Antihypertensive and cardioprotective effects of three generations of beta-adrenergic blockers: an historical perspective

There are currently three generations of beta-adrenergic blockers for the treatment of hypertension and cardiovascular diseases. The 1^st generation caused vasoconstriction and bronchoconstriction due to β₁ + β₂ receptor blockade and unopposed α₁ receptors. The 2^nd generation of beta-blockers has lesser adverse effects than the 1^st generation with the 3^rd generation beta-blockers having much lesser effects than the other two generations. Current US and International guidelines do not recommend beta-blockers as first-line therapy of hypertension, but only in the presence of coronary artery disease or heart failure due to their lesser antihypertensive effect. These recommendations are disputed by several older and recent studies which have shown that the beta-blockers are effective and safe for the treatment of hypertension and could be used as first-line therapy. To clarify this issue a Medline search of the English language literature was conducted between 2012 and 2021 and 30 pertinent papers were selected. The data from these studies show that the beta-blockers have inferior antihypertensive and stroke protective effect compared with the other classes of antihypertensive drugs and should be used as first line therapy only in patients with hypertension associated with coronary artery disease or heart failure. The information from these papers and collateral literature will be discussed in this perspective.