OBSERVATIONS ON THE INDIVIDUAL EFFECTS OF SMOKING ON THE BLOOD PRESSURE, HEART RATE, STROKE VOLUME AND CARDIAC OUTPUT OF HEALTHY YOUNG ADULTS

Abstract

Effects of smoking upon the systolic pressure, diastolic pressure, pulse pressure, heart rate, stroke volume (as determined by the ballistocardio-graph), cardiac output and cardiac index were measured in 113 healthy medical students. Statistically significant changes occurred in all measurements following the smoking of one cigarette. The direction and degree of change after smoking varied greatly from subject to subject, so that striking individual differences in circulatory patterns were found. Groups of individuals selected on the basis of similar changes in a single circulatory deter-minant had characteristic over-all patterns of change after smoking differing from those of other groups. The circulatory patterns of certain subgroups were compared. Among the more striking differences found were those associated with family history. Subjects with parental hypertension, whose control cardiac output and cardiac index were large to begin with, showed more than twice as great an increase in cardiac output and cardiac index as did subjects with negative parents. Likwise, subjects with a parental history of coronary artery disease showed very little increase in cardiac output and cardiac index, in contrast to subjects with negative parents.