Chronic obstructive pulmonary disease (COPD) is an umbrella term used to describe a group of lung diseases that cause breathing difficulties; these include emphysema and chronic bronchitis. Emphysema causes damage to the air sacs within the lungs and chronic bronchitis leads to inflammation in the airways. This results in patients having difficulties inhaling and exhaling. COPD is described as progressive and irreversible, therefore drug therapy can only aim to manage the condition, not completely cure it.
COPD is the second most commonly respiratory condition within the UK, with asthma being the most common. According to the British Lung Foundation, it is estimated that 1.2 million people are living with diagnosed COPD, while 2 million people may have undiagnosed COPD. COPD is a large burden on the NHS as it is accountable for over 10% of all hospital admissions and directly costs the NHS around £491million/per year.
The main cause of COPD is smoking. The amount of cigarettes a person smokes and the number of years a person has smoked contributes to a person’s risk of developing COPD. It is important to note that not all patients that smoke develop COPD; this due to a person’s genetics that may modify their risk of developing COPD. Inhaling other harmful substances such as dust, pollution and chemicals may also be contributing factors. COPD is most likely to develop in adults over 35 after long term damage to the lungs. Symptoms however may not present themselves until the COPD is severe.
The main symptoms that characterise COPD include breathlessness, a persistent phlegm cough and recurrent chest infections. Wheezing and tiredness may also be symptoms of COPD. These symptoms may be similar to those of a patient with asthma, which can lead to difficulties distinguishing between the two conditions. Some key clinical differences are that patients with asthma commonly have night time symptoms which are not experienced in COPD patients. Furthermore it is uncommon for patients with asthma to have a chronic productive cough.
The aims of COPD treatment include: managing symptoms, reducing exacerbations, preventing the progression of the disease, increasing exercise tolerance and improving overall health. People with COPD are encouraged to stop smoking if they have not already done so. Nicotine replacement therapy can help people stop smoking with a wide variety of dosage forms such as patches, gum, sprays and inhalers to suit the needs of people’s preferences.
The cornerstone of COPD treatment are bronchodilator inhalers. There are two main types of bronchodilator inhalers: beta-2-agonist and antimuscarinic. They come in either short or long acting formulations. Short acting inhalers are prescribed for people with breathlessness and exercise limitation. Long acting inhalers may be prescribed if a person has persistent breathlessness throughout the day. Inhaled corticosteroids are commonly prescribed for COPD; combined with bronchodilators they improve lung function, reduce the incidence of exacerbations and improve symptoms.