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Csonka L, Tikkakoski A, Tikkakoski AP, Karjalainen J, Lehtimäki L. Relation of changes in PEF and FEV1 in exercise challenge in children. Clin Physiol Funct Imaging 2024; 44:179-185. [PMID: 37933772 DOI: 10.1111/cpf.12864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 09/12/2023] [Accepted: 10/30/2023] [Indexed: 11/08/2023]
Abstract
Decrease in forced expiratory volume in one second (FEV1 ) of 10% or 15% in exercise challenge test is considered diagnostic for asthma, but a decrease of 15% in peak expiratory flow (PEF) is recommended as an alternative. Our aim was to assess the accuracy of different PEF cut-off points in comparison to FEV1 . We retrospectively studied 326 free running exercise challenge tests with spirometry in children 6-16 years old. FEV1 and PEF were measured before and 2, 5, 10 and 15 min after exercise. Receiver operating characteristics (ROC) analysis, sensitivity, specificity, positive and negative predictive values (PPV and NPV) and ϰ-coefficient were used to analyse how decrease in PEF predicts decrease of 10% or 15% in FEV1 . In the ROC analysis, areas under the curve were 0.851 (p < 0.001) and 0.921 (p < 0.001) for PEF decrease to predict a 10% and 15% decrease in FEV1 , respectively. The agreement between changes in PEF and FEV1 varied from slight to substantial (ϰ values of 0.199-0.680) depending on the cut-points. Lower cut-off for decrease in PEF had higher sensitivity and NPV, while higher cut-off values had better specificity and PPV. Decrease of 20% and 25% in PEF seemed to be the best cut-offs for detecting 10% and 15% decrease in FEV1 , respectively. Still, a fifth of the positive findings based on PEF were false. Change in PEF is not a precise predictor of change in FEV1 in exercise test. The currently recommended cut-point of 15% decrease in PEF seems to be too low and leads to high false positive rate.
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Affiliation(s)
- Leon Csonka
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Antti Tikkakoski
- Department of Clinical Physiology and Nuclear Medicine, Tampere University Hospital, Tampere, Finland
| | - Anna P Tikkakoski
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Jussi Karjalainen
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
- Allergy Centre, Tampere University Hospital, Tampere, Finland
| | - Lauri Lehtimäki
- Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
- Allergy Centre, Tampere University Hospital, Tampere, Finland
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Agache I, Antolin‐Amerigo D, Blay F, Boccabella C, Caruso C, Chanez P, Couto M, Covar R, Doan S, Fauquert J, Gauvreau G, Gherasim A, Klimek L, Lemiere C, Nair P, Ojanguren I, Peden D, Perez‐de‐Llano L, Pfaar O, Rondon C, Rukhazde M, Sastre J, Schulze J, Silva D, Tarlo S, Toppila‐Salmi S, Walusiak‐Skorupa J, Zielen S, Eguiluz‐Gracia I. EAACI position paper on the clinical use of the bronchial allergen challenge: Unmet needs and research priorities. Allergy 2022; 77:1667-1684. [PMID: 34978085 DOI: 10.1111/all.15203] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Revised: 12/16/2021] [Accepted: 12/27/2021] [Indexed: 12/22/2022]
Abstract
Allergic asthma (AA) is a common asthma phenotype, and its diagnosis requires both the demonstration of IgE-sensitization to aeroallergens and the causative role of this sensitization as a major driver of asthma symptoms. Therefore, a bronchial allergen challenge (BAC) would be occasionally required to identify AA patients among atopic asthmatics. Nevertheless, BAC is usually considered a research tool only, with existing protocols being tailored to mild asthmatics and research needs (eg long washout period for inhaled corticosteroids). Consequently, existing BAC protocols are not designed to be performed in moderate-to-severe asthmatics or in clinical practice. The correct diagnosis of AA might help select patients for immunomodulatory therapies. Allergen sublingual immunotherapy is now registered and recommended for controlled or partially controlled patients with house dust mite-driven AA and with FEV1 ≥ 70%. Allergen avoidance is costly and difficult to implement for the management of AA, so the proper selection of patients is also beneficial. In this position paper, the EAACI Task Force proposes a methodology for clinical BAC that would need to be validated in future studies. The clinical implementation of BAC could ultimately translate into a better phenotyping of asthmatics in real life, and into a more accurate selection of patients for long-term and costly management pathways.
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Affiliation(s)
- Ioana Agache
- Faculty of Medicine Transylvania University Brasov Romania
| | - Dario Antolin‐Amerigo
- Servicio de Alergia Hospital Universitario Ramón y Cajal Instituto Ramón y Cajal de Investigación Sanitaria Madrid Spain
| | - Frederic Blay
- ALYATEC Environmental Exposure Chamber Chest Diseases Department Strasbourg University Hospital University of Strasbourg Strasbourg France
| | - Cristina Boccabella
- Department of Cardiovascular and Thoracic Sciences Università Cattolica del Sacro Cuore Fondazione Policlinico Universitario A. Gemelli ‐ IRCCS Rome Italy
| | | | - Pascal Chanez
- Department of Respiratory CIC Nord INSERMINRAE C2VN Aix Marseille University Marseille France
| | - Mariana Couto
- Centro de Alergia Hospital CUF Descobertas Lisboa Portugal
| | - Ronina Covar
- Pediatrics National Jewish Health Denver Colorado USA
| | | | | | - Gail Gauvreau
- Division of Respirology Department of Medicine McMaster University Hamilton Ontario Canada
| | - Alina Gherasim
- ALYATEC Environmental Exposure Chamber Strasbourg France
| | - Ludger Klimek
- Center for Rhinology and Allergology Wiesbaden Germany
| | - Catherine Lemiere
- Research Centre Centre Intégré Universitaire de santé et de services sociaux du Nord‐de‐l'île‐de‐Montréal Montréal Quebec Canada
- Faculty of Medicine Université de Montreal Montreal Quebec Canada
| | - Parameswaran Nair
- Department of Medicine Firestone Institute of Respiratory Health at St. Joseph's Healthcare McMaster University Hamilton Ontario Canada
| | - Iñigo Ojanguren
- Departament de Medicina Servei de Pneumología Hospital Universitari Valld´Hebron Universitat Autònoma de Barcelona (UAB) Institut de Recerca (VHIR) CIBER de Enfermedades Respiratorias (CIBERES) Barcelona Spain
| | - David Peden
- Division of Pediatric Allergy and Immunology Center for Environmental Medicine, Asthma and Lung Biology The School of Medicine The University of North Carolina at Chapel Hill Chapel Hill North Carolina USA
| | - Luis Perez‐de‐Llano
- Department of Respiratory Medicine University Hospital Lucus Augusti Lugo Spain
| | - Oliver Pfaar
- Section of Rhinology and Allergy Department of Otorhinolaryngology, Head and Neck Surgery University Hospital Marburg Philipps‐Universität Marburg Marburg Germany
| | - Carmen Rondon
- Allergy Unit Hospital Regional Universitario de Malaga Instituto de Investigacion Biomedica de Malaga (IBIMA) Malaga Spain
| | - Maia Rukhazde
- Center of Allergy & Immunology Teaching University Geomedi LLC Tbilisi Georgia
| | - Joaquin Sastre
- Allergy Unit Hospital Universitario Fundación Jiménez Díaz Center for Biomedical Network of Respiratory Diseases (CIBERES) Instituto de Salud Carlos III (ISCIII) Madrid Spain
| | - Johannes Schulze
- Department for Children and Adolescents, Division of Allergology Pulmonology and Cystic Fibrosis Goethe‐University Hospital Frankfurt am Main Germany
| | - Diana Silva
- Basic and Clinical Immunology Unit Department of Pathology Faculty of Medicine University of Porto and Serviço de Imunoalergologia Centro Hospitalar São João, EPE Porto Portugal
| | - Susan Tarlo
- Respiratory Division Department of Medicine University Health Network, Toronto Western Hospital University of Toronto Department of Medicine, and Dalla Lana Department of Public Health Toronto Ontario Canada
| | - Sanna Toppila‐Salmi
- Haartman Institute, Medicum, Skin and Allergy Hospital Hospital District of Helsinki and Uusimaa Helsinki University Hospital and University of Helsinki Helsinki Finland
| | - Jolanta Walusiak‐Skorupa
- Department of Occupational Diseases and Environmental Health Nofer Institute of Occupational Medicine Łódź Poland
| | - Stefan Zielen
- Department for Children and Adolescents, Division of Allergology Pulmonology and Cystic Fibrosis Goethe‐University Hospital Frankfurt am Main Germany
| | - Ibon Eguiluz‐Gracia
- Allergy Unit Hospital Regional Universitario de Malaga Instituto de Investigacion Biomedica de Malaga (IBIMA) Malaga Spain
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McMahon L, Blake C, Lennon O. Nonpharmacological interventions for respiratory health in Parkinson's disease: A systematic review and meta-analysis. Eur J Neurol 2020; 28:1022-1040. [PMID: 33098349 DOI: 10.1111/ene.14605] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 10/15/2020] [Indexed: 12/29/2022]
Abstract
BACKGROUND AND PURPOSE Respiratory dysfunction in Parkinson's disease (PD) is often an underdiagnosed and untreated impairment associated with the disease. Clinically, a reactive approach to respiratory morbidity is taken, rather than preventative approaches that address underlying impairment/s. This systematic review identifies the current evidence to support nonpharmacological interventions to improve respiratory impairments in individuals with PD. METHODS The relevant literature was searched using a customised and systematic strategy. Randomised and nonrandomised control trials of nonpharmacological interventions targeting respiratory outcome measures in PD were included. Outcomes of interest were respiratory morbidity and mortality, respiratory muscle strength, spirometry measures, lung volumes, peak cough flow, and perception of dyspnoea. RESULTS Nonpharmacological interventions included: functional training, generalised strength training, respiratory muscle strength training, aerobic exercise, qigong, yoga, breath stacking, incentive spirometry and singing. Methodological quality of included studies varied. Meta-analyses of nonpharmacological interventions demonstrated significant effects for inspiratory muscle strength (mean difference [MD] 19.68; confidence interval [CI] 8.49, 30.87; z = 3.45; p = 0.0006; I2 = 2%), expiratory muscle strength (MD 18.97; CI 7.79, 30.14; z = 3.33; p = 0.0009; I2 = 23%) and peak expiratory flow (MD 72.21; CI 31.19, 113.24; z = 3.45; p = 0.0006; I2 = 0%). Best-evidence synthesis identified level 1 evidence supporting nonpharmacological interventions for improving peak cough flow and perceived dyspnoea. No studies were identified reporting outcomes of respiratory rate, inspiration:expiration ratio or respiratory morbidity or mortality in PD. CONCLUSIONS Nonpharmacological interventions improved respiratory muscle strength and peak expiratory flow in PD. Additional trials targeting respiratory dysfunction and longitudinal studies examining the relationship between respiratory dysfunction and morbidity and mortality rates in PD are required.
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Affiliation(s)
- L McMahon
- UCD School of Public Health, Physiotherapy and Population Science, Health Sciences Centre, University College Dublin, Dublin, Ireland
| | - C Blake
- UCD School of Public Health, Physiotherapy and Population Science, Health Sciences Centre, University College Dublin, Dublin, Ireland
| | - O Lennon
- UCD School of Public Health, Physiotherapy and Population Science, Health Sciences Centre, University College Dublin, Dublin, Ireland
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Nelson J, Chalbot MCG, Pavicevic Z, Kavouras IG. Characterization of exhaled breath condensate (EBC) non-exchangeable hydrogen functional types and lung function of wildland firefighters. J Breath Res 2020; 14:046010. [PMID: 32969351 DOI: 10.1088/1752-7163/abb761] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Inhalation of smoke is shown to be associated with adverse respiratory outcomes in firefighters. Due to invasiveness of procedures to obtain airways lining fluid, the immediate responses of the target organ (i.e. lung) are secondarily assessed through biomarkers in blood and urine. The objective of this study was to identify changes in metabolic profile of exhaled breath condensate (EBC) and lung function of firefighters exposed to wildfires smoke. A total of 29 subjects were studied over 16 events; 14 of these subjects provided cross-shift EBC samples. The predominant types of non-exchangeable hydrogen in EBC were saturated oxygenated hydrogen, aliphatic alkyl and allylic. Non-exchangeable allylic and oxygenated hydrogen concentrations decreased in post-exposure EBC samples. Longer exposures were correlated with increased abundance of oxidized carbon in ketones, acids and esters. Post-exposure lung function declines (forced expiratory volume in 1 s (FEV1): 0.08 l, forced vital capacity (FVC): 0.07 l, FEV1/FVC: 0.03 l, peak expiratory flow (PEF): 0.39 l s-1) indicated airways inflammation. They were related to exposure intensity (FEV1 and FVC) and exposure duration (PEF). This study showed that EBC characterization of non-exchangeable hydrogen types by NMR may provide insights on EBC molecular compositions in response to smoke inhalation and facilitate targeted analysis to identify specific biomarkers.
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Affiliation(s)
- Jordan Nelson
- Department of Environmental Health Sciences, Ryals School of Public Health, University of Alabama at Birmingham, Birmingham, AL 35219, United States of America
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Ng CFS, Hashizume M, Obase Y, Doi M, Tamura K, Tomari S, Kawano T, Fukushima C, Matsuse H, Chung Y, Kim Y, Kunimitsu K, Kohno S, Mukae H. Associations of chemical composition and sources of PM 2.5 with lung function of severe asthmatic adults in a low air pollution environment of urban Nagasaki, Japan. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 252:599-606. [PMID: 31185348 DOI: 10.1016/j.envpol.2019.05.117] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 05/22/2019] [Accepted: 05/22/2019] [Indexed: 05/17/2023]
Abstract
Previous studies have linked ambient PM2.5 to decreased pulmonary function, but the influence of specific chemical elements and emission sources on the severe asthmatic is not well understood. We examined the mass, chemical constituents, and sources of PM2.5 for short-term associations with the pulmonary function of adults with severe asthma in a low air pollution environment in urban Nagasaki, Japan. We recruited 35 asthmatic adults and obtained the daily record of morning peak expiratory flow (PEF) in spring 2014-2016. PM2.5 filters were extracted from an air quality monitoring station (178 days) and measured for 27 chemical elements. Source apportionment was performed using Positive Matrix Factorization (PMF). We fitted generalized linear model with generalized estimating equation (GEE) method to estimate changes in PEF (from personal monthly maximum) and odds of severe respiratory deterioration (first ≥ 15% PEF reduction within a 1-week interval) associated with mass, constituents, and sources of PM2.5, with adjustment for temperature and relative humidity. Constituent sulfate (SO42-) and PM2.5 from oil combustion and traffic were associated with reduced PEF. An interquartile range (IQR) increase in SO42- (3.7 μg/m3, average lags 0-1) was associated with a decrease of 0.38% (95% confidence interval = -0.75% to -0.001%). An IQR increase in oil combustion and traffic-sourced PM2.5 (2.64 μg/m3, lag 1) was associated with a decrease of 0.33% (-0.62% to -0.002%). We found a larger PEF decrease associated with PM2.5 from dust/soil on Asian Dust days. There was no evidence linking total mass and metals to reduced pulmonary function. The ventilatory capacity of adults with severe asthma is susceptible to specific constituents/sources of PM2.5 such as sulfate and oil combustion and traffic despite active self-management of asthma and low air pollution levels in the study location.
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Affiliation(s)
- Chris Fook Sheng Ng
- School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki, Japan; Department of Public Health, Environment and Society, London School of Hygiene & Tropical Medicine, London, United Kingdom; Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Masahiro Hashizume
- School of Tropical Medicine and Global Health, Nagasaki University, Nagasaki, Japan; Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Yasushi Obase
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan.
| | - Masataka Doi
- Nagasaki Prefectural Institute of Environment and Public Health, Omura, Nagasaki, Japan
| | - Kei Tamura
- Environmental Policy Division, Nagasaki Prefectural Government, Nagasaki, Japan
| | - Shinya Tomari
- Department of Respiratory Medicine, Isahaya General Hospital, Japan Community Health Care Organization (JCHO), Isahaya, Nagasaki, Japan
| | - Tetsuya Kawano
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Chizu Fukushima
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Hiroto Matsuse
- Department of Internal Medicine, Division of Respiratory Medicine, Toho University Ohashi Medical Center, Tokyo, Japan
| | - Yeonseung Chung
- Department of Mathematical Sciences, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Yoonhee Kim
- Department of Global Environmental Health, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Kenichi Kunimitsu
- Nagasaki Prefectural Institute of Environment and Public Health, Omura, Nagasaki, Japan
| | - Shigeru Kohno
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Hiroshi Mukae
- Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
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Rohr AC. Ozone exposure and pulmonary effects in panel and human clinical studies: Considerations for design and interpretation. JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION (1995) 2018; 68:288-307. [PMID: 29315024 DOI: 10.1080/10962247.2018.1424056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Accepted: 12/22/2017] [Indexed: 06/07/2023]
Abstract
UNLABELLED A wealth of literature exists regarding the pulmonary effects of ozone, a photochemical pollutant produced by the reaction of nitrogen oxide and volatile organic precursors in the presence of sunlight. This paper focuses on epidemiological panel studies and human clinical studies of ozone exposure, and discusses issues specific to this pollutant that may influence study design and interpretation as well as other, broader considerations relevant to ozone-health research. The issues are discussed using examples drawn from the wider literature. The recent panel and clinical literature is also reviewed. Health outcomes considered include lung function, symptoms, and pulmonary inflammation. Issues discussed include adversity, reversibility, adaptation, variability in ozone exposure metric used and health outcomes evaluated, co-pollutants in panel studies, influence of temperature in panel studies, and multiple comparisons. Improvements in and standardization of panel study approaches are recommended to facilitate comparisons between studies as well as meta-analyses. Additional clinical studies at or near the current National Ambient Air Quality Standard (NAAQS) of 70 ppb are recommended, as are clinical studies in sensitive subpopulations such as asthmatics. IMPLICATIONS The pulmonary health impacts of ozone exposure have been well documented using both epidemiological and chamber study designs. However, there are a number of specific methodological and related issues that should be considered when interpreting the results of these studies and planning additional research, including the standardization of exposure and health metrics to facilitate comparisons among studies.
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Wu S, Deng F, Hao Y, Wang X, Zheng C, Lv H, Lu X, Wei H, Huang J, Qin Y, Shima M, Guo X. Fine particulate matter, temperature, and lung function in healthy adults: findings from the HVNR study. CHEMOSPHERE 2014; 108:168-174. [PMID: 24548647 DOI: 10.1016/j.chemosphere.2014.01.032] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Revised: 12/06/2013] [Accepted: 01/05/2014] [Indexed: 06/03/2023]
Abstract
Both ambient particulate air pollution and temperature alterations have been associated with adverse human health effects, but the interactive effect of ambient particulate and temperature on human health remains uncertain. The present study investigated the effects of ambient particulate matter with an aerodynamic diameter⩽2.5 μm (PM2.5) and temperature on human lung function simultaneously in a panel of 21 healthy university students from the Healthy Volunteer Natural Relocation (HVNR) study in the context of suburban/urban air pollution in Beijing, China. Each study subject used an electronic diary meter to record peak expiratory flow (PEF) and forced expiratory volume in 1s (FEV1) twice a day for 6 months in three periods before and after relocating from a suburban area to an urban area with changing ambient PM2.5 and temperature levels in Beijing. Hourly-averaged environmental data were obtained from central air-monitoring sites. Exposure effects were estimated using generalized linear mixed models controlling for potential confounders. Study subjects provided 6494 daily measurements on PEF and 6460 daily measurements on FEV1 over the study. PM2.5 was associated with reductions in evening PEF and morning/evening FEV1 whereas temperature was associated with reductions in morning PEF. The estimated PM2.5 effects on evening PEF and morning/evening FEV1 in the presence of high temperature were generally stronger than those in the presence of low temperature, and the estimated temperature effects on morning/evening PEF and morning FEV1 in the presence of high PM2.5 were also generally stronger than those in the presence of low PM2.5. For example, there were a 2.47% (95% confidence interval: -4.24, -0.69) reduction and a 0.78% (95% confidence interval: -1.59, 0.03) reduction in evening PEF associated with an interquartile range increase (78.7 μg/m(3)) in PM2.5 at 4-d moving average in the presence of high temperature (⩾21.6 °C) and low temperature (<21.6 °C), respectively. Our findings suggest that ambient particulate and temperature may interact synergistically to cause adverse respiratory health effects.
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Affiliation(s)
- Shaowei Wu
- Department of Occupational and Environmental Health Sciences, Peking University School of Public Health, Beijing, China
| | - Furong Deng
- Department of Occupational and Environmental Health Sciences, Peking University School of Public Health, Beijing, China
| | - Yu Hao
- Department of Occupational and Environmental Health Sciences, Peking University School of Public Health, Beijing, China
| | - Xin Wang
- Department of Occupational and Environmental Health Sciences, Peking University School of Public Health, Beijing, China
| | - Chanjuan Zheng
- Department of Occupational and Environmental Health Sciences, Peking University School of Public Health, Beijing, China
| | - Haibo Lv
- Department of Occupational and Environmental Health Sciences, Peking University School of Public Health, Beijing, China
| | - Xiuling Lu
- Department of Occupational and Environmental Health Sciences, Peking University School of Public Health, Beijing, China
| | - Hongying Wei
- Department of Occupational and Environmental Health Sciences, Peking University School of Public Health, Beijing, China
| | - Jing Huang
- Department of Occupational and Environmental Health Sciences, Peking University School of Public Health, Beijing, China
| | - Yu Qin
- Department of Occupational and Environmental Health Sciences, Peking University School of Public Health, Beijing, China
| | - Masayuki Shima
- Department of Public Health, Hyogo College of Medicine, Hyogo, Japan
| | - Xinbiao Guo
- Department of Occupational and Environmental Health Sciences, Peking University School of Public Health, Beijing, China.
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Wu S, Deng F, Hao Y, Shima M, Wang X, Zheng C, Wei H, Lv H, Lu X, Huang J, Qin Y, Guo X. Chemical constituents of fine particulate air pollution and pulmonary function in healthy adults: the Healthy Volunteer Natural Relocation study. JOURNAL OF HAZARDOUS MATERIALS 2013; 260:183-191. [PMID: 23747477 DOI: 10.1016/j.jhazmat.2013.05.018] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Revised: 04/26/2013] [Accepted: 05/11/2013] [Indexed: 06/02/2023]
Abstract
The study examined the associations of 32 chemical constituents of particulate matter with an aerodynamic diameter ≤2.5 μm (PM₂.₅) with pulmonary function in a panel of 21 college students. Study subjects relocated from a suburban area to an urban area with changing ambient air pollution levels and contents in Beijing, China, and provided daily morning/evening peak expiratory flow (PEF) and forced expiratory volume in 1s (FEV₂₁) measurements over 6 months in three study periods. There were significant reductions in evening PEF and morning/evening FEV₂₁ associated with various air pollutants and PM₂.₅ constituents. Four PM₂.₅ constituents (copper, cadmium, arsenic and stannum) were found to be most consistently associated with the reductions in these pulmonary function measures. These findings provide clues for the respiratory effects of specific particulate chemical constituents in the context of urban air pollution.
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Affiliation(s)
- Shaowei Wu
- Department of Occupational and Environmental Health Sciences, Peking University School of Public Health, Beijing, China
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9
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Diagnosis and prevention of diseases induced by isocyanate. Environ Health Prev Med 2012; 7:40-6. [PMID: 21432263 DOI: 10.1007/bf02897329] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2001] [Accepted: 01/16/2002] [Indexed: 10/22/2022] Open
Abstract
Isocyanates are among the most frequent causes of occupational asthma in industrialized countries. Early diagnosis of diisocyanate asthma followed by prompt termination of chemical exposure can prevent chronic morbidity due to persistent asthma. Chronic exposure to isocyanates also induces hypersensitivity pneumonitis (HP). The accurate diagnosis of diisocynate asthma requires a systematic approach that combines information obtained from the occupational history, immunologic tests and physiologic studies. The prevention of health problems from toluene diisocyanate (TDI), 4,4'-methylenediphenyl diisocyanate (MDI) and 1,6'-hexamethylene diisocyanate (HDI) is essential for all those handling the chemicals. Regulatory exposure limits should be observed. However, wheezing, coughing or even asthmatic attacks may occur after exposure much below the regulatory exposure limits especially in sensitive individuals. Preventing or minimizing exposure is of prime importance and should be supported by the installation of engineering controls, by education of the workforce, by regular monitoring of the workplace exposure and by medical surveillance. To prevent such asthma it is suggested that workers should be tested airway sensitivity and should avoid working in areas that have dust containing specific-IgE. Such tests must be periodically performed after working. Symptoms induced by isocyanate need earlier discover and early isolation of the associated individuals.
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Moore VC, Parsons NR, Jaakkola MS, Burge CBSG, Pantin CF, Robertson AS, Burge PS. Serial lung function variability using four portable logging meters. J Asthma 2009; 46:961-6. [PMID: 19905927 DOI: 10.3109/02770900903229677] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE Portable lung function logging meters that allow measurement of peak expiratory flow (PEF) and forced expiratory volume in 1 second (FEV(1)) are useful for the diagnosis and exclusion of asthma. The aim of this study was to investigate the within and between-session variability of PEF and FEV(1) for four logging meters and to determine the sensitivity of meters to detect FEV(1) and PEF diurnal changes. METHODS Thirteen assessors (all hospital staff members) were asked to record 1 week of 2-hour PEF and FEV(1) measurements using four portable lung function meters. Within-session variability of PEF and FEV(1) were compared for each meter using a coefficient of variation (COV). Between-session variability was quantified using parameter estimates from a cosinor analysis which modeled diurnal change for both lung function measures and also allowed for variation between days for individual sessions. RESULTS The mean within-session COV for FEV(1) was consistently lower than that for PEF (p < 0.001). PEF showed a higher but not significantly different (p = 0.068) sensitivity for detecting diurnal variation than FEV(1). PEF was also slightly more variable between days, but not significantly different than FEV(1) (p = 0.409). PEF and FEV(1) diurnal variability did not differ between the 4 meters (p = 0.154 and 0.882 respectively), but within-session FEV(1) COV differed between meters (p = 0.009). CONCLUSION PEF was marginally more sensitive to within-day variability than FEV(1) but was less repeatable. Overall, differences between the 4 meters were small, suggesting that all meters are clinically useful.
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Affiliation(s)
- Vicky C Moore
- Occupational Lung Disease Unit, Department of Respiratory Medicine, Birmingham Heartlands Hospital, Bordesley Green East, Birmingham B9 5SS, UK.
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Delfino RJ, Staimer N, Tjoa T, Gillen D, Kleinman MT, Sioutas C, Cooper D. Personal and ambient air pollution exposures and lung function decrements in children with asthma. ENVIRONMENTAL HEALTH PERSPECTIVES 2008; 116:550-8. [PMID: 18414642 PMCID: PMC2291010 DOI: 10.1289/ehp.10911] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2007] [Accepted: 11/21/2007] [Indexed: 05/15/2023]
Abstract
BACKGROUND Epidemiologic studies have shown associations between asthma outcomes and outdoor air pollutants such as nitrogen dioxide and particulate matter mass < 2.5 microm in diameter (PM(2.5)). Independent effects of specific pollutants have been difficult to detect because most studies have relied on highly correlated central-site measurements. OBJECTIVES This study was designed to evaluate the relationship of daily changes in percent-predicted forced expiratory volume in 1 sec (FEV(1)) with personal and ambient air pollutant exposures. METHODS For 10 days each, we followed 53 subjects with asthma who were 9-18 years of age and living in the Los Angeles, California, air basin. Subjects self-administered home spirometry in themorning, afternoon, and evening. We measured personal hourly PM(2.5) mass, 24-hr PM(2.5) elemental and organic carbon (EC-OC), and 24-hr NO(2), and the same 24-hr average outdoor central-site(ambient) exposures. We analyzed data with transitional mixed models controlling for personal temperature and humidity, and as-needed beta(2)-agonist inhaler use. RESULTS FEV(1) decrements were significantly associated with increasing hourly peak and daily average personal PM(2.5), but not ambient PM(2.5). Personal NO(2) was also inversely associated with FEV(1). Ambient NO(2) was more weakly associated. We found stronger associations among 37 subjects not taking controller bronchodilators as follows: Personal EC-OC was inversely associated with morning FEV(1); for an interquartile increase of 71 microg/m(3) 1-hr maximum personal PM(2.5), overall percent-predicted FEV(1) decreased by 1.32% [95% confidence interval (CI), -2.00 to -0.65%]; and for an interquartile increase of 16.8 ppb 2-day average personal NO(2), overall percent-predicted FEV(1) decreased by 2.45% (95% CI, -3.57 to -1.33%). Associations of both personal PM(2.5) and NO(2) with FEV(1) remained when co-regressed, and both confounded ambient NO(2). CONCLUSIONS Independent pollutant associations with lung function might be missed using ambient data alone. Different sets of causal components are suggested by independence of FEV(1) associations with personal PM(2.5) mass from associations with personal NO(2).
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Affiliation(s)
- Ralph J Delfino
- Department of Epidemiology, School of Medicine, University of California, Irvine, Irvine, California 92617-7555, USA.
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Arnold DH, Gebretsadik T, Minton PA, Higgins S, Hartert TV. Clinical measures associated with FEV1 in persons with asthma requiring hospital admission. Am J Emerg Med 2007; 25:425-9. [PMID: 17499661 DOI: 10.1016/j.ajem.2006.09.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2006] [Revised: 08/30/2006] [Accepted: 09/05/2006] [Indexed: 10/23/2022] Open
Abstract
OBJECTIVE We sought to determine the association of select clinical measures of asthma severity with percent predicted forced expiratory volume in one-second (%FEV1). METHODS We studied a prospective cohort of adult subjects (N = 129) with asthma exacerbations requiring hospital admission. Clinical data was acquired, including medical and social history, symptoms, vital signs, physical assessment, and spirometry. Predictor variables for this study included manually determined pulsus paradoxus (PP), percent predicted peak expiratory flow rate (%PEFR) and accessory muscle use. The outcome measure was %FEV1. Multiple linear regression analyses were performed to determine the independent associations between predictor variables and %FEV1. RESULTS In univariate analysis, %PEFR correlated with %FEV1 (rho = 0.77, P < .001) and PP correlated negatively with %FEV1 (rho = - 0.384, P < .001). %FEV1 was significantly lower in participants with accessory muscle use (Median %FEV1 = 37.5%, IQR: 27.0-49.0) than in those without accessory muscle use (Median %FEV1= 55.0%, IQR: 39.0-69.0), (P = .004). In multivariable analysis including the covariates %PEFR, accessory muscle use, PP, age, sex, heart rate and respiratory rate, %PEFR (P < .0001) and accessory muscle use (P = .003) remained significantly associated with %FEV1, whereas PP did not (P = .52).
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Affiliation(s)
- Donald H Arnold
- Department of Emergency Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, USA.
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Feldman JM, McQuaid EL, Klein RB, Kopel SJ, Nassau JH, Mitchell DK, Wamboldt MZ, Fritz GK. Symptom perception and functional morbidity across a 1-year follow-up in pediatric asthma. Pediatr Pulmonol 2007; 42:339-47. [PMID: 17358038 PMCID: PMC2966282 DOI: 10.1002/ppul.20584] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The purpose of this study was to examine the association between asthma symptom perception measured during a 5-6 week baseline and functional morbidity measured prospectively across a 1-year follow-up. Symptom perception was measured by comparing subjective ratings with peak expiratory flow rate (PEFR) and forced expiratory volume in one second (FEV(1)). We hypothesized that accurate symptom perception (ASP) would be associated with less functional morbidity. Participants consisted of 198 children with asthma ages 7-17 recruited from three sites. The children used a programmable electronic spirometer in the home setting to guess their PEFR prior to exhalation. Each "subjective" guess was classified as being in an ASP, dangerous symptom perception (DSP; underestimation of symptoms), or symptom magnification (SM; overestimation) zone based upon the corresponding measurement of PEFR or FEV(1). An index of functional morbidity was collected by parent report at baseline and across 1-year follow-up. A greater proportion of ASP blows and a lower proportion of DSP blows based on PEFR predicted less functional morbidity reported at baseline, independent of asthma severity and race/ethnicity. A greater proportion of ASP blows (using PEFR and FEV(1)) and a lower proportion of SM blows (using FEV(1)) predicted less functional morbidity across 1-year follow-up. Symptom perception was not associated with emergency department visits for asthma at baseline or across follow-up. In comparison to PEFR, FEV(1) more frequently detected a decline in pulmonary function that children did not report. Symptom perception measured in naturalistic settings was associated with functional morbidity at baseline and prospectively across 1-year follow-up. Support was found for including multiple measures of pulmonary function in the assessment of asthma symptom perception.
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Affiliation(s)
- Jonathan M Feldman
- Ferkauf Graduate School of Psychology, Yeshiva University, Bronx, New York 10461, USA.
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Drobnic F. [Detecting asthma in schools]. Arch Bronconeumol 2007; 42:561-3. [PMID: 17125689 DOI: 10.1016/s1579-2129(06)60587-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Thompson R, Delfino RJ, Tjoa T, Nussbaum E, Cooper D. Evaluation of daily home spirometry for school children with asthma: new insights. Pediatr Pulmonol 2006; 41:819-28. [PMID: 16847876 DOI: 10.1002/ppul.20449] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Home spirometers are useful for monitoring asthma therapy and for research, but the validity of maneuvers in children is in question. We evaluated the quality of PEF, FEV(1), and FVC data obtained from 67 children with persistent asthma who self-administered spirometry at home using the hand-held ndd EasyOne Frontline Spirometer with full expiratory curve data, electronic measurements of maneuver quality, and on-screen incentives. Half were studied in 2003 in one region, and half in 2004 in another region of Southern California. Subjects were followed at home weekly over 2 months and daily over 10 consecutive days. We retained completed spirometry sessions (9,916) consisting of three of six best maneuvers in the morning, afternoon, and evening. Percent compliance, software assessed repeatability and acceptability modified from American Thoracic Society criteria, and visually assessed quality of maneuvers, were compared across daily and weekly follow-up, study regions, and subject characteristics. Compliance was higher for daily (>90%) than for weekly follow-up (>84%), but not significantly different, and was consistent across subject characteristics. The number with two reproducible and acceptable maneuvers was significantly lower in the first than second region for daily (70 vs. 90%) and weekly follow-up (66 vs. 87%). Of 22,926 software accepted maneuvers, 1,944 (8.5%) were visually rejected (variable effort, cough, glottic closure). Maneuver quality was significantly lower for subjects age 9-12 versus 13-18 years, for subjects not taking anti-inflammatory medications, and for subjects with <80% predicted FEV(1). Longitudinal data collection is possible in children with asthma by employing repeated home training and follow-up, and using spirometers with built in quality assurance and incentive software. Region, age, and multiple indicators of persistent asthma, predict ability to perform reliable and accurate lung function maneuvers.
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Affiliation(s)
- Rohan Thompson
- Department of Medicine, Pediatric Pulmonology Division, Miller Children's Hospital, Long Beach, California,USA
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Song DJ, Woo CH, Kang H, Kim HJ, Choung JT. Applicability of interrupter resistance measurements for evaluation of exercise-induced bronchoconstriction in children. Pediatr Pulmonol 2006; 41:228-33. [PMID: 16429434 DOI: 10.1002/ppul.20340] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The interrupter technique is a noninvasive method for measuring air-flow resistance during tidal breathing. This method requires minimal cooperation, and is therefore promising for use in uncooperative children. The aim of this study was to evaluate applicability interrupter resistance (Rint) measurements in the assessment of exercise-induced bronchoconstriction (EIB). Fifty children aged 5-12 years with mild to moderate asthma were tested by exercise challenge, consisting of free outdoor running for 6 min at 80-90% of maximal predicted heart rate for age. Rint, forced expiratory volume in 1 sec (FEV1), and peak expiratory flow (PEF) were measured before and 10 min after exercise. EIB was defined as a fall of 10% or more in FEV1 after exercise. The repeatability of Rint was assessed, and its response to exercise challenge was compared with current standardized methods. The mean intermeasurement coefficient of variation was 4.6% (SD, +/- 3.0%), and the repeatability coefficient was 0.056 kPa/l/sec. Eighteen (36%) of the 50 children had EIB after exercise challenge test. The area under the receiver-operating characteristic (ROC) curve was 0.953 (95% confidence interval, 0.853-0.992; P < 0.001), and the optimal Rint cutoff value was 15.2%, producing a sensitivity of 88.9% and a specificity of 96.9%. The positive and negative predictive values were 94.1% and 93.9%, respectively. The kappa value between FEV1 and Rint was 0.83. The repeatability of Rint measurements was good, and the results of exercise challenge tests using Rint measurements have excellent agreement with the current standardized methods to detect EIB. Considering that only minimal comprehension and coordination are needed without forced breathing technique, the Rint measurement can provide a useful alternative for assessment of EIB in children unable to perform reliable spirometry.
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Affiliation(s)
- Dae Jin Song
- Department of Pediatrics, Korea University Medical College Hospital, Seoul, Korea
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Abstract
OBJECTIVE To discuss the different methods of assessing lung function measurements for the diagnosis of occupational asthma, focusing in particular on serial peak expiratory flow rate (PEFR) monitoring, including details on how PEFR records should be kept, plotted, and analyzed and limitations of the method. DATA SOURCES Published studies on the use of diagnostic methods in occupational asthma, expert opinion, and recently obtained data from studies performed at a large occupational lung disease clinic. STUDY SOURCES: The expert opinion of the author was used to select the relevant data for review. RESULTS Objective methods are necessary for the diagnosis of occupational asthma, since clinical history alone is not a satisfactory means of diagnosis. Serial PEFR monitoring has a high diagnostic sensitivity and specificity for occupational asthma and is more useful than evaluation of cross-shift change in forced expiratory volume in 1 second or change in nonspecific bronchial hyperresponsiveness. Interpretation is best performed by expert visual evaluation of plots of maximum, mean, and minimum daily PEFR readings. CONCLUSIONS Despite some limitations of the method, serial PEFR monitoring is usually the most appropriate first-line investigation in workers suspected of having occupational asthma.
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Affiliation(s)
- Wasif Anees
- Occupational Lung Disease Unit, Birmingham Heartlands Hospital, Bordesley Green East, Birmingham, England
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Abstract
Asthma can be affected by stress, anxiety, sadness, and suggestion, as well as by environmental irritants or allergens, exercise, and infection. It also is associated with an elevated prevalence of anxiety and depressive disorders. Asthma and these psychological states and traits may mutually potentiate each other through direct psychophysiological mediation, nonadherence to medical regimen, exposure to asthma triggers, and inaccuracy of asthma symptom perception. Defensiveness is associated with inaccurate perception of airway resistance and stress-related bronchoconstriction. Asthma education programs that teach about the nature of the disease, medications, and trigger avoidance tend to reduce asthma morbidity. Other promising psychological interventions as adjuncts to medical treatment include training in symptom perception, stress management, hypnosis, yoga, and several biofeedback procedures.
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Affiliation(s)
- Paul Lehrer
- Department of Psychiatry, Robert Wood Johnson Medical School, Piscataway, New Jersey 08854, USA.
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Smith CJ, Bombick DW, Ryan BA, Morton MJ, Doolittle DJ. Pulmonary function in nonsmokers following exposure to sidestream cigarette smoke. Toxicol Pathol 2001; 29:260-4. [PMID: 11421494 DOI: 10.1080/019262301317052549] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Ten healthy male and 10 healthy female, "never-smoking" subjects (ages 21-50) participated in a 5-day environmental room study to determine if an acute exposure to a high level of fresh diluted sidestream smoke (FDSS) would alter pulmonary function. On Monday, Tuesday, Thursday and Friday, the twenty subjects sat in an environmental room for 7.33 hours and were exposed to filtered and humidified air. On Wednesday, the twenty subjects were exposed in an environmental room for 7.33 hours to an average respirable suspended particle (RSP) concentration of 179 micrograms per m3 of FDSS generated by machine smoking Kentucky 1R4F reference cigarettes. This level of FDSS is 3.3 times the 95th percentile concentration of workplace environmental tobacco smoke exposure levels previously measured in the US. FVC and FEV1 decreased approximately 1.6% (p < 0.05) in both males and females after exposure. Similarly, PEF decreased approximately 1.3% (p < 0.03) following exposure. The observed decrease in pulmonary function was consistent with a "stress" related norepinephrine-induced alteration in blood flow leading to transient bronchoconstriction. Alternatively, a cholinergic reflex due to activation of bronchopulmonary C fibers may have also played a role in the transient bronchoconstriction. These small exposure-related decrements in pulmonary function were reversible.
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Affiliation(s)
- C J Smith
- Research and Development, Bowman Gray Technical Center, R. J. Reynolds Tobacco Company, Winston-Salem, NC 27102-1487, USA
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Abstract
The management of children with acute asthma remains a difficult and challenging process. Although newer asthma medications are being developed, they are unlikely to have a large impact on the management of children with acute asthma. The leukotriene inhibitors are new anti-inflammatory agents for asthma and are beneficial for the treatment of patients with chronic asthma but have no therapeutic effect during the acute phase of an exacerbation. Older treatments, including the use of magnesium and heliox, have been revisited. Although some children with severe asthma may respond, these do not provide relief for most children with acute exacerbation. The new challenge for asthma care is finding ways to link children with their primary care providers so that regular asthma care can be established. The NHLBI recommends that children with asthma have regular visits with their primary care providers (e.g., four times a year). Regular care results in better adherence to medical and preventive management plans and improves the relationship between patients and physicians. Instituting an asthma action plan, which instructs families on when and how to begin therapy for an acute exacerbation, may prevent progression to a more severe condition.
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Affiliation(s)
- S R Smith
- Division of Pediatric Emergency Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
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Weytjens K, Malo JL, Cartier A, Ghezzo H, Delwiche JP, Vandenplas O. Comparison of peak expiratory flows and FEV1 in assessing immediate asthmatic reactions due to occupational agents. Allergy 1999; 54:621-5. [PMID: 10435478 DOI: 10.1034/j.1398-9995.1999.t01-1-00105.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND FEV1 is more sensitive than PEF in assessing late asthmatic responses (LAR) after specific inhalation challenges (SIC) with occupational agents. As immediate asthmatic reactions (IAR) mainly involve proximal airways, PEF may, however, be as valid as FEV1. METHODS Thirty-seven subjects who experienced an immediate fall in FEV1 of > or =20% during SIC with occupational agents and 20 subjects with fall of < or =10% in FEV1 were included. Both FEV1 and PEF were measured in a random order every 10 min for 1 h after exposure. We corrected PEF (PEFc) for inaccuracies of the mini-Wright meters by the Miller equation. RESULTS Maximum changes in PEFc (30+/-11%) were not significantly different from changes in FEV1 (27+/-5%) (P=0.13). Their timings after exposure were 14+/-11 min and 17+/-17 min, respectively (P=0.4). High sensitivity (92%), specificity (95%), accuracy (93%), and positive predictive value (97%) were found for a 20% fall in PEFc to detect a significant IAR. Results were better and not influenced by meter inaccuracies with a cutoff point of 15% change in noncorrected PEF (PEFnc). An absolute decrease in PEF of 70 l/min gave a good discrimination between reactions with and without an asthmatic response. CONCLUSIONS PEF is as satisfactory as FEV1 for detecting a significant IAR after exposure to an occupational agent if one considers a cutoff point of 1) 15% fall in PEF 2) 20% fall in PEFc 3) 20% fall and/or 70 l/min decrease in PEFnc.
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Affiliation(s)
- K Weytjens
- Department of Chest Medicine, Hôpital du Sacré-Coeur, Montréal, Quebec, Canada
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