Angiotensin Receptor Blockers Versus Angiotensin Converting Enzyme Inhibitors for the Treatment of Arterial Hypertension and the Role of Olmesartan

Blood pressure lowering by all classes of antihypertensive drugs is accompanied by significant reductions of stroke and major cardiovascular (CV) events. Drugs acting on the renin–angiotensin–aldosterone system, such as angiotensin converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs), showed similar benefit on major CV events to other antihypertensive medications. In real-world practice, ARBs reduced by 10% the incidence of CV mortality, non-fatal myocardial infarction, non-fatal stroke and provided superior protection against CV events than ACEIs in high-risk patients. Despite similar antihypertensive properties and a favourable safety profile for both ACEIs and ARBs, evidence indicates that patients treated with ARBs have lower rates of withdrawal for adverse events and greater persistence to therapy than those treated with ACEIs. Among ARBs, olmesartan is one of the latest generation compounds introduced in clinical practice for treating hypertension: head-to-head comparative trials suggest that the efficacy of olmesartan is superior to that of commonly prescribed ACEIs (ramipril and perindopril). The drug, administered as a monotherapy or in combination with a dihydropyridine calcium channel blocker or a thiazide diuretic, has proved to be effective in maintaining blood pressure stability over 24 h, with a favourable safety profile and low discontinuation rates. These properties are pivotal for considering olmesartan as a useful antihypertensive agent especially for high-risk patients (e.g. elderly, diabetics, patients with metabolic syndrome).