The Obstinate Refractory and Resistance Hypertension

Raj Kamal Choudhry,Amrendra Kumar Singh

doi:10.11648/j.ajim.20200805.13

Abstract

Resistant hypertension (RHTN) is relatively common with an estimated prevalence of 10-20% of treated hypertensive patients. It is defined as blood pressure (BP) >140/90 mmHg treated with ≥3 antihypertensive medications, including a diuretic, if tolerated. Refractory hypertension is a novel phenotype of severe antihypertensive treatment failure. The proposed definition for refractory hypertension, i.e. BP >140/90 mmHg with use of ≥5 different antihypertensive medications, including a diuretic <i>and</i> a mineralocorticoid receptor antagonist (MRA) has been applied inconsistently. In comparison to RHTN, refractory hypertension seems to be less prevalent than RHTN. This review focuses on current knowledge about this novel phenotype compared with RHTN including definition, prevalence, mechanisms, characteristics and comorbidities, including cardiovascular risk. In patients with RHTN excess fluid retention is thought to be a common mechanism for the development of RHTN. Recently, evidence has emerged suggesting that refractory hypertension may be more of neurogenic etiology due to increased sympathetic activity as opposed to excess fluid retention. Treatment recommendations for RHTN are generally based on use and intensification of diuretic therapy, especially with the combination of a long-acting thiazide-like diuretic and an MRA. Based on findings from available studies, such an approach does not seem to be a successful strategy to control BP in patients with refractory hypertension and effective sympathetic inhibition in such patients, either with medications and/or device based approaches may be needed.

Highlights

With the introduction of antihypertensive pharmacological treatment in the last century, evidence emerged that the blood pressure (BP) response to treatment varies between individuals and that some patients require more medications to control their BP than others
Resistant hypertension As defined in a scientific statement by the American Heart Association Professional Education Committee of the Council for High Blood Pressure Research on Resistant Hypertension, resistant hypertension (RHTN) is defined as uncontrolled BP (>140/90 mmHg) despite use of ≥ 3 antihypertensive medications, including a diuretic, if tolerated [5, 6]
The prevalence of refractory hypertension as 2.7% of patients referred to a hypertension specialty clinic for uncontrolled RHTN, based on having never achieved blood pressure control with use of ≥ 5 or more medications, including chlorthalidone 25 mg daily and spironolactone 25 mg daily after 3 follow up visits confirmed by 24-hr ambulatory BP monitoring [9,10,11]

Summary

Introduction

With the introduction of antihypertensive pharmacological treatment in the last century, evidence emerged that the blood pressure (BP) response to treatment varies between individuals and that some patients require more medications to control their BP than others. The terms “refractory” and “resistant” hypertension were first used more than six decades ago to characterize such patients [1]. Both terms were interchangeably applied to identify patients with difficult-to-treat hypertension [2, 3]. The term refractory hypertension has been proposed to refer to patients failing maximal antihypertensive treatment defined as lack of BP control despite treatment with at least 5 different antihypertensive agents, including a diuretic and a mineralocorticoid receptor antagonist (MRA) [4]

Findings

Discussion

Conclusion