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What is Chronic Obstructive Pulmonary Disease?

Chronic Obstructive Pulmonary Disease (COPD) is a chronic respiratory disease characterized by chronic inflammation of the bronchi and decreased lung capacity, causing difficulty breathing (dyspnea) especially during exertion.

Understanding COPD

People with chronic obstructive pulmonary disease have inflammation of the airways, bronchi, and lung tissue in particular. COPD is usually caused by cigarette smoke or inhalation of harmful compounds. This inflammation leads to a narrowing of the airways, preventing air from passing through. 

Depending on the stage of the disease, the pulmonary alveoli are eventually destroyed: this is called pulmonary emphysema (or emphysema). Emphysema is, therefore, defined by the destruction of the pulmonary alveoli and disappearance of the gas exchange that normally occurs there, resulting in the reduction of the patient's lung capacity. As a result, the risk of stroke and myocardial infarction doubles. 

According to the World Health Organization, COPD is the third leading cause of death in the world, after ischemic heart disease and stroke.

All around the world 210 millions of people

affect 10% of the population age 40 to 60

COPD symptoms

The main symptom of chronic obstructive pulmonary disease is shortness of breath (dyspnea) on exertion, followed by chronic cough and sputum production.

These nonspecific symptoms of COPD resemble those of chronic bronchitis, leading to a late diagnosis of the disease. 

Episodes of exacerbation and prolonged worsening of symptoms such as shortness of breath (including at rest), increased coughing with or without sputum, may be due to an infection of the lower respiratory tract (lungs) and are more common in the advanced stages of the disease and may lead to to respiratory failure.

The main symptom: shortness of breath on exertion

Do you have difficulty with any of these activities?

If you have trouble performing everyday activities like these, especially in the morning, see your doctor.
80% of COPD cases are attributed to smoking.

Other factors can increase the risk of COPD or contribute to its worsening:

  • Passive smoker. Still, a third of people with COPD have never smoked;
  • Air pollution is considered an important aggravating factor, which increases the risk of exacerbation episodes;
  • Frequent lower respiratory tract infections in childhood may be responsible for the occurrence of COPD in adulthood;
  • Exposure to dust and chemicals, mainly related to certain professional activities, is responsible for 15% of COPD cases;
  • Most of the time, COPD leads to decreased physical activity and reduced exercise tolerance. This decline in activity is an aggravating factor for the disease, causing the well-known phenomenon of the deconditioning spiral;
  • As with any multifactorial disease, there is also a genetic component: a British study showed that smokers who have in their family circle (first degree of relationship) a person who developed a severe case of COPD before age 55 are three times more likely to develop airway obstruction than smokers without a family history. This study suggests that genetic factors that interact with tobacco consumption influence the onset of the disease.


1. Global Initiative for Chronic Obstructive Lung Disease. Global Strategy for the diagnosis management and prevention of chronic obstructive pulmonary disease. Mis à jour in 2017; disponible sur…;…

2. ERS. Chronic obstructive pulmonary disease in: European lung white book. Available on…;…


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5 .WHO. Bronchopneumopathie chronic obstructive (BPCO). Aide mémoire N°315, October 2014. Available ; see 11/05/2014