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Käck U, van Hage M, Grönlund H, Lilja G, Asarnoj A, Konradsen JR. Allergic sensitization to lipocalins reflects asthma morbidity in dog dander sensitized children. Clin Transl Allergy 2022; 12:e12149. [PMID: 35510076 PMCID: PMC9058535 DOI: 10.1002/clt2.12149] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Revised: 03/20/2022] [Accepted: 04/11/2022] [Indexed: 11/25/2022] Open
Abstract
Background Sensitization to dog is an important risk factor for asthma in children, but the clinical relevance of IgE to available dog‐ and furry animal allergen molecules is uncertain. Methods Spirometry, methacholine challenge, fraction of exhaled nitric oxide, nasal challenge with dog extract and questionnaires were performed in 59 dog‐sensitized children (age 10–18 years). Serum IgE to dog‐, cat‐, horse extracts and the allergen molecules Can f 1–6, Fel d 1, Fel d 2, Fel d 4 and Equ c 1 were evaluated. Results Median numbers of positive IgE results to furry animal allergen molecules among children without asthma was 3, with asthma 5.5 and with troublesome asthma 9 (asthma vs. no asthma; p = 0.039; troublesome asthma vs. no asthma; p = 0.009). The odds ratio for asthma if sensitized to any lipocalin was 7.2 (95% confidence Interval: 1.44–35.9). Children with troublesome asthma had higher IgE levels to the lipocalins Can f 2, Can f 4 and Can f 6 compared to the rest of the study population (44 vs. 4.1 kUA/L, p = 0.015; 5.8 vs. 0.9 kUA/L, p = 0.018 and 1.3 vs. 0.7 kUA/L, p = 0.03 respectively). Furthermore, a positive nasal challenge was more common among children with troublesome asthma (83% vs. 36%, p = 0.036). Conclusions Polysensitization to furry animal allergens and lipocalins is associated with asthma in dog‐sensitized children. Children with troublesome asthma have higher IgE levels to several dog lipocalins than other dog sensitized children. Key message Polysensitization to furry animal allergens and high IgE levels to the dog lipocalins Can f 2, Can f 4 and Can f 6 is associated with asthma severity in dog dander sensitized children. Molecular allergy diagnostics may thus help the clinicians to evaluate the impact of allergic sensitization on asthma morbidity.
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Affiliation(s)
- Ulrika Käck
- Department of Clinical Science and Education Södersjukhuset Karolinska Institutet Stockholm Sweden.,Sachs' Children and Youth Hospital Södersjukhuset Stockholm Sweden
| | - Marianne van Hage
- Department of Medicine Solna Division of Immunology and Allergy Karolinska Institutet and Karolinska University Hospital Stockholm Sweden
| | - Hans Grönlund
- Department of Clinical Neuroscience Karolinska Institutet Stockholm Sweden
| | - Gunnar Lilja
- Department of Clinical Science and Education Södersjukhuset Karolinska Institutet Stockholm Sweden.,Sachs' Children and Youth Hospital Södersjukhuset Stockholm Sweden
| | - Anna Asarnoj
- Astrid Lindgren Children's Hospital Karolinska University Hospital Stockholm Sweden.,Department of Women's and Children's Health Karolinska Institutet Stockholm Sweden
| | - Jon R Konradsen
- Astrid Lindgren Children's Hospital Karolinska University Hospital Stockholm Sweden.,Department of Women's and Children's Health Karolinska Institutet Stockholm Sweden
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2
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Identifying bronchoconstriction from the ratio of diaphragm EMG to tidal volume. Respir Physiol Neurobiol 2021; 291:103692. [PMID: 34020067 DOI: 10.1016/j.resp.2021.103692] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 05/09/2021] [Accepted: 05/16/2021] [Indexed: 11/21/2022]
Abstract
BACKGROUND A fall of ≥ 20 % in forced expiratory volume in the first second (FEV1) with a cumulative dose of histamine ≤ 7.8 μmol is considered to indicate bronchial hyperactivity, but no method exists for patients who cannot perform spirometry properly. Here we hypothesized that increases in respiratory central output measured by chest wall electromyography of the diaphragm (EMGdi-c) expressed as a function of tidal volume (EMGdi-c/VT) would have discriminative power to detect a 'positive' challenge test. METHODS In a physiological study EMGdi was recorded from esophageal electrode (EMGdi-e) in 16 asthma patients and 16 healthy subjects during a histamine challenge test. In a second study, EMGdi from chest wall surface electrodes (EMGdi-c) was measured during a histamine challenge in 44 asthma patients and 51 healthy subjects. VT was recorded from a digital flowmeter during both studies. RESULTS With histamine challenge test the change in EMGdi-e/VT in patients with asthma was significantly higher than that in healthy subjects (104.2 % ± 48.6 % vs 0.03 % ± 17.1 %, p < 0.001). Similarly there was a significant difference in the change of EMGdi-c/VT between patients with asthma and healthy subjects (90.5 % ± 75.5 % vs 2.4 % ± 21.7 %, p < 0.001). At the optimal cut-off point (29 % increase in EMGdi-c/VT), the area under the ROC curve (AUC) for detection of a positive test was 0.91 (p < 0.001) with sensitivity 86 % and specificity 92 %. CONCLUSIONS We conclude that EMGdi-c/VT may be used as an alternative for the assessment of bronchial hypersensitivity and airway reversibility to differentiate patients with asthma from healthy subjects.
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3
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Akgündüz Üzmezoğlu B. Inhalation Challenge Tests in Occupational Asthma: Why Are Multiple Tests Needed? Turk Thorac J 2021; 22:154-162. [PMID: 33871340 DOI: 10.5152/turkthoracj.2021.20007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 02/16/2020] [Indexed: 11/22/2022]
Abstract
Occupational and environmental lung diseases are on the rise because of the widespread use of various toxic agents in industry. Asthma etiopathogenesis is unclear because of exposure to high and low molecular agents in workplaces. Approximately 15-25% of asthma in adults is reported to be related to occupational exposure. The prevalence of occupational asthma (OA) is predicted to be high. The difficulties in diagnosing OA results in inadequate treatment, permanent airway damage, and medicolegal and social problems. As with other occupational diseases, it is necessary to demonstrate a direct causal relationship between the suspected agent and OA. Spirometry, peak expiratory flow rate, and/or non-specific bronchial hyperresponsiveness are frequently used to show airway hyperresponsiveness at the workplace and away from work. However, there are some controversies about the specificity and sensitivity of these test methods. Furthermore, these tests do not identify the exposure agent, which could be the causative agent. Specific inhalation challenge (SIC) tests that demonstrate the direct causal relationship are currently the gold standard. However, their positive and negative predictive values have not yet been established; therefore, many low molecular weight agents could cause late or atypical reactions. Therefore, a negative SIC test cannot exclude the disease. This review describes the procedures for the SIC test and discusses the importance of using the combined test methods with the SIC test.
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Affiliation(s)
- Bilge Akgündüz Üzmezoğlu
- Department of Occupational Diseases, Atatürk Chest Diseases and Thoracic Surgery Education and Research Hospital, Ankara, Turkey
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4
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Nilsen K, Thompson BR, Zajakovski N, Kean M, Harris B, Cowin G, Robinson P, Prisk GK, Thien F. Airway closure is the predominant physiological mechanism of low ventilation seen on hyperpolarized helium-3 MRI lung scans. J Appl Physiol (1985) 2020; 130:781-791. [PMID: 33332988 DOI: 10.1152/japplphysiol.00163.2020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Hyperpolarized helium-3 MRI (3He MRI) provides detailed visualization of low- (hypo- and non-) ventilated lungs. Physiological measures of gas mixing may be assessed by multiple breath nitrogen washout (MBNW) and of airway closure by a forced oscillation technique (FOT). We hypothesize that in patients with asthma, areas of low-ventilated lung on 3He MRI are the result of airway closure. Ten control subjects, ten asthma subjects with normal spirometry (non-obstructed), and ten asthmatic subjects with reduced baseline lung function (obstructed) attended two testing sessions. On visit one, baseline plethysmography was performed followed by spirometry, MBNW, and FOT assessment pre and post methacholine challenge. On visit two, 3He MRI scans were conducted pre and post methacholine challenge. Post methacholine the volume of low-ventilated lung increased from 8.3% to 13.8% in the non-obstructed group (P = 0.012) and from 13.0% to 23.1% in the obstructed group (P = 0.001). For all subjects, the volume of low ventilation from 3He MRI correlated with a marker of airway closure in obstructive subjects, Xrs (6 Hz) and the marker of ventilation heterogeneity Scond with r2 values of 0.61 (P < 0.001) and 0.56 (P < 0.001), respectively. The change in Xrs (6 Hz) correlated well (r2 = 0.45, p < 0.001), whereas the change in Scond was largely independent of the change in low ventilation volume (r2 = 0.13, P < 0.01). The only significant predictor of low ventilation volume from the multi-variate analysis was Xrs (6 Hz). This is consistent with the concept that regions of poor or absent ventilation seen on 3He MRI are primarily the result of airway closure.NEW & NOTEWORTHY This study introduces a novel technique of generating high-resolution 3D ventilation maps from hyperpolarized helium-3 MRI. It is the first study to demonstrate that regions of poor or absent ventilation seen on 3He MRI are primarily the result of airway closure.
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Affiliation(s)
- Kris Nilsen
- The Alfred Hospital, Melbourne, Australia.,Swinburne University of Technology, Melbourne, Australia
| | - Bruce R Thompson
- Swinburne University of Technology, Melbourne, Australia.,Monash University, Melbourne, Australia
| | | | - Michael Kean
- The Royal Children's Hospital, Melbourne, Australia
| | - Benjamin Harris
- University of Sydney, Sydney, Australia.,Respiratory Medicine, Royal North Shore Hospital, Sydney, Australia
| | - Gary Cowin
- National Imaging Facility, Centre for Advanced Imaging, The University of Queensland, Brisbane, Australia
| | - Phil Robinson
- The Royal Children's Hospital, Melbourne, Australia.,University of Melbourne, Melbourne, Australia.,Murdoch Children's Research Institute, Melbourne, Australia
| | - G Kim Prisk
- University of California, San Diego, California
| | - Francis Thien
- Monash University, Melbourne, Australia.,Box Hill Hospital, Eastern Health, Melbourne, Australia
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5
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Konradsen JR, Grundström J, Hellkvist L, Tran TAT, Andersson N, Gafvelin G, Kiewiet MBG, Hamsten C, Tang J, Parkin RV, Shamji MH, Hedlin G, Cardell LO, van Hage M. Intralymphatic immunotherapy in pollen-allergic young adults with rhinoconjunctivitis and mild asthma: A randomized trial. J Allergy Clin Immunol 2019; 145:1005-1007.e7. [PMID: 31775016 DOI: 10.1016/j.jaci.2019.11.017] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 11/04/2019] [Accepted: 11/15/2019] [Indexed: 10/25/2022]
Affiliation(s)
- Jon R Konradsen
- Department of Medicine Solna, Division of Immunology and Allergy, Karolinska Institutet and University Hospital, Stockholm, Sweden; Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden; Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
| | - Jeanette Grundström
- Department of Medicine Solna, Division of Immunology and Allergy, Karolinska Institutet and University Hospital, Stockholm, Sweden
| | - Laila Hellkvist
- Division of ENT Diseases, Department of Clinical Sciences, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden; Department of ENT Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Thi Anh Thu Tran
- Department of Medicine Solna, Division of Immunology and Allergy, Karolinska Institutet and University Hospital, Stockholm, Sweden
| | - Niklas Andersson
- Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Guro Gafvelin
- Therapeutic Immune Design Unit, Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - M B Gea Kiewiet
- Department of Medicine Solna, Division of Immunology and Allergy, Karolinska Institutet and University Hospital, Stockholm, Sweden
| | - Carl Hamsten
- Department of Medicine Solna, Division of Immunology and Allergy, Karolinska Institutet and University Hospital, Stockholm, Sweden
| | - Jiaqian Tang
- Immunomodulation and Tolerance Group, Allergy and Clinical Immunology, Section of Inflammation, Repair and Development, National Heart and Lung Institute, Imperial College, London, United Kingdom; MRC & Asthma UK Centre in Allergic Mechanisms of Asthma, London, United Kingdom
| | - Rebecca V Parkin
- Immunomodulation and Tolerance Group, Allergy and Clinical Immunology, Section of Inflammation, Repair and Development, National Heart and Lung Institute, Imperial College, London, United Kingdom; MRC & Asthma UK Centre in Allergic Mechanisms of Asthma, London, United Kingdom
| | - Mohamed H Shamji
- Immunomodulation and Tolerance Group, Allergy and Clinical Immunology, Section of Inflammation, Repair and Development, National Heart and Lung Institute, Imperial College, London, United Kingdom; MRC & Asthma UK Centre in Allergic Mechanisms of Asthma, London, United Kingdom
| | - Gunilla Hedlin
- Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden; Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden
| | - Lars-Olaf Cardell
- Division of ENT Diseases, Department of Clinical Sciences, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden; Department of ENT Diseases, Karolinska University Hospital, Stockholm, Sweden
| | - Marianne van Hage
- Department of Medicine Solna, Division of Immunology and Allergy, Karolinska Institutet and University Hospital, Stockholm, Sweden.
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Tonga KO, Chapman DG, Farah CS, Oliver BG, Zimmermann SC, Milne S, Sanai F, Jetmalani K, Berend N, Thamrin C, King GG. Reduced lung elastic recoil and fixed airflow obstruction in asthma. Respirology 2019; 25:613-619. [PMID: 31482693 DOI: 10.1111/resp.13688] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 07/01/2019] [Accepted: 08/07/2019] [Indexed: 11/27/2022]
Abstract
BACKGROUND AND OBJECTIVE Fixed airflow obstruction (FAO) in asthma occurs despite optimal inhaled treatment and no smoking history, and remains a significant problem, particularly with increasing age and duration of asthma. Increased lung compliance and loss of lung elastic recoil has been observed in older people with asthma, but their link to FAO has not been established. We determined the relationship between abnormal lung elasticity and airflow obstruction in asthma. METHODS Non-smoking asthmatic subjects aged >40 years, treated with 2 months of high-dose inhaled corticosteroid/long-acting beta-agonist (ICS/LABA), had FAO measured by spirometry, and respiratory system resistance at 5 Hz (Rrs5 ) and respiratory system reactance at 5 Hz (Xrs5 ) measured by forced oscillation technique. Lung compliance (K) and elastic recoil (B/A) were calculated from pressure-volume curves measured by an oesophageal balloon. Linear correlations between K and B/A, and forced expiratory volume in 1 s/forced vital capacity (FEV1 /FVC), Rrs5 and Xrs5 were assessed. RESULTS Eighteen subjects (11 males; mean ± SD age: 64 ± 8 years, asthma duration: 39 ± 22 years) had moderate FAO measured by spirometry ((mean ± SD z-score) post-bronchodilator FEV1 : -2.2 ± 0.5, FVC: -0.7 ± 1.0, FEV1 /FVC: -2.6 ± 0.7) and by increased Rrs5 (median (IQR) z-score) 2.7 (1.9 to 3.2) and decreased Xrs5 : -4.1(-2.4 to -7.3). Lung compliance (K) was increased in 9 of 18 subjects and lung elastic recoil (B/A) reduced in 5 of 18 subjects. FEV1 /FVC correlated negatively with K (rs = -0.60, P = 0.008) and Rrs5 correlated negatively with B/A (rs = -0.52, P = 0.026), independent of age. Xrs5 did not correlate with lung elasticity indices. CONCLUSION Increased lung compliance and loss of elastic recoil relate to airflow obstruction in older non-smoking asthmatic subjects, independent of ageing. Thus, structural lung tissue changes may contribute to persistent, steroid-resistant airflow obstruction. CLINICAL TRIAL REGISTRATION ACTRN126150000985583 at anzctr.org.au (UTN: U1111-1156-2795).
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Affiliation(s)
- Katrina O Tonga
- The Department of Respiratory Medicine, Royal North Shore Hospital, Sydney, NSW, Australia.,Airway Physiology and Imaging Group and the Woolcock Emphysema Centre, The Woolcock Institute of Medical Research, Sydney, NSW, Australia.,Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,The Department of Respiratory Medicine, Concord Hospital, Sydney, NSW, Australia.,The Department of Thoracic and Lung Transplant Medicine, St Vincent's Hospital, Sydney, NSW, Australia.,St Vincent's Clinical School, Faculty of Medicine, The University of New South Wales, Sydney, NSW, Australia
| | - David G Chapman
- Airway Physiology and Imaging Group and the Woolcock Emphysema Centre, The Woolcock Institute of Medical Research, Sydney, NSW, Australia.,Discipline of Medical Sciences, School of Life Sciences, University of Technology Sydney, Sydney, NSW, Australia
| | - Claude S Farah
- Airway Physiology and Imaging Group and the Woolcock Emphysema Centre, The Woolcock Institute of Medical Research, Sydney, NSW, Australia.,Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,The Department of Respiratory Medicine, Concord Hospital, Sydney, NSW, Australia.,Faculty of Medicine and Health Sciences, Macquarie University, Sydney, NSW, Australia
| | - Brian G Oliver
- Airway Physiology and Imaging Group and the Woolcock Emphysema Centre, The Woolcock Institute of Medical Research, Sydney, NSW, Australia.,Discipline of Medical Sciences, School of Life Sciences, University of Technology Sydney, Sydney, NSW, Australia
| | - Sabine C Zimmermann
- The Department of Respiratory Medicine, Royal North Shore Hospital, Sydney, NSW, Australia.,Airway Physiology and Imaging Group and the Woolcock Emphysema Centre, The Woolcock Institute of Medical Research, Sydney, NSW, Australia.,Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,The Department of Respiratory Medicine, Concord Hospital, Sydney, NSW, Australia
| | - Stephen Milne
- The Department of Respiratory Medicine, Royal North Shore Hospital, Sydney, NSW, Australia.,Airway Physiology and Imaging Group and the Woolcock Emphysema Centre, The Woolcock Institute of Medical Research, Sydney, NSW, Australia.,Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,The Department of Respiratory Medicine, Concord Hospital, Sydney, NSW, Australia
| | - Farid Sanai
- Airway Physiology and Imaging Group and the Woolcock Emphysema Centre, The Woolcock Institute of Medical Research, Sydney, NSW, Australia.,Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,Discipline of Medical Sciences, School of Life Sciences, University of Technology Sydney, Sydney, NSW, Australia
| | - Kanika Jetmalani
- Airway Physiology and Imaging Group and the Woolcock Emphysema Centre, The Woolcock Institute of Medical Research, Sydney, NSW, Australia
| | - Norbert Berend
- Airway Physiology and Imaging Group and the Woolcock Emphysema Centre, The Woolcock Institute of Medical Research, Sydney, NSW, Australia.,Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,St Vincent's Clinical School, Faculty of Medicine, The University of New South Wales, Sydney, NSW, Australia.,Respiratory Research Group, The George Institute for Global Health, Sydney, NSW, Australia
| | - Cindy Thamrin
- Airway Physiology and Imaging Group and the Woolcock Emphysema Centre, The Woolcock Institute of Medical Research, Sydney, NSW, Australia.,Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia
| | - Gregory G King
- The Department of Respiratory Medicine, Royal North Shore Hospital, Sydney, NSW, Australia.,Airway Physiology and Imaging Group and the Woolcock Emphysema Centre, The Woolcock Institute of Medical Research, Sydney, NSW, Australia.,Faculty of Medicine and Health, The University of Sydney, Sydney, NSW, Australia.,NHMRC Centre of Excellence in Severe Asthma, Newcastle, NSW, Australia
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Cockcroft DW, Davis BE, Blais CM. Direct bronchoprovocation test methods: history 1945-2018. Expert Rev Respir Med 2019; 13:279-289. [PMID: 30632426 DOI: 10.1080/17476348.2019.1568245] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
INTRODUCTION Bronchoprovocation inhalation challenge tests with direct acting stimuli (e.g. methacholine) are widely used clinically to aid in the diagnosis of asthma. Areas covered: The history of direct challenges with histamine and muscarinic agonists is reviewed. This began with parenteral administration of stimuli with responses monitored clinically and by VC, progressing to inhalation dose-response challenges monitored by FEV1 and FEV1/VC ratio, both (the challenge method and the technology to measure FEV1) developed by Robert Tiffeneau in the mid-1940s. Careful standardization of methods has become appreciated albeit after-the-fact. Recent guidelines recommend standardizing the methacholine PD20 at 400 μg above which a methacholine challenge is considered negative. CONCLUSIONS The methacholine inhalation test is highly sensitive for a diagnosis of current asthma when symptoms under evaluation are clinically current and when methacholine is inhaled without deep inhalations. Under these circumstances, a methacholine PD20 > 400 μg excludes current asthma with reasonable certainty. PD20 values >25 μg and ≤400 μg will have a variable specificity and positive predictive value for asthma which increases the lower the PD20 and the higher the pre-test probability for a diagnosis of asthma. A PD20 ≤25 μg has high specificity and low sensitivity for asthma.
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Affiliation(s)
- Donald W Cockcroft
- a Division of Respirology, Critical Care and Sleep Medicine, Department of Medicine , University of Saskatchewan
| | - Beth E Davis
- a Division of Respirology, Critical Care and Sleep Medicine, Department of Medicine , University of Saskatchewan
| | - Christianne M Blais
- a Division of Respirology, Critical Care and Sleep Medicine, Department of Medicine , University of Saskatchewan
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8
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Shaw RA, Crane J, O'Donnell TV, Lewis ME, Stewart B, Beasley R. The use of a videotaped questionnaire for studying asthma prevalence. Med J Aust 2019. [DOI: 10.5694/j.1326-5377.1992.tb137182.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Robyn A Shaw
- Wellington School of Medicine, PO Box 7343, Wellington South, New Zealand
| | - Julian Crane
- Wellington School of Medicine, PO Box 7343, Wellington South, New Zealand
| | - Thomas V O'Donnell
- Wellington School of Medicine, PO Box 7343, Wellington South, New Zealand
| | - Margaret E Lewis
- Wellington School of Medicine, PO Box 7343, Wellington South, New Zealand
| | - Ben Stewart
- Wellington School of Medicine, PO Box 7343, Wellington South, New Zealand
| | - Richard Beasley
- Wellington School of Medicine, PO Box 7343, Wellington South, New Zealand
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9
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Bernholm KF, Homøe AS, Meteran H, Jensen CB, Porsbjerg C, Backer V. F eNO-based asthma management results in faster improvement of airway hyperresponsiveness. ERJ Open Res 2018; 4:00147-2017. [PMID: 30302333 PMCID: PMC6168761 DOI: 10.1183/23120541.00147-2017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Accepted: 08/03/2018] [Indexed: 11/05/2022] Open
Abstract
Asthma is characterised by inflammation and respiratory symptoms. Current asthma treatment is based on severity of asthma symptoms only. Exhaled nitric oxide fraction (F eNO) is not recommended by the Global Initiative for Asthma guidelines. The aim was to compare the usefulness of a F eNO guided versus symptom-based treatment in achieving improved asthma control assessed by airway hyperresponsiveness (AHR). 80 asthmatic patients were included in a double-blinded, parallel, randomised controlled trial with follow-up visits after 8, 24 and 36 weeks. Treatment was tailored using either a F eNO or Asthma Control Questionnaire (ACQ) based algorithm. Inclusion criteria were asthma symptoms and a provocative dose causing a 15% fall in forced expiratory volume in 1 s <635 mg mannitol. At each visit AHR, F eNO, ACQ and blood tests were performed. No differences between the two groups were found at inclusion. AHR from 8 to 24 weeks was improved in the F eNO group compared to the ACQ group (response dose ratio (RDR) geometric mean (95% CI): 0.02 (0.01-0.04) versus 0.05 (0.03-0.07), respectively, p=0.015). AHR to mannitol at 36 weeks showed no differences between the two groups (mean difference RDR (95% CI): -0.02 (-0.05-0.02), p=0.3). Total doses of inhaled steroid and number of exacerbations were similar (p>0.05). When using F eNO as a treatment management tool, lowering of airway responsiveness occurred earlier than using ACQ. However, airway responsiveness and asthma control after 9 months were similar.
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Affiliation(s)
- Katrine Feldballe Bernholm
- Respiratory Research Unit, Dept of Respiratory Medicine, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Anne-Sophie Homøe
- Respiratory Research Unit, Dept of Respiratory Medicine, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Howraman Meteran
- Respiratory Research Unit, Dept of Respiratory Medicine, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Camilla Bjørn Jensen
- Center for Research and Disease Prevention, Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark
| | - Celeste Porsbjerg
- Respiratory Research Unit, Dept of Respiratory Medicine, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Vibeke Backer
- Respiratory Research Unit, Dept of Respiratory Medicine, Bispebjerg University Hospital, Copenhagen, Denmark
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10
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Validation of ATS clinical practice guideline cut-points for FeNO in asthma. Respir Med 2018; 144:22-29. [PMID: 30366580 DOI: 10.1016/j.rmed.2018.09.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 09/15/2018] [Accepted: 09/19/2018] [Indexed: 11/20/2022]
Abstract
BACKGROUND The American Thoracic society (ATS) has suggested using fractional exhaled nitric oxide (FeNO) to monitor the level of eosinophilic (EOS) airway inflammation in asthma, but validation of the proposed cut-points is required in real-life populations. OBJECTIVE To validate FeNO cut-points suggested by ATS in relation to sputum EOS count in a real life population of asthma patients. METHODS All patients referred consecutively over a 12-months period for specialist assessment of asthma, were examined with FeNO and induced sputum, and re-examined 12 months later. The predicted values of a positive and a negative test (PPV and NPV) for a cut off ≥3% EOS in sputum were calculated. Change in FeNO was defined in accordance with ATS (>20% or 10 ppb if FeNO was <50 ppb). RESULTS 144 adult asthma patients were examined (59% female). Low FeNO (<25 ppb) at baseline was found in 94 (65%), FeNO between 25 and 50 ppb in 34 (24%) subjects and high FeNO >50 ppb in 16 (11%) subjects. The PPV for FeNO >25 ppb and >50 ppb to predict EOS ≥3% was 45% and 77%, NPV was 88% and 83%. The sensitivity decreased from 70% to 37% at the >50 ppb cut-off. A significant reduction in FeNO was associated with a reduction in sputum EOS (p = 0.01). CONCLUSION The findings support the validity of the FeNO cut-points suggested by ATS to monitor eosinophilic airway inflammation in asthma. However, in this real-life population, a large proportion of patients had intermediate FeNO values, which may limit the clinical usefulness of the ATS FeNO cut-points.
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11
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Aggarwal B, Mulgirigama A, Berend N. Exercise-induced bronchoconstriction: prevalence, pathophysiology, patient impact, diagnosis and management. NPJ Prim Care Respir Med 2018; 28:31. [PMID: 30108224 PMCID: PMC6092370 DOI: 10.1038/s41533-018-0098-2] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 07/05/2018] [Accepted: 07/11/2018] [Indexed: 11/30/2022] Open
Abstract
Exercise-induced bronchoconstriction (EIB) can occur in individuals with and without asthma, and is prevalent among athletes of all levels. In patients with asthma, symptoms of EIB significantly increase the proportion reporting feelings of fearfulness, frustration, isolation, depression and embarrassment compared with those without symptoms. EIB can also prevent patients with asthma from participating in exercise and negatively impact their quality of life. Diagnosis of EIB is based on symptoms and spirometry or bronchial provocation tests; owing to low awareness of EIB and lack of simple, standardised diagnostic methods, under-diagnosis and mis-diagnosis of EIB are common. To improve the rates of diagnosis of EIB in primary care, validated and widely accepted symptom-based questionnaires are needed that can accurately replicate the current diagnostic standards (forced expiratory volume in 1 s reductions observed following exercise or bronchoprovocation challenge) in patients with and without asthma. In patients without asthma, EIB can be managed by various non-pharmacological methods and the use of pre-exercise short-acting β2-agonists (SABAs). In patients with asthma, EIB is often associated with poor asthma control but can also occur in individuals who have good control when not exercising. Inhaled corticosteroids are recommended when asthma control is suboptimal; however, pre-exercise SABAs are also widely used and are recommended as the first-line therapy. This review describes the burden, key features, diagnosis and current treatment approaches for EIB in patients with and without asthma and serves as a call to action for family physicians to be aware of EIB and consider it as a potential diagnosis.
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Affiliation(s)
- Bhumika Aggarwal
- Respiratory, Global Classic & Established Products, GSK, Singapore, Singapore.
| | - Aruni Mulgirigama
- Respiratory, Global Classic & Established Products, GSK, Middlesex, London, UK
| | - Norbert Berend
- Global Respiratory Franchise, GSK, Middlesex, London, UK
- George Institute for Global Health, Newtown, NSW, Australia
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12
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Anderson SD. Repurposing drugs as inhaled therapies in asthma. Adv Drug Deliv Rev 2018; 133:19-33. [PMID: 29906501 DOI: 10.1016/j.addr.2018.06.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 05/26/2018] [Accepted: 06/06/2018] [Indexed: 01/06/2023]
Abstract
For the first 40 years of the 20th century treatment for asthma occurred in response to an asthma attack. The treatments were given by injection or orally and included the adrenergic agonists adrenalin/epinephrine and ephedrine and a phosphodiesterase inhibitor theophylline. Epinephrine became available as an aerosol in 1930. After 1945, isoprenaline, a non-selective beta agonist, became available for oral use but it was most widely used by inhalation. Isoprenaline was short-acting with unwanted cardiac effects. More selective beta agonists, with a longer duration of action and fewer side-effects became available, including orciprenaline in 1967, salbutamol in 1969 and terbutaline in 1970. The inhaled steroid beclomethasone was available by 1972 and budesonide by 1982. Spirometry alone and in response to exercise was used to assess efficacy and duration of action of these drugs for the acute benefits of beta2 agonists and the chronic benefits of corticosteroids. Early studies comparing oral and aerosol beta2 agonists found equivalence in bronchodilator effect but the aerosol treatment was superior in preventing exercise-induced bronchoconstriction. Inhaled drugs are now widely used including the long-acting beta2 agonists, salmeterol and formoterol, and the corticosteroids, fluticasone, ciclesonide, mometasone and triamcinolone, that act locally and have low systemic bio-availability. Repurposing drugs as inhaled therapies permitted direct delivery of low doses of drug to the site of action reducing the incidence of unwanted side-effects and permitting the prophylactic treatment of asthma.
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Affiliation(s)
- Sandra D Anderson
- Clinical Professor, Central Clinical School, Sydney Medical School, University of Sydney, Sydney, NSW 2006, Australia.
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13
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Owens L, Laing IA, Zhang G, Turner S, Le Souëf PN. Airway function in infancy is linked to airflow measurements and respiratory symptoms from childhood into adulthood. Pediatr Pulmonol 2018; 53:1082-1088. [PMID: 29806178 DOI: 10.1002/ppul.24062] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Revised: 04/10/2018] [Accepted: 05/08/2018] [Indexed: 11/07/2022]
Abstract
INTRODUCTION Increasing evidence suggests that poor lung function in adulthood is determined very early in life. Our study aims were: (1) identify factors associated with early infant lung function; (2) quantify the link between early infant lung function and early adult lung function; and (3) identify environmental and inherited factors which predict lung function throughout the post-natal growth period. METHODS In this longitudinal study, 253 individuals were recruited antenatally. Lung function and allergy testing occurred at 1, 6, 12 months, 6, 11, 18, and 24 years of age. The relationship between lung function at 1 month (V'maxFRC) and spirometry variables at each follow-up was evaluated. Early life predictors of spirometry were assessed longitudinally using linear mixed models. RESULTS V'maxFRC correlated positively with FEF25-75% at every assessment from 6 to 24 years and FEV1 /FVC at 11 and 24 years and inversely with airway responsiveness at 6 and 18 years. Maternal asthma and smoking in pregnancy were associated with lower FEV1 from 6 to 24 years (-99 mL, P = 0.03; -77 mL, P = 0.045 respectively). Lower V'maxFRC at 1 month was associated with asthma and wheeze through to 24 years. CONCLUSION Lung airflow measurements track from birth into early adulthood, suggesting a permanent and stable airway framework is laid down in the antenatal period. Lower infant airway function is associated with respiratory symptoms into adulthood, indicating the link is clinically important. Antenatal and early life exposures must be addressed in order to maximize airway growth and reduce lifelong respiratory compromise.
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Affiliation(s)
- Louisa Owens
- School of Medicine University of Western Australia, Perth, Australia
- School of Women's and Children's Health, University of New South Wales, Australia
| | - Ingrid A Laing
- Telethon Kids Institute, Subiaco, Western Australia, Australia
- School of Biomedical Sciences, University of Western Australia, Perth, Australia
| | - Guicheng Zhang
- School of Public Health, Curtin University, Bentley, Western Australia, Australia
- Centre for Genetic Origins of Health and Disease, University of Western Australia and Curtin University
| | - Steve Turner
- School of Medical Sciences, University of Aberdeen, Aberdeen, Scotland
| | - Peter N Le Souëf
- School of Medicine University of Western Australia, Perth, Australia
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Burge PS, Moore VC, Robertson AS, Walters GI. Do laboratory challenge tests for occupational asthma represent what happens in the workplace? Eur Respir J 2018; 51:13993003.00059-2018. [PMID: 29748310 DOI: 10.1183/13993003.00059-2018] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 05/02/2018] [Indexed: 11/05/2022]
Abstract
Specific inhalation challenge (SIC) is the diagnostic reference standard for occupational asthma; however, a positive test cannot be considered truly significant unless it can be reproduced by usual work exposures. We have compared the timing and responses during SIC in hospital to Oasys analysis of serial peak expiratory flow (PEF) during usual work exposures.All workers with a positive SIC to occupational agents between 2006 and 2015 were asked to measure PEF every 2 h from waking to sleeping for 4 weeks during usual occupational exposures. Responses were compared between the laboratory challenge and the real-world exposures at work.All 53 workers with positive SIC were included. 49 out of 53 had records suitable for Oasys analysis, 14 required more than one attempt and all confirmed occupational work-related changes in PEF. Immediate SIC reactors and deterioration within the first 2 h of starting work were significantly correlated with early recovery, and late SIC reactors and a delayed start to workplace deterioration were significantly correlated with delayed recovery. Dual SIC reactions had features of immediate or late SIC reactions at work rather than dual reactions.The concordance of timings of reactions during SIC and at work provides further validation for the clinical significance of each test.
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Affiliation(s)
- P Sherwood Burge
- Occupational Lung Disease Unit, Birmingham Heartlands Hospital, Birmingham, UK
| | - Vicky C Moore
- Occupational Lung Disease Unit, Birmingham Heartlands Hospital, Birmingham, UK
| | | | - Gareth I Walters
- Occupational Lung Disease Unit, Birmingham Heartlands Hospital, Birmingham, UK
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Laurence C, van der Merwe L, Zhang G, Le Souëf P, Levin M. Association between pro-inflammatory alleles and allergic phenotypes in Xhosa adolescents. Pediatr Allergy Immunol 2018; 29:311-317. [PMID: 29314322 DOI: 10.1111/pai.12859] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 12/15/2017] [Indexed: 12/16/2022]
Abstract
BACKGROUND Significant differences exist in the prevalence, spectrum, and severity of allergic diseases between developing and developed countries and between subpopulations within single countries. These discrepancies likely result from a complex interaction between genetic and environmental factors. However, the precise nature of the contribution of ethnicity to genetic differences in the predisposition to allergic disease is not yet fully understood. In particular, there is a paucity of literature regarding the genetic determinants of allergic disease in people of black African origin with little or no genetic admixture. OBJECTIVE We aimed to analyze associations between 27 single nucleotide polymorphisms (SNPs) and allergy phenotypes in the local Xhosa population. METHODS A convenience sample of 213 Xhosa teenagers was enrolled at a local high school. Phenotypic data were collected in the form of a symptom questionnaire, skin prick tests for common food and aeroallergens, total serum IgE, and IgE to Ascaris lumbricoides. In addition, genotyping was performed to establish the prevalence of putative pro-inflammatory alleles. RESULTS We demonstrated several significant associations between polymorphisms and allergy phenotypes. In particular, 2 polymorphisms in the IL-10 gene (IL10 -592A>C and IL10 -1082A>G) and 1 in the IL-4 gene (IL4 -589C>T) showed multiple associations with allergic sensitization and asthma phenotypes. Other polymorphisms, across a multitude of genes with discrepant functions, showed less consistent associations. CONCLUSION This study represents an important first step in genotype/phenotype association in this population. Further research is required to confirm or refute our findings.
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Affiliation(s)
- Craig Laurence
- Department of Paediatrics and Child Health, Red CrossWar Memorial Children's Hospital, University of Cape Town, Cape Town, South Africa
| | - Lize van der Merwe
- Statistics Department, University of Western Cape, Cape Town, South Africa
| | - Guicheng Zhang
- School of Public Health, Curtin University, Perth, WA, Australia
| | - Peter Le Souëf
- School of Paediatrics and Child Health, Faculty of Medicine, Dentistry and Health Sciences, University of Western Australia, Perth, WA, Australia.,Department of Respiratory Medicine, Princess Margaret Hospital for Children, Red Cross War Memorial Children's Hospital, University of Cape Town, Cape Town, South Africa
| | - Michael Levin
- Division of Allergology, Red Cross War Memorial Children's Hospital, University of Cape Town, Cape Town, South Africa
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Abstract
Being born preterm often adversely affects later lung function. Airway obstruction and bronchial hyperresponsiveness (BHR) are common findings. Respiratory symptoms in asthma and in lung disease after preterm birth might appear similar, but clinical experience and studies indicate that symptoms secondary to preterm birth reflect a separate disease entity. BHR is a defining feature of asthma, but can also be found in other lung disorders and in subjects without respiratory symptoms. We review different methods to assess BHR, and findings reported from studies that have investigated BHR after preterm birth. The area appeared understudied with relatively few and heterogeneous articles identified, and lack of a pervasive understanding. BHR seemed related to low gestational age at delivery and a neonatal history of bronchopulmonary dysplasia. No studies reported associations between BHR after preterm birth and the markers of eosinophilic inflammatory airway responses typically found in asthma. This should be borne in mind when treating preterm born individuals with BHR and airway symptoms.
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17
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Devos FC, Maaske A, Robichaud A, Pollaris L, Seys S, Lopez CA, Verbeken E, Tenbusch M, Lories R, Nemery B, Hoet PH, Vanoirbeek JA. Forced expiration measurements in mouse models of obstructive and restrictive lung diseases. Respir Res 2017. [PMID: 28629359 PMCID: PMC5477381 DOI: 10.1186/s12931-017-0610-1] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Background Pulmonary function measurements are important when studying respiratory disease models. Both resistance and compliance have been used to assess lung function in mice. Yet, it is not always clear how these parameters relate to forced expiration (FE)-related parameters, most commonly used in humans. We aimed to characterize FE measurements in four well-established mouse models of lung diseases. Method Detailed respiratory mechanics and FE measurements were assessed concurrently in Balb/c mice, using the forced oscillation and negative pressure-driven forced expiration techniques, respectively. Measurements were performed at baseline and following increasing methacholine challenges in control Balb/c mice as well as in four disease models: bleomycin-induced fibrosis, elastase-induced emphysema, LPS-induced acute lung injury and house dust mite-induced asthma. Results Respiratory mechanics parameters (airway resistance, tissue damping and tissue elastance) confirmed disease-specific phenotypes either at baseline or following methacholine challenge. Similarly, lung function defects could be detected in each disease model by at least one FE-related parameter (FEV0.1, FEF0.1, FVC, FEV0.1/FVC ratio and PEF) at baseline or during the methacholine provocation assay. Conclusions FE-derived outcomes in four mouse disease models behaved similarly to changes found in human spirometry. Routine combined lung function assessments could increase the translational utility of mouse models. Electronic supplementary material The online version of this article (doi:10.1186/s12931-017-0610-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Fien C Devos
- Center for Environment and Health, KU Leuven, Leuven, Belgium
| | - André Maaske
- Molecular and Medical Virology, Ruhr-University, Bochum, Germany
| | | | - Lore Pollaris
- Center for Environment and Health, KU Leuven, Leuven, Belgium
| | - Sven Seys
- Clinical Immunology, KU Leuven, Leuven, Belgium
| | | | - Erik Verbeken
- Translational Cell and Tissue Research, KU Leuven, Leuven, Belgium
| | - Matthias Tenbusch
- Molecular and Medical Virology, Ruhr-University, Bochum, Germany.,Institute of Clinical and Molecular Virology, University Hospital Erlangen, Erlangen-Nürnberg, Germany
| | - Rik Lories
- Skeletal Biology and Engineering Research Center, KU Leuven, Leuven, Belgium
| | - Benoit Nemery
- Center for Environment and Health, KU Leuven, Leuven, Belgium
| | - Peter Hm Hoet
- Center for Environment and Health, KU Leuven, Leuven, Belgium
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18
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19
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Park YA, Park HB, Kim YH, Sul IS, Yoon SH, Kim HR, Kim KW, Kim KE, Sohn MH. Airway hyperresponsiveness to mannitol and methacholine and exhaled nitric oxide in children with asthma. J Asthma 2017; 54:644-651. [PMID: 28055271 DOI: 10.1080/02770903.2016.1255751] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
OBJECTIVE Asthma is characterized by airway hyperresponsiveness (AHR), inflammation, and obstruction. AHR to stimuli that indirectly cause bronchial smooth muscle (BSM) contractions via release of endogenous mediators is thought to better reflect airway inflammation than AHR to stimuli that act directly on BSM. Fractional exhaled nitric oxide (FeNO) is a useful parameter for noninvasive clinical airway inflammation assessments. Accordingly, this study aimed to examine the relationships of mannitol and methacholine challenge test outcomes with FeNO and the influence of inhaled corticosteroid treatment in children with asthma. METHODS One hundred thirty-four asthmatic children (89 males; ages: 5-17 years, median: 9 years) underwent spirometry, FeNO measurement, serum total/specific IgE testing, and blood eosinophil count. All subjects were challenged with mannitol dry powder (MDP; AridolH, Pharmaxis, Australia) and methacholine at 7-day intervals. Data of steroid-treated and steroid-naïve children were compared. RESULTS Positive responses to MDP and methacholine challenge tests were observed in 74.6% and 67.2% of total subject group, respectively, and 72 children had positive response to both challenge tests. The median FeNO level, response-dose ratio (RDR) of PC20 methacholine, and RDR of PD15 MDP were significantly higher in the steroid-treated group than in the steroid-naïve group (p < 0.001, 0.226, and 0.004, respectively). FeNO levels associated significantly with PD15 MDP and RDR PD15 MDP in total subject populations (p = 0.016 and 0.003, respectively); however, a significant correlation between FeNO and RDR PD15 MDP was observed only in the steroid-naïve group. CONCLUSIONS Compared with AHR to methacholine, AHR to MDP more closely reflected the level of FeNO in steroid-naïve asthmatic children.
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Affiliation(s)
- Young A Park
- a Department of Pediatrics , Severance Children's Hospital , Seoul , Republic of Korea
| | - Hyun Bin Park
- a Department of Pediatrics , Severance Children's Hospital , Seoul , Republic of Korea
| | - Yoon Hee Kim
- b Gangnam Severance Hospital, Institute of Allergy, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine , Seoul , Republic of Korea
| | - In Sook Sul
- a Department of Pediatrics , Severance Children's Hospital , Seoul , Republic of Korea
| | - Seo Hee Yoon
- a Department of Pediatrics , Severance Children's Hospital , Seoul , Republic of Korea
| | - Hye Ran Kim
- a Department of Pediatrics , Severance Children's Hospital , Seoul , Republic of Korea
| | - Kyung Won Kim
- a Department of Pediatrics , Severance Children's Hospital , Seoul , Republic of Korea
| | - Kyu-Earn Kim
- b Gangnam Severance Hospital, Institute of Allergy, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine , Seoul , Republic of Korea
| | - Myung Hyun Sohn
- a Department of Pediatrics , Severance Children's Hospital , Seoul , Republic of Korea
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20
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Kotecha SJ, Watkins WJ, Lowe J, Henderson AJ, Kotecha S. Effect of early-term birth on respiratory symptoms and lung function in childhood and adolescence. Pediatr Pulmonol 2016; 51:1212-1221. [PMID: 27124554 DOI: 10.1002/ppul.23448] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Revised: 04/07/2016] [Accepted: 04/08/2016] [Indexed: 12/22/2022]
Abstract
BACKGROUND Early-term-born subjects, (37-38 weeks' gestation), form a large part of the population and have an increased risk of neonatal respiratory morbidity and childhood respiratory symptoms; there is a paucity of data on their later lung function. We sought to (1) compare lung function at 8-9 and 14-17 years in early-term-born children with full-term-born children (39-43 weeks' gestation); (2) assess the role of caesarean section delivery; and (3) compare respiratory symptoms and diagnosis of asthma. METHODS Caucasian, singleton, term births from the Avon Longitudinal Study of Parents and Children (n = 14,062) who had lung spirometry at 8-9 (n = 5,465) and/or 14-17 (n = 3,666) years were classified as early or full term. RESULTS At 8-9 years, standardized spirometry measures, although within the normal range, were lower in the early-term-born group, (n = 911), compared to full-term controls (n = 4,554). Delivery by caesarean section did not influence later spirometry, and the effect of early-term birth was not modified by delivery by caesarean section. At 14-17 years, the spirometry measures in the early-term group, (n = 602), were similar to the full-term group (3,064), and the rates of asthma and respiratory symptoms were also similar between the two gestation groups. CONCLUSIONS Early-term-born children had lower lung function values at 8-9 years compared to the full-term group, but were similar by 14-17 years of age. Delivery at early term should be avoided due to early and late morbidity. Pediatr Pulmonol. 2016;51:1212-1221. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Sarah J Kotecha
- Department of Child Health, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - William John Watkins
- Department of Child Health, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - John Lowe
- Department of Child Health, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - A John Henderson
- School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom
| | - Sailesh Kotecha
- Department of Child Health, School of Medicine, Cardiff University, Cardiff, United Kingdom.
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21
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Udesen PB, Westergaard CG, Porsbjerg C, Backer V. Stability of FeNO and airway hyperresponsiveness to mannitol in untreated asthmatics. J Asthma 2016; 54:530-536. [PMID: 27668981 DOI: 10.1080/02770903.2016.1238928] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
OBJECTIVE Airway hyperresponsiveness and airway inflammation are important hallmarks of asthma and are useful in asthma diagnosing, monitoring and treatment. The aim of the study was to assess whether two commonly used clinical tests, the mannitol challenge and Fraction of exhaled NO (FeNO), were stable clinical indicators over time in stable untreated asthmatics. METHODS 54 non-smoking, asthma patients not treated with steroids were enrolled in the study and assessed at baseline and a median of 6 months later. At baseline and follow-up, FeNO and airway hyperesponsiveness to mannitol were measured, and asthma control was assessed with the Asthma Control Questionnaire (ACQ). RESULTS A total of 41 subjects completed both visits. Mean (SD) FEV1% at baseline was 94.1% (17.7) and at re-examination 94.6% (19.7) (ns). The ACQ score was unchanged from baseline (Mean (SD): 0.90 (± 0.73)) to follow-up 0.90 (± 0.74) (ns), as was the FEV1% (94.1% (±17.1%) vs 94.6% (19.7%)(ns) indicating that patients were clinically stable during follow-up. The response to mannitol was unchanged at follow-up (Geometric mean (CI) of Response Dose Ratio (RDR) to mannitol: 0.026(0.013-0.046) vs 0.026(0.012-0.050) (ns). There was a slight decrease in FeNO at follow-up (25.5 ppb (19.7-32.9) to 21.9 ppb (17.1-28.2) (p < 0.001). CONCLUSIONS In steroid-free non-smoking asthmatics with constant symptom scores and lung function, airway responsiveness to mannitol remained at the same level over a period of months, while a minor change in exhaled FeNO was reported. These results suggest that mannitol is a stable, reliable marker of clinical disease activity.
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Affiliation(s)
| | | | - Celeste Porsbjerg
- a Respiratory Research Unit , Bispebjerg University Hospital , Copenhagen , Denmark
| | - Vibeke Backer
- a Respiratory Research Unit , Bispebjerg University Hospital , Copenhagen , Denmark
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Anderson JR, Mortimer K, Pang L, Smith KM, Bailey H, Hodgson DB, Shaw DE, Knox AJ, Harrison TW. Evaluation of the PPAR-γ Agonist Pioglitazone in Mild Asthma: A Double-Blind Randomized Controlled Trial. PLoS One 2016; 11:e0160257. [PMID: 27560168 PMCID: PMC4999189 DOI: 10.1371/journal.pone.0160257] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 07/15/2016] [Indexed: 11/18/2022] Open
Abstract
Background Peroxisome proliferator-activated receptor gamma (PPAR-γ) is a nuclear receptor that modulates inflammation in models of asthma. To determine whether pioglitazone improves measures of asthma control and airway inflammation, we performed a single-center randomized, double-blind, placebo-controlled, parallel-group trial. Methods Sixty-eight participants with mild asthma were randomized to 12 weeks pioglitazone (30 mg for 4 weeks, then 45 mg for 8 weeks) or placebo. The primary outcome was the adjusted mean forced expiratory volume in one second (FEV1) at 12 weeks. The secondary outcomes were mean peak expiratory flow (PEF), scores on the Juniper Asthma Control Questionnaire (ACQ) and Asthma Quality of Life Questionnaire (AQLQ), fractional exhaled nitric oxide (FeNO), bronchial hyperresponsiveness (PD20), induced sputum counts, and sputum supernatant interferon gamma-inducible protein-10 (IP-10), vascular endothelial growth factor (VEGF), monocyte chemotactic protein-1 (MCP-1), and eosinophil cationic protein (ECP) levels. Study recruitment was closed early after considering the European Medicines Agency’s reports of a potential increased risk of bladder cancer with pioglitazone treatment. Fifty-five cases were included in the full analysis (FA) and 52 in the per-protocol (PP) analysis. Results There was no difference in the adjusted FEV1 at 12 weeks (-0.014 L, 95% confidence interval [CI] -0.15 to 0.12, p = 0.84) or in any of the secondary outcomes in the FA. The PP analysis replicated the FA, with the exception of a lower evening PEF in the pioglitazone group (-21 L/min, 95% CI -39 to -4, p = 0.02). Conclusions We found no evidence that treatment with 12 weeks of pioglitazone improved asthma control or airway inflammation in mild asthma. Trial Registration ClinicalTrials.gov NCT01134835
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Affiliation(s)
- J. R. Anderson
- Nottingham Respiratory Research Unit, University of Nottingham, Clinical Sciences Building, City Hospital, Hucknall Road, Nottingham, NG5 1PB, United Kingdom
| | - K. Mortimer
- Liverpool School of Tropical Medicine, Liverpool, UK and Aintree University Hospital NHS Foundation Trust, Fazakerley, United Kingdom
- * E-mail:
| | - L. Pang
- Nottingham Respiratory Research Unit, University of Nottingham, Clinical Sciences Building, City Hospital, Hucknall Road, Nottingham, NG5 1PB, United Kingdom
| | - K. M Smith
- Nottingham Respiratory Research Unit, University of Nottingham, Clinical Sciences Building, City Hospital, Hucknall Road, Nottingham, NG5 1PB, United Kingdom
| | - H. Bailey
- Nottingham Respiratory Research Unit, University of Nottingham, Clinical Sciences Building, City Hospital, Hucknall Road, Nottingham, NG5 1PB, United Kingdom
| | - D. B. Hodgson
- Nottingham Respiratory Research Unit, University of Nottingham, Clinical Sciences Building, City Hospital, Hucknall Road, Nottingham, NG5 1PB, United Kingdom
| | - D. E. Shaw
- Nottingham Respiratory Research Unit, University of Nottingham, Clinical Sciences Building, City Hospital, Hucknall Road, Nottingham, NG5 1PB, United Kingdom
| | - A. J. Knox
- Nottingham Respiratory Research Unit, University of Nottingham, Clinical Sciences Building, City Hospital, Hucknall Road, Nottingham, NG5 1PB, United Kingdom
| | - T. W. Harrison
- Nottingham Respiratory Research Unit, University of Nottingham, Clinical Sciences Building, City Hospital, Hucknall Road, Nottingham, NG5 1PB, United Kingdom
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Porsbjerg C, Baines K, Gibson P, Bergqvist A, Erjefält JS, Sverrild A, Backer V. IL-33 is related to innate immune activation and sensitization to HDM in mild steroid-free asthma. Clin Exp Allergy 2016; 46:564-74. [DOI: 10.1111/cea.12702] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 11/24/2015] [Accepted: 12/18/2015] [Indexed: 01/03/2023]
Affiliation(s)
- C. Porsbjerg
- Respiratory Research Unit; Bispebjerg Hospital; Copenhagen Denmark
| | - K. Baines
- Centre for Asthma and Respiratory Disease; The University of Newcastle; Newcastle NSW Australia
| | - P. Gibson
- Centre for Asthma and Respiratory Disease; The University of Newcastle; Newcastle NSW Australia
| | - A. Bergqvist
- Respiratory Medicine and Allergology and Experimental Medical Science; Lund University; Lund Sweden
| | - J. S. Erjefält
- Respiratory Medicine and Allergology and Experimental Medical Science; Lund University; Lund Sweden
| | - A. Sverrild
- Respiratory Research Unit; Bispebjerg Hospital; Copenhagen Denmark
| | - V. Backer
- Respiratory Research Unit; Bispebjerg Hospital; Copenhagen Denmark
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Moeller A, Carlsen KH, Sly PD, Baraldi E, Piacentini G, Pavord I, Lex C, Saglani S. Monitoring asthma in childhood: lung function, bronchial responsiveness and inflammation. Eur Respir Rev 2016; 24:204-15. [PMID: 26028633 DOI: 10.1183/16000617.00003914] [Citation(s) in RCA: 78] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
This review focuses on the methods available for measuring reversible airways obstruction, bronchial hyperresponsiveness (BHR) and inflammation as hallmarks of asthma, and their role in monitoring children with asthma. Persistent bronchial obstruction may occur in asymptomatic children and is considered a risk factor for severe asthma episodes and is associated with poor asthma outcome. Annual measurement of forced expiratory volume in 1 s using office based spirometry is considered useful. Other lung function measurements including the assessment of BHR may be reserved for children with possible exercise limitations, poor symptom perception and those not responding to their current treatment or with atypical asthma symptoms, and performed on a higher specialty level. To date, for most methods of measuring lung function there are no proper randomised controlled or large longitudinal studies available to establish their role in asthma management in children. Noninvasive biomarkers for monitoring inflammation in children are available, for example the measurement of exhaled nitric oxide fraction, and the assessment of induced sputum cytology or inflammatory mediators in the exhaled breath condensate. However, their role and usefulness in routine clinical practice to monitor and guide therapy remains unclear, and therefore, their use should be reserved for selected cases.
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Affiliation(s)
- Alexander Moeller
- Division of Respiratory Medicine, University Children's Hospital Zurich, Zurich, Switzerland
| | - Kai-Hakon Carlsen
- Dept of Paediatrics, Women and Children's Division, University of Oslo and Oslo University Hospital, Oslo, Norway
| | - Peter D Sly
- Queensland Children's Medical Research Institute, The University of Queensland, Brisbane, Australia
| | - Eugenio Baraldi
- Women's and Children's Health Department, Unit of Respiratory Medicine and Allergy, University of Padova, Padova, Italy
| | - Giorgio Piacentini
- Paediatric Section, Dept of Life and Reproduction Sciences, University of Verona, Verona, Italy
| | - Ian Pavord
- Dept of Respiratory Medicine, University of Oxford, NDM Research Building, Oxford, UK
| | - Christiane Lex
- Dept of Paediatric Cardiology and Intensive Care Medicine, Division of Paediatric Respiratory Medicine, University Hospital Goettingen, Goettingen, Germany
| | - Sejal Saglani
- Leukocyte Biology and Respiratory Paediatrics, National Heart and Lung Institute, Imperial College London, London, UK
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Toennesen LL, Porsbjerg C, Pedersen L, Backer V. Predictors of airway hyperresponsiveness in elite athletes. Med Sci Sports Exerc 2016; 47:914-20. [PMID: 25202844 DOI: 10.1249/mss.0000000000000496] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
INTRODUCTION Elite athletes frequently experience asthma and airway hyperresponsiveness (AHR). We aimed to investigate predictors of airway pathophysiology in a group of unselected elite summer-sport athletes, training for the summer 2008 Olympic Games, including markers of airway inflammation, systemic inflammation, and training intensity. METHODS Fifty-seven Danish elite summer-sport athletes with and without asthma symptoms all gave a blood sample for measurements of high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor alpha (TNF-α), completed a respiratory questionnaire, and underwent spirometry. Bronchial challenges with mannitol were performed in all 57 athletes, and 47 agreed to perform an additional methacholine provocation. RESULTS Based on a physician's diagnosis, 18 (32%) athletes were concluded to be asthmatic. Asthmatic subjects trained more hours per week than the 39 nonasthmatics (median (min-max): 25 h·wk (14-30) versus 20 h·wk (11-30), P = 0.001). AHR to both methacholine and mannitol (dose response slope) increased with the number of weekly training h (r = 0.43, P = 0.003, and r = 0.28, P = 0.034, respectively). Serum levels of IL-6, IL-8, TNF-α, and hs-CRP were similar between asthmatics and nonasthmatics. However, there was a positive association between the degree of AHR to methacholine and serum levels of TNF-α (r = 0.36, P = 0.04). Fifteen out of 18 asthmatic athletes were challenged with both agents. In these subjects, no association was found between the levels of AHR to mannitol and methacholine (r = 0.032, P = 0.91). CONCLUSION AHR in elite athletes is related to the amount of weekly training and the level of serum TNF-α. No association was found between the level of AHR to mannitol and methacholine in the asthmatic athletes.
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Affiliation(s)
- Louise L Toennesen
- 1Department of Respiratory Medicine, Respiratory Research Unit, Bispebjerg Hospital, University of Copenhagen, DENMARK, and 2Department of Medicine, Roskilde Hospital, DENMARK
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Owens L, Laing I, Zhang G, Le Souef P. Early sensitization is associated with reduced lung function from birth into adulthood. J Allergy Clin Immunol 2015; 137:1605-1607.e2. [PMID: 26686471 DOI: 10.1016/j.jaci.2015.10.030] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 10/02/2015] [Accepted: 10/10/2015] [Indexed: 02/03/2023]
Affiliation(s)
- Louisa Owens
- School of Paediatrics and Child Health, University of Western Australia, Perth, Australia.
| | - Ingrid Laing
- School of Paediatrics and Child Health, University of Western Australia, Perth, Australia
| | - Guicheng Zhang
- School of Paediatrics and Child Health, University of Western Australia, Perth, Australia
| | - Peter Le Souef
- School of Paediatrics and Child Health, University of Western Australia, Perth, Australia
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Chapman DG, Irvin CG. Mechanisms of airway hyper-responsiveness in asthma: the past, present and yet to come. Clin Exp Allergy 2015; 45:706-19. [PMID: 25651937 DOI: 10.1111/cea.12506] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Airway hyper-responsiveness (AHR) has long been considered a cardinal feature of asthma. The development of the measurement of AHR 40 years ago initiated many important contributions to our understanding of asthma and other airway diseases. However, our understanding of AHR in asthma remains complicated by the multitude of potential underlying mechanisms which in reality are likely to have different contributions amongst individual patients. Therefore, the present review will discuss the current state of understanding of the major mechanisms proposed to contribute to AHR and highlight the way in which AHR testing is beginning to highlight distinct abnormalities associated with clinically relevant patient populations. In doing so we aim to provide a foundation by which future research can begin to ascribe certain mechanisms to specific patterns of bronchoconstriction and subsequently match phenotypes of bronchoconstriction with clinical phenotypes. We believe that this approach is not only within our grasp but will lead to improved mechanistic understanding of asthma phenotypes and we hoped to better inform the development of phenotype-targeted therapy.
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Affiliation(s)
- D G Chapman
- Woolcock Institute of Medical Research, Sydney Medical School, University of Sydney, Sydney, NSW, Australia; Department of Medicine, University of Vermont College of Medicine, Burlington, VT, USA
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Wang Q, Ji J, Xie Y, Guan W, Zhang Y, Wang Z, Wu K, Zhong N. Lower airway inflammation and hyperresponsiveness in non-asthmatic patients with non-allergic rhinitis. J Thorac Dis 2015; 7:1756-64. [PMID: 26623098 DOI: 10.3978/j.issn.2072-1439.2015.10.26] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND Potential associations between non-allergic rhinitis (NAR) and asthma have been verified epidemiologically, but these associations remain not very clear. It is necessary to further explore the possible implication of lower airway abnormities in NAR patients but without asthma. This study aims to determine lower airway hyperresponsiveness (AHR), inflammation and lung function in non-asthmatic patients with NAR. METHODS We recruited 262 non-asthmatic patients with NAR, 377 with AR and 264 healthy subjects. All subjects were non-smokers who underwent meticulous history taking, nasal examination, allergen skin prick test (SPT), blood routine test, measurement of fractional exhaled nitric oxide (FeNO), methacholine bronchial challenge test and induced sputum eosinophil count, in this order. RESULTS Compared with healthy subjects, non-asthmatic patients with NAR yielded markedly lower FEV1/FVC, maximal mid-expiratory flow (MMEF), mid-expiratory flow when 50% of FVC has been expired (MEF50%) and mid-expiratory flow when 75% of FVC has been expired (MEF25%) (P<0.05). Differences in spirometry between group AR and NAR were unremarkable (P>0.05). Patients with NAR yielded higher rate of AHR and higher FeNO levels than healthy subjects but lower than those with AR. The proportion of lower airways disorders (sputum eosinophilia, high FeNO levels or AHR) was highest in group AR (70.8%), followed by NAR (53.4%) and healthy subjects (24.2%) (P<0.01). However, sputum eosinophils in NAR patients were not higher compared with healthy subjects (P>0.05). Sputum eosinophils and FeNO had significant correlation with positive AHR and MMEF in group AR but not in NAR. CONCLUSIONS Non-asthmatic patients with NAR harbor lower AHR, small airways dysfunction and inflammation, despite being less significant than those with AR. This offers clues to unravel the link between NAR and asthma.
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Affiliation(s)
- Qiuping Wang
- 1 Department of Otolaryngology and Head Neck Surgery, Jinling Hospital, Nanjing 210002, China ; 2 State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China
| | - Junfeng Ji
- 1 Department of Otolaryngology and Head Neck Surgery, Jinling Hospital, Nanjing 210002, China ; 2 State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China
| | - Yanqing Xie
- 1 Department of Otolaryngology and Head Neck Surgery, Jinling Hospital, Nanjing 210002, China ; 2 State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China
| | - Weijie Guan
- 1 Department of Otolaryngology and Head Neck Surgery, Jinling Hospital, Nanjing 210002, China ; 2 State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China
| | - Yong Zhang
- 1 Department of Otolaryngology and Head Neck Surgery, Jinling Hospital, Nanjing 210002, China ; 2 State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China
| | - Zhiyi Wang
- 1 Department of Otolaryngology and Head Neck Surgery, Jinling Hospital, Nanjing 210002, China ; 2 State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China
| | - Kunmin Wu
- 1 Department of Otolaryngology and Head Neck Surgery, Jinling Hospital, Nanjing 210002, China ; 2 State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China
| | - Nanshan Zhong
- 1 Department of Otolaryngology and Head Neck Surgery, Jinling Hospital, Nanjing 210002, China ; 2 State Key Laboratory of Respiratory Disease, National Clinical Research Center for Respiratory Disease, Guangzhou Institute of Respiratory Disease, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou 510120, China
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Galobardes B, Granell R, Sterne J, Hughes R, Mejia-Lancheros C, Davey Smith G, Henderson J. Childhood wheezing, asthma, allergy, atopy, and lung function: different socioeconomic patterns for different phenotypes. Am J Epidemiol 2015; 182:763-74. [PMID: 26443417 PMCID: PMC4617295 DOI: 10.1093/aje/kwv045] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 02/10/2015] [Indexed: 11/13/2022] Open
Abstract
Identifying preventable exposures that lead to asthma and associated allergies has proved challenging, partly because of the difficulty in differentiating phenotypes that define homogeneous disease groups. Understanding the socioeconomic patterns of disease phenotypes can help distinguish which exposures are preventable. In the present study, we identified disease phenotypes that are susceptible to socioeconomic variation, and we determined which life-course exposures were associated with these inequalities in a contemporary birth cohort. Participants included children from the Avon Longitudinal Study of Parents and Children, a population-based birth cohort in England, who were born in 1991 and 1992 and attended the clinic at 7–8 years of age (n = 6,378). Disease phenotypes included asthma, atopy, wheezing, altered lung function, and bronchial reactivity phenotypes. Combining atopy with a diagnosis of asthma from a doctor captured the greatest socioeconomic variation, including opposing patterns between phenotype groups: Children with a low socioeconomic position (SEP) had more asthma alone (adjusted multinomial odds ratio = 1.50, 95% confidence interval: 1.21, 1.87) but less atopy alone (adjusted multinomial odds ratio = 0.80, 95% confidence interval: 0.66, 0.98) than did children with high SEP. Adjustment for maternal exposure to tobacco smoke during pregnancy and childhood exposure to tobacco smoke reduced the odds of asthma alone in children with a low SEP. Current inequalities among children who have asthma but not atopy can be prevented by eliminating exposure to tobacco smoke. Other disease phenotypes were not socially patterned or had SEP patterns that were not related to smoke exposure.
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Affiliation(s)
- Bruna Galobardes
- Correspondence to Dr. Bruna Galobardes, University of Bristol, School of Social and Community Medicine, Oakfield House, Oakfield Grove, BS8 2BN, United Kingdom (e-mail: )
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Cox DW, Mullane D, Zhang GC, Turner SW, Hayden CM, Goldblatt J, Landau LI, Le Souëf PN. Longitudinal assessment of airway responsiveness from 1 month to 18 years in the PIAF birth cohort. Eur Respir J 2015; 46:1654-61. [PMID: 26493795 DOI: 10.1183/13993003.00397-2015] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 06/25/2015] [Indexed: 01/29/2023]
Abstract
The Perth Infant Asthma Follow-up (PIAF) study involves a birth cohort of unselected subjects who have undergone longitudinal assessments of airway responsiveness at 1, 6 and 12 months and 6, 11 and 18 years of age. The aim of this study was to determine the relationship between increased airway responsiveness throughout childhood and asthma in early adult life.Airway responsiveness to histamine, assessed as a dose-response slope (DRS), and a respiratory questionnaire were completed at 1, 6 and 12 months and 6, 11 and 18 years of age.253 children were initially recruited and studied. Airway responsiveness was assessed in 203, 174, 147, 103, 176 and 137 children at the above-mentioned time points, respectively (39 participants being assessed on all test occasions). Asthma at 18 years was associated with increased airway responsiveness at 6, 12 and 18 years, but not during infancy (slope 0.24, 95% CI 0.06-0.42; p=0.01; slope 0.25, 95% CI 0.08-0.49; p=0.006; and slope 0.56, 95% CI 0.29-0.83; p<0.001, respectively).Increased airway responsiveness and its association with asthma at age 18 years is established between infancy and 6 years. We propose that airway responsiveness in early life reflects the initial airway geometry and airway responsiveness later in childhood increasingly reflects immunological responses to environmental influences.
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Affiliation(s)
- Desmond W Cox
- School of Paediatrics and Child Health, University of Western Australia, Perth, Australia Our Lady's Children's Hospital, Crumlin, Dublin, Ireland
| | - Dave Mullane
- School of Paediatrics and Child Health, University of Western Australia, Perth, Australia
| | - Guicheng C Zhang
- School of Paediatrics and Child Health, University of Western Australia, Perth, Australia School of Public Health, Curtin University, Perth, Australia
| | - Steve W Turner
- School of Paediatrics and Child Health, University of Western Australia, Perth, Australia
| | - Catherine M Hayden
- School of Paediatrics and Child Health, University of Western Australia, Perth, Australia
| | - Jack Goldblatt
- School of Paediatrics and Child Health, University of Western Australia, Perth, Australia King Edward Memorial Hospital, Perth, Australia
| | - Lou I Landau
- School of Paediatrics and Child Health, University of Western Australia, Perth, Australia
| | - Peter N Le Souëf
- School of Paediatrics and Child Health, University of Western Australia, Perth, Australia Respiratory Medicine, Princess Margaret Hospital, Perth, Australia
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Bolund ACS, Miller MR, Basinas I, Elholm G, Omland Ø, Sigsgaard T, Schlünssen V. The effect of occupational farming on lung function development in young adults: a 15-year follow-up study. Occup Environ Med 2015; 72:707-13. [PMID: 26265668 DOI: 10.1136/oemed-2014-102726] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 05/29/2015] [Indexed: 12/24/2022]
Abstract
OBJECTIVES Longitudinal studies on the effect of farming on lung function in young participants are few. Our objective was to explore if exposure to farming impaired lung function in young adults. METHODS We studied 1964 farming students and 407 controls in 1992/2004, and carried out follow-up in 2007/2008. Spirometry, skin prick test and bronchial hyper-responsiveness (BHR) were assessed, height and weight measured, and questionnaires covering health and occupation were collected. Cumulative dust and endotoxin exposures were estimated from modelled personal dust measurements. Lung function effect was expressed as change in z-score during follow-up using the Global Lung Initiative 2012 project prediction equations. Longitudinal data were available for 1134 young participants ≤25 years at baseline. RESULTS We found no differences in lung function Δz-scores between farmers and controls, however, adjusted multivariable linear regression showed a negative effect among current farmers on ΔzFEV1 (forced expiratory volume in 1 s; -0.12, p=0.006) and ΔzFEV1/FVC (forced vital capacity; -0.15, p=0.009) compared to ex-farmers. An interaction was found between sex and farming, showing that current farming suppresses ΔzFEV1 and ΔzFVC more among females. Smoking in farmers had a deleterious effect on ΔzFEV1, which was not seen in controls, though no significant interaction was found. Farm upbringing protected against impairment of lung function, and BHR at baseline had a deleterious effect on ΔzFEV1 only in those not raised on a farm. CONCLUSIONS We conclude that being a current farmer is associated with a negative effect on lung function, when compared to ex-farmers, with females being more susceptible. Being raised on a farm protects against the adverse effect of BHR on change in lung function.
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Affiliation(s)
- Anneli C S Bolund
- Department of Public Health, Section of Environment Occupation and Health, Danish Ramazzini Centre, University of Aarhus, Aarhus C, Denmark
| | - Martin R Miller
- Institute of Occupational and Environmental Medicine, University of Birmingham, Birmingham, West Midlands, UK
| | - Ioannis Basinas
- Department of Public Health, Section of Environment Occupation and Health, Danish Ramazzini Centre, University of Aarhus, Aarhus C, Denmark
| | - Grethe Elholm
- Department of Public Health, Section of Environment Occupation and Health, Danish Ramazzini Centre, University of Aarhus, Aarhus C, Denmark
| | - Øyvind Omland
- Department of Occupational Medicine, Danish Ramazzini Centre, Aalborg University Hospital, Aalborg, Denmark
| | - Torben Sigsgaard
- Department of Public Health, Section of Environment Occupation and Health, Danish Ramazzini Centre, University of Aarhus, Aarhus C, Denmark
| | - Vivi Schlünssen
- Department of Public Health, Section of Environment Occupation and Health, Danish Ramazzini Centre, University of Aarhus, Aarhus C, Denmark
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Westergaard CG, Porsbjerg C, Backer V. The effect of Varenicline on smoking cessation in a group of young asthma patients. Respir Med 2015; 109:1416-22. [PMID: 26427627 DOI: 10.1016/j.rmed.2015.07.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 07/20/2015] [Accepted: 07/27/2015] [Indexed: 10/23/2022]
Abstract
BACKGROUND Tobacco use causes long-term morbidity and mortality. In patients with asthma, the frequency of smokers is high; however, asthmatic smokers experience more pronounced symptoms, accelerated loss of lung function and treatment resistance. Varenicline is an effective drug in smoking cessation, when investigated in COPD patients and general populations. The aim of the present study was to evaluate the effect of Varenicline on tobacco cessation in young asthmatics. METHODS In a randomized, placebo-controlled, double-blinded trial, 52 asthmatic current smokers (age 19-40) ≥ 10 cigarettes daily and ≥10 packyears (mean 15.6) were recruited to a 12 week treatment period with Varenicline or placebo (1:1) in parallel design. Evaluation of smoking status, asthma symptom score, general health quality score and methacholine challenge were performed at week 0, week 6, week 12 and week 24. RESULTS In the Varenicline group, at week 12, 69% of the patients quit smoking vs. 36% in the placebo group (p = 0.017, intended-to-treat analysis), but after 24 weeks, a high relapse rate was present (quit rates 19% vs. 16%, NS). After 6 weeks of treatment, significant improvements in airway hyperresponsiveness (AHR) in the Varenicline group was found (from 88% to 58%, p = 0.016), whereas no change was observed in the placebo group. Symptom score and general health quality improved in both the Varenicline and the placebo group. CONCLUSION We demonstrated that Varenicline can be used with a high probability of success with tobacco cessation in young smokers with asthma, but relapse rate after end of treatment is high. Quitting smoking can improve asthma control.
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Affiliation(s)
| | - Celeste Porsbjerg
- Respiratory Research Unit, Bispebjerg University Hospital, Copenhagen, Denmark
| | - Vibeke Backer
- Respiratory Research Unit, Bispebjerg University Hospital, Copenhagen, Denmark
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Elmose C, Sverrild A, van der Sluis S, Kyvik KO, Backer V, Thomsen SF. Genetic factors explain half of all variance in serum eosinophil cationic protein. Clin Exp Allergy 2015; 44:1525-30. [PMID: 25354326 DOI: 10.1111/cea.12445] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 09/15/2014] [Accepted: 09/22/2014] [Indexed: 11/30/2022]
Abstract
BACKGROUND Eosinophil cationic protein (ECP) is one of four basic proteins of the secretory granules of eosinophils. It has a variety of functions associated with inflammatory responses. Little is known about the causes for variation in serum ECP levels. AIM To identify factors associated with variation in serum ECP and to determine the relative proportion of the variation in ECP due to genetic and non-genetic factors, in an adult twin sample. METHODS A sample of 575 twins, selected through a proband with self-reported asthma, had serum ECP, lung function, airway responsiveness to methacholine, exhaled nitric oxide, and skin test reactivity, measured. Linear regression analysis and variance component models were used to study factors associated with variation in ECP and the relative genetic influence on ECP levels. RESULTS Sex (regression coefficient = -0.107, P < 0.001), body mass index (BMI) (0.007, P = 0.028), and airway responsiveness to methacholine (0.074, P = 0.001) were significantly associated with ECP. Adjusted for these factors, ECP correlated 0.53 (P < 0.001) and 0.27 (P = 0.001) in monozygotic and dizygotic twins, respectively (P-value for difference = 0.05). According to the most parsimonious variance component model, genetic factors accounted for 57% (CI: 42-72%, P < 0.001) of the variance in ECP levels, whereas the remainder (43%) was ascribable to non-shared environmental factors. The genetic correlation between ECP and airway responsiveness to methacholine was statistically non-significant (r = -0.11, P = 0.50). CONCLUSION Around half of all variance in serum ECP is explained by genetic factors. Serum ECP is influenced by sex, BMI, and airway responsiveness. Serum ECP and airway responsiveness seem not to share genetic variance.
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Affiliation(s)
- C Elmose
- Department of Dermato-allergology, Gentofte Hospital, Hellerup, Denmark
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Bildstrup L, Backer V, Thomsen SF. Increased body mass index predicts severity of asthma symptoms but not objective asthma traits in a large sample of asthmatics. J Asthma 2015; 52:687-92. [PMID: 25582044 DOI: 10.3109/02770903.2015.1005840] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AIM To examine the relationship between body mass index (BMI) and different indicators of asthma severity in a large community-based sample of Danish adolescents and adults. METHODS A total of 1186 subjects, 14-44 years of age, who in a screening questionnaire had reported a history of airway symptoms suggestive of asthma and/or allergy, or who were taking any medication for these conditions were clinically examined. All participants were interviewed about respiratory symptoms and furthermore height and weight, skin test reactivity, lung function, and airway responsiveness were measured. RESULTS A total of 516 individuals had asthma. The mean BMI was 24.9 kg/m(2) (SD = 5.1). Asthma severity measured by GINA score increased with increasing BMI (p = 0.009). The result remained significant after adjusting for age, sex, medication use for asthma and smoking (p = 0.010). Severity of individual asthma symptoms; cough (p = 0.002) and chest tightness (p = 0.023) was also significantly related to BMI, whereas severity of wheezing and shortness of breath was not. Airway obstruction was more pronounced in subjects with increased BMI (p < 0.001) but the effect disappeared after adjustment for covariates (p = 0.233). Lung function, airway responsiveness, and atopy were not significantly related to BMI as were use of medication for asthma and adherence to treatment. CONCLUSIONS In adults, increased body mass index predicts severity of asthma symptoms but not objective asthma traits.
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Affiliation(s)
- Line Bildstrup
- a Department of Respiratory Medicine , Bispebjerg Hospital , Copenhagen , Denmark
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Sonnenschein-van der Voort AMM, Howe LD, Granell R, Duijts L, Sterne JAC, Tilling K, Henderson AJ. Influence of childhood growth on asthma and lung function in adolescence. J Allergy Clin Immunol 2015; 135:1435-43.e7. [PMID: 25577593 PMCID: PMC4452091 DOI: 10.1016/j.jaci.2014.10.046] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2013] [Revised: 10/03/2014] [Accepted: 10/16/2014] [Indexed: 11/30/2022]
Abstract
Background Low birth weight and rapid infant growth in early infancy are associated with increased risk of childhood asthma, but little is known about the role of postinfancy growth in asthmatic children. Objectives We sought to examine the associations of children's growth patterns with asthma, bronchial responsiveness, and lung function until adolescence. Methods Individual growth trajectories from birth until 10 years of age were estimated by using linear spline multilevel models for 9723 children participating in a population-based prospective cohort study. Current asthma at 8, 14, and 17 years of age was based on questionnaires. Lung function and bronchial responsiveness or reversibility were measured during clinic visits at 8 and 15 years of age. Results Rapid weight growth between 0 and 3 months of age was most consistently associated with increased risks of current asthma at the ages of 8 and 17 years, bronchial responsiveness at age 8 years, and bronchial reversibility at age 15 years. Rapid weight growth was associated with lung function values, with the strongest associations for weight gain between 3 and 7 years of age and higher forced vital capacity (FVC) and FEV1 values at age 15 years (0.12 [95% CI, 0.08 to 0.17] and 0.11 [95% CI, 0.07 to 0.15], z score per SD, respectively) and weight growth between 0 and 3 months of age and lower FEV1/FVC ratios at age 8 and 15 years (−0.13 [95% CI, −0.16 to −0.10] and −0.04 [95% CI, −0.07 to −0.01], z score per SD, respectively). Rapid length growth was associated with lower FVC and FVC1 values at age 15 years. Conclusion Faster weight growth in early childhood is associated with asthma and bronchial hyperresponsiveness, and faster weight growth across childhood is associated with higher FVC and FEV1 values.
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Affiliation(s)
- Agnes M M Sonnenschein-van der Voort
- School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom; Department of Pediatrics, Division of Respiratory Medicine, Erasmus Medical Center, Rotterdam, The Netherlands; Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Laura D Howe
- School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom; Medical Research Council Integrative Epidemiology Unit, University of Bristol, Bristol, United Kingdom
| | - Raquel Granell
- School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom
| | - Liesbeth Duijts
- Department of Pediatrics, Division of Respiratory Medicine, Erasmus Medical Center, Rotterdam, The Netherlands; Department of Epidemiology, Erasmus Medical Center, Rotterdam, The Netherlands; Department of Pediatrics, Division of Neonatology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Jonathan A C Sterne
- School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom
| | - Kate Tilling
- School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom
| | - A John Henderson
- School of Social and Community Medicine, University of Bristol, Bristol, United Kingdom.
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Collin S, Granell R, Westgarth C, Murray J, Paul E, Sterne J, Henderson AJ. Pet ownership is associated with increased risk of non-atopic asthma and reduced risk of atopy in childhood: findings from a UK birth cohort. Clin Exp Allergy 2015; 45:200-10. [PMID: 25077415 PMCID: PMC4280336 DOI: 10.1111/cea.12380] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2013] [Revised: 05/25/2014] [Accepted: 05/31/2014] [Indexed: 12/19/2022]
Abstract
BACKGROUND Studies have shown an inverse association of pet ownership with allergy but inconclusive findings for asthma. OBJECTIVE To investigate whether pet ownership during pregnancy and childhood was associated with asthma and atopy at the age of 7 in a UK population-based birth cohort. METHODS Data from the Avon Longitudinal Study of Parents and Children (ALSPAC) were used to investigate associations of pet ownership at six time points from pregnancy to the age of 7 with asthma, atopy (grass, house dust mite, and cat skin prick test) and atopic vs. non-atopic asthma at the age of 7 using logistic regression models adjusted for child's sex, maternal history of asthma/atopy, maternal smoking during pregnancy, and family adversity. RESULTS A total of 3768 children had complete data on pet ownership, asthma, and atopy. Compared with non-ownership, continuous ownership of any pet (before and after the age of 3) was associated with 52% lower odds of atopic asthma [odds ratio (OR) 0.48, 95% CI 0.34-0.68]. Pet ownership tended to be associated with increased risk of non-atopic asthma, particularly rabbits (OR 1.61, 1.04-2.51) and rodents (OR 1.86, 1.15-3.01), comparing continuous vs. non-ownership. Pet ownership was consistently associated with lower odds of sensitization to grass, house dust mite, and cat allergens, but rodent ownership was associated with higher odds of sensitization to rodent allergen. Differential effects of pet ownership on atopic vs. non-atopic asthma were evident for all pet types. CONCLUSIONS AND CLINICAL RELEVANCE Pet ownership during pregnancy and childhood in this birth cohort was consistently associated with a reduced risk of aeroallergen sensitization and atopic asthma at the age of 7, but tended to be associated (particularly for rabbits and rodents) with an increased risk of non-atopic asthma. The opposing effects on atopy vs. non-atopic asthma might be considered by parents when they are deciding whether to acquire a pet.
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Affiliation(s)
- S.M. Collin
- School of Social & Community Medicine, University of Bristol, UK
| | - R Granell
- School of Social & Community Medicine, University of Bristol, UK
| | - C Westgarth
- Institute of Infection and Global Health, University of Liverpool, UK
| | - J Murray
- School of Veterinary Science, University of Bristol, UK
| | - E Paul
- School of Veterinary Science, University of Bristol, UK
| | - J.A.C. Sterne
- School of Social & Community Medicine, University of Bristol, UK
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Miller LL, Henderson J, Northstone K, Pembrey M, Golding J. Do grandmaternal smoking patterns influence the etiology of childhood asthma? Chest 2014; 145:1213-1218. [PMID: 24158349 PMCID: PMC4042509 DOI: 10.1378/chest.13-1371] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Background: Animal data suggest that tobacco smoke exposure of a mother when she is in utero influences DNA methylation patterns in her offspring and that there is an effect on the respiratory system, particularly airway responsiveness. The only study, to our knowledge, in humans suggests that there is a similar effect on asthma. The present study tests whether an association with respiratory problems can be confirmed in a large population study and aims to determine whether in utero exposure of the father has similar effects on his offspring. Methods: Information from the Avon Longitudinal Study of Parents and Children was used to compare the offspring of women and of men who had themselves been exposed to cigarette smoke in utero; separate analyses were performed for children of women smokers and nonsmokers. The outcome measures were trajectories of history of early wheezing, doctor-diagnosed asthma by age 7 years, and results of lung function and methacholine challenge tests at 8 years. A variety of social and environmental factors were taken into account; offspring sexes were examined separately. Results: There was no association with any outcome in relation to maternal prenatal exposure. There was some evidence of an increase in asthma risk with paternal prenatal exposure when the study mother was a nonsmoker (adjusted OR, 1.17; 95% CI, 0.97-1.41). This was particularly strong for girls (adjusted OR, 1.39; 95% CI, 1.04-1.86). Conclusions: We did not find that maternal prenatal exposure to her mother’s smoking had any effect on her children’s respiratory outcomes. There was suggestive evidence of paternal prenatal exposure being associated with asthma and persistent wheezing in the granddaughters.
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Affiliation(s)
- Laura L Miller
- School of Social and Community Medicine, University of Bristol, Bristol, England
| | - John Henderson
- School of Social and Community Medicine, University of Bristol, Bristol, England
| | - Kate Northstone
- School of Social and Community Medicine, University of Bristol, Bristol, England
| | - Marcus Pembrey
- School of Social and Community Medicine, University of Bristol, Bristol, England
| | - Jean Golding
- School of Social and Community Medicine, University of Bristol, Bristol, England.
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Westergaard CG, Porsbjerg C, Backer V. The effect of smoking cessation on airway inflammation in young asthma patients. Clin Exp Allergy 2014; 44:353-61. [PMID: 24286379 DOI: 10.1111/cea.12243] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2013] [Revised: 11/19/2013] [Accepted: 11/25/2013] [Indexed: 12/01/2022]
Abstract
BACKGROUND Smoking has been shown to have several detrimental effects on asthma, including poor symptom control, attenuated treatment response and accelerated decline in lung function. In spite of this, smoking is at least as common among asthma patients as in the rest of the population. The aggravations of smoking on asthma may be caused by effects on airway inflammation, which has been found to be changed in asthmatic smokers. It is not known whether these smoking-induced airway inflammation changes are reversible after smoking cessation. OBJECTIVE The aim of this study was to assess airway changes in asthmatic smokers before and during smoking cessation. METHODS Forty-six smokers with asthma, all steroid-free (age range: 19-40), were recruited. All participants attempted smoking cessation over a period of 3 months. Visits were performed at weeks 0, 6 and 12 and included induced sputum, FeNO, methacholine challenge, lung function, Asthma Control Questionnaire (ACQ6) and exhaled CO. RESULTS Twenty-six of 46 patients succeeded in quitting smoking. In the quitters, improvements in methacholine AHR (77% before and 52% after smoking cessation, respectively, P = 0.016) and ACQ6 score (1.7-0.7, P = 0.034) and FeNO (8.7-14.8 p.p.b., P = 0.002) were observed, whereas no significant changes were found regarding eosinophils or lung function. A small but significant decrease in neutrophils (54.1-52%, P = 0.003) was present in quitters compared with the non-quitters. Non-quitters experienced no changes in any parameters. CONCLUSION Smoking cessation improved asthma control, but the changes were not related to change in eosinophilic inflammation, and the reduction in neutrophils was small. Thus, airway inflammation with eosinophils and neutrophils may be less important drivers of asthma control in smokers than other factors. CLINICAL RELEVANCE Smoking cessation may improve clinically important disease parameters such as AHR and symptom score, but likely unrelated to changes in airway inflammation.
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Affiliation(s)
- C G Westergaard
- Respiratory Research Unit, Bispebjerg University Hospital, Copenhagen, Denmark
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Gade EJ, Thomsen SF, Lindenberg S, Macklon NS, Backer V. Lower values of VEGF in endometrial secretion are a possible cause of subfertility in non-atopic asthmatic patients. J Asthma 2014; 52:336-42. [PMID: 25243322 DOI: 10.3109/02770903.2014.966915] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
OBJECTIVE Using endometrial secretion analysis, we assessed whether altered inflammatory cytokine levels can be detected in the uterine environment in asthma patients, thereby providing a possible cause of reduced fertility in asthmatics. METHODS Forty-four unexplained infertile women (aged 28-44) underwent asthma and allergy testing, questionnaires, endometrial secretion and blood samples in the mid-secretory phase of the menstrual cycle (day 19-23) during assisted reproduction. Differences in cytokines and growth factors were analyzed. RESULTS Mean log-VEGF in uteri was lower in asthma patients compared with controls (2.29 versus 2.70, p = 0.028). This was mainly due to lower values of VEGF among women with non-atopic asthma compared with women with atopic asthma (1.86 versus 2.72, p = 0.009) and with healthy controls (1.86 versus 2.70, p = 0.01). Asthma treatment status had no effect on VEGF levels in uteri. Serum high sensitivity CRP was negatively correlated with VEGF in endometrial secretions. No other significant correlations were observed between peripheral blood values and markers found in utero. CONCLUSION Asthma is associated with lower values of VEGF in uterine endometrial secretions, which might affect the receptiveness of the endometrium and thereby increase time to pregnancy. The effect appears to be associated with non-atopic asthma with general increased systemic inflammation.
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Affiliation(s)
- Elisabeth Juul Gade
- Respiratory Research Unit, Department of respiratory medicine, Bispebjerg University Hospital , Bispebjerg Bakke, Copenhagen , Denmark
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Abstract
This thesis explores the contribution of twin studies, particularly those studies originating from the Danish Twin Registry, to the understanding of the aetiology of asthma. First, it is explored how twin studies have established the contribution of genetic and environmental factors to the variation in the susceptibility to asthma, and to the variation in several aspects of the clinical expression of the disease such as its age at onset, its symptomatology, its intermediate phenotypes, and its relationship with other atopic diseases. Next, it is explored how twin studies have corroborated theories explaining asthma's recent increase in prevalence, and last, how these fit with the explanations of the epidemiological trends in other common chronic diseases of modernity.
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Porsbjerg C, Sverrild A, Stensen L, Backer V. The level of specialist assessment of adult asthma is influenced by patient age. Respir Med 2014; 108:1453-9. [PMID: 25087903 DOI: 10.1016/j.rmed.2014.07.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/11/2014] [Revised: 07/02/2014] [Accepted: 07/07/2014] [Indexed: 01/03/2023]
Abstract
BACKGROUND Late onset asthma is associated with more severe disease and higher morbidity than in younger asthma patients. This may in part relate to under recognition of asthma in older adults, but evidence on the impact of patient age on diagnostic assessment of asthma in a specialist setting is sparse. AIM To examine the impact of patient age on the type and proportion of diagnostic tests performed in patients undergoing specialist assessment for asthma. METHODS Data from a clinical population consisting of all patients consecutively referred over a 12 months period to a specialist clinic for assessment of asthma were analysed. RESULTS A total of 224 patients with asthma or suspected asthma were referred during the 12 month period; 86 adults aged <35 years, 95 aged 35-55 years and 43 aged >55 years. Symptom characteristics were similar, but adults >35 years had a lower lung function than younger adults, and were more frequently smokers. However, a regression analysis showed that older age was associated with a lower likelihood of diagnostic assessment with a reversibility test, a bronchial challenge test, or measurement of exhaled NO, independently of a known diagnosis of asthma, smoking habits and lung function at referral. CONCLUSION A lower level of diagnostic assessment was observed already after the age of 35 years, indicating a risk for under diagnosis of asthma at an earlier patient age than previously thought.
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Affiliation(s)
- C Porsbjerg
- Respiratosry Research Unit, Department of Respiratory Medicine, Bispebjerg University Hospital, Copenhagen, Denmark.
| | - A Sverrild
- Respiratosry Research Unit, Department of Respiratory Medicine, Bispebjerg University Hospital, Copenhagen, Denmark
| | - L Stensen
- Respiratosry Research Unit, Department of Respiratory Medicine, Bispebjerg University Hospital, Copenhagen, Denmark
| | - V Backer
- Respiratosry Research Unit, Department of Respiratory Medicine, Bispebjerg University Hospital, Copenhagen, Denmark
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Nielsen EW, Hull JH, Backer V. High prevalence of exercise-induced laryngeal obstruction in athletes. Med Sci Sports Exerc 2014; 45:2030-5. [PMID: 23657163 DOI: 10.1249/mss.0b013e318298b19a] [Citation(s) in RCA: 121] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
INTRODUCTION Unexplained respiratory symptoms reported by athletes are often incorrectly considered secondary to exercise-induced asthma. We hypothesized that this may be related to exercise-induced laryngeal obstruction (EILO). This study evaluates the prevalence of EILO in an unselected cohort of athletes. METHODS We retrospectively reviewed the prevalence of EILO in a cohort of athletes (n = 91) referred consecutively during a 2-yr period for asthma workup including continuous laryngoscopy during exercise (CLE) testing. We compared clinical characteristics and bronchial hyperreactivity between athletes with and without EILO. RESULTS Of 88 athletes who completed a full workup, 31 (35.2%) had EILO and 38 (43.2%) had a positive bronchoprovocation or bronchodilator reversibility test. The presence of inspiratory symptoms did not differentiate athletes with and without EILO. Sixty-one percent of athletes with EILO and negative bronchoprovocation and bronchodilator reversibility tests used regular asthma medication at referral. CONCLUSIONS In athletes with unexplained respiratory symptoms, EILO is an important differential diagnosis not discerned from other etiologies by clinical features. These findings have important implications for the assessment and management of athletes presenting with persistent respiratory symptoms despite asthma therapy.
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Affiliation(s)
- Emil Walsted Nielsen
- 1Respiratory Research Unit, Department of Respiratory Medicine, Copenhagen University Hospital Bispebjerg, Copenhagen, DENMARK; and 2Department of Respiratory Medicine, Royal Brompton Hospital, London, England, UNITED KINGDOM
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Wills AK, Shaheen SO, Granell R, Henderson AJ, Fraser WD, Lawlor DA. Maternal 25-hydroxyvitamin D and its association with childhood atopic outcomes and lung function. Clin Exp Allergy 2014; 43:1180-8. [PMID: 24074336 PMCID: PMC3814422 DOI: 10.1111/cea.12172] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Revised: 06/29/2013] [Accepted: 07/01/2013] [Indexed: 12/22/2022]
Abstract
Background It has been suggested that maternal vitamin D status in pregnancy influences the risk of asthma and atopy in the offspring. The epidemiological evidence to support these claims is conflicting and may reflect chance findings and differences in how vitamin D was assessed. Objective To examine the association between blood total maternal 25-hydroxy vitamin D (25(OH)D) concentrations in pregnancy and offspring asthma, atopy and lung function in the largest birth cohort study to date. Methods Participants were largely of white European origin and resident in the South West of England. We examined the associations of maternal 25(OH)D concentrations in pregnancy with the following outcomes in the offspring: wheeze, asthma, atopy, eczema, hayfever, at mean age 7.5 years (n = 3652–4696 depending on outcome), IgE at 7 years (n = 2915) and lung function and bronchial responsiveness at mean age 8.7 years (n = 3728–3784). Results Sixty-eight per cent of mothers had sufficient (> 50 nmol/L) concentrations of 25(OH)D, 27% were insufficient (27.5–49.99 nmol/L) and 5% were deficient (< 27.5 nmol/L). There was no evidence to suggest that maternal 25(OH)D concentration in pregnancy was associated with any respiratory or atopic outcome in the offspring. These findings remained after adjustment for season of measurement and for potential confounders. There was also no evidence that these relationships followed a non-linear form and no evidence that either deficient or high concentrations of maternal 25(OH)D were associated with atopic or respiratory outcomes. Conclusions We found no evidence that maternal blood 25(OH)D concentration in pregnancy is associated with childhood atopic or respiratory outcomes.
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Affiliation(s)
- A K Wills
- MRC Centre for Causal Analyses in Translational Epidemiology, University of Bristol, Bristol, UK; School of Social and Community Medicine, University of Bristol, Bristol, UK
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Cornish RP, Henderson J, Boyd AW, Granell R, Van Staa T, Macleod J. Validating childhood asthma in an epidemiological study using linked electronic patient records. BMJ Open 2014; 4:e005345. [PMID: 24760357 PMCID: PMC4010849 DOI: 10.1136/bmjopen-2014-005345] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
OBJECTIVE To investigate the performance of parent-reported data in identifying physician-confirmed asthma. DESIGN AND SETTING Validation study using linkage between the Avon Longitudinal Study of Parents and Children (ALSPAC) and electronic patient records held within the General Practice Research Database (GPRD). PARTICIPANTS Participants were those eligible to participate in ALSPAC who also had a record in the GPRD; this included 765 individuals, just under 4% of ALSPAC-eligible participants. The analysis was based on 141 participants with complete parent-reported asthma data. PRIMARY AND SECONDARY OUTCOME MEASURES The main GPRD outcome measure was whether a child had a diagnosis of asthma before they were nine. Parent-reported measures were doctor diagnosis of asthma (before mean age 7.5 years), various outcomes based on wheezing and breathlessness recorded longitudinally between 6 months and 8.5 years. Secondary outcomes were bronchial hyper-responsiveness (BHR), forced expiratory volume in 1 s/forced vital capacity ratio and skin prick test responses. RESULTS Among the 141 participants with complete parent-reported data, 26 (18%) had an asthma diagnosis before age nine. Using general practitioner (GP)-recorded asthma as the gold standard, the question 'Has a doctor ever diagnosed your child with asthma?' was both sensitive (88.5%) and specific (95.7%). 'Ever wheezed' had the highest sensitivity (100%) but low specificity (60%). More specific definitions were obtained by restricting to those who had wheezed on more than one occasion, experienced frequent wheeze and/or wheezed after the age of 3, but these measures had low sensitivities. BHR only identified 50% of those with a GP-recorded diagnosis. CONCLUSIONS Parental reports of a doctor's diagnosis agree well with a GP-recorded diagnosis. High specificity for asthma can be achieved by using detailed wheezing questions, although these definitions are likely to exclude mild cases of asthma. Our study shows that linkage between observational studies and electronic patient records has the potential to enhance epidemiological research.
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Affiliation(s)
- Rosaleen P Cornish
- School of Social and Community Medicine, University of Bristol, Bristol, UK
| | - John Henderson
- School of Social and Community Medicine, University of Bristol, Bristol, UK
| | - Andrew W Boyd
- School of Social and Community Medicine, University of Bristol, Bristol, UK
| | - Raquel Granell
- School of Social and Community Medicine, University of Bristol, Bristol, UK
| | - Tjeerd Van Staa
- Clinical Practice Research Datalink (CPRD), Medicines and Healthcare products Regulatory Agency, London, UK
| | - John Macleod
- School of Social and Community Medicine, University of Bristol, Bristol, UK
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Walters GI, Robertson AS, Moore VC, Burge PS. Cobalt asthma in metalworkers from an automotive engine valve manufacturer. Occup Med (Lond) 2014; 64:358-64. [PMID: 24727564 DOI: 10.1093/occmed/kqu043] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Cobalt asthma has previously been described in cobalt production workers, diamond polishers and glassware manufacturers. AIMS To describe a case series of occupational asthma (OA) due to cobalt, identified at the Birmingham Heartlands Occupational Lung Disease Unit, West Midlands, UK. METHODS Cases of cobalt asthma from a West Midlands' manufacturer of automotive engine valves, diagnosed between 1996 and 2005, were identified from the SHIELD database of OA. Case note data on demographics, employment status, asthma symptoms and diagnostic tests, including spirometry, peak expiratory flow (PEF) measurements, skin prick testing (SPT) and specific inhalational challenge (SIC) tests to cobalt chloride, were gathered, and descriptive statistics used to illustrate the data. RESULTS The natural history of presentations has been described in detail, as well as a case study of one of the affected workers. Fourteen metalworkers (86% male; mean age 44.9 years) were diagnosed with cobalt asthma between 1996 and 2005. Workers were principally stellite grinders, stellite welders or machine setter-operators. All workers had positive Occupational Asthma SYStem analyses of serial PEF measurements, and sensitization to cobalt chloride was demonstrated in nine workers, by SPT or SIC. CONCLUSIONS We have described a series of 14 workers with cobalt asthma from the automotive manufacturing industry, with objective evidence for sensitization. Health care workers should remain vigilant for cobalt asthma in the automotive manufacturing industry.
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Affiliation(s)
- G I Walters
- Occupational Lung Disease Unit, Birmingham Heartlands Hospital, Bordesley Green East, Birmingham B9 5SS, UK.
| | - A S Robertson
- Occupational Lung Disease Unit, Birmingham Heartlands Hospital, Bordesley Green East, Birmingham B9 5SS, UK
| | - V C Moore
- Occupational Lung Disease Unit, Birmingham Heartlands Hospital, Bordesley Green East, Birmingham B9 5SS, UK
| | - P S Burge
- Occupational Lung Disease Unit, Birmingham Heartlands Hospital, Bordesley Green East, Birmingham B9 5SS, UK
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Westergaard CG, Munck C, Helby J, Porsbjerg C, Hansen LH, Backer V. Predictors of neutrophilic airway inflammation in young smokers with asthma. J Asthma 2014; 51:341-7. [PMID: 24404796 DOI: 10.3109/02770903.2014.880718] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
INTRODUCTION Asthma is one of the most widespread chronic diseases worldwide. In spite of numerous detrimental effects on asthma, smoking is common among asthma patients. These smoking-induced aggravations of asthma may be attributed to changes in airway inflammation, which is characterized by a higher degree of neutrophilic inflammation than in non-smokers. A state of neutrophilic inflammation may lead to increased steroid resistance and an accelerated loss of lung function owing to tissue destruction. The aim of this study was to elucidate predictors of neutrophilic inflammation in young asthmatic smokers not on steroid treatment, including analysis of tobacco history and bacterial colonization. METHODS In a cross-sectional study, 52 steroid-free, current smokers with asthma were examined with induced sputum, fractional exhaled nitric oxide (FeNO), lung function, ACQ6 score, mannitol and methacholine challenge. A sample from the sputum induction was taken for bacterial analysis using 16S gene PCR technique and sequencing. RESULTS Using one-way analysis of variance and binary and linear regression models, only age and ACQ6 score were found to be significant predictors for airway neutrophilia. The investigation also included analysis for effect of pack years, current tobacco consumption, body mass index, lung function, FeNO; methacholine and mannitol responsiveness, atopy, gender, asthma history and presence of bacteria. The most common potentially pathogenic bacteria found were Streptococcus spp., Haemophilus spp. and Mycoplasma spp. CONCLUSION In this study, no tobacco-related predictors of airway neutrophilia were found, indicating that in the younger years of asthma patients who smoke, the amount of tobacco smoked in life does not influence the degree of neutrophilia. Conversely, for asthmatic smokers, neutrophilia may be induced when a certain threshold of tobacco consumption is reached.
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Harmsen L, Ulrik CS, Porsbjerg C, Thomsen SF, Holst C, Backer V. Airway hyperresponsiveness and development of lung function in adolescence and adulthood. Respir Med 2014; 108:752-7. [PMID: 24512967 DOI: 10.1016/j.rmed.2014.01.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Revised: 12/19/2013] [Accepted: 01/15/2014] [Indexed: 11/19/2022]
Abstract
BACKGROUND Long-term longitudinal studies of lung function from childhood to adulthood are important in linking our understanding of childhood risk factors to adult disease. Airway hyperresponsiveness has been shown to independently affect lung function growth in studies of adolescence. The objective of the study was to test the hypothesis that airway hyperresponsiveness has an independent deleterious effect on lung function in adolescence that extends into adulthood. METHODS A random population sample (n = 983) aged 7-17 from Copenhagen was followed longitudinally for 20 years with four examinations. RESULTS A total of 780 (79.3%) subjects contributed with lung function measurements and bronchial provocation testing. Among these, 170 (21.8%) had airway hyperresponsiveness at one examination or more during the study period. There was no difference in initial FEV1 levels between subjects with and without airway hyperresponsiveness. In a repeated measures regression model with adjustment for asthma and smoking, airway hyperresponsiveness was independently associated with reduced rates of growth in lung function in both sexes of 23 ml/year. Reduced growth rates resulted in deficits in maximal attained level of lung function at age 18, which persisted throughout the follow-up until the last examination at age 27-37 years. CONCLUSION Airway hyperresponsiveness has an independent deleterious effect on lung function development from 7 to 37 years resulting in a lower maximal attained lung function and persistent deficits in lung function in adulthood.
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Affiliation(s)
- Lotte Harmsen
- Respiratory and Allergy Research Unit, Dept. of Respiratory Medicine L, Copenhagen University Hospital Bispebjerg, Copenhagen, Denmark.
| | - Charlotte S Ulrik
- Dept. of Respiratory Medicine, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark
| | - Celeste Porsbjerg
- Respiratory and Allergy Research Unit, Dept. of Respiratory Medicine L, Copenhagen University Hospital Bispebjerg, Copenhagen, Denmark
| | - Simon F Thomsen
- Respiratory and Allergy Research Unit, Dept. of Respiratory Medicine L, Copenhagen University Hospital Bispebjerg, Copenhagen, Denmark
| | - Claus Holst
- Institute of Preventive Medicine, Copenhagen University Hospital, Centre for Health and Society, Copenhagen, Denmark
| | - Vibeke Backer
- Respiratory and Allergy Research Unit, Dept. of Respiratory Medicine L, Copenhagen University Hospital Bispebjerg, Copenhagen, Denmark
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Genetic factors account for most of the variation in serum tryptase--a twin study. Ann Allergy Asthma Immunol 2013; 111:286-9. [PMID: 24054365 DOI: 10.1016/j.anai.2013.07.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Revised: 07/08/2013] [Accepted: 07/11/2013] [Indexed: 12/11/2022]
Abstract
BACKGROUND Mast cells are involved in a number of diseases, including inflammatory diseases such as asthma. Tryptase is a known marker of mast cell burden and activity. However, little is known about the genetic influence on serum tryptase variation. Also, only few and conflicting data exist on serum tryptase in asthma. OBJECTIVE To estimate the overall contribution of genetic and environmental factors to the variation in serum tryptase and to examine the correlation between serum tryptase and asthma, rhinitis, markers of allergy, airway inflammation, and airway hyperresponsiveness (AHR) in a sample of Danish twins. METHODS A total of 575 twins underwent a skin prick test and had lung function, AHR to methacholine, exhaled nitric oxide and serum tryptase measured. Multiple regression and variance components models (using the statistical package SOLAR) were computed. RESULTS Serum tryptase values were available in 569 subjects. Intraclass correlations of serum tryptase in monozygotic and dizygotic twin pairs were 0.84 and 0.42 (P < .001). Variance decomposition showed that genetic factors accounted for 82% (95% confidence interval 74-90, P < .001) of the variation in serum tryptase. Body mass index and sex, but not asthma, rhinitis, or AHR, were correlated to serum tryptase. CONCLUSION As much as 82% of the variation in serum tryptase is due to genetic factors. Body mass index and sex, but not asthma or AHR to methacholine, correlate to serum tryptase. A genetic overlap may exist between serum tryptase and body mass index.
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Outcomes of the childhood asthma prevention study at 11.5 years. J Allergy Clin Immunol 2013; 132:1220-1222.e3. [PMID: 23900055 DOI: 10.1016/j.jaci.2013.06.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2013] [Revised: 06/06/2013] [Accepted: 06/06/2013] [Indexed: 11/21/2022]
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