C2. Diagnosis

C2.1 History

Consider COPD in all smokers and ex-smokers over the age of 35 years (Fletcher 1977) [evidence level II].

The main symptoms of COPD are breathlessness, cough and sputum production. Patients often attribute breath­lessness to ageing or lack of fitness. A persistent cough, typically worse in the mornings with mucoid sputum, is common in smokers. Other symptoms such as chest tight­ness, wheezing and airway irritability are common (Thompson 1992). Further, many people with COPD have low levels of physical activity and demonstrate reduced exercise tolerance on formal testing (Watz 2014, Cote 2007b). People with chronic cough and sputum are at increased risk of exacerbation (Burgel 2009) [evidence level III-2]. Exacerbations, usually infective, occur from time to time and may lead to a sharp deterioration in coping ability. Fatigue, poor appetite and weight loss are more common in advanced disease.

The effect of breathlessness on daily activities can be quantified easily in clinical practice using the Modified Medical Research Council (mMRC) Dyspnoea Scale (Celli 2004, Fletcher 1960) (see Box 3).

Box 3: Modified Medical Research Council (mMRC) Dyspnoea Scale for grading the severity of breathlessness during daily activities 
Grade Symptom complex
0 I only get breathless with strenuous exercise
1 I get short of breath when hurrying on level ground or walking up a slight hill
2 On level ground, I walk slower than people of the same age because of breathlessness, or I have to stop for breath when walking at my own pace on the level
3 I stop for breath after walking about 100 metres or after a few minutes on level ground
4 I am too breathless to leave the house or I am breathless when dressing or undressing

The COPD assessment test (CAT) (Jones 2009) is relatively short easily scored and provides an alternative to approximately 17 other reported and longer questionnaires such as the SGRO and the CRQ. It may provide useful information when taking a history from patients. The CAT quantifies the impact COPD has on a patient’s wellbeing and daily life, with the aim of facilitating communication between healthcare professionals and patients. The test is comprised of eight questions pertaining to cough, sputum, chest tightness, exercise tolerance, ability to perform activities of daily living, confidence in leaving the home, sleep and energy levels. Each question is scored on a 6-point scale (0 to 5) yielding a total possible score of 40 for the questionnaire. The total CAT score provides a broad clinical picture of the impact of COPD on an individual patient with scores of >30, 21-30, 10-20 and <10 corresponding to very high, high, moderate and low impact respectively. A total score of 5 is the upper limit of normal in a healthy non-smoker (Jones 2011b). A systematic review (Gupta 2014) that included 36 studies carried out in 32 countries reported the CAT to be reliable, valid and responsive as a HRQoL instrument.  However, the minimum clinically important difference in the total CAT score is unclear.The CAT is freely available in many languages (see http://www.catestonline.org/english/index.htm). It is easy and quick to complete, and score. A meta-analysis of eight studies of the CAT questionnaire demonstrates moderately strong predictive values for aspects of COPD including a valid diagnosis, likelihood of exacerbations, depression, lung function and mortality (Karloh 2016).