Changing paradigms in the treatment of asthma
AbstractSignificant changes have occurred in relation to how chronic asthma is being treated. Emphasis has now shifted from viewing asthma as a condition of smooth muscle dysfunction to one of chronic inflammation. As such, antiinflammatory therapy forming the cornerstone of treatment represents the first important milestone in the evolution of asthma treatment. For this purpose, inhaled corticosteroid (ICS) is by far the most effective anti-inflammatory therapy. Another important milestone is the recognition of the superiority of adding long-acting β2-agonist (LABA) to ICS over escalating ICS dose alone or other forms of add-on therapies in treating asthmatic patients not responding to regular ICS alone. The effectiveness of adding LABA to ICS in treating asthma logically led to combining the two drugs into one single inhaler (salmeterol/fluticasone and budesonide/formoterol) that has the attractiveness of being user-friendly and ensuring that ICS is not missed out. The unique property of formoterol that allows for repetitive flexible dosing paved way to the concept of using Symbicort for both regular maintenance dosing and as required rescue medication. This revolutionary approach has been recently shown to provide improved asthma outcome, achieved at an overall lower or at least comparable corticosteroid intake, and may represent another evolutionary step in the treatment strategy of chronic asthma.
Masoli M, Fabian D, Holt S, et al. The global burden of asthma: executive summary of the GINA Dissemination Committee report. Allergy. 2004 May;59(5):469-78.
GINA Workshop Report (Updated 2004). Global Strategy for Asthma Management and Prevention. NIH Publication No 02-3659 Issued January, 1995. National Heart, Lung and Blood Institute, USA.
Worldwide variation in prevalence of symptoms of asthma, allergic rhinoconjunctivitis, and atopic eczema: ISAAC. The International Study of Asthma and Allergies in Childhood (ISAAC) Steering Committee. Lancet. 1998;351(9111):1225-32.
National Health and Morbidity Survey 1996-1997 Volume II. Executive Summary: Asthma. Public Health Institute, Ministry of Health Malaysia 1997.
Ng TP, Tan WC. Temporal trends and ethnic variations in asthma mortality in Singapore, 1976-1995. Thorax. 1999 Nov;54(11):990-4.
Laitinen LA, 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, parallelgroup controlled trial. J Allergy Clin Immunol. 1992 Jul;90(1):32-42.
Kaliner MA. How the current understanding of the pathophysiology of asthma influences our approach to therapy. J Allergy Clin Immunol. 1993;92(1 Pt 2):144-7.
Busse WW. Inflammation in asthma: the cornerstone of the disease and target of therapy. J Allergy Clin Immunol. 1998 Oct;102(4 Pt 2):S17-22.
Suissa S, Ernst P, Benayoun S, et al. Low-dose inhaled corticosteroids and the prevention of death from asthma. N Engl J Med. 2000 Aug;343(5):332-6.
Larche M, Robinson DS, Kay AB. The role of T lymphocytes in the pathogenesis of asthma. J Allergy Clin Immunol. 2003 Mar;111(3):450-63.
Greening AP, Ind PW, Northfield M, et al. Added salmeterol versus higher-dose corticosteroid in asthma patients with symptoms on existing inhaled corticosteroid. Lancet. 1994 Jul;344(8917):219-24.
Pauwels RA, Lofdahl CG, Postma DS, et al. Effect of inhaled formoterol and budesonide on exacerbations of asthma. Formoterol and Corticosteroids Establishing Therapy (FACET) International Study Group. N Engl J Med. 1997 Nov;337(20):1405-11.
Shrewsbury S, Pyke S, Britton M. Meta-analysis of increased dose of inhaled steroid or addition of salmeterol in symptomatic asthma (MIASMA). BMJ. 2000;320:1368-73.
Howarth PH, Beckett P, Dahl R. The effect of long-acting beta2-agonists on airway inflammation in asthmatic patients. Respir Med. 2000 Oct;94 Suppl F:S22-5.
Baluk P, McDonald DM. The beta 2-adrenergic receptor agonist formoterol reduces microvascular leakage by inhibiting endothelial gap formation. Am J Physiol. 1994;266(4 Pt 1):L461-8.
Nials AT, Ball DI, Butchers PR, et al. Formoterol on airway smooth muscle and human lung mast cells: a comparison with salbutamol and salmeterol. Eur J Pharmacol. 1994 Jan;251(2-3):127-35.
Barnes PJ. Scientific rationale for inhaled combination therapy with long-acting beta2-agonists and corticosteroids. Eur Respir J. 2002 Jan;19(1):182-91.
Roth M, Johnson PR, Rudiger JJ, et al. Interaction between glucocorticoids and beta2 agonists on bronchial airway smooth muscle cells through synchronised cellular signalling. Lancet. Oct 26;360(9342):1293-9.
Holt S, Suder A, Weatherall M, et al. Dose-response relation of inhaled fluticasone propionate in adolescents and adults with asthma: meta-analysis. BMJ. 2001;323:253-6.
Chapman KR, Ringdal N, Backer V, et al. Salmeterol and fluticasone propionate (50/250 microg) administered via combination Diskus inhaler: as effective as when given via separate Diskus inhalers. Can Respir J. 1999 JanFeb;6(1):45-51.
Rosenhall L, Borg S, Andersson F, et al. Budesonide/formoterol in a single inhaler (Symbicort) reduces healthcare costs compared with separate inhalers in the treatment of asthma over 12 months. Int J Clin Pract. 2003 Oct;57(8):662-7.
Palmqvist M, Persson G, Lazer L, et al. Inhaled dry-powder formoterol and salmeterol in asthmatic patients: onset of action, duration of effect and potency. Eur Respir J. 1997 Nov;10(11):2484-9.
Pauwels RA, Sears MR, Campbell M, et al. Formoterol as relief medication in asthma: a worldwide safety and effectiveness trial. Eur Respir J. 2003 Nov;22(5):787-94.
Totterman KJ, Huhti L, Sutinen E, et al. Tolerability to high doses of formoterol and terbutaline via Turbuhaler for 3 days in stable asthmatic patients. Eur Respir J. 1998 Sep;12(3):573-9.
Lotvall J. Pharmacological similarities and differences between beta2-agonists. Respir Med. 2001 Aug;95 Suppl B:S7-11.
Aalbers R, Backer V, Kava TT, et al. Adjustable maintenance dosing with budesonide/formoterol compared with fixed-dose salmeterol/fluticasone in moderate to severe asthma. Curr Med Res Opin. 2004;20(2):225-40.
Scicchitano R, Aalbers R, Ukena D, et al. Efficacy and safety of budesonide/formoterol single inhaler therapy versus a higher dose of budesonide in moderate to severe asthma. Curr Med Res Opin. 2004 Sep;20(9):1403-18.
O'Byrne PM, Bisgaard H, Godard PP, et al. Symbicort Single Inhaler Therapy compared with a fixed higher dose budesonide and fixed dose Symbicort in asthma. Am J Respir Crit Care Med. 2005 Jan 15;171(2):129-36.
Kemp JP. Recent advances in the management of asthma using leukotriene modifiers. Am J Respir Med. 2003;2(2):139-56.
Ducharme FM. Inhaled glucocorticoids versus leukotriene receptor antagonists as single agent asthma treatment: systematic review of current evidence. BMJ. 2003;326:621.
Lipworth BJ, White PS. Allergic inflammation in the unified airway: start with the nose. Thorax. 2000 Oct;55(10):878-81.
Bjermer L, Diamant Z. The use of leukotriene receptor antagonists (LTRAs) as complementary therapy in asthma. Monaldi Arch Chest Dis. 2002 Feb;57(1):76-83.
Bisgaard H. A randomized trial of montelukast in respiratory syncytial virus postbronchiolitis. Am J Respir Crit Care Med. 2003 Feb 1;167(3):379-83.
Ringdal N. Long-acting beta2-agonists or leukotriene receptor antagonists as add-on therapy to inhaled corticosteroids for the treatment of persistent asthma. Drugs. 2003;63 Suppl 2;21-33.
Lim TO, Suppiah A, Ismail F, et al. Morbidity associated with asthma and audit of asthma treatment in out-patient clinics. Singapore Med J. 1992 Apr;33(2):174-6.
Lai CK, De Guia TS, Kim YY, et al. Asthma control in the Asia-Pacific region: the Asthma Insights and Reality in AsiaPacific Study. J Allergy Clin Immunol. 2003 Feb;111(2):263-8.
Loh LC, Wong PC. Asthma prescribing practices between government and private doctors in Malaysia - A nationwide questionnaire survey. Asian Pac J Allergy Immunol. 2005 Mar;23(1):7-17.