Chronic Airways Disease

Abstract

Cigarette smoking is undoubtedly the most important causative factor in COAD and is largely responsible for the characteristic decline in lung function observed in smokers. Atmospheric pollution, industrial or domestic, and inhaled dusts, act at least additively with cigarette smoking and clinically tend to show their major effects in smokers. Childhood lower respiratory infections probably play a part in the bronchitic element of airways obstruction and may be particularly important in developing countries where such infections are more common and less well controlled, but the evidence suggests that infection is not an important cause of emphysema. Apart from the clear evidence of enhanced susceptibility to tobacco smoke, and consequent premature emphysema, in those with homozygous alpha-antitrypsin deficiency, genetic predisposition is of doubtful importance, though a possible atopic component is again under examination.

Multiple factors determine whether or not a person, often a child, will start smoking and, similarly, whether or not someone who already smokes will quit. Knowledge of the factors that contribute to the "smoking behavior complex" have led to some well-established principles of smoking control that, when applied on a national level in a comprehensive and continuous manner, are effective in reducing the number of people who smoke.