Treadmill exercise testing in asymptomatic chronic smokers to detect latent coronary heart disease

The treadmill exercise test has been performed in 50 chronic smokers and 50 non-smokers (93 males and 7 females) who were not having any clinical or electrocardiographic manifestation of ischemic heart disease. The test was positive in 18% chronic smokers and 4% in non-smokers, the chances of positivity of stress test was 4-5 times greater in chronic smokers than in non-smokers. The duration of smoking and number of/cigarettes/bidis smoked per day were directly proportional to the incidence of a positive stress test. There was no significant difference in the incidence of a positive exercise test amongst purely cigarette smokers (17.64%), purely bidi smoker, (16.16%), and in both bidi and cigarette smokers (20%). The study, therefore, suggests that chronic heavy smoking is more frequently associated with asymptomatic ischemic heart disease, as compared to non-smokers and stress testing of persons with coronary risk factors important for detection of latent IHD.