Abstract
Background: There are few data in asthma relating airway physiology, inflammation and remodelling and the relative effects of inhaled corticosteroid (ICS) treatment on these parameters. A study of the relationships between spirometric indices, airway inflammation, airway remodelling, and bronchial hyperreactivity (BHR) before and after treatment with high dose inhaled fluticasone propionate (FP 750 µg bd) was performed in a group of patients with relatively mild but symptomatic asthma.
Methods: A double blind, randomised, placebo controlled, parallel group study of inhaled FP was performed in 35 asthmatic patients. Bronchoalveolar lavage (BAL) and airway biopsy studies were carried out at baseline and after 3 and 12 months of treatment. Twenty two normal healthy non-asthmatic subjects acted as controls.
Results: BAL fluid eosinophils, mast cells, and epithelial cells were significantly higher in asthmatic patients than in controls at baseline (p<0.01). Subepithelial reticular basement membrane (rbm) thickness was variable, but overall was increased in asthmatic patients compared with controls (p<0.01). Multiple regression analysis explained 40% of the variability in BHR, 21% related to rbm thickness, 11% to BAL epithelial cells, and 8% to BAL eosinophils. The longitudinal data corroborated the cross sectional model. Forced expiratory volume in 1 second improved after 3 months of treatment with FP with no further improvement at 12 months. PD20 improved throughout the study. BAL inflammatory cells decreased following 3 months of treatment with no further improvement at 12 months (p<0.05 v placebo). Rbm thickness decreased in the FP group, but only after 12 months of treatment (mean change –1.9, 95% CI –3 to –0.7 µm; p<0.01 v baseline, p<0.05 v placebo). A third of the improvement in BHR with FP was associated with early changes in inflammation, but the more progressive and larger improvement was associated with the later improvement in airway remodelling.
Conclusion: Physiology, airway inflammation and remodelling in asthma are interrelated and improve with ICS. Changes are not temporally concordant, with prolonged treatment necessary for maximal benefit in remodelling and PD20. Determining the appropriate dose of inhaled steroids only by reference to symptoms and lung function, as specified in current international guidelines, and even against indices of inflammation may be over simplistic. The results of this study support the need for early and long term intervention with ICS, even in patients with relatively mild asthma.
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Selected References
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- Beach J. R., Young C. L., Avery A. J., Stenton S. C., Dennis J. H., Walters E. H., Hendrick D. J. Measurement of airway responsiveness to methacholine: relative importance of the precision of drug delivery and the method of assessing response. Thorax. 1993 Mar;48(3):239–243. doi: 10.1136/thx.48.3.239. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Booth H., Richmond I., Ward C., Gardiner P. V., Harkawat R., Walters E. H. Effect of high dose inhaled fluticasone propionate on airway inflammation in asthma. Am J Respir Crit Care Med. 1995 Jul;152(1):45–52. doi: 10.1164/ajrccm.152.1.7599861. [DOI] [PubMed] [Google Scholar]
- Boulet L. P., Turcotte H., Laviolette M., Naud F., Bernier M. C., Martel S., Chakir J. Airway hyperresponsiveness, inflammation, and subepithelial collagen deposition in recently diagnosed versus long-standing mild asthma. Influence of inhaled corticosteroids. Am J Respir Crit Care Med. 2000 Oct;162(4 Pt 1):1308–1313. doi: 10.1164/ajrccm.162.4.9910051. [DOI] [PubMed] [Google Scholar]
- Bousquet J., Jeffery P. K., Busse W. W., Johnson M., Vignola A. M. Asthma. From bronchoconstriction to airways inflammation and remodeling. Am J Respir Crit Care Med. 2000 May;161(5):1720–1745. doi: 10.1164/ajrccm.161.5.9903102. [DOI] [PubMed] [Google Scholar]
- Chetta A., Foresi A., Del Donno M., Bertorelli G., Pesci A., Olivieri D. Airways remodeling is a distinctive feature of asthma and is related to severity of disease. Chest. 1997 Apr;111(4):852–857. doi: 10.1378/chest.111.4.852. [DOI] [PubMed] [Google Scholar]
- Chinn S., Burney P., Jarvis D., Luczynska C. Variation in bronchial responsiveness in the European Community Respiratory Health Survey (ECRHS). Eur Respir J. 1997 Nov;10(11):2495–2501. doi: 10.1183/09031936.97.10112495. [DOI] [PubMed] [Google Scholar]
- Chu H. W., Halliday J. L., Martin R. J., Leung D. Y., Szefler S. J., Wenzel S. E. Collagen deposition in large airways may not differentiate severe asthma from milder forms of the disease. Am J Respir Crit Care Med. 1998 Dec;158(6):1936–1944. doi: 10.1164/ajrccm.158.6.9712073. [DOI] [PubMed] [Google Scholar]
- Chung K. F. Unmet needs in adult asthma. Clin Exp Allergy. 2000 Jun;30 (Suppl 1):66–69. doi: 10.1046/j.1365-2222.2000.00101.x. [DOI] [PubMed] [Google Scholar]
- Duddridge M., Ward C., Hendrick D. J., Walters E. H. Changes in bronchoalveolar lavage inflammatory cells in asthmatic patients treated with high dose inhaled beclomethasone dipropionate. Eur Respir J. 1993 Apr;6(4):489–497. [PubMed] [Google Scholar]
- Elias J. A. Airway remodeling in asthma. Unanswered questions. Am J Respir Crit Care Med. 2000 Mar;161(3 Pt 2):S168–S171. doi: 10.1164/ajrccm.161.supplement_2.a1q4-4. [DOI] [PubMed] [Google Scholar]
- Fish J. E., Peters S. P. Airway remodeling and persistent airway obstruction in asthma. J Allergy Clin Immunol. 1999 Sep;104(3 Pt 1):509–516. doi: 10.1016/s0091-6749(99)70315-5. [DOI] [PubMed] [Google Scholar]
- Haahtela T. The long-term influence of therapeutic interventions in asthma with emphasis on inhaled steroids and early disease. Clin Exp Allergy. 1998 Nov;28 (Suppl 5):133–173. doi: 10.1046/j.1365-2222.1998.028s5133.x. [DOI] [PubMed] [Google Scholar]
- Hargreave F. E. Induced sputum for the investigation of airway inflammation: evidence for its clinical application. Can Respir J. 1999 Mar-Apr;6(2):169–174. doi: 10.1155/1999/921708. [DOI] [PubMed] [Google Scholar]
- Holgate S. T. The role of mast cells and basophils in inflammation. Clin Exp Allergy. 2000 Jun;30 (Suppl 1):28–32. doi: 10.1046/j.1365-2222.2000.00093.x. [DOI] [PubMed] [Google Scholar]
- Hoshino M., Nakamura Y., Sim J. J., Yamashiro Y., Uchida K., Hosaka K., Isogai S. Inhaled corticosteroid reduced lamina reticularis of the basement membrane by modulation of insulin-like growth factor (IGF)-I expression in bronchial asthma. Clin Exp Allergy. 1998 May;28(5):568–577. doi: 10.1046/j.1365-2222.1998.00277.x. [DOI] [PubMed] [Google Scholar]
- Hoshino M., Takahashi M., Takai Y., Sim J. Inhaled corticosteroids decrease subepithelial collagen deposition by modulation of the balance between matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 expression in asthma. J Allergy Clin Immunol. 1999 Aug;104(2 Pt 1):356–363. doi: 10.1016/s0091-6749(99)70379-9. [DOI] [PubMed] [Google Scholar]
- James A., Carroll N. Airway smooth muscle in health and disease; methods of measurement and relation to function. Eur Respir J. 2000 Apr;15(4):782–789. doi: 10.1034/j.1399-3003.2000.15d25.x. [DOI] [PubMed] [Google Scholar]
- James A., Carroll N. Theoretic effects of mucus gland discharge on airway resistance in asthma. Chest. 1995 Mar;107(3 Suppl):110S–110S. doi: 10.1378/chest.107.3_supplement.110s. [DOI] [PubMed] [Google Scholar]
- Jeffery P. K., Godfrey R. W., Adelroth E., Nelson F., Rogers A., Johansson S. A. Effects of treatment on airway inflammation and thickening of basement membrane reticular collagen in asthma. A quantitative light and electron microscopic study. Am Rev Respir Dis. 1992 Apr;145(4 Pt 1):890–899. doi: 10.1164/ajrccm/145.4_Pt_1.890. [DOI] [PubMed] [Google Scholar]
- Laitinen A., Altraja A., Kämpe M., Linden M., Virtanen I., Laitinen L. A. Tenascin is increased in airway basement membrane of asthmatics and decreased by an inhaled steroid. Am J Respir Crit Care Med. 1997 Sep;156(3 Pt 1):951–958. doi: 10.1164/ajrccm.156.3.9610084. [DOI] [PubMed] [Google Scholar]
- Laitinen L. A., Laitinen A., Altraja A., Virtanen I., Kämpe M., Simonsson B. G., Karlsson S. E., Håkansson L., Venge P., Sillastu H. Bronchial biopsy findings in intermittent or "early" asthma. J Allergy Clin Immunol. 1996 Nov;98(5 Pt 2):S3–S40. [PubMed] [Google Scholar]
- Laitinen L. A., Laitinen A., Haahtela T. A comparative study of the effects of an inhaled corticosteroid, budesonide, and a beta 2-agonist, terbutaline, on airway inflammation in newly diagnosed asthma: a randomized, double-blind, parallel-group controlled trial. J Allergy Clin Immunol. 1992 Jul;90(1):32–42. doi: 10.1016/s0091-6749(06)80008-4. [DOI] [PubMed] [Google Scholar]
- Laprise C., Laviolette M., Boutet M., Boulet L. P. Asymptomatic airway hyperresponsiveness: relationships with airway inflammation and remodelling. Eur Respir J. 1999 Jul;14(1):63–73. doi: 10.1034/j.1399-3003.1999.14a12.x. [DOI] [PubMed] [Google Scholar]
- Laursen L. C., Taudorf E., Borgeskov S., Kobayasi T., Jensen H., Weeke B. Fiberoptic bronchoscopy and bronchial mucosal biopsies in asthmatics undergoing long-term high-dose budesonide aerosol treatment. Allergy. 1988 May;43(4):284–288. doi: 10.1111/j.1398-9995.1988.tb00901.x. [DOI] [PubMed] [Google Scholar]
- Lemière C., Pizzichini M. M., Balkissoon R., Clelland L., Efthimiadis A., O'Shaughnessy D., Dolovich J., Hargreave F. E. Diagnosing occupational asthma: use of induced sputum. Eur Respir J. 1999 Mar;13(3):482–488. doi: 10.1183/09031936.99.13348299. [DOI] [PubMed] [Google Scholar]
- Li X., Ward C., Thien F., Bish R., Bamford T., Bao X., Bailey M., Wilson J. W., Haydn Walters E. An antiinflammatory effect of salmeterol, a long-acting beta(2) agonist, assessed in airway biopsies and bronchoalveolar lavage in asthma. Am J Respir Crit Care Med. 1999 Nov;160(5 Pt 1):1493–1499. doi: 10.1164/ajrccm.160.5.9811052. [DOI] [PubMed] [Google Scholar]
- Little S. A., Chalmers G. W., MacLeod K. J., McSharry C., Thomson N. C. Non-invasive markers of airway inflammation as predictors of oral steroid responsiveness in asthma. Thorax. 2000 Mar;55(3):232–234. doi: 10.1136/thorax.55.3.232. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Orsida B. E., Li X., Hickey B., Thien F., Wilson J. W., Walters E. H. Vascularity in asthmatic airways: relation to inhaled steroid dose. Thorax. 1999 Apr;54(4):289–295. doi: 10.1136/thx.54.4.289. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Paredi P., Leckie M. J., Horvath I., Allegra L., Kharitonov S. A., Barnes P. J. Changes in exhaled carbon monoxide and nitric oxide levels following allergen challenge in patients with asthma. Eur Respir J. 1999 Jan;13(1):48–52. doi: 10.1183/09031936.99.13104899. [DOI] [PubMed] [Google Scholar]
- Roche W. R., Beasley R., Williams J. H., Holgate S. T. Subepithelial fibrosis in the bronchi of asthmatics. Lancet. 1989 Mar 11;1(8637):520–524. doi: 10.1016/s0140-6736(89)90067-6. [DOI] [PubMed] [Google Scholar]
- Silkoff P. E. Noninvasive measurement of airway inflammation using exhaled nitric oxide and induced sputum. Current status and future use. Clin Chest Med. 2000 Jun;21(2):345–360. doi: 10.1016/s0272-5231(05)70271-9. [DOI] [PubMed] [Google Scholar]
- Sont J. K., Willems L. N., Bel E. H., van Krieken J. H., Vandenbroucke J. P., Sterk P. J. Clinical control and histopathologic outcome of asthma when using airway hyperresponsiveness as an additional guide to long-term treatment. The AMPUL Study Group. Am J Respir Crit Care Med. 1999 Apr;159(4 Pt 1):1043–1051. doi: 10.1164/ajrccm.159.4.9806052. [DOI] [PubMed] [Google Scholar]
- Trigg C. J., Manolitsas N. D., Wang J., Calderón M. A., McAulay A., Jordan S. E., Herdman M. J., Jhalli N., Duddle J. M., Hamilton S. A. Placebo-controlled immunopathologic study of four months of inhaled corticosteroids in asthma. Am J Respir Crit Care Med. 1994 Jul;150(1):17–22. doi: 10.1164/ajrccm.150.1.8025745. [DOI] [PubMed] [Google Scholar]
- Wiggs B. R., Bosken C., Paré P. D., James A., Hogg J. C. A model of airway narrowing in asthma and in chronic obstructive pulmonary disease. Am Rev Respir Dis. 1992 Jun;145(6):1251–1258. doi: 10.1164/ajrccm/145.6.1251. [DOI] [PubMed] [Google Scholar]
- Wilson J. W., Li X. The measurement of reticular basement membrane and submucosal collagen in the asthmatic airway. Clin Exp Allergy. 1997 Apr;27(4):363–371. [PubMed] [Google Scholar]
- van der Molen T., Kerstjens H. A. Starting inhaled corticosteroids in asthma: when, how high, and how long. Eur Respir J. 2000 Jan;15(1):3–4. doi: 10.1183/09031936.00.15100300. [DOI] [PubMed] [Google Scholar]