Chronic obstructive pulmonary disease (COPD) is characterised by chronically poor air flow. Typically, it worsens over time.
The main symptoms include shortness of breath, coughing and sputum production. Most people with chronic bronchitis have
COPD. Tobacco smoking is the most common cause of COPD. A number of other factors, such as air pollution and genetics, play a
smaller role. One of the common sources of air pollution is poorly vented cooking and heating fires in the developing world. Longterm
exposure to these irritants causes an inflammatory response in the lungs, resulting in narrowing of the small airways and
breakdown of the lung tissue, leading to emphysema. Genetic involvement, i.e. alpha-1 antitrypsin deficiency, is now a recognised
cause. The diagnosis is based on poor air flow, as measured by lung function tests. In contrast to asthma, the air flow reduction
does not improve significantly with the administration of a bronchodilator. COPD can be prevented by reducing exposure to
known environmental risk factors. This includes an eﬀort to decrease the rate of smoking and to improve indoor and outdoor air
quality. COPD treatment includes stopping smoking, vaccinations, rehabilitation, and often inhaled bronchodilators and steroids.
Some people may benefit from long-term oxygen therapy or lung transplantation. Increased use of medication and hospitalisation
may be needed in those who have periods of acute worsening. Worldwide, COPD eﬀects 329 million people, or nearly 5% of
the population. In 2013, it resulted in 2.9 million deaths, up from 2.4 million deaths in 1990. The number of deaths is projected
to increase owing to higher smoking rates and an ageing population in many countries. New treatments are also emerging