NEWS NP S. Inside. Defining COPD. Is it COPD? National Prescribing Service Newsletter

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1 NP S NEWS National Prescribing Service Newsletter ISSN Aug 99 Inside Bronchodilators and corticosteroids: Their use in COPD Give it up the best advice for COPD patients: NRT can help This doesn t go with that: Medications COPD patients should avoid Recommended vaccinations Analysis of otitis media case study Defining COPD The term chronic obstructive pulmonary disease (COPD) is used throughout this newsletter and can be used interchangeably with chronic obstructive airways disease (COAD), chronic airflow limitation (CAL) or chronic obstructive lung disease (COLD). COPD is a chronic, slowly progressive disorder characterised by the presence of airway obstruction which may (or may not) be partially reversible by bronchodilator (or other) therapy. 1,2,3 Is it COPD? Patients with COPD have usually been smokers of 20 cigarettes per day for 20 years or more before symptoms develop. They commonly present in the fifth decade with productive cough or an acute chest illness. Dyspnoea on effort usually does not occur until the sixth or seventh decade. 3 In some susceptible patients, symptoms can present earlier. Diagnosis is usually suggested by symptoms but can only be established by objective measurement using spirometry. 2 Forced expiratory volume (FEV 1 ) is the preferred measurement. It has less variability than other measures of airway dynamics and is more accurately predictable from age, sex and height. 3 If peak expiratory flow rate is used, serial recordings over one week are needed to confirm the absence of variability. However, the ratio of FEV 1 to forced vital capacity is needed for a definite diagnosis. A chest x-ray excludes other pathologies but cannot positively diagnose COPD. 2 The only treatment proven to slow the progression of COPD is smoking cessation. Other drug treatments have not been proven to affect the natural history of COPD. Treatment using drugs or non-drug measures should therefore focus on improving the patient s quality of life. It is often difficult, and sometimes impossible, to distinguish COPD from the persistent airflow limitation of chronic asthma in older patients. 4 It is important, however, to make this distinction wherever possible because if the patient has asthma a stepped asthma management plan should be instituted. (For more information on the diagnostic indicators of asthma, see the Asthma Management Handbook 1998 available from the National Asthma Campaign, phone: ) The signs and symptoms of COPD vary with the severity of the disease (see table below). Patients will have lost significant lung function (FEV % predicted) by the time they present with symptoms. Mild no abnormal signs FEV1 smoker s cough 60-80% little or no breathlessness predicted Moderate breathlessness (± wheeze) FEV1 on moderate exertion 40-59% cough (± sputum) predicted variable abnormal signs (general reduction in breath sounds, presence of wheeze) Severe breathlessness on any exertion/at rest FEV1 <40% wheeze and cough often predicted prominent lung overinflation usual cyanosis, peripheral oedema and polycythaemia in advanced disease, especially during exacerbations Source: British Thoracic Society Guidelines for Management of COPD. 2 National Prescribing Service Limited ACN an independent, non-profit, educational organisation supporting quality prescribing in Australia.

2 Prescribing pointers Bronchodilators and corticosteroids: Their use in stable COPD Bronchodilators Many patients with COPD respond sufficiently to bronchodilator therapy to obtain significant shortterm symptomatic relief. 1 The usefulness of a bronchodilator for an individual can only be assessed by a therapeutic trial accepting as end points either objective improvement in lung function or subjective improvement in symptom control, such as better exercise capacity or reduced breathlessness. 2 Bronchodilators can improve symptoms, the FEV 1, forced vital capacity or exercise tolerance independently of each other. 2 Spirometric changes are not seen in all patients. At present, there is no definite evidence that regular long-term bronchodilator therapy influences the natural history of COPD either favourably or adversely. 1 Most studies suggest that short-acting beta 2 agonists and the anticholinergic agent ipratropium work equally as well in patients with COPD. 2 If occasional and low doses are sufficient a beta 2 agonist should be prescribed first because of its more rapid onset of action 2 and lower cost. 1 If there is insufficient control of symptoms with beta 2 agonists or the patient develops side effects such as tremor, you can add or substitute regular ipratropium via a metered dose inhaler. 3 There is no role for long-acting beta 2 agonists except where there is co-existing asthma. Theophylline should be considered only for patients in whom other treatment has failed to control symptoms adequately; careful dosing and monitoring for both therapeutic efficacy and toxicity is required. Corticosteroids In contrast to their value in asthma management, the role of corticosteroids in the routine treatment of COPD is less clear. 3 In the short-term, a small proportion of patients with COPD benefit from corticosteroids: a meta-analysis found that stable COPD patients receiving oral corticosteroids had a 20% or greater improvement in baseline FEV 1 approximately 10% more often than similar patients receiving placebo. 5 It is not clear from the evidence whether benefits are sustained over the long-term. It is therefore reasonable to consider a short trial of corticosteroids with COPD patients where severity of symptoms has increased or bronchodilators have offered no relief. Lung function, exercise tolerance and symptoms should be objectively compared before and after a trial of corticosteroids. Corticosteroids should be withdrawn if objective benefit cannot be demonstrated. 1 Traditionally oral corticosteroids are used but some guidelines suggest that the initial corticosteroid trial be performed with inhaled corticosteroids as these can be maintained where there is a positive response. 6 Some guidelines suggest a three month trial of micrograms of inhaled corticosteroids to determine responsiveness that is based on evidence of a clear clinical response, an increase in postbronchodilator FEV 1 of 10% predicted and/or an absolute increase in FEV 1 of at least 200mL. 4 There is a small amount of evidence that inhaled corticosteroids may reduce the number of exacerbations but more evidence is needed. Whilst peak expiratory flow can be used to assess response, it should not be relied on in advanced emphysema as it may be only moderately reduced, whilst the FEV 1 is severely affected. 4 General management of exacerbations Suggested management of a COPD exacerbation: Add or increase bronchodilators (ensure correct use and appropriate inhaler device). 2 Give antibiotic when there is increased cough and dyspnoea together with increased sputum volume and/or purulence and/or fever. When indicated, use amoxycillin or doxycycline for 5 to 12 days. 7 Consider a short course of oral corticosteroids if no improvement within 48 hours or if marked wheeze present from the beginning of the exacerbation. 4

3 Give it up the best advice for COPD patients Stopping smoking is the single most important way of affecting outcome in patients at all stages of COPD. It is also the most effective way of preventing COPD and other lung and heart diseases. Dosage 8 Smokers lose FEV 1 at an accelerated rate that cannot be prevented by drug therapy. 2 Smoking cessation in COPD will not result in restoration of lost function, although there may be a small increase in FEV 1 initially 4, but it will slow the rate of deterioration of FEV 1. 2 Smoking is both a behavioural problem and a chemical addiction so the most effective cessation strategies address both problems. 6 Medical practitioners have an important role in advising patients to quit and in providing information and ongoing support. Additional help on behavioural strategies for quitting or for patient information is available from the Quit line: NRT can help Evidence has shown that nicotine replacement therapy (NRT) is the most effective pharmacotherapy to help smokers quit. Transdermal NRT is easier to use and better tolerated than nicotine gum. Although there have been concerns over the safety of nicotine patches in patients with cardiovascular disease, it appears they are less likely to cause coronary ischaemia or thrombosis than smoking. (See product information for other contraindications.) When used correctly, nicotine patches provide continuous nicotine blood levels which, with the 21 mg patch, are approximately half those achieved from smoking a pack of cigarettes per day. Transdermal patches which supply nicotine over 16 or 24 hours are considered to be equally effective. For smokers of more than 15 cigarettes a day Nicotine 21mg/24 hour patch initially, changing to the nicotine 14mg/24 hour patch after 4 to 6 weeks. OR Nicotine 15mg/16 hour patch initially, changing to the nicotine 10mg/16 hour patch after 4 to 6 weeks (apply in the morning and remove at bedtime). For smokers of cigarettes a day, or who weigh less than 45 kilograms Nicotine 14mg/24 hour patch initially, changing to the nicotine 7mg/24 hour patch after 4 to 6 weeks. OR Nicotine 10mg/16 hour patch initially, changing to the nicotine 5mg/16 hour patch after 4 to 6 weeks (apply in the morning and remove at bedtime). For some members of this group, however, smoking cessation without NRT may be possible. For smokers of less than 10 cigarettes a day Try simple behavioural techniques; if these fail use NRT dose as for those who smoke cigarettes. For more information, see Therapeutic Guidelines Cardiovascular 1999 or Therapeutic Guidelines Respiratory Products Formulation Strength Brands available nicotine patches 15mg/16 hours Nicorette Patch 10mg/16 hours 5mg/16 hours 21mg/24 hours Nicabate 21, Nicotinell 30 14mg/24 hours Nicabate 14, Nicotinell 20 7mg/24 hours Nicabate 7, Nicotinell 10 nicotine chewing gum 2mg per piece 4mg per piece Nicorette Chewing Tablets, Nicotinell Chewing Gum

4 Your views on Case Study 2 Case Study 2 concerned the 6 year old with bilateral acute otitis media. Those who participated in the case study will receive detailed feedback and expert commentary from Doris Young, Professor of General Practice, and Dr John Ferguson, Clinical Microbiologist. Here is a snapshot of the aggregated responses: Most respondents would not do any further investigations at this time beyond a thorough clinical examination. Five people say they would perform audiometry and tympanometry after the acute episode had resolved. 92% of respondents would prescribe an antibiotic and a large majority chose amoxycillin as their first choice. The most frequently prescribed dose of amoxycillin was 250mg three times daily. This is in accordance with dose recommendations that children >20kg should receive a dose equivalent to the adult dose. Most respondents (53%) who chose to use an antibiotic would treat the patient for 6-7 days. About a third of respondents said they would prescribe paracetamol. This underestimates the number of doctors who would recommend use of paracetamol however. Another 54% noted that they would advise the parent to administer paracetamol or would advise about adequate analgesia. Helping your patients quit smoking Consider the following when assisting your patients to quit: 4 Most smokers need preparation to quit. The smoker should be given information about the adverse effects of smoking and the benefits of quitting. Smokers with a high nicotine dependence need nicotine replacement therapy initially as well as behavioural therapy. The smoker should understand why the smoking habit is pleasurable. The smoker should be assisted to develop acceptable alternatives to smoking behaviour. Behaviour modification requires substitution behaviour along with positive feedback from a wide variety of sources. A trusted medical practitioner is the most effective initial source of information and advice. Exercise and education assist patients with COPD Studies have shown that respiratory rehabilitation programs can add to the quality of life of patients with COPD. Respiratory rehabilitation programs have become increasingly available in Australia in recent years. There are programs in each State capital city. Integrated programs including education, exercise, behaviour modification and support are more effective than individual components used separately. A meta-analysis of 65 studies found that comprehensive pulmonary rehabilitation programs can improve multiple measures of functioning and well-being of adults with COPD. The accuracy in performing psychomotor skills (eg inhaler use) can be improved through education; and relaxation has been shown to reduce psychological distress and dyspnoea. 10 A Cochrane review 11 of the components of a respiratory rehabilitation program found that, while the real treatment effects of most interventions could not be estimated, exercise training should be a mandatory component of any rehabilitation program that seeks to improve functional exercise capacity and health-related quality of life. High intensity training may provide significant extra benefit on muscle strength and cardiovascular functioning. Behavioural training and psychosocial care will reduce breathlessness for a short time and may promote patient compliance. For information about respiratory rehabilitation programs and support services, contact the Australian Lung Foundation on , or visit their web site at Or contact your local Area Health Service or major referral hospital.

5 This doesn t go with that The following groups of medications should be avoided, when possible, in patients with COPD: respiratory depressants such as sedatives (particularly benzodiazepines*) and narcotics 4 this is particularly important in patients with hypercapnia receiving oxygen therapy 9 beta-blockers, including eye drop formulations, which may cause bronchospasm. Other drug therapies may also have respiratory effects. For example: Cough in COPD patients who are taking angiotensin converting enzyme inhibitors (ACEI) may be caused by either their COPD or the ACEI. Angiotensin II receptor antagonists may also cause cough. Other drugs may cause pulmonary toxicity eg amiodarone. *The non-benzodiazepine buspirone (Buspar ) may help relieve panicky breathlessness without the respiratory depressant effects of benzodiazepines. 6 Recommended vaccinations Patients of all ages with COPD should receive an influenza vaccination every year in autumn and a pneumococcal vaccination every five years, according to the NHMRC s Australian Immunisation Handbook. The vaccines can be given at the same visit. Available products Bronchodilators Short-acting beta 2 agonists salbutamol (Airomir, Asmol, Respax, Respolin, Ventolin ) terbutaline (Bricanyl ) Long-acting beta 2 agonists eformoterol (Foradile, Oxis ) salmeterol (Optrol, Serevent ) Anticholinergic bronchodilators ipratropium (Atrovent, Ipratrin ) Theophylline (Austyn, Nuelin, Theo-Dur ) Inhaled corticosteroids beclomethasone (Becloforte, Becotide, Respocort ) budesonide (Pulmicort ) fluticasone (Flixotide ) Contributing authors Drug and Therapeutics Information Service (DATIS) Adelaide, SA Reviewers A/Prof Don Campbell, Head Clinical Epidemiology & Health Service Evaluation Unit, Royal Melbourne Hospital Dr Nick Carr, General Practitioner Prof Ric Day, Clinical Pharmacology, St Vincent s Hospital, NSW Ms Jan Donovan, Consumer Dr John Dowden, Australian Prescriber Dr Gary Franks, General Practitioner Dr Peter Frith, Director Respiratory Section, Repatriation General Hospital, SA Ms Mary Hemming, Therapeutic Guidelines Ltd Prof John Murtagh, Royal Australian College of General Practitioners Ms Susan Parker, AstraZeneca Ms Simone Rossi, Australian Medicines Handbook Prof Richard Ruffin, Respiratory Physician, Head of Medicine, Queen Elizabeth Campus, SA References 1. Jenkins CR, Mitchell CA. Med J Aust 1997;167(5) Anonymous. BTS Guidelines for the management of chronic obstructive pulmonary disease. Thorax 1997; 52 (suppl5):s1-s Anonymous. Standards for the diagnosis and care of patients with chronic obstructive pulmonary disease. Am J Respir Crit Care Med 1995; 152(5pt2):S77-S Siafakas NM, Vermeire P, Pride NB, Paoletti P, Gibson J, Howard P, et al. Eur Respir J 1995; 8(8): Callahan CM, Dittus RS, Katz BP. Ann Intern Med 1991; 114(3): Jenkins C, Mitchell C, Irving L, Frith P, Young I. Mod Med Aust 1995; 38(5): Writing Group for Therapeutic Guidelines: Antibiotic. Therapeutic Guidelines: Antibiotic 10th ed. Melbourne, Therapeutic Guidelines Ltd; N P S National Prescribing Service Limited 8. Writing Group for Therapeutic Guidelines: Cardiovascular. Therapeutic Guidelines: Cardiovascular 3rd edition. Melbourne, Therapeutic Guidelines Ltd; Young IH, Crockett AJ, McDonald CF. Med J Aust 1998; 168(1): Devine EC, Pearcy J. Patient Education and Counseling 29(2): pp In: The Cochrane Library. 11. Lacasse Y, Guyatt GH, Goldstein RS. Chest 111(4): pp In: The Cochrane Library. Our goal To improve health outcomes for Australians through prescribing that is : safe effective cost-effective. Our programs To enable prescribers to make the best prescribing decisions for their patients, the NPS provides: information education support and other resources. 9 Leichhardt St Darlinghurst NSW 2010 Phone: l Fax: l sjackson@zip.com.au