Supported by the National Heart, Lung, and Blood Institute (NHLBI), the study followed more than 5,300 middle-aged smokers for five years. All participants had mild or moderate chronic obstructive pulmonary disease (COPD). In the first year after quitting, women's lung function improved more than twice that of the men's. Among those who quit, improved lung function remained greater for women than for men throughout the study, although the differences between the genders narrowed over time. The decline in lung function in those who continued to smoke was on average similar for men and women.
Cigarette smoking is a leading cause of COPD, a slowly progressive disease of the lung that is characterized by a gradual loss of lung function. COPD is the fourth most common and the most rapidly increasing cause of death in the United States. Emphysema, chronic bronchitis, chronic obstructive bronchitis, or a combination of emphysema and chronic bronchitis are forms of COPD.
NHLBI is part of the National Institutes of Health (NIH), the Federal Government's primary agency for biomedical and behavioral research. NIH is a component of the U.S. Department of Health and Human Services. Information about COPD and other lung diseases, as well as cardiovascular, blood, and sleep disorders are available online at www.nhlbi.nih.gov .
American Journal of Epidemiology