Lung function, respiratory symptoms, and mortality: Results from the Busselton Health Study

PURPOSE: This study examines the association between lung function [percent age predicted FEV1 (forced expiratory volume in 1 s)] and respiratory sympt oms (asthma, bronchitis, wheeze, dyspnea) and mortality from all causes; co ronary heart disease, stroke, cancer, and respiratory disease in a cohort o f 2100 men and 2177 women in the Busselton Health Study followed for 20-26 years for mortality. METHODS: A total of 840 men and 637 women died during the follow-up period, and Cox proportional hazards regression was used to assess the relationshi ps between risk factors and mortality. RESULTS: Lung function was significantly and independently predictive of mo rtality from all causes, coronary heart disease, cancer, and respiratory di sease in both men and women, and of mortality from stroke in women. There w as evidence that, among men, the association was stronger in current and fo rmer smokers as compared to those who never smoked. After adjustment for ag e, smoking, lung function, coronary heart disease, blood pressure, treatmen t for hypertension, total cholesterol, body mass index, and alcohol consump tion, dyspnea was significantly related to total mortality in men and women and to respiratory disease mortality in men, and asthma was significantly related to respiratory disease mortality in women. CONCLUSIONS: Lung function is associated with mortality from many diseases independent of smoking and respiratory symptoms. Although most respiratory symptoms are associated with smoking and lung function, after controlling f or smoking and lung function, only dyspnea is associated with mortality fro m nonrespiratory causes. (C) 1999 Elsevier Science Inc. All rights reserved .