Resistant hypertension: a review

Abstract

Resistant hypertension is currently defined as uncontrolled blood pressure despite the use of optimal doses of three antihypertensive medications, of which one is a diuretic. Several factors have been identified as contributors to resistant hypertension such as poor patient adherence, physician inertia, inadequate doses or inappropriate combinations of antihypertensive drugs, excess alcohol intake, certain drugs and volume overload. Uncontrolled blood pressure is a considerable cardiovascular and neurological risk factor that can lead to possible end-organ consequences of untreated hypertension, including heart failure, stroke, ischemic heart disease and renal failure. A comprehensive history and physical examination are essential for pointing towards to an underlying diagnosis. A PubMed search was conducted for review articles and papers from 1955 to 2019 containing the keywords ‘resistant hypertension’, ‘secondary hypertension’, ‘refractory hypertension’, ‘heart failure’ and ‘stroke’, and the literature was compiled. Non-pharmacological measures chiefly include lifestyle modifications such as smoking cessation, reduction in alcohol intake, dietary sodium restriction, healthy eating plans, increased physical activity and weight loss. Among recommended drugs, spironolactone and beta blockers are the preferred fourth- and fifth-line drugs respectively, in patients unresponsive to ACE Inhibitors, calcium channel blockers as well as diuretics. Although most patients are well controlled on extended drug regimes, some develop refractory hypertension which does not even respond to the five-drug regimen. Interventional therapies such as renal denervation and carotid sinus stimulation have been developed for patients with refractory hypertension, but still require further research and follow up to ascertain their full potency and efficacy.