunction. However, reference data are scarce for this technique and mostly restricted to younger cohorts. We therefore set out to evaluate the influence of anthropometric parameters on SF 6 -MBW reference values in pulmonary healthy adults., Methods: We evaluated cross-sectional data from 100 pulmonary healthy never-smokers and smokers (mean 51 (SD 20), range 20-88 years). Lung clearance index (LCI), acinar (S acin ) and conductive (S cond ) ventilation heterogeneity were derived from triplicate SF 6 -MBW measurements. Global ventilation heterogeneity was calculated for the 2.5% (LCI 2.5 ) and 5% (LCI 5 ) stopping points. Upper limit of normal (ULN) was defined as the 95th percentile., Results: Age was the only meaningful parameter influencing SF 6 -MBW parameters, explaining 47% (CI 33% to 59%) of the variance in LCI, 32% (CI 18% to 47%) in S acin and 10% (CI 2% to 22%) in S cond . Mean LCI increases from 6.3 (ULN 7.4) to 8.8 (ULN 9.9) in subjects between 20 and 90 years. Smoking accounted for 2% (CI 0% to 8%) of the variability in LCI, 4% (CI 0% to 13%) in S acin and 3% (CI 0% to 13%) in S cond ., Conclusion: SF 6 -MBW outcome parameters showed an age-dependent increase from early adulthood to old age. The effect was most pronounced for global and acinar ventilation heterogeneity and smaller for conductive ventilation heterogeneity. No influence of height, weight and sex was seen. Reference values can now be provided for all important SF 6 -MBW outcome parameters over the whole age range., Trial Registration Number: NCT04099225., Competing Interests: Competing interests: The following financial activities outside the submitted work exist: FT received travel support from Actelion, Berlin Chemie, Boehringer Ingelheim, Chiesi, Novartis, Mundipharma and TEVA, as well as speaker or consultation fees from AstraZeneca, Berlin Chemie, Boehringer Ingelheim, Bristol-Myers Squibb, Chiesi, GlaxoSmithKline, Roche, Novartis and Sanofi-Aventis. JoS received travel support and speaker fees from Boehringer Ingelheim, GlaxoSmithKline, Novartis and Roche. MB received speaker or consultation fees from Bayer, Boehringer Ingelheim, Daiichi Sankyo, Impulse Dynamics and Zoll Medical. IA received travel support as well as speaker or consultation fees from Abiomed, Bayer, Boehringer Ingelheim and St Jude Medical., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: While tuberculosis is considered a risk factor for chronic obstructive pulmonary disease, a restrictive pattern of pulmonary impairment may actually be more common among tuberculosis survivors. We aimed to determine the nature of pulmonary impairment before and after treatment among people with HIV and tuberculosis and identify risk factors for long-term impairment., Methods: In this prospective cohort study conducted in South Africa, we enrolled adults newly diagnosed with HIV and tuberculosis who were initiating antiretroviral therapy and tuberculosis treatment. We measured lung function and symptoms at baseline, 6, and 12 months. We compared participants with and without pulmonary impairment and constructed logistic regression models to identify characteristics associated with pulmonary impairment., Results: Among 134 participants with a median CD4 count of 110 cells/μl, 112 (83%) completed baseline spirometry at which time 32 (29%) had restriction, 13 (12%) had obstruction, and 9 (7%) had a mixed pattern. Lung function was dynamic over time and 30 (33%) participants had impaired lung function at 12 months. Baseline restriction was associated with greater symptoms and with long-term pulmonary impairment (adjusted odds ratio 5.44, 95% confidence interval 1.16-25.45), while baseline obstruction was not (adjusted odds ratio 1.95, 95% confidence interval 0.28-13.78)., Conclusions: In this cohort of people with HIV and tuberculosis, restriction was the most common, symptomatic, and persistent pattern of pulmonary impairment. These data can help to raise awareness among clinicians about the heterogeneity of post-tuberculosis pulmonary impairment, and highlight the need for further research into mediators of lung injury in this vulnerable population.

Noonan syndrome is a relatively common genetic disorder and the second most common cause of congenital heart disease after trisomy 21. The spectrum of cardiac anomalies in Noonan syndrome typically involves pulmonary valve stenosis occasionally in conjunction with hypertrophic cardiomyopathy. Mitral valve involvement is a rare finding in Noonan syndrome and is most commonly associated with either mitral valve prolapse or abnormal valvular insertion causing left ventricular outflow tract obstruction. Patients with Noonan syndrome typically have preserved fertility and, given the success of cardiac surgery and medical management of heart failure in this population, are beginning to present more commonly as parturients in adulthood. Maternal physiologic changes during pregnancy introduce an added complexity to hemodynamic management and anesthetic considerations during labor and delivery. In this article, we present a case of a patient with Noonan syndrome with severe mitral stenosis, pulmonary valve insufficiency, and severe restrictive and obstructive pulmonary disease who presented preterm for delivery due to increased dyspnea at rest. Here we review the pathophysiology behind Noonan syndrome and peripartum management strategies in a patient with severe combined cardiac and pulmonary disease.

Objectives: Chronic obstructive pulmonary disease and silicosis are associated with exposure to crystalline silica. We determined the exposure to respirable crystalline silica and estimated exposure-response relationships between cumulative exposure and pulmonary function in outdoor rock drillers., Methods: 136 rock drillers and 48 referents were recruited from three heavy construction companies. 98 air samples were collected by personal sampling for determination of respirable particulate matter and crystalline silica. Information about individual job tasks, type of drilling equipment and years of exposure in different job categories was obtained by interview. Cumulative exposure to crystalline silica was calculated for all workers. Pulmonary function was assessed by spirometry. A subgroup of 39 subjects with high cumulative exposure to crystalline silica underwent high-resolution computed tomography (HRCT)., Results: Cumulative exposure (mean (min-max)) to crystalline silica was 0.69 mg٠years m -3 (0.01-5.89) in the exposed group. Mean time of exposure among rock drillers was 10.7 years (1-42). Compared with referents, the rock drillers had a lower forced expiratory volume in one second/forced vital capacity ratio (79.4 vs 81.4, p<0.05) and maximal mid-expiratory flow% (85.6 vs 93.9, p<0.05). Further, by stratifying the exposed workers into three equally large groups, a dose-response relationship was demonstrated in the highest exposed group, also in never smokers, at a mean cumulative exposure of 21.7 years at 0.08 mg٠m -3 /years. Silicosis was not detected in HRCT, but other patterns of fibrosis and emphysema were seen., Conclusions: Outdoor rock drillers exposed to crystalline silica had significantly lower pulmonary function than referents, and signs of airflow obstruction. Silicosis was not detected., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2020. No commercial re-use. See rights and permissions. Published by BMJ.)

Asthma and COPD make up the majority of obstructive airways diseases (OADs), which affects ∼11 % of the population. The main drugs used to treat OADs have not changed in the past five decades, with advancements mainly comprising variations on existing treatments. The recent biologics are beneficial to only specific subsets of patients. Part of this may lie in our inability to adequately characterise the tremendous heterogeneity in every aspect of OAD. The field is currently moving towards the concept of personalised medicine, based on a focus on treatable traits that are objective, measurable and modifiable. We propose extending this concept via the use of emerging clinical tools for comprehensive physiological phenotyping. We describe, based on published data, the evidence for the use of functional imaging, gas washout techniques and oscillometry, as well as potential future applications, to more comprehensively assess and predict treatment response in OADs. In this way, we hope to demonstrate how physiological phenotyping tools will improve the way in which drugs are prescribed, but most importantly, will facilitate development of new drugs for OADs., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Background: Airway clearance techniques (ACTs) are an important aspect of the treatment of children with chronic obstructive lung diseases. Unfortunately, a sound evidence base is lacking and airway clearance strategies are largely based on clinical expertise. One of the reasons for the limited evidence is the lack of appropriate outcome measures specifically related to the effectiveness of ACTs. This review discusses all outcome measures applied in previous research in the pediatric population to provide a baseline for future studies., Data Sources: A systematic literature search was performed in PubMed, Web of Science and EMBASE databases. Search terms included chronic obstructive lung diseases and ACTs., Study Selection: Studies were independently selected by the investigators according to the eligibility criteria. After screening, 49 articles remained for further analysis., Results and Conclusions: Data are summarized according to the type of outcome measure. 48 (98%) studies performed pulmonary function tests, 19 (39%) assessed expectorated sputum, 10 (20%) parameters related to disease exacerbation, 8 (16%) oxygenation, 8 (16%) patient-reported outcomes, 5 (10%) exercise capacity and 5 (10%) applied imaging techniques. The synthesis of results showed a high discrepancy between studies due to differences in study design, population and the application of techniques. Since no 'gold standard' method could be identified, a combination of different outcome measures is recommended to gain a better understanding and to identify the potential effects of ACTs. An overview of important considerations has been provided to assist researchers in their choice of outcomes in future studies.

Spirometry is recommended in symptomatic smokers to identify obstructive lung diseases. However, it is unknown whether there are certain characteristics that can be used to identify the individual risk of developing obstructive lung diseases. The aim of this study was to examine the association between lung function in adults and burden of lung diseases throughout 27 years of follow-up. We performed a cohort study among individuals aged 30-49 years at baseline (1991). Spirometry measurements were divided into three groups: (1) FEV 1 /FVC < 70, (2) FEV 1 /FVC: 70-75, (3) FEV 1 /FVC > 75 (reference). Using negative binominal regression, the burden of lung diseases was measured by contacts to general practice, hospitalisations, redeemed respiratory medicine and socioeconomic parameters between 1991 and 2017. A total of 905 citizens were included; mean age of 40.3 years, 47.5% were males and 51.2% were smokers at baseline. The group with an FEV 1 /FVC: 70-75 received more respiratory medicine (IRR = 3.37 (95% CI: 2.69-4.23)), had lower income (IRR = 0.96 (95% CI: 0.93-0.98)), and had more contacts to general practice (IRR = 1.14 (95% CI: 1.07-1.21)) and hospitals for lung diseases (IRR = 2.39 (95% CI: 1.96-5.85)) compared to the reference group. We found an association between lung function and the future burden of lung diseases throughout 27 years of follow-up. In particular, adults with an FEV 1 /FVC: 70-75 need extra attention in the case finding.

Previous studies demonstrated spontaneous type 2 airway inflammation with eosinophilia in juvenile Scnn1b (sodium channel, non-voltage-gated 1, β-subunit)-transgenic ( Scnn1b -Tg) mice with muco-obstructive lung disease. IL-1 receptor (IL-1R) signaling has been implicated in allergen-driven airway disease; however, its role in eosinophilic inflammation in muco-obstructive lung disease remains unknown. In this study, we examined the role of IL-1R signaling in the development of airway eosinophilia and type 2 inflammation in juvenile Scnn1b -Tg mice. We determined effects of genetic deletion of Il1r1 (IL-1 receptor type I) on eosinophil counts, transcript levels of key type 2 cytokines, markers of eosinophil activation and apoptosis, and tissue morphology in lungs of Scnn1b -Tg mice at different time points during neonatal development. Furthermore, we measured endothelial surface expression of intercellular adhesion molecule 1 (ICAM-1), an integrin involved in eosinophil transendothelial migration, and determined effects of eosinophil depletion using an anti-IL-5 antibody on lung morphology. Lack of IL-1R reduced airway eosinophilia and structural lung damage, but it did not reduce concentrations of type 2 cytokines and associated eosinophil activation in Scnn1b -Tg mice. Structural lung damage in Scnn1b -Tg mice was also reduced by eosinophil depletion. Lack of IL-1R was associated with reduced expression of ICAM-1 on lung endothelial cells and reduced eosinophil counts in lungs from Scnn1b -Tg mice. We conclude that IL-1R signaling is implicated in airway eosinophilia independent of type 2 cytokines in juvenile Scnn1b -Tg mice. Our data suggest that IL-1R signaling may be relevant in the pathogenesis of eosinophilic airway inflammation in muco-obstructive lung diseases, which may be mediated in part by ICAM-1-dependent transmigration of eosinophils into the lungs.

Objective: To evaluate the relationship that the difference between slow vital capacity (SVC) and FVC (ΔSVC-FVC) has with demographic, clinical, and pulmonary function data., Methods: This was an analytical cross-sectional study in which participants completed a respiratory health questionnaire, as well as undergoing spirometry and plethysmography. The sample was divided into two groups: ΔSVC-FVC ≥ 200 mL and ΔSVC-FVC < 200 mL. The intergroup correlations were analyzed, and binomial logistic regression analysis was performed., Results: The sample comprised 187 individuals. In the sample as a whole, the mean ΔSVC-FVC was 0.17 ± 0.14 L, and 61 individuals (32.62%) had a ΔSVC-FVC ≥ 200 mL. The use of an SVC maneuver reduced the prevalence of nonspecific lung disease and of normal spirometry results by revealing obstructive lung disease (OLD). In the final logistic regression model (adjusted for weight and body mass index > 30 kg/m2), OLD and findings of air trapping (high functional residual capacity and a low inspiratory capacity/TLC ratio) were predictors of a ΔSVC-FVC ≥ 200 mL. The chance of a bronchodilator response was found to be greater in the ΔSVC-FVC ≥ 200 mL group: for FEV1 (OR = 4.38; 95% CI: 1.45-13.26); and for FVC (OR = 3.83; 95% CI: 1.26-11.71)., Conclusions: The use of an SVC maneuver appears to decrease the prevalence of nonspecific lung disease and of normal spirometry results. Individuals with a ΔSVC-FVC ≥ 200 mL, which is probably the result of OLD and air trapping, are apparently more likely to respond to bronchodilator administration.

Bronchodilators, including long-acting muscarinic antagonists (LAMAs), improve airflow limitation and lung hyperinflation in patients with chronic obstructive pulmonary disease (COPD). While bronchodilators increase airway caliber and deflate the lungs, little is known about the effects of the local interaction between airway dilation and lung deflation on functional improvements resulting from bronchodilator therapy. This study aimed to explore whether lung deflation with increased airway volume in the upper and lower lung regions would produce different physiological responses to LAMA therapy. Using the clinical data of 41 patients with COPD who underwent spirometry and inspiratory computed tomography (CT) before and 1 year after LAMA treatment, we measured the 1-year change in the airway tree to lung volume percentage ratio (AWV%) for the right upper, middle, and lower lobes (RUL, RML, and RLL) and the left upper and lower lobes (LUL and LLL), and total airway count (TAC) identifiable on CT in relation to the forced expiratory volume in 1 s (FEV 1 ). The results showed that LAMA treatment significantly increased the FEV 1 and AWV% of the RUL, RML, RLL, LUL, and LLL. Increased AWV% in the RLL and LLL, but not in the RUL and LUL, was correlated with increased FEV 1 . In the multivariate analysis, the increased AWV% in the RLL was associated with the increased FEV 1 independent of the change in TAC in the RLL after treatment. This is the first study to show that the physiological improvements after bronchodilator treatment in COPD could be mainly due to the combination of regional deflation and increased airway volume of the lower lobes., (© 2019 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.)

Pulmonary delivery of active drugs has been applied for the treatment of obstructive lung diseases, including asthma, chronic obstructive pulmonary disease and cystic fibrosis, for several decades and has achieved progress in symptom management by bronchodilator inhalation. However, substantial progress in anti-inflammation, prevention of airway remodeling and disease progression is limited, since the majority of the formulation strategies focus only on particle deposition, which is insufficient for pulmonary delivery of the drugs. The lack of knowledge on lung absorption barriers in obstructive lung diseases and on pathogenesis impedes the development of functional formulations by rational design. In this review, we describe the physiological structure and biological functions of the barriers in various regions of the lung, review the pathogenesis and functional changes of barriers in obstructive lung diseases, and examine the interaction of these barriers with particles to influence drug delivery efficiency. Subsequently, we review rational particle design for overcoming lung barriers based on excipients selection, particle size and surface properties, release properties and targeting ability. Additionally, useful particle fabrication strategies and commonly used drug carriers for pulmonary delivery in obstructive lung diseases are proposed in this article., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Patients with pulmonary arterial hypertension (PAH) usually die from progressive right ventricular failure. Mechanical complications due to pulmonary artery (PA) enlargement are rare and include tracheobronchial and left main coronary artery compression, and PA dissection. A 62-year-old female with PAH was seen in our office for follow-up. During the evaluation, spirometry was performed, which revealed a severe obstructive ventilatory limitation. Subsequent workup identified compression of bilateral mainstem bronchi from the dilated PA as the aetiology for the abnormal spirometry. Very few cases of this rare complication have been reported in the literature. A significant dilation of the PA is necessary (>4 cm) for the occurrence of these complications. Dilation of PA is an independent risk factor for sudden unexpected death in patients with PAH., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

Inborn errors of metabolism (IEMs) whilst individually rare, as a group constitute a field which is increasingly demands on pulmonologists. With the advent of new therapies such as enzyme replacement and gene therapy, early diagnosis and treatment of these conditions can impact on long term outcome, making their timely recognition and appropriate investigation increasingly important. Conversely, with improved treatment, survival of these patients is increasing, with the emergence of previously unknown respiratory phenotypes. It is thus important that pulmonologists are aware of and appropriately monitor and manage these complications. This review aims to highlight the respiratory manifestations which can occur. It isdivided into conditions resulting primarily in obstructive airway and lung disease, restrictive lung disease such as interstitial lung disease or pulmonary alveolar proteinosis and pulmonary hypertension, whilst acknowledging that some diseases have the potential to cause all three. The review focuses on general phenotypes of IEMs, their known respiratory complications and the basic metabolic investigations which should be performed where an IEM is suspected., (Crown Copyright © 2019. Published by Elsevier Ltd. All rights reserved.)

To investigate the difference of clinical characteristics between chronic obstructive pulmonary disease (COPD) patients with the frequent exacerbators with chronic bronchitis (FE-CB) phenotype and those with the asthma-COPD overlap syndrome (ACO) phenotype.We searched CNKI, Wan Fang, Chongqing VIP, China Biology Medicine disc, PubMed, Cochrane Library, and EMBASE databases for studies published as of April 30, 2019. All studies that investigated COPD patients with the FE-CB and ACO phenotypes and which qualified the inclusion criteria were included. Cross-sectional/prevalence study quality recommendations were used to measure methodological quality. RevMan5.3 software was used for meta-analysis.Ten studies (combined n = 4568) qualified the inclusion criteria. The FE-CB phenotype of COPD was associated with significantly lower forced vital capacity percent predicted (mean difference [MD] -9.05, 95% confidence interval [CI] [-12.00, -6.10], P < .001, I = 66%), forced expiratory volume in 1 second (FEV1) (MD -407.18, 95% CI [-438.63, -375.72], P < .001, I = 33%), forced expiratory volume in 1 second percent predicted (MD -9.71, 95% CI [-12.79, -6.63], P < .001, I = 87%), FEV1/forced vital capacity (MD -5.4, 95% CI [-6.49, -4.30], P < .001, I = 0%), and body mass index (BMI) (MD -0.81, 95% CI [-1.18, -0.45], P < .001, I = 44%) as compared to the ACO phenotype. However, FE-CB phenotype was associated with higher quantity of cigarettes smoked (pack-years) (MD 6.45, 95% CI [1.82, 11.09], P < .001, I = 73%), COPD assessment test score (CAT) (MD 4.04, 95% CI [3.46, 4.61], P < .001, I = 0%), mMRC score (MD 0.54, 95% CI [0.46, 0.62], P < .001, I = 34%), exacerbations in previous year (1.34, 95% CI [0.98, 1.71], P < .001, I = 68%), and BMI, obstruction, dyspnea, exacerbations (BODEx) (MD 1.59, 95% CI [1.00, 2.18], P < .001, I = 86%) as compared to the ACO phenotype.Compared with the ACO phenotype, COPD patients with the FE-CB phenotype had poorer pulmonary function, lower BMI, and higher CAT score, quantity of cigarettes smoked (pack-years), exacerbations in previous year, mMRC score, and BODEx.This study is an analysis of published literature, which belongs to the second study. Therefore, this study does not require the approval of the ethics committee. The findings will be disseminated through a peer-reviewed journal publication or conference presentation.

Hydatid and alveolar cysts are formed by the helminths Echinococcus granulosus and Echinococcus multilocularis , respectively, which are endemic to pastoral areas, and are more commonly found in South America, the Mediterranean, Russia, and China. Hydatid cysts can cause bacteremia, form abscesses, or cause mass effect by compressing surrounding organs. Strategies to prevent such complications include benzimidazoles, surgical resection, and Puncture, Aspiration, Injection and Re-aspiration (PAIR) procedure. A 71-year-old Egyptian man with remote history of Echinococcus infection one year status post PAIR procedure, presented with dyspnea on exertion. On exam, the patient had a palpable right upper quadrant mass. The patient had a known small hydatid liver cyst on prior ultrasound, however repeat imaging showed growth to 15×19×14cm, with right hemidiaphragm elevation, compressive atelectasis, and compression of the right atrium. He had no peripheral eosinophilia and negative echinococcal serology, consistent with remote infection. The patient underwent repeat PAIR procedure and 3L of serous fluid was drained from the cyst. Fluid analysis was negative for scolices, cysts or hooklets. His symptoms improved; however the cyst re-accumulated 1 month later. Total cystectomy was performed surgically by hepatic wedge resection, with permanent improvement in symptoms. This case is a rare example of Echinococcus infection causing significant respiratory morbidity requiring repeated invasive procedures and surgery, in the setting of inactive disease., Competing Interests: None of the authors identify any conflict of interest.

Pre-existing pulmonary disease may affect treatment choices, toxicity, and survival of patients with multiple myeloma (MM). However, data on the prognostic value of pulmonary function tests (PFTs) in myeloma patients' outcome, at the time of initial assessment of newly diagnosed patients, are scarce. Here, we prospectively performed PFTs in 121 newly diagnosed MM patients, before initiation of treatment, and we evaluated possible associations of lung function with their outcomes. Fifty-four patients (44.63%) had either obstructive or restrictive pulmonary function defects, even among those not reporting a history of lung disease. The survival was significantly worse in those with obstructive pulmonary defect (median OS 32.8 months) vs. those with restrictive (median OS 52.5 months) or normal lung function (median not reached, 3-year survival 76%) (p = 0.013), independently of other myeloma-related factors. Forced vital capacity (FVC) (lt) (p = 0.012), forced expiratory volume in 1 s (FEV1) (lt) (p = 0.018), peak expiratory flow (PEF) (lt/min) (p = 0.008), carbon monoxide diffusion capacity (DLCO) (p = 0.012), and expiratory/inspiratory pressures (Pe) (kPa) (p = 0.032)/(Pi) (kPa) (p = 0.023) were significantly associated with OS. Myeloma-related factors associated with survival included ISS stage (p = 0.008), hypercalcemia (p = 0.064), and high-risk cytogenetics (p = 0.004). In the multivariate analysis, only the presence of high-risk cytogenetics and presence of either or both PEF and DLCO < 65% of predicted were independent prognostic factors. We conclude that PEF and DLCO could be useful in the initial assessment of newly diagnosed MM patients as significant predictors of survival. Further research is needed to evaluate if respiratory screening should be included in the routine initial evaluation of myeloma patients, despite the presence or absence of respiratory symptoms or abnormal clinical respiratory examination.

Objective: To examine whether the parameters of impedance measured by the broadband frequency forced oscillation technique (FOT) were reflected by changes in lung compliance induced by emphysema and fibrosis, we retrospectively compared the parameters of FOT and pulmonary functions, including static lung compliance (Cst), in obstructive lung disease (OLD) and interstitial lung disease (ILD). Patients and methods: The data of 18 patients with OLD (16 with COPD, two with asthma COPD overlap), 11 with ILD, and 24 healthy volunteers, whose respiratory impedance was measured using a MostGraph-01 and other pulmonary functions including Cst and lung resistance (R L ) were measured on the same day and were retrospectively collected and compared. Results: The parameters of resistance, reactance, and resonant frequency showed good correlations with ventilation unevenness ( r =0.63, -0.89, 0.77, respectively) and lung elastic resistance ( r =0.59, -0.80, 0.73, respectively) in all groups (N=53). These indices were significant determinants of increased respiratory resistance and more negative shift of respiratory reactance (Xrs) at lower frequency ( P <0.001). Decreased functional residual capacity was also a determinant of Xrs at 5 Hz (X5) ( P <0.05). The differences in mean X5 in the expiratory phase relative to those in the inspiratory phase (within-breath changes in X5) were associated with airflow obstruction ( P <0.002) and lung elastic resistance ( P <0.001). However, no significant correlations between Cst and any parameters of respiratory impedance were observed. Conclusions: These findings suggest that the impedance parameters measured by FOT are reflected by airway obstruction, ventilation unevenness, and lung resistance, but hardly reflected by changes in lung compliance due to emphysema or fibrosis in both CLD and ILD., Competing Interests: Prof. Dr. Keisaku Fujimoto reports grants from Koganei Corporation, Murata Manufacturing Co., LTD., Seiko Epson Corporation, Denso Corporation, grants and personal fees from Nippon Boehringer Ingelheim Co., Ltd., personal fees from Astellas Pharma Inc., AstraZeneca K.K., Fukuda Denshi Co., Ltd, Fukuda Lifetec Co., Ltd., Japan Association for the Advancement of Medical Equioment, Japan Respiratory Society, Kyorin Pharmaceutical Co., Ltd, Meiji Seika Pharma Co., Ltd., MSD K.K., Novartis Pharma K.K., Teijin Home Healthcare Limited, and Teijin Pharma Limited, outside the submitted work. The authors report no other conflicts of interest in this work.

Objective: PANDAS are known as the spectrum of autoimmune pathologies related to a previous or current infection by group A beta-hemolytic streptococcus (SBEGA), dealing with several neuropsychiatric manifestations that mainly affect pediatric age. The main features consist of behavioral disease or movement disease characterized by acute-onset, presenting especially through infant period or adolescence. Specific manifestations, occurring during the progression of the disease, are the presence of otorhinolaryngologic symptoms (ENT) and orofacial movement disorders associated with temporomandibular joint pain., Patients and Methods: We enrolled 130 children (5-15 years) with a clinical diagnosis of PANDAS between 2012 and 2018. Participants were assessed using ENT specific parameters, PSG to examine respiratory disorders and conventional audiological evaluation. Descriptive and comparative statistical analyses were performed with a control group of 51 healthy patients., Results: The prevalence of ENT symptoms associated was significantly detected in 88 patients of 130 in Group A (relative frequency (%) 67.6; p=0.041) and in 51 patients of 130 in the control Group B (relative frequency (%) 39.2; p=0.063). In relation to prevalence of SDB, 54 subjects have presented nocturnal respiratory obstructive symptoms from mild to severe (relative frequency (%) 61.3; p=0.033) vs. 20 patients of Group B (relative frequency (%) 39.2; p=0.055). The obstructive severity average type was correlated to the consensual adenotonsillar development (size 3-4), (relative frequency (%) 45.4; p=0.047). The audiological deficits found were mostly of transmissive type with OME correlated and linked to the presence of occasional episodes of AOM. The four PANDAS patients who presented orobuccal dystonia (relative frequency (%) 4.54; p=0.091) achieved an improvement of the algic symptoms through the exercises of self-rehabilitation., Conclusions: Findings from our study show that respiratory diseases, characterizing a group of patients with pandas, are the direct consequences of the malformed or hypertrophic condition and suggesting in these conditions surgical therapy as an approaching tool.

Background: Surfactant protein D (SP-D) is considered a candidate biomarker for lung integrity and for disease progression., Aim: We determined the level of SP-D in children and adolescents with SCD and assessed its possible relation to pulmonary complications and lung function., Methods: Serum SP-D levels were assessed in 50 SCD patients compared with 30 healthy controls. High-resolution computerized tomography (HRCT) of the chest was done. Forced vital capacity (FVC), forced expiratory volume in 1 s (FEV 1 ), FEV 1 /FVC% and forced expiratory flow rate during 25-75% of expiration (FEF25-75%) were determined., Results: SP-D was significantly higher in SCD patients than controls, particularly patients with sickle cell anemia than those with sickle β-thalassemia. SP-D levels were significantly associated with increasing severity of interstitial lung disease. The highest SP-D levels were observed among patients with restrictive lung disease followed by mixed type then obstructive lung disease. SP-D was positively correlated to HbS and serum ferritin while negatively correlated to duration of hydroxyurea treatment and parameters of pulmonary functions. ROC curve analysis revealed that SP-D cutoff value 720 ng/mL could significantly detect the presence of abnormal pulmonary function among SCD patients with 82% sensitivity and 88% specificity. Logistic regression analysis showed that SP-D is an independent factor related to abnormal pulmonary function in SCD., Conclusions: SP-D may be a promising biomarker for screening of SCD patients for risk of later pulmonary complications., (© 2019 Wiley Periodicals, Inc.)

Background: Adverse effects of higher air pollution levels before and after birth on subsequent lung function are often reported in the literature. We assessed whether low-to-moderate levels of air pollution during preschool-age impact upon lung function at school-age., Methods: In a prospective birth cohort of 304 healthy term-born infants, 232 (79%) completed lung function at follow-up at six years. Using spatial-temporal models, levels of individual air pollution (nitrogen dioxide (NO 2 ) and ozone (O 3 ), particulate matter with a diameter <10 μm (PM 10 )) were estimated for the time windows pregnancy, first up to the sixth year of life separately, and birth until follow-up at six years. Time window means were compared to World Health Organization (WHO) guideline limits. Associations of exposure windows with spirometry and body plethysmography indices were analyzed using regression models, adjusting for potential confounders. For subgroup analysis, air pollution exposure was categorized into quartiles (four groups of 52 children)., Results: Mean NO 2 level from birth until follow-up was [mean (range)] [11.8 (4.9 to 35.9 μg/m 3 )], which is almost 4-times lower than the WHO suggested limit of 40 μg/m 3 . In the whole population, increased air pollution levels from birth until follow-up were associated with reduced lung function at six years. In the subgroup analysis, the 52 children exposed to NO 2 levels from the highest quartile during pregnancy, the first and second years of life and from birth until follow-up, had a significant decrease in forced expiratory volume in 1 s (FEV 1 ). Per interquartile range increase of NO 2 , FEV 1 decreased by [z-score change (95% confidence interval)] [-1.07 (-1.67 to -0.47)], [-1.02 (-1.66 to -0.39)], [-0.51 (-0.86 to -0.17)] and [-0.80 (-1.33 to -0.27)], respectively. Air pollution exposure during pregnancy and childhood resulted in a non-significant decrease in lung volume at six years, as assessed by functional residual capacity measured by body plethysmography (FRC pleth )., Conclusion: Our results suggest that exposure to higher NO 2 levels, which are still much lower than WHO guideline limits, especially during the sensitive period of early lung development, may be associated with reduced lung function at school-age. These findings support the concept of age and dose-dependent pollution effects on lung function in healthy school-aged children and underline the importance of pollution reduction measures., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Background: In children with cystic fibrosis (CF) lung clearance index (LCI) from multiple-breath washout (MBW) correlates with structural lung disease. As a shorter test, single-breath washout (SBW) represents an attractive alternative to assess the ventilation distribution, however, data for the correlation with lung imaging are lacking., Methods: We assessed correlations between phase III slope (SIII) of double-tracer gas SBW, nitrogen MBW indices (LCI and moment ratios for overall ventilation distribution, Scond, and Sacin for conductive and mainly acinar ventilation, respectively) and structural lung disease assessed by chest computed tomography (CT) in children with CF., Results: In a prospective cross-sectional study data from MBW, SBW, and chest CT were obtained in 32 children with CF with a median (range) age of 8.2 (5.2-16.3) years. Bronchiectasis was present in 24 (75%) children and air trapping was present in 29 (91%). Median (IQR) SIII of SBW was -138.4 (150.6) mg/mol. We found no association between SIII with either the MBW outcomes or CT scores (n = 23, association with bronchiectasis extent r = 0.10, P = 0.64). LCI and Scond were associated with bronchiectasis extent (n = 23, r = 0.57, P = 0.004; r = 0.60, P = 0.003, respectively)., Conclusions: Acinar ventilation inhomogeneity measured by SBW was not associated with structural lung disease on CT. Double-tracer SBW added no benefit to indices measured by MBW., (© 2019 Wiley Periodicals, Inc.)

Background: The clinical characteristics, hemodynamic changes and outcomes of lung disease-associated pulmonary hypertension (LD-PH) are poorly defined., Methods: A prospective cohort of PH patients undergoing initial hemodynamic assessment was collected, from which 51 patients with LD-PH were identified. Baseline characteristics and long-term survival were compared with 83 patients with idiopathic pulmonary arterial hypertension (iPAH)., Results: Mean age (±standard deviation) of LD-PH patients was 64 ± 10 years, 30% were female and 78% were New York Heart Association class III-IV. The LD-PH group was older than the iPAH group (64 ± 10 vs 56 ± 18 years, respectively, P = 0.003) with a lower percentage of women (30% vs 70%, P = 0.007). LD-PH patients had smaller right ventricular sizes (P = 0.02) and less tricuspid regurgitation (P = 0.03) by echocardiogram, and lower mean pulmonary arterial pressures (mPAP) (P = 0.01) and pulmonary vascular resistance (PVR) (P = 0.001) at catheterization. Despite these findings, mortality was equally high in both groups (P = 0.16). 5-year survival was lower in patients with interstitial lung disease compared to those with obstructive pulmonary disease (P = 0.05). Among the LD-PH population, those with mild to moderately elevated mPAP and those with PVR <7 Wood units demonstrated significantly improved survival (P = 0.04 and P = 0.001, respectively). Vasoreactivity was not associated with improved survival (P = 0.64). A PVR ≥7 Wood units was associated with increased risk of mortality (hazard ratio (95% confidence interval), 3.59 (1.27-10.19), P = 0.02)., Conclusions: Despite less severe PH and less right heart sequelae, LD-PH has an equally poor clinical outcome when compared to iPAH. A PVR ≥7 Wood units in LD-PH patients was associated with 3-fold higher mortality., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

This review presents an analysis of the literature on the topic of respiratory muscle (RM) dysfunction in various forms of respiratory pathology: chronic obstructive pulmonary disease (COPD), asthma, community-acquired pneumonia, idiopathic pulmonary fibrosis (IPF), sarcoidosis and interstitial lung diseases (ILD), associated with systemic connective tissue diseases (polymyositis, dermatomyositis and systemic lupus erythematosus - SLE). Various clinical and pathophysiological aspects of RM dysfunction and general patterns of its pathogenesis were examined. It was proved that the role of RM in the development of respiratory failure depends on the form and stage of the pulmonary pathology and the severity of systemic manifestations of these diseases: excessive proteolysis, oxidative stress, hypoxia, chronic systemic inflammation. These factors modify the morphofunctional status of RM, worsens their contractile function, which is contributed to the development of respiratory failure. In some cases, the primary weakness of RM precedes the clinical manifestation of pulmonary pathology, which is distinctive for some variants of myositis-associated ILD and SLE. Endogenous intoxication syndrome plays a significant role in the development of RM dysfunction during community-acquired pneumonia. It is noted that sarcoid pulmonary ventilation disorders associate with the RM weakness, but not with the degree of lung damage. In most cases, secondary RM dysfunction predominates that contributes to respiratory failure progression, which is especially noticeable in case of COPD, asthma and IPF.

Background: Sitting time and physical activity may be modifiable determinants of lung function. The purpose of this study was to assess the effect that replacing various movement behaviours has on lung function among individuals with and without obstructive lung disease., Data and Methods: For analysis, data were used from participants of the Canadian Longitudinal Study on Aging, recruited between 2012 and 2015. Lung function was assessed using spirometry. A modified version of the Physical Activity Scale for the Elderly was used to assess sitting time and physical activity levels. Isotemporal substitution analysis was performed to analyze the effects of replacing 30 minutes per day of one movement behaviour with another, keeping the total time constant. Analyses were run separately for individuals with an obstructive lung disease (asthma, chronic obstructive pulmonary disease, or forced expiratory volume in 1 second [FEV₁] ⟨ 5th percentile lower limit of normal; n=3,398), and healthy adults (n=14,707)., Results: When sitting time was replaced with 30 minutes per day of any type of physical activity or sleep, an increase in percent (%) of predicted FEV₁ (i.e., β=0.65, confidence interval [CI]: 0.43, 0.88 for replacing sitting time with strenuous or strengthening activity) was observed among healthy adults. Among adults with obstructive lung disease, replacing 30 minutes per day of sitting time or sleep duration with strenuous or strengthening activity was associated with an improvement in the percent of predicted FEV₁ (i.e., β=0.98, CI: 0.13, 1.82 for replacing sleep duration with strenuous or strengthening activity)., Discussion: Replacing sitting time with physical activity leads to significant improvements in lung function among adults with an obstructive lung disease, as well as among adults without a respiratory disease.

Rationale: CC16 (club cell secretory protein-16), a member of the secretoglobin family, is one of the most abundant proteins in normal airway secretions and has been described as a serum biomarker for obstructive lung diseases., Objectives: To determine whether low CC16 is a marker for airway pathology or is implicated in the pathophysiology of progressive airway damage in these conditions., Methods: Using human data from the birth cohort of the Tucson Children's Respiratory Study, we examined the relation of circulating CC16 levels with pulmonary function and responses to bronchial methacholine challenge from childhood up to age 32 years. In wild-type and CC16 -/- mice, we set out to comprehensively examine pulmonary physiology, inflammation, and remodeling in the naive airway., Measurements and Main Results: We observed that Tucson Children's Respiratory Study participants in the lowest tertile of serum CC16 had significant deficits in their lung function and enhanced airway hyperresponsiveness to methacholine challenge from 11 years throughout young adult life. Similarly, CC16 -/- mice had significant deficits in lung function and enhanced airway hyperresponsiveness to methacholine as compared with wild-type mice, which were independent of inflammation and mucin production. As compared with wild-type mice, CC16 -/- mice had significantly elevated gene expression of procollagen type I, procollagen type III, and α-smooth muscle actin, areas of pronounced collagen deposition and significantly enhanced smooth muscle thickness., Conclusions: Our findings support clinical observations by providing evidence that lack of CC16 in the lung results in dramatically altered pulmonary function and structural alterations consistent with enhanced remodeling.

Rationale: Obstructive lung disease is diagnosed by a decreased ratio of forced expiratory volume in 1 second (FEV 1 ) to forced vital capacity (FVC); however, there is no universally accepted lower limit of normal for the FEV 1 /FVC ratio. Current established reference values use the Third National Health and Nutrition Examination Survey (NHANES III) database. In 2012, the Global Lung Initiative (GLI) introduced GLI12, which is a compilation reference set that uses standard deviation values to define normal spirometry., Objectives: To evaluate the changes in classification of obstructive spirometry with use of GLI12 compared with NHANES III in a heterogeneous, multiracial population., Methods: We evaluated the spirometry studies conducted in our pulmonary function laboratory between January 2005 and December 2015. NHANES III reference equations were calculated to predict lower limits of normal for FEV 1 , FVC, and FEV 1 /FVC. GLI12 values were established using European Respiratory Society published computer software. FEV 1 severity was graded using 2005 American Thoracic Society guidelines for NHANES III and using z-score-based criteria for GLI12. Asymmetric partition analysis evaluated agreement between the reference sets., Results: A total of 11,888 studies were evaluated. Obstruction was diagnosed in 2,857 studies using NHANES III versus 2,489 studies using GLI12. Agreement regarding the presence or absence of obstruction occurred in 2,483 of studies with obstruction and 9,025 studies without obstruction (agreement, 96.8%; κ = 0.91). Of the studies with obstruction, 1,595 had agreement in severity grading. Overall, agreement regarding obstruction and severity grading occurred in 10,620 studies, representing 89.3% of all studies. A total of 380 studies (3.2%) had discordance regarding the presence or absence of obstruction, 34.0% (844 of the 2,483 obstruction studies) had a one-degree of change in FEV 1 disease severity scoring, with 44 cases (1.8%) that had changes of two categories in FEV 1 severity scores. No studies had greater than two degrees of change. Asymmetric partition analysis suggested that the highest clinically significant changes were seen in older individuals, particularly African American men older than 65., Conclusions: Our evaluation suggests that there is moderate overall agreement between NHANES III and GLI12. We found a 3.2% change in classification of obstruction when transitioning from NHANES III to GLI12. When incorporating a z-score-based FEV 1 and GLI12 reference set, 10.7% of the spirometry studies had a change in their categorization. The disagreement between the two datasets was most pronounced in elderly subjects. Although we cannot endorse one reference set over the other, we highlight the potential implications of adopting the GLI12 reference sets and suggest caution when interpreting spirometry in the elderly.

Background: Poor lung function is a predictor of future all-cause mortality. In Australia, respiratory diseases are particularly prevalent among the indigenous population, especially in remote communities. However, there are little published pulmonary function tests' (PFT) data of remote-based adult indigenous patients., Aim: To evaluate the severity of airflow obstruction and other PFT abnormalities of adults referred to specialist respiratory clinics in remote indigenous communities., Methods: Retrospective analysis of PFT (pre- and post-bronchodilator spirometry, total lung capacity (TLC) and diffusing capacity to carbon monoxide (DLCO)) of indigenous patients collected during specialist respiratory clinics in remote Northern Territory (NT) indigenous communities (Australia) between 2013 and 2015. The National Health and Nutrition Examination Survey (NHANES) III without ethnic correction was used as the reference., Results: Of the 357 patients, 150 had acceptable spirometry, and 71 had acceptable DLCO and TLC studies. Despite the relatively young age (mean = 49 years, SD = 12.9), their lung function was generally low; mean % predicted values were FEV 1 = 55% (SD = 20.5%), FVC = 61% (SD = 15.6%), DLCO = 64.0% (SD = 19.7%) and TLC = 70.1% (SD = 18.2%). Mean FEV 1 /FVC ratio was preserved (0.71, SD = 0.16). Post-bronchodilator airflow obstruction (FEV 1 /FVC < 0.7) was observed in 37% of patients, where a large proportion (67%) demonstrated at least a severe airflow obstruction, with a mean FEV 1 of 41% predicted., Conclusion: In this first study of PFT findings of indigenous adults from a remote-based clinical service, we found a high rate of at least moderate airflow limitation and low FVC along with preserved FEV1/FVC ratio. Increased awareness and screening for reduced lung function needs to be considered in this population., (© 2018 Royal Australasian College of Physicians.)

The CODEX index was developed and validated in patients hospitalized for COPD exacerbation to predict the risk of death and readmission within one year after discharge. Our study aimed to validate the CODEX index in a large external population of COPD patients with variable durations of follow-up. Additionally, we aimed to recalculate the thresholds of the CODEX index using the cutoffs of variables previously suggested in the 3CIA study (mCODEX). Individual data on 2,755 patients included in the COPD Cohorts Collaborative International Assessment Plus (3CIA+) were explored. A further two cohorts (ESMI AND EGARPOC-2) were added. To validate the CODEX index, the relationship between mortality and the CODEX index was assessed using cumulative/dynamic ROC curves at different follow-up periods, ranging from 3 months up to 10 years. Calibration was performed using univariate and multivariate Cox proportional hazard models and Hosmer-Lemeshow test. A total of 3,321 (87.8% males) patients were included with a mean ± SD age of 66.9 ± 10.5 years, and a median follow-up of 1,064 days (IQR 25-75% 426-1643), totaling 11,190 person-years. The CODEX index was statistically associated with mortality in the short- (≤3 months), medium- (≤1 year) and long-term (10 years), with an area under the curve of 0.72, 0.70 and 0.76, respectively. The mCODEX index performed better in the medium-term (<1 year) than the original CODEX, and similarly in the long-term. In conclusion, CODEX and mCODEX index are good predictors of mortality in patients with COPD, regardless of disease severity or duration of follow-up.

Introduction: Restrictive spirometry pattern is an under-recognised disorder with a poor morbidity and mortality prognosis. We compared physical activity levels between adults with a restrictive spirometry pattern and with normal spirometry., Methods: Restrictive spirometry pattern was defined as a having post-bronchodilator FEV 1 /FVC ≥ Lower Limit of Normal and a FVC<80% predicted in two population-based studies (ECRHS-III and SAPALDIA3). Physical activity was measured using the International Physical Activity Questionnaire. The odds of having low physical activity (<1st study-specific tertile) was evaluated using adjusted logistic regression models., Results: Subjects with a restrictive spirometry pattern (n = 280/4721 in ECRHS, n = 143/3570 in SAPALDIA) reported lower levels of physical activity than those with normal spirometry (median of 1770 vs 2253 MET·min/week in ECRHS, and 3519 vs 3945 MET·min/week in SAPALDIA). Subjects with a restrictive spirometry pattern were more likely to report low physical activity (meta-analysis odds ratio: 1.41 [95%CI 1.07-1.86]) than those with a normal spirometry. Obesity, respiratory symptoms, co-morbidities and previous physical activity levels did not fully explain this finding., Conclusion: Adults with a restrictive spirometry pattern were more likely to report low levels of physical activity than those with normal spirometry. These results highlight the need to identify and act on this understudied but prevalent condition., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

To investigate predictors of accelerated decline in forced expiratory volume in 1 s (FEV 1 ) in individuals with preexisting airflow limitation (AL). Participants in the Health2006 baseline study aged ≥ 35 with FEV 1 / forced vital capacity (FVC) < lower limit of normal (LLN) were invited for a 10-year follow-up. At both examinations, data were obtained on demographics, spirometry, fitness level, allergy, and exhaled nitric oxide. We used multiple regression modeling to predict the annual decline in FEV 1 , reported as regression coefficients ( R) and 95% confidence intervals (CIs). A total of 123 (43% of those invited) participated in the follow-up examination, where more had exercise-induced dyspnea but fewer had asthma symptoms. Being female ( R = -29.8 ml, CI: -39.7 to -19.8), diagnosed with asthma ( R = -13.7, CI: -20.4 to -7.0) or atopic dermatitis ( R = -29.0, CI: -39.7 to -18.4), and having current asthma symptoms or nightly respiratory symptoms ( R = -22.1, CI: -31.9 to -12.4 and R = -14.3, CI: -19.9 to -8.7, respectively) were significantly associated with a steeper decline in FEV 1 . Although to a smaller extent, a steeper decline was also predicted by age, baseline FEV 1 , waist/hip-ratio, and number of pack-years smoked. In individuals with preexisting AL, being female and having ever or current respiratory symptoms were associated with an accelerated annual decline in FEV 1 .

Background: Electrical impedance tomography is a continuous imaging method capable of measuring lung volume changes. The purpose of this study was to examine whether EIT was capable of evaluating the degree of obstructive ventilatory defect (OVD) on the global and regional level., Methods: 41 healthy subjects with no lung diseases and 67 subjects suffering from obstructive lung diseases were examined using EIT and spirometry during forced vital capacity (FVC) maneuver. The subjects were divided into control group (n = 41), early airway obstruction group (n = 26), mild group (n = 17), moderate group (n = 16) and severe group (n = 8) according to the degree of obstruction. Forced expiratory volume in 1 second (FEV1) and FEV1/FVC were determined by EIT. The mode index (MI) was proposed to evaluate the degree of global and regional obstruction; the effectiveness of MI was validated by evaluating posture related change of lung emptying capacity in sitting and supine postures; the degree of regional obstruction was determined according to the cut-off values of MI obtained from receiver operating characteristic (ROC) analysis; regional obstruction was located in the four-quadrant region of interest (ROI) and the contour-map ROI with contour lines at the cut-off values of MI., Results: Significant differences were found between different groups (P<0.05) and the global MI was 0.93±0.03, 0.86±0.05, 0.81±0.09, 0.73±0.09 and 0.60±0.11 (mean ±SD), respectively. The cut-off MI value was 0.90, 0.83, 0.77, and 0.65, respectively., Conclusion: The results indicated the potential of EIT to evaluate the degree of obstruction in patients with obstructive ventilatory defect on the global and regional level., Competing Interests: The authors have declared that no competing interests exist.

Background: Reduced lung function predicts increased mortality, but its prevalence may vary depending on definition considered, use of bronchodilation and applied reference values. We aimed to assess lung function abnormalities in Lausanne, Switzerland, and their association with clinical history., Methods: In a general population sample, spirometry was performed and bronchodilation applied if the ratio forced expiratory volume in 1 s (FEV1) / forced vital capacity (FVC) or the FVC was below the lower limit of normal (LLN) according to Global Lung Function Initiative 2012 references. Results for FEV1/FVC according to the LLN were compared to the 0.7 fixed ratio. Respiratory risk factors, symptoms and self-reported respiratory diagnoses were recorded through a questionnaire., Results: Out of the 3342 included subjects, 3.8% had chronic obstruction and 2.5% reversible obstruction when using the LLN; possible lung restriction alone was present in 1.8%, and associated with chronic obstruction in 0.4%. Ever smokers had a higher prevalence of abnormal spirometry, chronic obstruction and reversible obstruction; there was no difference with regard to possible restriction. Overall, chronic airway obstruction was found in 8.9% of current smokers, 4.6% of former smokers and 1.5% of never smokers. Only one third of participants with chronic obstruction were aware of a respiratory disease., Conclusion: Prevalence of abnormal lung function in the population of Lausanne is low. This may be due to a low rate of ever-smokers, the application of a full bronchodilation dose, but also to inherent characteristics of this population.