Background: It is unclear whether the assumed inferiority of atenolol to reduce central (aortic) blood pressure (BP) extends to other β-blockers with vasodilating properties and, within that scope, how these drugs differ from the angiotensin receptor blockers (ARBs).
Methods: In a retrospective study, we compared three groups of hypertensive patients (aged 35-65 years) chronically treated with either ARBs (n=83, group 1), carvedilol/nebivolol (n=75, 25+25 mg/day/5 mg/day, group 2) or atenolol (n=84, 50-100 mg/day, group 3), matched for age (mean 52 years), sex (61% female), brachial BP and concomitant use of diuretics (75-81%)and dihydropyridine calcium antagonists (27-33%). We measured aortic stiffness by pulse wave velocity (Complior), and central BP, central-peripheral pulse pressure amplification, wave reflection [augmentation index (AIx) corrected for heart rate] and augmentation pressure (Sphygmocor).
Results: For similar age, sex distribution, brachial BP levels (145/85±11/10 mmHg) and pulse wave velocity (10±2 m/s), the atenolol group showed significantly (P<0.03 analysis of variance) higher central systolic BP (139±9 mmHg) versus group 2 (135±10 mmHg) and group 1 (132±11 mmHg), higher AIx (34±12%) versus group 2 (27±7%) and group 1 (23.0±9%), lower pulse pressure amplification (1.16±0.09) versus group 2 (1.22±0.10) and group 1 (1.31±0.11) and lower heart rate beats/min (61±9) versus group 2 (69±11) and group 1 (82±11). The differences on these values, between group 2 and group 1, were also significant (P<0.04). After adjustment for the heart rate, AIx became similar in groups 2 and 1, but still lower (P<0.04) than the atenolol group.
Conclusion: These findings suggest that, for similar brachial BP and aortic stiffness, treatment with either vasodilating β-blockers or angiotensin receptor blockers associates with lower central systolic BP and wave reflections than treatment with atenolol. These findings may suggest that the vasodilating β-blockers may exert more favourable central haemodynamic effects, compared with atenolol, which are more alike, although not completely equal, to those of the ARBs.