Maladies respiratoires chroniques et tabagisme

Abstract

Chronic respiratory diseases related to tabagism Chronic obstructive lung diseases (COPD) — including chronic bronchitis and emphysema — are an important and increasing public health problem, in which cigarette smoking has been identified as the main responsible factor. Clinical and epidemiological investigations have indicated a strong dose-response relation between COPD and the number of cigarettes smoked per day, the earliness of smoking initiation and the depth of smoke inhalation. In addition, passive inhalation of tobacco smoke may have adverse effects on the respiratory function in children and adolescents, particularly in asthmatics. Experimental studies have demonstrated that tobacco smoke induced inflammatory changes in bronchial mucosa, with ciliary dysfunction and excessive mucus secretion, favouring bacterial colonization and bronchial infection. In the lower respiratory tract of smokers, alveolar macrophages demonstrate many metabolic and functional alterations, with increase in superoxide anion production, neutrophil chemotactic activity and protease secretion, leading to an imbalance between proteases, especially elastase, and alpha 1 protease inhibitor. These changes in alveolar macrophage activities result in alveolar wall damage and enlargement of the distal air spaces. Further research is needed to identify the effects of tobacco smoke components on the respiratory tract, and to evaluate preventive approaches.