COPD can lead to difficulty in breathing, cough, frequent respiratory infections and more. Smoking is one of the leading causes of COPD. Read here to know causes of COPD from the expert and the importance of prevention.
Chronic obstructive pulmonary disease (COPD), or the deposition of black tar in the lungs, is different from asthma. Asthma is predominantly an allergic disease caused by a combination of genetic and environmental factors and is characterised by variable and recurrent symptoms of wheeze, cough, chest tightness, shortness of breath while the patient may be asymptomatic during allergy-free periods in the early part of the disease. It is predominantly associated with nasal symptoms as well, which characterises its allergic nature.
COPD, on the other hand, is characterised by a narrowing of airways along with the destruction of lung tissue. Patients usually complain of gradually progressive shortness of breath and cough with sputum production. Other symptoms that may be present are chest tightness and wheezing. In the advanced stage of the disease, the patient may have leg swelling, which is due to increased pressure on the right heart (increased obstruction with increased lung size compresses blood vessels coming from the right heart) preventing systemic drainage of blood to the heart and increasing swelling, especially in the legs.
Tobacco smoke is the most common cause of COPD worldwide. In India, among tobacco use, smoking is one of the major cause of deaths and diseases like COPD, lung cancers and others and accounts for millions of such cases. Other causes of COPD are occupational exposure and air pollution. Among all patients with COPD, about 85-90% of patients come with a history of smoking or are smokers. Passive smoking or second-hand smoke is also the cause of COPD, especially among non-smokers.