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Achieving asthma control in practice: understanding the reasons for poor control

This panel discussion from September 2008 in Aberdeen addresses the challenges of achieving asthma control in clinical practice. Topics covered include identifying causes of poor control, managing comorbidities, and addressing incorrect inhaler choice or poor technique.

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Achieving asthma control in practice: understanding the reasons for poor control

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  1. Achieving asthma control in practice: understanding the reasons for poor control September 2008

  2. International panel discussion, Aberdeen, Sept 2007 How to develop tools for use in primary care: • To identify causes of poor asthma control • To manage causes of poor asthma control We're not treating asthma; we're treating patients. Many of our patients would not be eligible for inclusion in randomised controlled trials because of comorbidities and other factors. Thus, the asthma guidelines, which are based on results of these trials, often do not provide the answers we need for patient care, particularly in the primary care setting. -Dr. John Haughney Haughney J et al. Achieving asthma control in practice: understanding the reasons for poor control. Respir Med. 2008;102:1681–93.

  3. What is asthma control?As defined by the Global Initiative for Asthma (GINA), 2007 • Minimal to no daytime asthma symptoms • No limitations on activities • No nocturnal symptoms or awakenings • Minimal to no need for reliever or rescue therapy • Normal lung function (FEV1 or PEF) • No exacerbations www.ginasthma.org

  4. Reasons for poor asthma control • Wrong diagnosis or confounding illness • Incorrect choice of inhaler or poor technique • Concurrent smoking • Concomitant rhinitis • Unintentional or intentional nonadherence • Individual variation in treatment response • Undertreatment Haughney J et al. Respir Med. 2008;102:1681–93.

  5. Addressing poor asthma controlStep 1: Confirm the diagnosis of asthma • If the patient is not responding as expected to asthma therapy: • Confirm the asthma diagnosis and rule out (or in) confounding illness before changing or increasing medications • Tools for diagnosing asthma must be stratified by age • Objective measures of reversible airflow obstruction (spirometry, PEF) are important if available IPCRG Guidelines: diagnosis of respiratory diseases in primary care. Prim Care Respir J. 2006;15:20–34.

  6. Diagnosing asthma in primary careIPCRG guidelines. Prim Care Respir J. 2006;15:20–34. • Compatible clinical history • Episodic or persistent dyspnoea, wheeze, tightness, cough • Triggers (allergic, irritant) • Risk factors for asthma development • Consider occupational asthma for adults with recent onset • Objective evidence • Spirometry or peak expiratory flow • Bronchoprovocation test (methacholine challenge) • Ancillary tests • Chest x-ray • Eosinophils, IgE level • Allergy testing • Exhaled nitric oxide • Induced sputum

  7. Diagnosing asthma in children • Remember that young children commonly wheeze with colds • Differentials for wheezing include respiratory (upper and lower) and non-respiratory causes: • Upper airway: allergic diseases • Obstruction of large airway: foreign body, vocal cord dysfunction, vascular rings, laryngeal webs, tracheomalacia, or stenosis • Obstruction of small airways: viral bronchiolitis, cystic fibrosis, bronchopulmonary dysplasia, heart disease • Other: aspiration (gastro-oesophageal reflux disease) • Spirometry is usually impractical for patients < 5 years old Bush A. Diagnosis of asthma in children under five. Prim Care Respir J. 2007;16:7–15.

  8. Modified Asthma Prediction Index (mAPI)A clinical index defining asthma risk in 2–3 year olds For a child ≥2 years old with a history of ≥4 wheezing episodes (≥1 confirmed by a physician), the likelihood of active asthma at age 6-13 yrs increases if the child has: • One of three major risk factors: • Parental history of asthma • Physician-diagnosed atopic dermatitis • Allergic sensitization to ≥1 aeroallergen • OR two of three minor risk factors: • Allergic sensitization to milk, egg, or peanuts • Wheezing unrelated to colds • Blood eosinophils ≥4% Guilbert TW et al. J Allergy Clin Immunol. 2004;114:1282–7.

  9. Diagnosing asthma in adults • Differentiate between asthma and chronic obstructive pulmonary disease (COPD) • Identify triggers such as smoking, pet exposure, occupational exposure • Common differential diagnoses: • COPD, cardiac disease, laryngeal, tracheal, or lung tumour, bronchiectasis, foreign body, interstitial lung disease, pulmonary emboli, aspiration, vocal cord dysfunction, hyperventilation IPCRG Guidelines: diagnosis of respiratory diseases in primary care. Prim Care Respir J. 2006;15:20–34.

  10. Diagnosing asthma in adultsComorbidities can worsen asthma symptoms— identify and treat them: • allergic rhinitis • COPD • gastro-oesophageal reflux disease (GERD) • respiratory infection • cardiac disorders • anaemia • vocal cord dysfunction

  11. Addressing poor asthma controlIncorrect inhaler choice or poor technique • There is no clinical difference between inhaler devices when used correctly, but each type requires a different pattern of inhalation for optimal drug delivery to the lungs • Problems with inhaler technique are common in clinical practice & can lead to poor asthma control • Asthma control worsens as the number of mistakes in inhaler technique increases • All patients should be trained in technique, and trainers should be competent with the inhalation technique

  12. Inhaler choice and techniqueKey recommendations: Take patient preference into account when choosing the inhaler device Simplify the regimen and do not mix inhaler device types The choice of steroid inhaler is most important because of the narrower therapeutic window Invest the time to train each patient in proper inhaler technique: Observe technique & let patient observe self (using video demonstrations) Devices to check technique & maintain trained technique are available (eg, 2Tone Trainer & Aerochamber Plus spacer for metered dose inhalers; In-Check Dial, Turbuhaler whistle, Novolizer for dry powder inhalers) Recheck inhaler technique on each revisit Haughney J et al. Respir Med. 2008;102:1681–93.

  13. Resources on inhaler use • Inhaler & spacer diagrams on GINA website: • http://www.ginasthma.com/Userfiles/inhaler_charts.pdf • American College of Chest Physicians/American College of Asthma, Allergy, and Immunology guidelines: • Dolovich et al. Chest. 2005;127:335-371. • Educational CD-Roms by Ontario Thoracic Society Provider Education Program: • http://www.on.lung.ca/Health-Care-Professionals/Provider-Education-Program/CD-ROMS.php • Schematic cartoons on the Asthma UK website: • http://www.asthma.org.uk/using_your.html

  14. Resources on inhaler use (cont.) • Correct Inhaler Techniques and Common Mistakes • June 2008 newsletter, National Asthma Council, Australia:http://www.nationalasthma.org.au/html/newsletter/2008/nl_08_006.asp#s2 • Woolcock Institute of Medical Research:http://www.woolcock.org.au/PDF/PR/WIMR_Press_Release_AsthmaMeds_June2008.pdf • Asthma Management Handbook 2006, National Asthma Council, Australia: • Use & care of spacers:http://www.nationalasthma.org.au/cms/index.php?option=com_content&task=view&id=200&Itemid=147 • Delivery devices:http://www.nationalasthma.org.au/cms/index.php?option=com_content&task=view&id=90&Itemid=112

  15. Addressing poor asthma controlConcurrent smoking • Smoking adversely impacts asthma control • Current smokers are almost 3 times more likely than non-smokers to be hospitalised for their asthma over a 12-month period • Why does smoking adversely impact asthma? • Asthma misdiagnosed as COPD or concomitant COPD • Relative steroid resistance Price D et al. Clin Exp Allergy. 2005;35:282–7.

  16. Inhaled steroids are less effective in smokers than nonsmokers with asthma The pattern of airway inflammation differs Smokers have a higher percentage of neutrophils in induced sputum, and steroids are not very effective in reducing neutrophils. Smoking produces oxidative stress The oxidative stress produced by smoking impairs the activity of histone deacetylase-2 (HDAC2), resulting in reduced anti-inflammatory activity of steroids. Smoking triggers leukotriene production Leukotrienes are not reduced by steroid therapy. Boulet LP et al. Chest. 2006;129:661–8. Barnes PJ et al. Lancet. 2004;363:731–3. Fauler J et al. Eur J Clin Invest. 1997;27:43–7.

  17. Steroid resistance in smokers with asthma Non-Smoking Asthma Smoking Asthma Cigarette smoke Inflammatory stimuli Corticosteroids Oxidative stress Peroxynitrite GR NF-B NF-B  HDAC2  HDAC2 Histone acetylation Histone acetylation Steroid resistance Steroid response • GM-CSF • IL-8 • eotaxin • GM-CSF • IL-8 • eotaxin GM-CSF IL-8 eotaxin  Histone acetylation GR = glucocorticoid receptors; HDAC2 = histone deacetylase-2; NF- B = nuclear factor- B

  18. Clinical approach to smoking • Tools • Take a smoking history • Investigate the possibility of COPD • IPCRG guidance includes tool to differentiate asthma from COPD* • Solutions • Encourage smokers to quit! • IPCRG guidance on smoking cessation: http://www.theipcrg.org/smoking/index.php • Try alternative therapy: • Leukotriene receptor antagonist • Possibly theophylline *IPCRG Guidelines: diagnosis of respiratory diseases in primary care. Prim Care Respir J. 2006;15:20–34.

  19. Addressing poor asthma controlConcomitant rhinitis • Patients with asthma & concomitant rhinitis use more health care resources than those without rhinitis • In epidemiologic studies in the UK: • Adults with asthma & concomitant rhinitis were 50% more likely to be hospitalised for their asthma & significantly more likely to visit their primary care physician than those without rhinitis • Children with asthma & concomitant rhinitis had double the likelihood of being hospitalised and significantly increased likelihood of a physician visit for asthma than those without rhinitis • >50% of patients with asthma have rhinitis • Both allergic & nonallergic rhinitis are linked to asthma Price D et alClin Exp Allergy. 2005;35:282–7. Thomas M et al. Pediatrics. 2005;115:129–34.

  20. Evidence linking asthma & rhinitis • >50% of patients with asthma have rhinitis • Similar epidemiology • Common triggers • Similar pattern of inflammation: • T helper type 2 cells, mast cells, eosinophils • Nasal challenge results in asthmatic inflammation & vice versa • Rhinitis predicts development of asthma Thomas M. BMC Pulm Med. 2006;6:S4.

  21. Does treatment of rhinitis improve asthma control? Preliminary evidence suggests that it does improve asthma control In the COMPACT trial, patients with comorbid rhinitis who received budesonide plus montelukast, a leukotriene receptor antagonist effective in treating rhinitis symptoms in patients with asthma, showed significantly greater improvement in morning PEF than the group receiving monotherapy with doubled dose of budesonide. This treatment difference was not seen among patients without comorbid rhinitis, suggesting that the effects of montelukast on rhinitis improved lung function. Price DB et al. Allergy. 2006;61:737–42.

  22. Clinical approach to rhinitis • Diagnosing rhinitis • Use the International Study of Asthma and Allergies in Childhood (ISAAC) question: • "Do you have an itchy, sneezy, runny, or blocked nose when you don't have a cold?“ • Take a good history & examine the nose • Assess severity – as relates to asthma control • Treat the inflammation of both asthma & rhinitis • Target upper & lower airways concomitantly or • Combine upper plus lower airway therapies IPCRG Guidelines: management of allergic rhinitis. Prim Care Respir J. 2006;15:58–70.

  23. Treatment of comorbid rhinitis & asthma

  24. Addressing poor asthma controlUnintentional & intentional nonadherence • Nonadherence to asthma therapy, particularly to inhaled steroids, is a common problem contributing to poor asthma control • Nonadherence is often a hidden problem as assessment of adherence is often not included in routine asthma review • Barriers to assessing adherence: • Patient and physician may prefer to avoid the subject • Lack of clear, easy methods for addressing barriers to adherence • Perception that little can be done? • Appreciating the factors involved is the first step toward improving adherence Horne R. Chest. 2006;130:65S–72S.

  25. Unintentional versus intentional nonadherence Intentional nonadherence derives from the balance between the patient’s beliefs about the personal necessity of taking a given medication relative to any concerns about taking it Horne R et al. 2005. National Co-ordinating Centre for NHS Service Delivery and Organisation R&D, London.

  26. Nonadherence: identifying the causes • Tools for identifying & assessing nonadherence: • Beliefs about Medicines Questionnaire (BMQ) — developed to measure necessity beliefs and concerns • Medication Adherence Report Scale (MARS) — developed to assess patient adherence • Minimal Asthma Assessment Tool (MAAT) — undergoing pilot testing as a simple, self-administered patient questionnaire for use before a clinical consultation to evaluate asthma control, adherence to medication, and comorbidities such as allergic rhinitis and smoking • Interventions to facilitate optimal adherence are likely to be more effective if they: • Facilitate honest discussion of adherence behaviour • Identify the mix of perceptual & practical barriers for the individual patient • Help clinicians to elicit and respond to patient beliefs and concerns • We need to tailor the intervention & support according to specific barriers & patient preferences Haughney J et al. Respir Med. 2008;102:1681–93.

  27. Addressing poor asthma controlIndividual variation in treatment response Randomised controlled trials (RCTs) are the basis of recommendations made by clinical guidelines. However, several factors limit our ability to generalise RCT results to our patients. • Fewer than 10% of people with asthma in a general practice population are eligible for the typical RCT • Patient adherence to therapy may be better in an RCT than in the real world • The definition of “response” to therapy in an RCT (eg, FEV1 improvement) may not correspond to results relevant for our patients (eg, improved asthma control, improved quality of life) • The inclusion/exclusion criteria can influence RCT results (eg, requirement for bronchodilator reversibility may favour β agonist) • Group mean data from RCTs may not predict individual patient response Haughney J et al. Respir Med. 2008;102:1681–93.

  28. Individual variation in treatment response Distribution of FEV1 responses among adults with chronic asthma after 12 weeks of therapy with inhaled beclometasone (white bars) or oral montelukast (striped bars). The mean FEV1 improvement from baseline was 13.1% for beclometasone & 7.4% for montelukast. Malmstrom K et al. Ann Intern Med. 1999;130:487–95 .

  29. Individual variation in treatment response Individual patient versus average patient Intraindividual response profile to therapy among children and adolescents with persistent asthma. Individual patient responses (change from baseline in asthma control days) suggest that, while some patients responded to both inhaled steroid and montelukast, others showed a better response to one or the other. Zeiger RS et al. J Allergy Clin Immunol. 2006;117:45–52.

  30. Difficulty in capturing & demonstrating subjective benefit in clinical trialsFactors driving clinical trials: • Regulatory requirements • The needs of industry • History • what's been done in the past & is therefore still expected • Ease of measuring certain endpoints • Available technology to measure these endpoints • The need to focus on short-term events of asthma • The limited number of agents available for treating asthma • The need to remove all possible confounding factors to allow assessment of the intervention studied Haughney J et al. Respir Med. 2008;102:1681–93.

  31. Real world measures are needed for clinical trials Haughney J et al. Respir Med. 2008;102:1681–93.

  32. Addressing poor asthma controlNext steps—IPCRG GOALS • Develop tools to aid asthma diagnosis and management in primary care • Translate tools into local languages and adapt them to address cultural differences in perceptions about asthma • Test all tools to address issue of low levels of health literacy in many countries • Coordinate efforts between the IPCRG, member countries, and patients’ organisations to adapt tools for individual countries

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