A pressor effect of noncardioselective beta-blockers in mildly hypertensive patients during acute hospitalization

Abstract

Pressor effects of noncardioselective beta-blockers have been demonstrated in situations of increased sympathetic activity; however, data are limited and the clinical significance of this finding is in doubt. The present study was performed to supply data about the effect of noncardioselective beta-blockers on the stress of acute hospitalization. Of 2,989 patients acutely admitted to a 50-bed unit of general internal medicine in a 647-bed teaching hospital, 234 had used beta-blockers without intrinsic sympathicomimetic activity (ISA) for at least six weeks because of mild hypertension; 199 were evaluable, 56 using nonselective, 143 using selective beta-blockers. The authors found a marked pressor effect of noncardioselective beta-blockers as compared with selective (mean arterial pressure 125 versus 102 mm Hg, p less than 0.001). In the patients who could continue their outpatient medication this effect could be attributed to an overall increase of total peripheral resistance and disappeared within five days of admission. In the patients admitted because of unstable angina pectoris (nonselective n = 15, selective n = 48) myocardial oxygen demand as estimated by the double product (systolic blood pressure heart rate) was significantly higher in the nonselective group (12.926 versus 9.581 mmHg.beats/min, p less than 0.01). The present study supports the need for more controlled data to determine the ultimate place of noncardioselective beta-blockers in situations of increased sympathetic activity.