The pathogenesis of chronic obstructive pulmonary disease

Cigarette smoking is the main risk factor for the development of chronic ob structive pulmonary disease (COPD). An accelerated rate of lung function de cline that causes clinically significant COPD, however, is present in only a minority of smokers. In addition to the cumulative amount of cigarettes s moked, other environmental and genetic properties contribute to this variab le physiological response. This article reviews the role of airway hyperres ponsiveness, mucus hypersecretion, infection, and proteases in the developm ent of COPD.