Chronic obstructive pulmonary disease (COPD) is a major and growing health problem throughout the world. In the United States, close to 13 million people were recognized to have the condition in 1986,1 but even this staggering number is probably an underestimate.2 Its annual cost was more than $12 billion in direct and indirect medical expenses in 1990. It is now the fourth leading cause of death in this country, with a mortality of more than 90 000 in 1991.3 These figures do not reveal an equally vital statistic, the great physical limitation and suffering of many of these patients in the last years of their lives. The principal etiologic factor, and by far the most potent one, cigarette smoking, has been known for decades. Moreover, the classic studies of Fletcher et al in the United Kingdom4 and the studies of many others
See also p 1497.
Gross NJ. The Lung Health StudyDisappointment and Triumph. JAMA. 1994;272(19):1539-1541. doi:10.1001/jama.1994.03520190085040