Journal Articles
Abstract:
Background. This study compared the effects of the cardioselective beta- blocker, atenolol (AT), and the angiotensin-converting enzyme inhibitor, enalapril (EN), on psychophysiologic reactivity to mental stress among hypertensive patients inadequately controlled with a diuretic alone. Methods. Thirty hypertensive subjects (sitting diastolic blood pressure [DBP] between 95 mmHg and 115 mmHg) were randomly assigned to either AT (50-100 mg once daily) or EN (2.5-40 mg once daily), following a 4-week lead-in phase during which subjects were treated with hydrochlorothiazide (HCTZ; 25 mg once daily). After the lead-in phase, subjects were monitored during a 4-week dose titration phase, and an 8-week maintenance phase. Psychophysiologic testing occurred after 4 weeks on HCTZ (Time 1), and again after 12 weeks on HCTZ and either AT or EN (Time 2). Testing consisted of a 5-minute resting period followed by 5 minutes of mental arithmetic, performed while cardiovascular responses were monitored. Cardiovascular reactivity scores were calculated at both times of measurement. Time 2 reactivity scores were analyzed by analysis of covariance, covarying reactivity scores at Time 1. Results. Heart rate reactivity at Time 2 was significantly less for the AT group than for the EN group. However, blood pressure reactivity was significantly less in the EN group than the AT group. Conclusions. These results are consistent with previous studies of beta-blockers, but suggest the potential efficacy of EN in attenuating blood pressure reactivity to mental stress.