Background: Our aim was to investigate the association between respiratory symptoms and mortality from ischaemic heart disease (IHD) and stroke in a population during 30 years follow-up.
Methods: In 1972, 19998 persons aged 15-70 years, living in Oslo, were selected for a respiratory survey (response 89%). Respiratory symptoms were divided into four groups and given a score. The association between respiratory symptoms and mortality from IHD and stroke were investigated separately for men and women, with adjustment for age, occupational exposure to air pollution and smoking habits.
Results: IHD accounted for 1572 and stroke for 653 of all deaths. The adjusted hazard ratio (HR) for mortality from IHD in men varied from 1.3 (95% confidence interval, 1.1-1.5) to 3.0 (2.3-3.8) and in women from 1.2 (1.0-1.5) to 1.9 (1.4-2.5) for cough symptoms and severe dyspnoea, respectively. Symptom score predicted death from IHD, in a dose-response manner. The HR for mortality from stroke varied from 1.0 to 2.3 in men and from 1.1 to 1.5 in women for the symptom groups, but was significant only among men reporting severe dyspnoea and among women reporting moderate dyspnoea. For all respiratory symptoms, the excess risk for cardiovascular mortality decreased during follow-up, but IHD-mortality was still significantly increased the last decade.
Conclusion: We found a significant, positive association between respiratory symptoms and 30-year mortality from IHD. The positive association was weaker between respiratory symptoms and long-term mortality from stroke.