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This preventable chronic lung disease is the fifth leading cause of mortality in Australia . management , when appropriate , to ensure the patient ’ s symptoms and psychosocial issues are optimally managed at all times .
Development of care plans
Patient education on disease processes , inhalers and action plans supports self-management of chronic disease and exacerbations . Action plans are tailored to each individual to direct escalation of inhalers , early commencement of oral steroids and / or antibiotics and to seek medical review early .
Management of exacerbations
A COPD exacerbation is defined as worsening symptoms of dyspnoea , cough and / or sputum beyond the normal day-to-day variation , with an acute onset that warrants additional treatment . Exacerbations are important to diagnose and treat as they carry a 25 % 12-month mortality rate . 1 When exacerbations are diagnosed and treated early , hospital admissions and COPD progression may be prevented .
Triggers include infections ( viral or bacterial ), heart failure , air pollution and psychosocial stressors . It is important to exclude other causes , such as cardiac events , pulmonary emboli or pneumothorax . Management includes an increase in short-acting bronchodilators via a metered-dose inhaler with a spacer . Oral steroids ( prednisolone 50mg for 3-5 days ) assist with the reduction of airway inflammation , severity and time to recovery . Oral antibiotics ( amoxycillin or doxycycline ) should be considered for increased sputum volume , purulence or fever . Oxygen supplementation with an oxygen saturation target of 88-92 % and non-invasive ventilation should be initiated in hospital for hypoxaemia or hypercapnic ( type 2 ) respiratory failure , respectively .
What is on the horizon for COPD diagnosis and management ?
The Global Initiative for Chronic Obstructive Lung Disease ( GOLD ) international COPD strategy and The Lancet Commission
on COPD have outlined evolving strategies — new or in development — for COPD diagnosis and management . 4 , 5
PREVENTION OF MULTIPLE RISK FACTORS There are multiple interacting risk factors for the development of COPD . The proposed aetiological classifications of COPD are genetic , early-life events , respiratory infections , tobacco exposure and other environmental exposures . 4 COPD disproportionately affects the socioeconomically disadvantaged . Globally , about half of people who
develop COPD have never smoked . 2 Suboptimal lung growth during development is an important risk factor that is related to childhood respiratory infections , poor socioeconomic conditions , air pollution and other factors . Risk factors for developing disease can be reduced by public health strategies to ban smoking , maintain clean air and reduce socioeconomic discrepancies .
EARLY DIAGNOSIS As there is currently no disease-modifying treatment , emphasis is placed on early identification and diagnosis of COPD . This can include mild obstruction on spirometry at earlier ages ( eg , young adults ) or early radiological changes ( eg , emphysema on CT chest ) while asymptomatic . Early radiological evidence of emphysema is associated with more rapid decline in spirometry , development of lung cancer and increased mortality . Therefore , with the push to introduce CT screening for lung cancer in Australia , there is much interest in the use of CT chest scans not just for nodule detection but also for identifying emphysema and other radiological abnormalities , such as bronchiectasis .
Current COPD diagnostic criteria unfortunately only capture individuals with irreversible lung damage . The hopes are to implement a more inclusive definition and diagnostic criteria , for mild disease to be more effectively identified and for therapies to be commenced early .
Smoking remains the most significant risk factor for COPD development in high-income countries .
BETTER SELECTION OF INHALED MEDICINES There are at least 33 different inhaled therapies available for COPD . These devices differ in size , steps for preparation , force required to load or actuate , delivery time , inspiratory manoeuvres and device maintenance . Therefore , it is pertinent to select the optimal inhaler for compatibility with dexterity , inspiratory force , duration and patient preference of device . Metered-dose inhalers and soft-mist inhalers require a slow and deep co-ordinated inspiration to trigger the device . Dry-powder inhalers require more forceful inspiration but have lower carbon emissions when considering planetary impact . 6 Reduction in inhaler burden and patient preference have also been shown to improve adherence .
NEWER INTERVENTIONS Bronchoscopic and surgical therapies for lung volume reduction reduce hyperinflation and gas trapping to improve lung function , exercise capacity and quality of life . These continue to be developed .
Sputum cell counts may improve phenotyping of the COPD inflammatory profile , with recent clinical trials demonstrating the biologic dupilumab , used for severe asthma , to be efficacious in COPD patients with type 2 inflammation . 7 Current phase III clinical trials with the aim of inducing regeneration of normal epithelium include nitrogen cryospray , rheoplasty and lung denervation . Suboptimal nutritional status is associated with reduced lung growth and accelerated decline . Vitamin D sufficiency is associated with reduction in exacerbation frequency , vitamin C and E with improvement of lung function and vitamin A for the regulation of early lung development . 5
BETTER CHARACTERISATION OF EXACERBATIONS A more objective definition of an exacerbation , subtyping and streamlined workup would assist in early detection and management . Included in such workup should be the exclusion of common comorbidities or mimics , including acute cardiac ischaemia , congestive heart failure or pulmonary embolism . There is increasing evidence that low CRP or procalcitonin levels may indicate that antibiotic therapy is not required . 4
CLINICAL TRIALS Ultimately , even with changes to the diagnostic criteria of COPD and definition of an exacerbation , the overall management will not change significantly until more effective therapies are developed . One of the main limitations in successful clinical trials for COPD therapies is the heterogeneity of the disease , resulting in the outcomes of most trials not capturing an overall improvement in this diverse group . Phenotyping and the use of other objective measures of lung function and disease progression can help with this barrier .
This is an exciting time in the field of COPD , with the shifting focus from largely symptomatic therapy to disease-modifying therapy , personalised medicine and elimination of COPD through prevention . 4
References on request from kate . kelso @ adg . com . au
Online resources
• COPD-X Guidelines copdx . org . au
• GOLD COPD strategy goldcopd . org
• Lung Foundation Australia Stepwise Management of Stable COPD lungfoundation . com . au / resources / stepwisemanagement-of-stable-copd
• The Lancet COPD Commission thelancet . com / journals / lancet / article / PIIS0140-6736 ( 22 ) 01273- 9 / fulltext