SOURCE: Aparicio LS, et al. Comparison of atenolol versus bisoprolol with noninvasive hemodynamic and pulse wave assessment. J Am Society Hypertens 2015;9:390-396.
Aside from beta-receptor selectivity (beta-1 receptors for cardiac function, beta-2 for pulmonary function), clinicians do not often distinguish major differences within the class of beta-blockers. Of course, alpha-beta-blockers (e.g., carvedilol, labetalol) are not really beta-blockers in the traditional sense, because they also provide alpha-receptor blockade. There’s also nebivolol, the nitric-oxide enhancing beta-blocker associated with — in contrast to most other beta-blockers — peripheral vasodilation (traditional beta-blockers being associated with peripheral vasoconstriction that may result in complaints, for instance, of cold extremities).
In 2006, it was brought to the attention of clinicians that while various drugs may lower BP equivalently, they may not always reduce cardiovascular (CV) endpoints to the same degree. In the ASCOT trial, which compared amlodipine to atenolol, CV outcomes were more favorable with amlodipine, despite similar BP results. The CAFÉ trial (Conduit Artery Function Evaluation) determined that even though arm BP (sometimes called peripheral BP) was similar with either drug (amlodipine or atenolol), central BP (measured at the level of the aorta) decreased substantially better with amlodipine. Such differences might explain the advantageous outcomes results in favor of amlodipine.
Aparicio et al compared central BP effects of bisoprolol and atenolol, and found them to be comparable. Whether clinicians should choose pharmacotherapy based on central BP effects has not been confirmed, although hypertension guidelines throughout the world have increasingly recognized the inadequacy of traditional beta-blockers in comparison to most other classes of agents and relegated them to a lower position on the therapeutic ladder.