Key Points
- To determine the hemodynamic responses provoked by sustained mental arithmetic in normotensive and hypertensive individuals and evaluate how selective and non-selective beta-adrenoceptor blockade modifies these effects.
- Measured blood pressure and heart rate responses during a 5-minute period of sustained mental arithmetic in healthy subjects and hypertensive patients.
- Conducted a double-blind crossover comparison evaluating the beta1-selective blocker metoprolol against the non-selective blocker propranolol during arithmetic stress.
- Mental arithmetic induced significant increases in heart rate along with systolic and diastolic blood pressure across normotensive and hypertensive groups.
- Blood pressure elevations were neither attenuated nor enhanced following beta-adrenoceptor blockade.
- Heart rate increases were attenuated by beta-blockers in subjects unfamiliar with the test, whereas hemodynamic reactivity did not differ between selective beta1-blockade and combined beta1- and beta2-receptor blockade.
Structured PICO
Does beta-adrenergic receptor blockade modify the blood pressure and heart rate response to mental arithmetic in normotensive and hypertensive subjects?
PPopulationHealthy subjects (normotensive) and hypertensive patients
IIntervention5-min period of sustained mental arithmetic with prior administration of beta-blockers (metoprolol or propranolol)
CComparatorBaseline (no drug) and active comparator (metoprolol vs propranolol in a double-blind crossover comparison)
OOutcomeChanges in blood pressure (systolic and diastolic) and heart ratesurrogate
Beta-blockade does not attenuate the blood pressure increase caused by minor mental stress, and non-selective blockade does not exaggerate these hemodynamic effects compared to beta1-selective blockade.