Symptoms of chronic bronchitis, haemostatic factors, and coronary heart disease risk

Positive association has been suggested between a variety of infections and coronary heart disease. Disturbances in blood coagulation system may form a link between infections and coronary heart disease. The aim of this study was to analyze whether chronic bronchitis, defined by the occurrence of symptoms, is associated with selected haemostatic factors in a cross-sectional population study of 2379 Finnish men and women aged between 45 and 64 years. Plasma fibrinogen level was significantly higher, 3.70 versus 3.35 g/l (P < 0.001) in men and 3.64 versus 3.44 g/l (P < 0.001) in women, among subjects with symptoms of chronic bronchitis than among those without symptoms. The association was independent of age, smoking, body mass index, physical exercise, and alcohol consumption. Also plasminogen was higher among men with symptoms than among those without but the difference disappeared after adjustment for age and smoking. Factor VII coagulant activity and factor VII antigen level did not differ between subjects with and without symptoms. Thus, fibrinogen may be associated with a possible mechanism to link chronic bronchitis to coronary heart disease risk, even though the causality of the association cannot be verified in a cross-sectional study.