The overall objective of Lung Health Study III is to determine the long-term effects of smoking cessation and continued smoking on heart and lung illnesses and the rate of decline of FEV1 in men and women with early COPD. The participants in this study are drawn from the 5,887 participants randomized into Lung Health Study I.

The follow-up of the LHS I participants will be extended from the original five years to a total of 12 to 15 years in order to:

• Determine if the LHS I smoking intervention program significantly reduces the incidence of heart and lung illnesses
• Determine if the beneficial effects of the LHS I smoking intervention program on lung function and rate of decline of FEV1 persist for 10 to 12 years after the program
• Determine how the size of a decline in FEV1 increases the chance for respiratory, cardiovascular and other illnesses
• Identify factors like gender and weight gain/loss which change the rate of decline of FEV1 and how they interact with changes in smoking habits
• Determine whether the improvement in lung function and reduction in respiratory problems associated with smoking cessation result in improved health and quality of life

The Lung Health Studies I, II and III are multi-center clinical trials sponsored by the Division of Lung Diseases of the National Heart, Lung, and Blood Institute.