Antihypertensive monotherapy and stress-induced changes in physiological activity

The effects of two types of laboratory stressors, a structured interview and the cold pressor test, on blood pressure (BP) and heart rate (HR) were studied in normotensive individuals (n = 16), unmedicated hypertensive patients (n = 12), and medicated hypertensive patients (n = 46). Fifteen patients were in the bisoprolol group, 16 patients were in the enalapril group, and 15 patients were in the nitrendipine group. Concurrent physiologic measures, finger pulse volume (FPV), electrodermal activity, and respiratory frequency (RF), were also used to evaluate the level of stress reached by the subjects during and after the tasks. No significant differences were evident between the different treatments in BP and other physiologic responses to stressors. Patients receiving bisoprolol maintained lower HR and systolic BP values, but these differences were not related to the reaction to the stressors. No significant differences were noted in diastolic BP (DBP) between the different groups. The highest physiologic responses were obtained during the structured interview. Antihypertensive monotherapy does not attenuate cardiovascular reactions induced by acute stress in controlled laboratory conditions. In laboratory studies of the relationships between stress and hypertension, it is important that social stressors be used and that physiologic rather than cardiovascular measures of stress be recorded.