Effect of mineralocorticoid antagonists on blood pressure lowering: overview and meta-analysis of randomized controlled trials in hypertension

Spironolactone improves left atrial function and atrioventricular coupling in patients with resistant hypertension

To determine the blood pressure independent effects of spironolactone on left atrial (LA) size and function in patients with resistant hypertension (RHTN). Patients with RHTN (n = 36, mean age 55 ± 7) were prospectively recruited. Spironolactone was initiated at 25 mg/day and increased to 50 mg/day after 4 weeks. Other antihypertensives were withdrawn to maintain constant blood pressure. Cardiac magnetic resonance imaging was performed at baseline and after 6 months of spironolactone treatment and changes in LA functional metrics were assessed. LA size and function parameters were improved (p < 0.05) from baseline to month-6: LA volumes indexed to body surface area (LAVI) were reduced (LAVImaximum 41.4 ± 12 vs. 33.2±9.7 mL/m2; LAVIpre-A 32.6 ± 9.8 vs. 25.6 ± 8.1 mL/m2; median LAVIminimum 18.5 [13.9-24.8] vs. 14.1 [10.9-19.2] mL/m2); left atrioventricular coupling index was reduced (28.2 ± 11.5 vs. 22.7 ± 9.2%); LA emptying fractions (LAEF) were increased (median total LAEF 52.4 [48.7-60.3] vs. 55.9 [50.3-61.1] %; active LAEF 40.2 ± 8.6 vs. 43.1 ± 7.8%). LA global longitudinal strain in the active phase was increased (16.3 ± 4.1 vs. 17.8 ± 4.2%). The effect of spironolactone was similar in patients with high (N = 18) and normal (N = 18) aldosterone status (defined by plasma renin activity and 24-h urine aldosterone). Treatment of RHTN with spironolactone is associated with improvements in LA size and function, and atrioventricular coupling, regardless of whether aldosterone levels were normal or high at baseline. This study suggests the need for larger prospective studies examining effects of mineralocorticoid receptor antagonists on atrial function and atrioventricular coupling.

Management of Resistant Hypertension

Resistant hypertension (RH) is a severe form of hypertension associated with increased cardiovascular risk. Although true RH affects less than 10% of the patients receiving antihypertensive therapy, the absolute number is high and continues to increase. The workup of these patients requires screening for secondary hypertension and pseudoresistance, including poor adherence to prescribed medicines and the white-coat phenomenon. The treatment of RH consists of lifestyle modifications and pharmacological therapies. Lifestyle modifications include dietary adjustments, weight loss, physical activity, and limiting alcohol consumption; pharmacological therapies include diuretics, mineralocorticoid receptor antagonists, beta blockers, angiotensin receptor-neprilysin inhibitors, and others. Over the last 15 years, interventional approaches have emerged as adjunct treatment options; we highlight catheter-based renal denervation. This review summarizes the rationales and latest clinical evidence and, based thereon, proposes an updated algorithm for the management of RH.

Thiazide diuretics alone or combined with potassium-sparing diuretics to treat hypertension: a systematic review and network meta-analysis of randomized controlled trials

BACKGROUND

The magnitude of blood pressure (BP)-lowering effects and decrease of the adverse effects of thiazide diuretics provided by potassium-sparing diuretics remain uncertain. The aim of this study was to compare the BP-lowering efficacy and the incidence of adverse effects of high (T+) and low-dose (T-) thiazide diuretics, alone or combined with high (PS+) or low-dose (PS-) potassium-sparing diuretics in patients with primary hypertension.

METHODS

A systematic literature search was performed in PubMed/MEDLINE, the Cochrane Central Register of Controlled Trials, Embase, Web of Science, Scopus and LILACS. Randomized double-blind placebo or active-controlled trials (RCT) with 3 weeks to 1 year of follow-up were included. Sample size, mean and standard deviation from baseline, follow-up and change from baseline values were extracted by two independent reviewers. Pairwise random effect models and Bayesian network meta-analysis models were used to compare the effects of treatments. The risk of bias in individual studies was assessed using the Rob 1.0 tool. The primary outcome was the mean difference in office SBP. Secondary outcomes were the mean difference in biochemical parameters and the incidence of nonmelanoma skin cancer.

RESULTS

Two hundred and seventy-six double-blind RCTs involving 58 807 participants (mean age: 55 years; 45% women) were included. All treatment groups were more effective than placebo in lowering BP, with mean differences (MDs) of change from baseline ranging from -7.66 mmHg [95% credible interval (95% CrI), -8.53 to -6.79] for T- to -12.77 mmHg (95% CrI, -15.22 to -10.31) for T+PS-. T+ alone or combined with potassium-sparing was more effective in reducing BP than T-. The surface under the cumulative ranking curve (SUCRA) estimated ranking showed that the best effectiveness in lowering SBP was found for T+PS- (0.69), T+PS+ (0.65) and T+ (0.54). Compared with placebo, all treatments (except T-PS-) were associated with more potassium reduction and T+ compared with all other treatments and T- when compared with T-PS-. Compared with placebo, all active treatments (except T+PS+) showed higher elevations of uric acid. The increase of plasma glucose promoted by thiazides alone was reduced by potassium-sparing agents.

CONCLUSION

Thiazides with potassium-sparing diuretics are associated with increased BP-lowering efficacy compared with thiazides alone while minimizing hypokalaemia and hyperglycaemia. These findings demonstrate that thiazide and potassium-sparing diuretic combination is preferable to thiazide alone in treating hypertension.

Thiazide diuretics alone or in combination with a potassium-sparing diuretic on blood pressure-lowering in patients with primary hypertension: protocol for a systematic review and network meta-analysis

BACKGROUND

The use of thiazide (T) diuretics for the treatment of hypertension may be associated with adverse metabolic effects, which can be minimized by combining thiazides with potassium-sparing (PS) diuretics. The additional blood pressure (BP)-lowering effect provided by the addition of a PS diuretic is unclear. Due to a large number of drugs in the T diuretics class, and the possible difference between them, there is a need to identify the best available evidence for health decision-making. This systematic review with network meta-analysis aims to compare the antihypertensive efficacy of T diuretics alone or in combination with a PS diuretic in patients with primary hypertension, as well as the safety of such drugs through the measurement of drug-related adverse events.

METHODS

A comprehensive electronic search will be conducted in six electronic bibliographic databases (PubMed/MEDLINE, Cochrane Library, Embase, Web of Science, Scopus, Lilacs), a registration database ( ClinicalTrials.gov ), and Educational Resources Information Center (ERIC [ProQuest]), published from inception to the date of the search. The search will be updated towards the end of the review. A hand search of the reference sections of the included studies and cited studies will also be performed. In case of missing data, authors will be contacted by e-mail or academic social networking sites whenever possible. To be included in the review, studies must be double-blind randomized controlled trials evaluating T diuretics alone or in combination with PS diuretics in patients with primary hypertension. The primary outcome measure will be office BP. Ambulatory BP monitoring (ABPM), non-melanoma skin cancer, major adverse cardiovascular events, laboratory parameters, and the number of withdrawals will be included as secondary outcomes. The results will be quantitatively summarized using differences between the mean change from baseline or differences between means for quantitative outcomes and relative risk for dichotomous outcomes. Results will be presented as mean or relative risk with credible intervals through a league table. The treatments will also be ranked using the surface under the cumulative ranking curve method. The risk of bias will be assessed through the RoB 1.0 tool.

DISCUSSION

To the best of our knowledge, this review will be the first to synthesize currently available evidence on the antihypertensive efficacy of different T diuretics alone or in combination with PS diuretics in adults with hypertension. The goals of hypertension treatment are to control high BP and to reduce associated cardiovascular morbidity and mortality, using the most appropriate therapy. Thiazides are widely used for pharmacological treatment due to their demonstrated effectiveness in reducing BP, favorable safety profile, and low cost. The results of this study will provide evidence regarding the best therapeutic strategies with T and PS diuretics, evidencing interventions with better antihypertensive efficacy and safety profile.

TRIAL REGISTRATION

This systematic review and network meta-analysis was prospectively registered at the PROSPERO database ( CRD42018118492 ).

Resolution of drug-resistant hypertension by adrenal vein sampling-guided adrenalectomy: a proof-of-concept study

Drug-resistant hypertension (RH) is a very high-risk condition involving many hypertensive patients, in whom primary aldosteronism (PA) is commonly overlooked. Hence, we aimed at determining if (1) adrenal vein sampling (AVS) can identify PA in RH patients, who are challenging because of receiving multiple interfering drugs; (2) AVS-guided adrenalectomy can resolve high blood pressure (BP) resistance to treatment in these patients.

Based on a pilot study we selected from 1016 consecutive patients referred to our Centre for ‘difficult-to-treat’ hypertension those with RH, for an observational prospective cohort study. We excluded those non-adherent to treatment (by therapeutic drug monitoring) and those with pseudo-RH (by 24-h BP monitoring), which left 110 patients who met the European Society of Cardiology/European Society of Hypertension (ESC/ESH) 2013 definition for RH. Of these patients, 77 were submitted to AVS, who showed unilateral PA in 27 (mean age 55 years; male/female 19/8). Therefore, these patients underwent AVS-guided laparoscopic unilateral adrenalectomy, which resolved RH in all: 20% were clinically cured in that they no longer needed any antihypertensive treatment; 96% were biochemically cured. Systolic and diastolic BP fell from 165/100 ± 26/14 mmHg at baseline, to 132/84 ± 14/9 mmHg at 6 months after surgery (P&lt;10−4 for both) notwithstanding the fall of number and defined daily dose (DDD) of antihypertensive drugs required to achieve BP control (P&lt;10−4 for both). A prominent regression of cardiac and renal damage was also observed.

Thus, the present study shows the feasibility of identifying PA by AVS in RH patients, and of resolving high BP resistance to treatment in these patients by AVS-guided adrenalectomy.

Primary Aldosteronism: JACC State-of-the-Art Review

Primary aldosteronism (PA) is a common, but frequently overlooked, cause of arterial hypertension and excess cardiovascular events, particularly atrial fibrillation. As timely diagnosis and treatment can provide a cure of hyperaldosteronism and hypertension, even when the latter is resistant to drug treatment, strategies to screen patients for PA early with a simplified diagnostic algorithm are justified. They can be particularly beneficial in some subgroups of hypertensive patients, as those who are at highest cardiovascular risk. However, identification of the surgically curable cases of PA and achievement of optimal results require subtyping with adrenal vein sampling, which, as it is technically challenging and currently performed only in tertiary referral centers, represents the bottleneck in the work-up of PA. Measures aimed at improving the clinical use of adrenal vein sampling and at developing alternative techniques for subtyping, alongside recommendations for drug treatment, including new development in the field, and for follow-up are discussed.

The 2020 Italian Society of Arterial Hypertension (SIIA) practical guidelines for the management of primary aldosteronism

Background and aim

Considering the amount of novel knowledge generated in the last five years, a team of experienced hypertensionlogists was assembled to furnish updated clinical practice guidelines for the management of primary aldosteronism.

Methods

To identify the most relevant studies, the authors utilized a systematic literature review in international databases by applying the PICO strategy, and then they were required to make use of only those meeting predefined quality criteria. For studies of diagnostic tests, only those that fulfilled the Standards for Reporting of Diagnostic Accuracy recommendations were considered.

Results

Each section was jointly prepared by at least two co-authors, who provided Class of Recommendation and Level of Evidence following the American Heart Association methodology. The guidelines were sponsored by the Italian Society of Arterial Hypertension and underwent two rounds of revision, eventually reexamined by an External Committee. They were presented and thoroughly discussed in two face-to-face meetings with all co-authors and then presented on occasion of the 36th Italian Society of Arterial Hypertension meeting in order to gather further feedbacks by all members. The text amended according to these feedbacks was subjected to a further peer review.

Conclusions

After this process, substantial updated information was generated, which could simplify the diagnosis of primary aldosteronism and assist practicing physicians in optimizing treatment and follow-up of patients with one of the most common curable causes of arterial hypertension.

Mineralocorticoid Receptor Antagonists in Essential and Resistant Hypertension

Background:

Mineralocorticoid receptor antagonists are a second-line class of antihypertensive drugs, which have been accounted for as the optimal add-on therapy in the triple algorithm for the management of resistant hypertension.

Objectives:

To assess the effects of mineralocorticoid receptor antagonists in the treatment of patients with essential hypertension and resistant hypertension.

Method:

We conducted a meticulous review of the literature and comprehensive identification of the clinical trials assessing the efficacy of mineralocorticoid receptor antagonists in individuals with primary and resistant hypertension.

Results:

MRAs have been thoroughly tested in several clinical studies in relevance to blood pressure lowering effects, over the last six decades. Accumulating data observed that MRAs resulted in a significant reduction in blood pressure level in patients with resistant hypertension. In addition, spironolactone was found to beneficially affect the management of resistant hypertension.

Conclusion:

Mineralocorticoid receptor antagonists exert a significant antihypertensive effect. Future welldesigned randomized controlled studies are greatly needed to address crucial clinical aspects in the field.

Is the plasma aldosterone-to-renin ratio associated with blood pressure response to treatment in general practice?

BACKGROUND

Individualized antihypertensive treatment based on specific biomarkers such as renin may lead to more effective blood pressure control in patients with newly diagnosed essential hypertension. Recent studies suggested that the plasma aldosterone-to-renin ratio (ARR) may also be a candidate predictor for this purpose.

OBJECTIVE

To assess whether the ARR is associated with the blood pressure response to antihypertensive treatment in patients with newly diagnosed hypertension.

METHODS

In this prospective cohort study in primary care, we determined the ARR in patients with newly diagnosed hypertension prior to starting treatment. Treatment was categorized in five groups: no medication, use of angiotensin-converting-enzyme inhibitor or angiotensin receptor blocker, use of calcium channel blocker, use of diuretic, or use of beta blocker. We examined the relation between the ARR and blood pressure response within 1 year of treatment, taking into account the type of antihypertensive treatment and adjusting for gender, age, baseline blood pressure, and comorbidity.

RESULTS

Out of 304 patients, we used 947 measurements (727 no medication, 220 medication) for analysis. There was no association between the ARR and the response in blood pressure, and this applied to each treatment group. Target blood pressure, defined as systolic blood pressure <140 mmHg, was reached in 31% of patients. There was no association between the ARR and reaching target blood pressure (OR 1.002, 95% CI 0.983-1.022).

CONCLUSION

The ARR is not associated with the response in blood pressure within 1 year of antihypertensive treatment in primary care.

Is there a blood pressure lowering effect of MRAs in heart failure? An overview and meta-analysis

Although mineralocorticoid antagonists (MRAs) have been proposed as effective fourth-line blood pressure (BP) lowering agents in resistant hypertension, this effect in heart failure is undetermined. In this synthesis of heart failure randomized controlled trials (RCTs), we evaluated the extent of BP lowering following MRA treatment against placebo. We searched Medline and the Cochrane Collaboration Library databases from 1991 to September 2016 for RCTs, in which MRAs were compared with placebo. The quality of RCTs was assessed with Cochrane risk of bias tool. Outcomes were the extent of systolic and diastolic BP lowering. We included seven studies (13,354 patients, 65.8% males, mean age of 66.3 years, mean follow-up period of 9.4 months, mean baseline BP of 123.5/75.0 mmHg) of MRAs compared with placebo. MRAs were not significantly associated with systolic - 1.8 (95% CI: - 8.0, 4.4) mmHg or diastolic - 0.3 (95% CI: - 3.4, 2.7) mmHg, BP reduction. Although systolic BP was not lowered by spironolactone, diastolic BP was lowered by - 3.0 (95% CI: - 3.4, - 2.6) mmHg. Eplerenone treatment did not significantly lowered systolic [- 0.04 (95% CI: - 4.4, 4.3) mmHg], but it was associated with minimal diastolic BP increase [1.0 (95% CI: 0.5, 1.53) mmHg]. MRAs were not associated with systolic and diastolic BP reduction in heart failure patients. This finding suggests that MRAs should be used according to their indications in heart failure independently of initial BP levels.