The Lung Health Study (LHS)

Objectives:

To determine the effects of Special Care, compared to Usual Care, on rate of decline in pulmonary function in a group of cigarette smokers identified as having mild abnormalities in pulmonary function. In addition, the study sought to determine if participants with chronic obstructive pulmonary disease, who were assigned to inhaled corticosteroids had a lower rate of decline in lung function and lower incidence of respiratory morbidity compared to participants assigned to placebo. Also, the study sought to determine the long-term effects of smoking cessation and continued smoking, on cardiopulmonary morbidity, mortality, and the rate of decline in the one second forced expiratory volume in men and women with early chronic obstructive lung disease who have been followed prospectively for 12 to 15 years. Subjects: Men and women who were cigarette smokers and between the ages of 35 and 60. Results: Participants in the two smoking intervention groups showed significantly smaller declines in FEV1 than did those in the control group. Most of this difference occurred during the first year following entry into the study and was attributable to smoking cessation, with those who achieved sustained smoking cessation experiencing the largest benefit. The small noncumulative benefit associated with use of the active bronchodilator vanished after the bronchodilator was discontinued at the end of the study. The authors concluded that an aggressive smoking intervention program significantly reduced the age-related decline in FEV1 in middle-aged smokers with mild airways obstruction. Use of an inhaled anticholinergic bronchodilator resulted in a relatively small improvement in FEV1 that appeared to be reversed after the drug was discontinued. Use of the bronchodilator did not influence the long-term decline of FEV1. Additionally, the study showed that lung function decline in the patients treated with the inhaled corticosteroid was statistically no different from that in the placebo group. Corticosteroid use did, however, result in 25 percent fewer respiratory symptoms and nearly 50 percent fewer outpatient visits for respiratory problems. However, after three years, bone density in the hip and back was lower in the corticosteroid group.