Family history of hypertension and cardiovascular reactivity to mental stress--effects of stimulus intensity and environment.

Normotensives with hypertensive parents have been reported to exhibit enhanced cardiovascular reactions to mental stress. We have examined the question of why this result was not confirmed in all studies. In addition we have investigated whether appropriate tests can be performed under clinical rather than laboratory conditions. Healthy male subjects were examined. In experiment I, under laboratory conditions, a standard stress test was intensified (n = 30). In experiment II the same test was used in a simplified version which did not require special equipment (n = 19). Blood pressure, heart rate and stroke volume (by impedance cardiography) were measured. In contrast to the results with the standard test, subjects with at least one hypertensive parent exhibited enhanced responses of systolic and diastolic blood pressure and heart rate. We conclude that cardiovascular hyper-reactivity in subjects with hypertensive parents is only apparent using sufficiently intense stimuli. Although less pronounced, these differences can also be observed under clinical conditions.