What is COPD?
Chronic Obstructive Pulmonary Disease (COPD) is a progressive incurable lung disease characterised by an irreversible obstruction of airflow. The term COPD includes lung emphysema and chronic bronchitis, and is one of the most common respiratory diseases, affecting mainly people over the age of 40. 1 COPD is a major cause of chronic morbidity and mortality throughout the world.
However, COPD isn’t just a problem of the lungs but affects the whole body, causing a progressive degenerative cycle of decline in physical capacity through loss of muscle mass (muscle wasting) and loss of muscle strength. Current international treatment guidelines state that treatment should include both symptom relief to ease breathing, but also exercise intervention and/or pulmonary rehabilitation, to improve physical performance and quality of life. 2
About COPD
The Global initiative for Chronic Obstructive Pulmonary Disease (GOLD) classifies COPD progression into several stages to aid diagnosis. The classification levels are based on assessing the forced expiratory volume after 1 second (FEV1) against the predicted FEV1 values for the patient’s age.
The COPD stages may be used to guide the most appropriate treatment at each stage: 2
Stage I: Mild COPD (FEV1 ≥ 80% predicted)
The patient will be experiencing mild airflow limitation and usually also chronic cough and sputum production.
Stage II: Moderate COPD (50% ≥ FEV1 ≥ 80% predicted)
There is worsening airflow limitation and symptom progression experienced, such as shortness of breath during mild exercise. Acute exacerbations are also seen.
Stage III: Severe COPD (30% ≥ FEV1 ≥ 50% predicted)
Further worsening of airflow limitation, greater shortness of breath, reduced exercise capacity, fatigue and repeated exacerbations that almost always have an impact on quality of life.
Stage IV: Very Severe COPD (30% ≥ FEV1 ≥ 50% predicted)
The patient presents with severe airflow limitation and with respiratory failure or clinical signs of right heart failure. At this stage exacerbations may be life-threatening and quality of life is significantly impaired. 2
However GOLD classification alone often doesn’t represent the true burden of COPD on the patient and their level of complaints. A GOLD 4 patient may have fewer complaints than another patient with a GOLD 2 classification. The severity of the symptoms is also affected by the patient’s mental and physical state.
References
1. NHS Clinical Knowledge Summaries: Chronic Obstructive Pulmonary Disease. Available at https://www.cks.library.nhs.uk/patient_information_leaflet/chronic_obstructive_pulmonary_disease [Accessed August 2009]
2. Global Initiative for Chronic Obstructive Lung Disease. Global strategy for the diagnosis, management and prevention of chronic obstructive pulmonary disease. Available at http://www.goldcopd.com/Guidelineitem.asp?l1=2&l2=1&intId=2003 [Accessed August 2009]