Clinical Knowledge Summaries CKS Chronic obstructive pulmonary disease (COPD) Diagnosis of COPD in primary care Educational slides based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

Key learning points and objectives To be able to: o Recognise people who are at risk of COPD. o Describe the diagnostic features of COPD. o Describe the key features that can help distinguish COPD from asthma. o Describe how to use spirometry to aid in the diagnosis and management of COPD. Based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

Definition Chronic obstructive pulmonary disease (COPD) is: o A treatable and largely preventable lung disease with symptoms such as cough, sputum, and increasing breathlessness. Airflow obstruction is: o Usually progressive, not fully reversible, and does not change markedly over several months. o Associated with abnormal inflammatory response of the lungs, mainly to noxious particles, especially cigarette smoke. Based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

How common is it? Around 3 million people in the UK have COPD. o An additional 2 million have undiagnosed COPD. Prevalence increases with age. o Most people are not diagnosed with COPD until they are 50 years of age or older. A GP practice looking after 7000 people will have around 200 people with COPD (many undiagnosed). COPD is: o The second largest cause of emergency hospital admissions (one in eight). o One of the most expensive inpatient conditions treated by the NHS. Based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

Risk factors Smoking tobacco is the major risk factor for developing COPD (90% of cases are caused by cigarette smoking). o Lower morbidity and mortality rates for pipe and cigar smokers (compared with cigarettes). Other risk factors include: o Occupational exposure — dust, chemicals, noxious gases, and particles. o Air pollution — wood, animal dung, crop residues, and coal. o Genetic causes — homozygous alpha 1 -antitrypsin deficiency (less than 1% of cases). Based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

Prognosis COPD is progressive. Once developed, it cannot be cured. However: o Stopping exposure (e.g. smoking) may slow or halt the progression. In the UK, about 30,000 people die of COPD each year (5% of all deaths). o Mortality from COPD increases with age, severity of disease, and socioeconomic deprivation. Exacerbations of COPD that need hospital admission are associated with an inpatient mortality rate of 3– 4%. o This increases to 11–24% for people who require treatment in an intensive care unit. Based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

Complications COPD is associated with: o Disability and impairment of quality of life. o The person may develop reduced mobility or become increasingly housebound. o Depression and anxiety. o Two of the most common and least treated comorbidities of COPD. o Frequent respiratory infections. o Polycythaemia. o Respiratory failure. Based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

Symptoms of COPD Typical symptoms of COPD include: o Exertional breathlessness. o Chronic cough. o Regular sputum production. o Frequent 'winter bronchitis'. o Wheeze. Other symptoms include: o Weight loss. o Exercise intolerance. o Ankle swelling. o Fatigue. o Chest pain or haemoptysis (uncommon). Based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

Physical signs of COPD The following signs may be present: o Hyperinflated chest. o Wheeze or quiet breath sounds. o Pursed lip breathing. o Use of accessory muscles. o Peripheral oedema. o Cyanosis. o Raised jugular venous pressure. o Cachexia. Based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

What else could it be? Asthma Can be difficult to distinguish from COPD and both conditions may coexist (discussed later). Bronchiectasis Congestive cardiac failure. Lung cancer. Interstitial lung disease (e.g. asbestosis). Bronchopulmonary dysplasia. Anaemia. Obstructive sleep apnoea. Tuberculosis. Based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

Making a diagnosis of COPD There is no single diagnostic test for COPD. A diagnosis of COPD should be considered in people: o Over the age of 35 who have a risk factor (generally smoking) and o Who present with one or more of the following symptoms: Exertional breathlessness. Chronic cough. Regular sputum production. Frequent winter bronchitis. Wheeze. Based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

Making a diagnosis of COPD Consider alternative diagnoses. Arrange a chest X-ray to help exclude other causes. Consider the possibility of alpha 1 -antitrypsin deficiency if: o The person is younger than 40 years of age or has a family history of alpha 1 -antitrypsin deficiency. Based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

Making a diagnosis of COPD Reconsider the diagnosis of COPD (and consider the possibility of asthma) if: o The person has a marked response to drug treatment (e.g. inhaled beta-2 agonist). A marked response includes: o A marked improvement in symptoms, or o Return of forced expiratory volume (FEV 1 ) and FEV 1 /FVC forced vital capacity ratio to normal. Based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

Distinguishing asthma from COPD Consider the possibility of COPD if the person meets all the following criteria – Age older than 35 years. – Presence of a risk factor (for example current smoking, history of smoking, or an occupational exposure). – Presence of typical symptoms such as: Exertional breathlessness. Chronic cough. Wheeze. Regular sputum production. Recurrent chest infections. – Other symptoms that may be present include: Weight loss. Exercise intolerance. Ankle swelling. Fatigue. – Absence of clinical features of asthma In addition, the presence of airflow obstruction must be confirmed by post-bronchodilator spirometry. Based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

Distinguishing clinical features Clinical featuresCOPDAsthma Smoker or ex-smokerNearly allPossibly Age < 35 yearsRareOften Chronic productive coughCommonUncommon BreathlessnessPersistent and productive Variable Night-time waking with breathlessness or wheeze UncommonCommon Significant diurnal or day-to- day variation in symptoms UncommonCommon Based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

Spirometry To confirm the diagnosis of COPD use spirometry: o The ratio of FEV 1 to FVC should be less than 0.7. The slow or relaxed vital capacity (SVC) can be used instead of FVC, if: o The SVC is higher than the FVC, or o The person cannot perform a forced manoeuvre to full exhalation. Spirometry should be done 15–20 minutes after the person has inhaled (via a spacer): o Salbutamol 200 micrograms, or o Terbutaline 500 micrograms. Based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

Spirometry If the FEV 1 is 80% of predicted normal or greater, a diagnosis of COPD should be made only if there are respiratory symptoms (e.g. breathlessness or cough). o Predicted normal values of FEV 1 and FVC: Depend on age, height, and sex. May over diagnose COPD in elderly people and are not applicable in black and Asian populations. Repeat spirometry if: o The person has an exceptionally good response to treatment. Based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

Using spirometry Spirometry measurements are used to: o Measure the severity of airflow obstruction, and o Guide treatment and prognosis. However when used alone spirometry can: o Underestimate the impact of the disease, or o Overestimate it. Based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

Using spirometry Following post-bronchodilator spirometry, airflow obstruction can be classified as: o Stage 1 (mild) - FEV 1 80% of predicted value or higher (symptoms must be present). o Stage 2 (moderate) - FEV 1 50–79% of predicted value. o Stage 3 (severe) - FEV 1 30–49% of predicted value. o Stage 4 (very severe) - FEV 1 less than 30% of predicted value. Based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

Assessing the severity of COPD NICE state that no single measure can adequately assess the true severity of COPD. Assess the severity of COPD according to: o The reduction of FEV 1 on spirometry, o The degree of breathlessness according to the Medical Research Council (MRC) dyspnoea scale, o The BMI - (BMI of less than 20 kg/m 2 is associated with increased mortality) and o Presence of cor pulmonale. Based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

GradeLevel of activity 1Not troubled by breathlessness except during strenuous exercise 2Short of breath when hurrying or walking up a slight hill 3Walks slower than contemporaries on the level because of breathlessness, or has to stop for breath when walking at own pace 4Stops for breath after walking about 100 m or after a few minutes on the level 5Too breathless to leave the house, or breathless when dressing or undressing MRC dyspnoea scale Based on the CKS topic Chronic obstructive pulmonary disease (September 2015), and NICE guidance; Chronic obstructive pulmonary disease: management of chronic obstructive pulmonary disease in adults in primary and secondary care (2010).

Summary Smoking tobacco is the major risk factor for developing COPD (90%). COPD cannot be cured but stopping smoking may slow or halt progression. Asthma can be difficult to distinguish from COPD (both may coexist). o Longitudinal observations (e.g. with peak flow meters) and reversibility testing can help distinguish asthma from COPD. There is no single diagnostic test for COPD. Consider a diagnosis if the person is: o Older than 35 years, has a risk factor (e.g. smoking), and has typical symptoms. Spirometry is used to measure airflow obstruction and help inform management.