Impact of Medication Adherence on the Effect of Renal Denervation

Assessing the efficacy of renal denervation in patients with resistant arterial hypertension : Systematic review and meta-analysis

BACKGROUND

Renal denervation (RDN) is an innovative procedure designed to regulate the renal sympathetic nervous system for the control of arterial hypertension (HTN). RDN has emerged as an alternative for patients with resistant HTN. However, the clinical efficacy of RDN remains incompletely elucidated.

METHODS

PubMed, Embase, and Cochrane databases were searched for randomized controlled trials (RCTs) comparing the use of RDN with sham procedure or pharmacological treatment in patients with resistant HTN. Statistical analyses were performed using R Studio 4.3.2 (R Foundation for Statistical Computing, Vienna, Austria). Heterogeneity was examined with the Cochran Q test I2 statistics. Mean difference (MD) with 95% confidence interval (CI) were pooled across trials. P values of <0.05 were considered statistically significant. The primary outcomes of interest were changes from baseline in systolic blood pressure (SBP), diastolic blood pressure (DBP), and serum creatinine.

RESULTS

Twenty-one RCTs comprising 3345 patients were included in this meta-analysis, whereby 2004 (59.91%) received renal denervation and 1341 (40.09%) received pharmacological treatment or sham procedure. Follow-up ranged from 2 to 48 months. Compared to control group, RDN significantly reduced SBP (MD -3.53 mm Hg; 95% CI -5.94 to -1.12; p = 0.004; I2 = 74%) and DBP (MD -1.48 mm Hg; 95% CI -2.56 to -0.40; p = 0.007; I2 = 51%). Regarding serum creatinine (MD -2.51; 95% CI -7.90 to 2.87; p = 0.36; I2 = 40%), there was no significant difference between RDN and control groups.

CONCLUSION

In this meta-analysis of RCTs of patients with resistant HTN, RDN was associated with a reduction in SBP and DBP compared to sham procedure or pharmacological treatment.

Randomized Trials of Renal Denervation for Uncontrolled Hypertension: An Updated Meta-Analysis

BACKGROUND

Despite optimal medical therapy, a significant proportion of patients' blood pressure remains uncontrolled. Catheter-based renal denervation (RDN) has been proposed as a potential intervention for uncontrolled hypertension. We conducted an updated meta-analysis to assess the efficacy and safety of RDN in patients with uncontrolled hypertension, with emphasis on the differential effect of RDN in patients on and off antihypertensive medications.

METHODS AND RESULTS

Online databases were searched to identify randomized clinical trials comparing efficacy and safety of RDN versus control in patients with uncontrolled hypertension. Subgroup analyses were conducted for sham-controlled trials and studies that used RDN devices that have gained or are currently seeking US Food and Drug Administration approval. Fifteen trials with 2581 patients (RDN, 1723; sham, 858) were included. In patients off antihypertensive medications undergoing RDN, a significant reduction in 24-hour ambulatory (-3.70 [95% CI, -5.41 to -2.00] mm Hg), office (-4.76 [95% CI, -7.57 to -1.94] mm Hg), and home (-3.28 [95% CI, -5.96 to -0.61] mm Hg) systolic blood pressures was noted. In patients on antihypertensive medications, a significant reduction was observed in 24-hour ambulatory (-2.23 [95% CI, -3.56 to -0.90] mm Hg), office (-6.39 [95% CI, -11.49 to -1.30]), home (-6.08 [95% CI, -11.54 to -0.61] mm Hg), daytime (-2.62 [95% CI, -4.14 to -1.11]), and nighttime (-2.70 [95% CI, -5.13 to -0.27]) systolic blood pressures, as well as 24-hour ambulatory (-1.16 [95% CI, -1.96 to -0.35]), office (-3.17 [95% CI, -5.54 to -0.80]), and daytime (-1.47 [95% CI, -2.50 to -0.27]) diastolic blood pressures.

CONCLUSIONS

RDN significantly lowers blood pressure in patients with uncontrolled hypertension, in patients off and on antihypertensive medications, with a favorable safety profile. The efficacy of RDN was consistent in sham-controlled trials and contemporary trials using US Food and Drug Administration-approved devices.

Value of interventional radiology and their contributions to modern medical systems

Interventional radiology (IR) is a unique specialty that incorporates a diverse set of skills ranging from imaging, procedures, consultation, and patient management. Understanding how IR generates value to the healthcare system is important to review from various perspectives. IR specialists need to understand how to meet demands from various stakeholders to expand their practice improving patient care. Thus, this review discusses the domains of value contributed to medical systems and outlines the parameters of success. IR benefits five distinct parties: patients, practitioners, payers, employers, and innovators. Value to patients and providers is delivered through a wide set of diagnostic and therapeutic interventions. Payers and hospital systems financially benefit from the reduced cost in medical management secondary to fast patient recovery, outpatient procedures, fewer complications, and the prestige of offering diverse expertise for complex patients. Lastly, IR is a field of rapid innovation implementing new procedural technology and techniques. Overall, IR must actively advocate for further growth and influence in the medical field as their value continues to expand in multiple domains. Despite being a nascent specialty, IR has become indispensable to modern medical practice.

Renal denervation for uncontrolled hypertension: a systematic review and meta-analysis examining multiple subgroups

This systematic review and meta-analysis was conducted to assess the randomized controlled trial (RCT) evidence available for renal denervation (RDN) in uncontrolled arterial hypertension. Twenty-five RCTs met the eligibility criteria for the systematic review, and 16 RCTs were included in the meta-analysis. The results of the random effects meta-analysis estimated a mean difference of -8.5 mmHg [95% confidence interval (CI) -13.5 to -3.6] for office SBP, -3.6 mmHg (95% CI -5.2 to -2.0) for 24 h SBP and -3.9 mmHg (95% CI -5.6 to -2.2) for ambulatory daytime SBP in favour of RDN compared with control (medication and/or sham-only) at primary follow-up. Similarly favourable results were observed across a range of prespecified subgroup analyses, including treatment-resistant hypertension. This meta-analysis suggests that the use of RDN in uncontrolled hypertension leads to consistent reductions in blood pressure. Reductions appear to be statistically consistent in the presence or absence of medications and in populations resistant to the use of three medications.

Physician and patient adherence in hypertension trials: a point of view on an important issue to resolve

INTRODUCTION

Randomized controlled trials (RCTs) are important sources of evidence that strongly influence guidelines for patient management, including for elevated blood pressure in adults.

AREAS COVERED

Critical questions regarding the interpretation of hypertension trial results have recently increased, especially for concerns over methodology. In particular, investigator adherence to the protocol and patient adherence to investigational drugs are often far from optimal. These issues may be ignored or underreported because physicians' behavior during trials is often not monitored and patients' medication adherence is neither measured adequately nor reported or analyzed in the final report or in the publication. This situation may lead to misinterpretations of study results and misevaluations of the safety and efficacy profile of new drugs. In this short review, the problem of measuring, reporting, and analyzing drug adherence in RCTs is discussed and illustrated with several examples in the field of hypertension.

EXPERT OPINION

The main conclusion is that drug adherence should always be measured in clinical trials, possibly with more than one method. In addition, prespecified analyses of adherence data should be included in the statistical plan of all trials to improve their overall quality.

Impact of poor medication adherence on clinical outcomes and health resource utilization in patients with hypertension and/or dyslipidemia: systematic review

INTRODUCTION

We aimed to summarize evidence on the effect of poor medication adherence on clinical outcomes and health resource utilization (HRU) among patients with hypertension and/or dyslipidemia.

AREAS COVERED

A systematic review of studies reporting clinical outcomes and HRU for patients by status of adherence to antihypertensives and/or lipid-lowering medications was searched using Embase, MEDLINE, and MEDLINE In-Process and supplemented by manual searches of conference abstracts. In total, 45 studies were included, with most being retrospective observational studies (n = 36). Patients with poor adherence to antihypertensives and lipid-lowering medications compared with those with good adherence showed less reduction of blood pressure (BP) and low-density lipoprotein cholesterol (LDL-c) after 6-12 months follow-up (∆ systolic BP: 1.2 vs. -4.5 mmHg; ∆LDL-c: -14.0 to -18.9 vs. -34.1 to -42.0 mg/dL). Poor adherence was also significantly associated with a higher risk of cardiovascular events (HR: 1.1-1.9) and mortality (HR: 1.4-1.8) in patients with hypertension and dyslipidemia and increased HRU (i.e. outpatient visits, risk of cardiovascular-related and all-cause hospitalization, annual inpatient days, total health-care costs).

EXPERT OPINION

Poor adherence is associated with poor clinical outcomes and increased HRU, highlighting the need to enhance medication adherence in patients with hypertension and/or dyslipidemia.

Controversies in Hypertension IV: Renal Denervation

Renal denervation is not a cure for hypertension. Although more recent sham-controlled trials were positive, a significant minority of patients in each trial were unresponsive. The optimal patient or patients need to be defined. Combined systolic/diastolic hypertension appears more responsive than isolated systolic hypertension. It remains uncertain whether patients with comorbidities associated with higher adrenergic tone should be targeted, including obesity, diabetes, sleep apnea, and chronic kidney disease. No biomarker can adequately predict response. A key to a successful response is the adequacy of denervation, which currently cannot be assessed in real time. It is uncertain what is the optimal denervation methodology: radiofrequency, ultrasound, or ethanol injection. Radiofrequency requires targeting the distal main renal artery plus major branches and accessory arteries. Although denervation appears to be safe, conclusive data on quality of life, improved target organ damage, and reduced cardiovascular events/mortality are required before denervation can be generally recommended.

Stepwise treatment of uncontrolled HyperTensioN (Stepwise-HTN): Study design of a cluster randomised controlled trial in primary care

BACKGROUND

Uncontrolled hypertension is a major health problem, and a key risk factor for cardiovascular disease. Most patients are detected and managed in primary care, but approximately 50% remains uncontrolled. Our aim is to assess whether a guided stepwise work-up management strategy for patients with uncontrolled hypertension in primary care would result in better blood pressure control in these patients compared to usual care.

METHODS

A cluster randomised controlled trial aiming at randomizing 40 general practices to either "a protocolised stepwise work-up" or to "usual care". Uncontrolled hypertension is defined as an office blood pressure (BP) >140/90 mmHg while being prescribed three or more antihypertensive drugs simultaneously from different therapeutic classes for three or more months in an adequate dose. In the intervention arm, patients with uncontrolled hypertension will receive the stepwise approach, consisting of (i) excluding a white coat effect, (ii) re-evaluation of lifestyle, (iii) re-evaluation of drug adherence, (iv) optimalisation of antihypertensive treatment and (v) referral if the office BP is still >140/90 mmHg. The control group receives usual care in a regular program for cardiovascular risk management. The primary outcome is the absolute difference in the mean 24-h systolic BP between intervention and control arm after 8 months. Secondary outcomes include differences in the percentage of patients achieving a controlled BP, and time to reach a controlled BP.

CONCLUSION

If stepwise treatment of uncontrolled hypertension is proven effective, the strategy could be implemented by blending the approach to the cardiovascular risk management already applied in general practice. Trial registration NTR7304, https://www.trialregister.nl/trial/7099.

The position of renal denervation in treatment of hypertension: an expert consensus statement

Hypertension is an important risk factor for cardiovascular disease. In the Netherlands, there are approximately 2.8 million people with hypertension. Despite treatment recommendations including lifestyle changes and antihypertensive drugs, most patients do not meet guideline-recommended blood pressure (BP) targets. In order to improve BP control and lower the risk of subsequent cardiovascular events, renal sympathetic denervation (RDN) has been introduced and studied as a non-pharmacological approach. While early data on the efficacy of RDN showed conflicting results, improvements in treatment protocols and study design resulted in robust new evidence supporting the potential of the technology to improve patient care in hypertensive subjects. Recently, 5 randomised sham-controlled trials demonstrated the safety and efficacy of the technology. Modelling studies have further shown that RDN is cost-effective in the Dutch healthcare setting. Given the undisputable disease burden along with the shortcomings of current therapeutic options, we postulate a new, clearly framed indication for RDN as an adjunct in the treatment of hypertension. The present consensus statement summarises current guideline-recommended BP targets, proposed workup and treatment for hypertension, and position of RDN for those patients with primary hypertension who do not meet guideline-recommended BP targets (see central illustration).

Renal denervation in the antihypertensive arsenal - knowns and known unknowns

Even though it has been more than a decade since renal denervation (RDN) was first used to treat hypertension and an intense effort on researching this therapy has been made, it is still not clear how RDN fits into the antihypertensive arsenal. There is no question that RDN lowers blood pressure (BP), it does so to an extent at best corresponding to one antihypertensive drug. The procedure has an excellent safety record. However, it remains clinically impossible to predict whose BP responds to RDN and whose does not. Long-term efficacy data on BP reduction are still unconvincing despite the recent results in the SPYRAL HTN-ON MED trial; experimental studies indicate that reinnervation is occurring after RDN. Although BP is an acceptable surrogate endpoint, there is complete lack of outcome data with RDN. Clear indications for RDN are lacking although patients with resistant hypertension, those with documented increase in activity of the sympathetic system and perhaps those who desire to take fewest medication may be considered.

Nonadherence by Serum Drug Analyses in Resistant Hypertension: 7-Year Follow-Up of Patients Considered Adherent by Directly Observed Therapy

Background Measurement of serum concentrations of drugs is a novelty found useful in detecting poor drug adherence in patients taking ≥2 antihypertensive agents. Regarding patients with treatment-resistant hypertension, we previously based our assessment on directly observed therapy. The present study aimed to investigate whether serum drug measurements in patients with resistant hypertension offer additional information regarding drug adherence, beyond that of initial assessment with directly observed therapy. Methods and Results Nineteen patients assumed to have true treatment-resistant hypertension and adherence to antihypertensive drugs based on directly observed therapy were investigated repeatedly through 7 years. Serum concentrations of antihypertensive drugs were measured by ultra-high-performance liquid chromatography-tandem mass spectrometry from blood samples taken at baseline, 6-month, 3-year, and 7-year visits. Cytochrome P450 polymorphisms, self-reported adherence and beliefs about medicine were performed as supplement investigations. Seven patients (37%) were redefined as nonadherent based on their serum concentrations during follow-up. All patients reported high adherence to medications. Nonadherent patients expressed lower necessity and higher concerns regarding intake of antihypertensive medication (P=0.003). Cytochrome P450 polymorphisms affecting metabolism of antihypertensive drugs were found in 16 patients (84%), 21% were poor metabolizers, and none were ultra-rapid metabolizers. Six of 7 patients redefined as nonadherent had cytochrome P450 polymorphisms, however, not explaining the low serum drug concentrations measured in these patients. Conclusions Our data suggest that repeated measurements of serum concentrations of antihypertensive drugs revealed nonadherence in one-third of patients previously evaluated as adherent and treatment resistant by directly observed therapy, thereby improving the accuracy of adherence evaluation. Registration URL: https://www.clinicaltrials.gov; unique identifier: NCT01673516.

Impact of medication adherence on the efficacy of Baroreflex activation therapy

Therapy adherence significantly determines the success of antihypertensive therapy, especially in patients with resistant hypertension. Our study investigates the impact of drug adherence on the efficacy of Baroreflex‐activation‐therapy (BAT). In this retrospective analysis, the authors measured blood pressure (BP) and antihypertensive medication adherence (by gas chromatography‐mass spectrometry [GC‐MS] urine analysis) before and 6 months after BAT initiation. Adherence was defined as detection of ≥80% intake of prescribed medication at the time of follow‐up. Response to BAT was defined as BP drop ≥5 mmHg in systolic 24 h‐ambulatory BP (ABP) after 6 months. Overall patients (n = 38) median medication adherence was low, but rose from 60% (IQR 25%–100%) to 75% (IQR 38%–100%; p = .0194). After 6 months of BAT, mean systolic and diastolic office BP (‐21 ± 25 mmHg and ‐9 ± 15 mmHg; p < .0001 and .0004) as well as 24 h‐ABP dropped significantly (‐9 ± 17 mmHg and ‐5 ± 12 mmHg; p = .0049 and .0280). After 6 months of BAT, 21 patients (60%) could be classified as responders. There was neither significant difference in mean office systolic (‐21 ± 23 mmHg vs. ‐21 ± 28 mmHg; p = .9581) nor in 24 h‐systolic ABP decrease (‐11 ± 19 mmHg vs. ‐7 ± 15 mmHg; p = .4450) comparing adherent and non‐adherent patients. Whereas Antihypertensive Therapeutic Index (ATI) was unchanged in non‐responders, it significantly decreased in responders (from 50 ± 16 to 46 ± 16; p = .0477). These data are the first to show that BAT‐initiation leads to a clear BP reduction independently of patients´ medication adherence. Response to BAT is associated with a significant lowering of ATI, which might contribute to an underestimation of BAT efficacy.

Opinions on hypertension care and therapy adherence at the healthcare provider and healthcare system level: a qualitative study in the Hague, Netherlands

OBJECTIVES

Hypertension is a common cause of cardiovascular morbidity and mortality. Although hypertension can be effectively controlled by blood pressure-lowering drugs, uncontrolled blood pressure is common despite use of these medications. One explanation is therapy non-adherence. Therapy non-adherence can be addressed at the individual level, the level of the healthcare provider and at the healthcare system level. Since the latter two levels are often overlooked, we wished to explore facilitators and barriers on each of these levels in relation to hypertension care for people with hypertension, with a specific focus on therapy adherence.

DESIGN

Qualitative study using focus groups of healthcare providers. Data were analysed using the theoretical domains framework (TDF) and the behaviour change wheel.

SETTING AND PARTICIPANTS

Participants were from a highly urbanised city environment (the Hague, Netherlands), and included nine primary care physicians, six practice nurses and five secondary care physicians involved in hypertension care.

RESULTS

Nine domains on the TDF were found to be relevant at the healthcare provider level ('knowledge', 'physical, cognitive and interpersonal skills', 'memory, attention and decision processes', 'professional, social role and identity', 'optimism', 'beliefs about consequences', 'intention', 'emotion' and 'social influences') and two domains ('resources' and 'goals') were found to be relevant at the system level. Facilitators for these domains were good interpersonal skills, paying attention to behavioural factors such as medication use, and the belief that treatment improves health outcomes. Barriers were related to time, interdisciplinary collaboration, technical and financial issues, availability of blood pressure devices and education of people with hypertension.

CONCLUSIONS

This study highlighted a need for better collaboration between primary and secondary care, for more team-based care including pharmacists and social workers, tools to improve interpersonal skills and more time for patient-healthcare provider communication.

Renal denervation for resistant hypertension

BACKGROUND

Resistant hypertension is highly prevalent among the general hypertensive population and the clinical management of this condition remains problematic. Different approaches, including a more intensified antihypertensive therapy, lifestyle modifications or both, have largely failed to improve patients' outcomes and to reduce cardiovascular and renal risk. As renal sympathetic hyperactivity is a major driver of resistant hypertension, in the last decade renal sympathetic ablation (renal denervation) has been proposed as a possible therapeutic alternative to treat this condition.

OBJECTIVES

We sought to evaluate the short- and long-term effects of renal denervation in individuals with resistant hypertension on clinical end points, including fatal and non-fatal cardiovascular events, all-cause mortality, hospital admissions, quality of life, blood pressure control, left ventricular hypertrophy, cardiovascular and metabolic profile and kidney function, as well as the potential adverse events related to the procedure.

SEARCH METHODS

For this updated review, the Cochrane Hypertension Information Specialist searched the following databases for randomised controlled trials up to 3 November 2020: Cochrane Hypertension's Specialised Register, CENTRAL (2020, Issue 11), Ovid MEDLINE, and Ovid Embase. The World Health Organization International Clinical Trials Registry Platform (via CENTRAL) and the US National Institutes of Health Ongoing Trials Register ClinicalTrials.gov were searched for ongoing trials. We also contacted authors of relevant papers regarding further published and unpublished work. The searches had no language restrictions.

SELECTION CRITERIA

We considered randomised controlled trials (RCTs) that compared renal denervation to standard therapy or sham procedure to treat resistant hypertension, without language restriction.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data and assessed study risk of bias. We summarised treatment effects on available clinical outcomes and adverse events using random-effects meta-analyses. We assessed heterogeneity in estimated treatment effects using Chi² and I² statistics. We calculated summary treatment estimates as a mean difference (MD) or standardised mean difference (SMD) for continuous outcomes, and a risk ratio (RR) for dichotomous outcomes, together with their 95% confidence intervals (CI). Certainty of evidence has been assessed using the GRADE approach.

MAIN RESULTS

We found 15 eligible studies (1416 participants). In four studies, renal denervation was compared to sham procedure; in the remaining studies, renal denervation was tested against standard or intensified antihypertensive therapy. Most studies had unclear or high risk of bias for allocation concealment and blinding.  When compared to control, there was low-certainty evidence that renal denervation had little or no effect on the risk of myocardial infarction (4 studies, 742 participants; RR 1.31, 95% CI 0.45 to 3.84), ischaemic stroke (5 studies, 892 participants; RR 0.98, 95% CI 0.33 to 2.95), unstable angina (3 studies, 270 participants; RR 0.51, 95% CI 0.09 to 2.89) or hospitalisation (3 studies, 743 participants; RR 1.24, 95% CI 0.50 to 3.11). Based on moderate-certainty evidence, renal denervation may reduce 24-hour ambulatory blood pressure monitoring (ABPM) systolic BP (9 studies, 1045 participants; MD -5.29 mmHg, 95% CI -10.46 to -0.13), ABPM diastolic BP (8 studies, 1004 participants; MD -3.75 mmHg, 95% CI -7.10 to -0.39) and office diastolic BP (8 studies, 1049 participants; MD -4.61 mmHg, 95% CI -8.23 to -0.99). Conversely, this procedure had little or no effect on office systolic BP (10 studies, 1090 participants; MD -5.92 mmHg, 95% CI -12.94 to 1.10). Moderate-certainty evidence suggested that renal denervation may not reduce serum creatinine (5 studies, 721 participants, MD 0.03 mg/dL, 95% CI -0.06 to 0.13) and may not increase the estimated glomerular filtration rate (eGFR) or creatinine clearance (6 studies, 822 participants; MD -2.56 mL/min, 95% CI -7.53 to 2.42).  AUTHORS' CONCLUSIONS: In patients with resistant hypertension, there is low-certainty evidence that renal denervation does not improve major cardiovascular outomes and renal function. Conversely, moderate-certainty evidence exists that it may improve 24h ABPM and diastolic office-measured BP. Future trials measuring patient-centred instead of surrogate outcomes, with longer follow-up periods, larger sample size and more standardised procedural methods are necessary to clarify the utility of this procedure in this population.

Monitoring Antihypertensive Medication Adherence by LC-MS/MS: Method Establishment and Clinical Application

ABSTRACT

Proper medication compliance is critical for the integrity of clinical practice, directly related to the success of clinical trials to evaluate both pharmacological and device-based therapies. Here, we established a liquid chromatography tandem mass spectrometry (LC-MS/MS) method to accurately detect 55 chemical entities in human urine sample, which accounting for the most commonly used 172 antihypertensive drugs in China. The established method had good accuracy, intra-day and inter-day precision for all analyses in both bench tests and validated in 21 hospitalized patients. We utilized this method to monitor and ensure drug compliance, and exclude the inferring impacts of medication compliance as a key confounder for our pivotal trial of a catheter-based, renal mapping and selective renal denervation to treat hypertension. It is found that in the urine samples from 92 consecutive subjects, 85 subjects (92.4%) were consistent with their prescriptions after 28 days run-in periods, 90 (97.8%) and 85 (95.5%) patients completely complied with their medications during the 3-month and 6-month follow-up period, respectively. Thus, using LC-MS/MS method with specificity, accuracy and precision, we ensured drug compliance of patients, excluded the key confounder of drug interferences and ensured the quality of our device-based clinical trial for treatment of hypertension.

Current Status and Future Perspectives of Renal Denervation

Despite the availability of numerous antihypertensive medications, hypertension treatment and control rates remain low, and uncontrolled hypertension is well-known to be one of the most important cardiovascular risk factors. Endovascular catheter-based renal denervation (RDN) has been developed to be a complementary or alternative treatment option for patients who cannot take medication, poor adherence, or have resistant hypertension despite the use of maximal doses of medications. Recently, several randomized trials for evaluating the efficacy and safety of second-generation RDN devices consistently show solid evidence for their blood pressure-lowering efficacy. This review summarizes the current evidence and future perspectives of RDN.

Catheter-based renal denervation (RDN) therapy, a new procedure that uses radiofrequency ablation to interrupt efferent and afferent renal sympathetic nerve fibers, is a complementary or alternative treatment to antihypertensive medications for optimal control of blood pressure (BP). Although several single-arm early proof-of-concept studies showed significant BP reduction, the largest sham-controlled study using the first-generation RDN device (SYMPLICITY HTN-3) failed to significantly reduce BP in patients with resistant hypertension who were taking the guideline-based combination of antihypertensive medications. Since then, new devices and techniques have been developed to improve the efficacy and safety of RDN procedures. Sham-controlled trials using second-generation RDN devices (radiofrequency- and ultrasound-based) have provided solid evidence for their BP-lowering efficacy with and without the use of concomitant antihypertensive medication. Moreover, the safety profile of RDN in several registries and clinical trials appears to be excellent. This review summarizes the current evidence for RDN and discusses its current issues, future trials, Asian perspectives, and potential roles in both hypertension and other morbidities.

Firibastat: A Novel Brain Aminopeptidase Inhibitor - A New Era of Antihypertensive therapy

Global incidence and prevalence of hypertension continues to increase and remains a significant challenge. The ever-increasing number of cases are due to comorbid conditions such as obesity and diabetes, as well as lifestyle indiscretions such as excessive salt intake. Hypertension, congestive heart failure, and kidney disease are all conditions resulting from abnormal Renin-Angiotensin-Aldosterone activation and adverse remodeling. Firibastat, a novel Brain Aminopeptidase inhibitor, may be able to help achieve blood pressure control in those with resistant hypertension. In this review article, we will discuss the biochemical pathway of firibastat and various trials assessing drug efficacy in animals and humans. This drug has the potential to curb the risk of uncontrolled hypertension and help improve long term cardiovascular morbidity and mortality.

Drug adherence and psychosocial characteristics of patients presenting with hypertensive urgency at the emergency department

OBJECTIVE

To identify potentially targetable psychosocial factors associated with nonadherence to prescribed antihypertensive medications in patients presenting with hypertensive urgencies at an emergency department.

METHODS

This prospective study included patients treated with antihypertensive drugs who presented with hypertensive urgencies (SBP ≥180 mmHg and/or DBP ≥110 mmHg) at the emergency department of a tertiary referral clinic between April 2018 and April 2019. Health literacy was assessed using the Newest Vital Sign test. The Hospital Anxiety and Depression Scale (HADS) was used to quantify symptoms of anxiety and depression. Patients were classified nonadherent if less than 80% of the prescribed antihypertensive drugs were detectable in urine or plasma using liquid chromatography-high-resolution mass spectrometry.

RESULTS

A total of 104 patients (62% women) presenting with hypertensive urgencies with a median SBP of 200 mmHg (IQR 190-212) and DBP of 97.5 mmHg (IQR 87-104) were included. Twenty-five patients (24%) were nonadherent to their antihypertensive medication. Nonadherent patients were more often men (66 versus 23%, P = 0.039), prescribed higher numbers of antihypertensive drugs (median 3, IQR 3-4 versus 2, IQR 1-3; P < 0.001), and more often treated with calcium channel blockers (76 versus 25%; P < 0.001) and/or diuretics (64 versus 40%; P = 0.030). There was no difference in health literacy (P = 0.904) or the scores on the HADS subscales for depression (P = 0.319) and anxiety (P = 0.529) between adherent and nonadherent patients.

CONCLUSION

Male sex, higher numbers of antihypertensive drugs, and treatment with diuretics and/or calcium channel blockers were associated with nonadherence. We did not identify a specific psychosocial characteristic associated with nonadherence.

Renal Denervation for Uncontrolled and Resistant Hypertension: Systematic Review and Network Meta-Analysis of Randomized Trials

Comparative efficacy and safety of renal denervation (RDN) interventions for uncontrolled (UH) and resistant hypertension (RH) is unknown. We assessed the comparative efficacy and safety of existing RDN interventions for UH and RH. Six search engines were searched up to 1 May 2020. Primary outcomes were mean 24-h ambulatory and office systolic blood pressure (SBP). Secondary outcomes were mean 24-h ambulatory and office diastolic blood pressure (DBP), clinical outcomes, and serious adverse events. Frequentist random-effects network meta-analyses were used to evaluate effects of RDN interventions. Twenty randomized controlled trials (RCTs) (n = 2152) were included, 15 in RH (n = 1544) and five in UH (n = 608). Intervention arms included radiofrequency (RF) in main renal artery (MRA) (n = 10), RF in MRA and branches (n = 4), RF in MRA+ antihypertensive therapy (AHT) (n = 5), ultrasound (US) in MRA (n = 3), sham (n = 8), and AHT (n = 9). RF in MRA and branches ranked as the best treatment to reduce 24-h ambulatory, daytime, and nighttime SBP and DBP versus other interventions (p-scores: 0.83 to 0.97); significant blood pressure effects were found versus sham or AHT. RF in MRA+AHT was the best treatment to reduce office SBP and DBP (p-scores: 0.84 and 0.90, respectively). RF in MRA and branches was the most efficacious versus other interventions to reduce 24-h ambulatory SBP and DBP in UH or RH.

Optimizing identification of resistant hypertension: Computable phenotype development and validation

PURPOSE

Computable phenotypes are constructed to utilize data within the electronic health record (EHR) to identify patients with specific characteristics; a necessary step for researching a complex disease state. We developed computable phenotypes for resistant hypertension (RHTN) and stable controlled hypertension (HTN) based on the National Patient-Centered Clinical Research Network (PCORnet) common data model (CDM). The computable phenotypes were validated through manual chart review.

METHODS

We adapted and refined existing computable phenotype algorithms for RHTN and stable controlled HTN to the PCORnet CDM in an adult HTN population from the OneFlorida Clinical Research Consortium (2015-2017). Two independent reviewers validated the computable phenotypes through manual chart review of 425 patient records. We assessed precision of our computable phenotypes through positive predictive value (PPV) and test validity through interrater reliability (IRR).

RESULTS

Among the 156 730 HTN patients in our final dataset, the final computable phenotype algorithms identified 24 926 patients with RHTN and 19 100 with stable controlled HTN. The PPV for RHTN in patients randomly selected for validation of the final algorithm was 99.1% (n = 113, CI: 95.2%-99.9%). The PPV for stable controlled HTN in patients randomly selected for validation of the final algorithm was 96.5% (n = 113, CI: 91.2%-99.0%). IRR analysis revealed a raw percent agreement of 91% (152/167) with Cohen's kappa statistic = 0.87.

CONCLUSIONS

We constructed and validated a RHTN computable phenotype algorithm and a stable controlled HTN computable phenotype algorithm. Both algorithms are based on the PCORnet CDM, allowing for future application to epidemiological and drug utilization based research.

Device-Based Neuromodulation for Resistant Hypertension Therapy

Despite availability of effective drugs for hypertension therapy, significant numbers of hypertensive patients fail to achieve recommended blood pressure levels on ≥3 antihypertensive drugs of different classes. These individuals have a high prevalence of adverse cardiovascular events and are defined as having resistant hypertension (RHT) although nonadherence to prescribed antihypertensive medications is common in patients with apparent RHT. Furthermore, apparent and true RHT often display increased sympathetic activity. Based on these findings, technology was developed to treat RHT by suppressing sympathetic activity with electrical stimulation of the carotid baroreflex and catheter-based renal denervation (RDN). Over the last 15 years, experimental and clinical studies have provided better understanding of the physiological mechanisms that account for blood pressure lowering with baroreflex activation and RDN and, in so doing, have provided insight into which patients in this heterogeneous hypertensive population are most likely to respond favorably to these device-based therapies. Experimental studies have also played a role in modifying device technology after early clinical trials failed to meet key endpoints for safety and efficacy. At the same time, these studies have exposed potential differences between baroreflex activation and RDN and common challenges that will likely impact antihypertensive treatment and clinical outcomes in patients with RHT. In this review, we emphasize physiological studies that provide mechanistic insights into blood pressure lowering with baroreflex activation and RDN in the context of progression of clinical studies, which are now at a critical point in determining their fate in RHT management.

Telemonitoring and remote counseling in hypertensive patients. Looking for new ways to do old jobs

XXI century emphasized humanity to embrace the digital era after a reality of Third and Fourth Industrial Revolutions, nowadays dictating new terms of social networking. It is expected that information and communication technologies integrated with value-based medicine will significantly impact healthcare delivery to tremendous number of patients with socially important noncommunicable diseases. Cardiovascular illnesses comprise the greatest part of such pathologies. Hypertension (HTN) being the most prevalent cardiovascular disease is also the key modifiable cardiovascular risk factor yet seems to be an attractive target for both value-based concept and telehealth interventions. Present review addresses up-to-date science on telehealth, sets out the main well-known, but yet unsolved challenges in management of HTN along with the new approaches involving telemedicine programs, digital health outlooks. The main barriers of telehealth implementation are also considered along with the possible solutions.

New data, new studies, new hopes for renal denervation in patients with uncontrolled hypertension

Background

following the publication of SYMPLICITY HTN-3 the field of renal of denervation was put on hold. Although SYMPLICITY HTN-3 was well-designed and sham-controlled trial it failed to show any meaningful reduction in office or 24 h ambulatory blood pressure. The procedure was however safe and allowed research to continue. Although several pitfalls of the study have been pointed out, incomplete renal denervation was also implicated. Since then, a great deal of basic and clinical research took place and will be briefly commented on in this article.

Methods and results

Before and after SYMPLICITY-HTN-3, numerous uncontrolled, single or unblinded studies have shown substantial office BP reduction ranging from -7.7 to -32 mmHg and ambulatory BP ranging from -2.2 to 10.2 mmHg. Average weighted office systolic BP reduction was -20.8 mmHg and weighted average 24 h ambulatory BPM reduction was -7.8 mmHg. National and international registries have shown similar BP reductions, but results remained unconvincing due to lack of reliable sham controls. In recent years, 5 well-designed sham - controlled studies (beyond, SYMPLICITY-HTN-3) have been published. Of those studies two were single center and three were multicenter international studies. Four studies used single tip or multi-electrode, radiofrequency catheters and one used focused ultrasound. The three multicenter studies reported positive-placebo subtracted results and established BP reductions measured both in the office and by ambulatory monitoring. No serious adverse events were reported.

Conclusions

It can therefore be concluded that the latest sham controlled studies established efficacy and safety of renal denervation.

Joint UK societies' 2019 consensus statement on renal denervation

Improved and durable control of hypertension is a global priority for healthcare providers and policymakers. There are several lifestyle measures that are proven to result in improved blood pressure (BP) control. Moreover, there is incontrovertible evidence from large scale randomised controlled trials (RCTs) that antihypertensive drugs lower BP safely and effectively in the long-term resulting in substantial reduction in cardiovascular morbidity and mortality. Importantly, however, evidence is accumulating to suggest that patients neither sustain long-term healthy behaviours nor adhere to lifelong drug treatment regimens and thus alternative measures to control hypertension warrant further investigation. Endovascular renal denervation (RDN) appears to hold some promise as a non-pharmacological approach to lowering BP and achieves renal sympathectomy using either radiofrequency energy or ultrasound-based approaches. This treatment modality has been evaluated in clinical trials in humans since 2009 but initial studies were compromised by being non-randomised, without sham control and small in size. Subsequently, clinical trial design and rigour of execution has been greatly improved resulting in recent sham-controlled RCTs that demonstrate short-term reduction in ambulatory BP without any significant safety concerns in both medication-naïve and medication-treated hypertensive patients. Despite this, the joint UK societies still feel that further evaluation of this therapy is warranted and that RDN should not be offered to patients outside of the context of clinical trials. This document reviews the updated evidence since our last consensus statement from 2014 and provides a research agenda for future clinical studies.

Effect of Catheter-Based Renal Denervation on Uncontrolled Hypertension: A Systematic Review and Meta-analysis

OBJECTIVE

To assess the efficacy and safety of catheter-based renal denervation (RDN) for the treatment of uncontrolled hypertension by conducting a systematic review and a meta-analysis.

METHODS

The Medline, Cochrane Library, and Embase databases were searched for clinical studies between January 1, 2009, and July 16, 2018. Studies that evaluated the effect of RDN on uncontrolled hypertension were identified. The primary endpoints were changes in 24-hour ambulatory systolic blood pressure (BP) and office systolic BP. The secondary endpoints included changes in 24-hour ambulatory diastolic BP, office diastolic BP, and major adverse events.

RESULTS

After a literature search and detailed evaluation, 12 randomized controlled trials with a total of 1539 individuals were included in the quantitative analysis. Pooled analyses indicated that RDN was associated with a significantly greater reduction of 24-hour systolic BP (mean difference [MD], -4.02 mm Hg; 95% CI, -5.49 to -2.56; P<.001) and office systolic BP (MD, -8.93 mm Hg; 95% CI, -14.03 to -3.83; P<.001) than controls. Similarly, RDN significantly reduced 24-hour diastolic BP (MD, -2.05 mm Hg; 95% CI, -3.05 to -1.05; P<.001) and office diastolic BP (MD, -4.49 mm Hg; 95% CI, -6.46 to -2.52; P<.001). RDN was not associated with an increased risk of major adverse events (relative risk, 1.06; 95% CI, 0.72 to 1.57; P=.76).

CONCLUSIONS

Catheter-based RDN was associated with a significant BP-lowering benefit without increasing major adverse events.

Is renal denervation still a treatment option in cardiovascular disease?

The role of renal sympathetic denervation (RDN) has been the topic of ongoing debate ever since the impressive initial results. The rationale of RDN is strong and supported by non-clinical studies, which lies in uncoupling the autonomic nervous crosstalk between the kidneys and the central nervous system. Since we know that cardiovascular diseases, such as hypertension, atrial, ventricular arrhythmias and heart failure (HF) are related to sympathetic (over)activity, modulation of the renal nerve activity appears to be a reasonable and attractive therapeutic target in these patients. This review will focus on the existing evidence and potential future perspectives for RDN as treatment option in cardiovascular disease.

Screening of cardiovascular agents in plasma with LC-MS/MS: A valuable tool for objective drug adherence assessment

Adherence to cardiovascular preventive agents is important to prevent short and long term cardiovascular events. Recently, qualitatively compound screening using liquid chromatography-tandem mass spectrometry (LC-MS/MS) has gained interest for drug adherence assessment in patients at high risk of cardiovascular events. Therefore, we developed and tested an assay including 52 compounds and metabolites, covering over 95% of the antihypertensive and antithrombotic agents available worldwide. Trichloroacetic acid was used as simple and fast method for protein precipitation. The assay was validated for lower limit of quantification (LLOQ), linearity, stability for freeze/thaw, room temperature, autosampler and matrix effects. The LLOQ for each compound was targeted under the population trough concentration (PTC) as reported in literature to assure high sensitivity for adherence detection. This was accomplished for 50 of 52 compounds with a LLOQ equal or lower compared to the PTC. Linearity was confirmed for all compounds (r² > 0.995), except for acetylsalicylic acid (r² = 0.991). For room temperature stability, 12 compounds showed degradation over 20% after 20 h. 3 compounds suffer from matrix effect with recoveries < 50%. After analytical validation, blood samples from 91 patients with difficult-to-treat hypertension were analyzed. Patients were unaware of adherence assessment. Adherence varied largely per agent and per concentration ratio (CR) (ratio of the detected concentration with LC-MS/MS and the PTC) cut-off value. Additionally, stratification by adherence group showed that the percentage of patients classified as non-adherent increased from 6.6% for qualitative analysis (pos/neg) to 19.8% for a CR cut-off of 0.5. The data imply that using the CR cut off values has a significant and relevant effect on patient adherence classification.

Renal Denervation for Resistant Hypertension in the contemporary era: A Systematic Review and Meta-analysis

Renal denervation (RDN) is a catheter-based ablation procedure designed to treat resistant hypertension (RH). The objective of our study is to determine the effect of RDN on blood pressure and renal function in patients with RH in comparison to medical therapy alone. We performed an extensive literature search for randomized control trials (RCT) reporting office and 24 hr. blood pressure changes and estimated glomerular filtration rate (eGFR) at baseline and 6 months. We calculated a weighted standardized mean difference of blood pressure and renal outcomes between RDN and control groups using random effects models. Our search yielded 608 studies of which we included 15 studies for the final analysis. A total of 857 patients were treated with RDN and 616 patients treated with medical therapy ± sham procedure. Only 5 studies were double-blinded RCT with sham control. The adjusted standardized mean difference in the change in office based systolic and diastolic pressures (p = 0.18; p = 0.14); 24 hr. systolic and diastolic pressures (p = 0.20; p = 0.18); and eGFR (p = 0.20) from baseline to 6 months is statistically insignificant with significant heterogeneity. Subgroup analysis showed that among sham controlled trials, 24 hr. systolic blood pressure showed a modest but statistically significant benefit favoring renal denervation in patients with RH. Our meta-analysis of 15 RCTs showed no significant benefit of RDN on blood pressure control in patients with resistant hypertension. Subgroup analysis of sham control studies showed a modest benefit in 24 hr. systolic blood pressure at 6 months with RDN.

Adherence to antihypertensive drug treatment in patients with apparently treatment-resistant hypertension in the INSPiRED pilot study

PURPOSE

Drug adherence may be a major problem in the therapy of hypertension and in the diagnosis of therapy resistance. Adherence can be assessed by indirect methods or by direct methods like drug detection in urine with liquid chromatography-mass spectrometric methods.

MATERIALS AND METHODS

The current analysis included patients with apparently treatment- resistant hypertension (TRH) referred for renal denervation (RDN) and included in the the INSPiRED pilot trial (NCT01505010). Adherence was repeatedly assessed by toxicological urine analysis over a time range of up to 17 months in a total of 18 patients.

RESULTS

In the first urine samples of 18 patients the adherence rate (percentage of number of detected vs. prescribed medical drugs) ranged from 0 to 100% with a median of 73.2%. In further urine samples collected during the following up to 17 months every individual patient exhibited considerable changes in the adherence rate, neither a constancy nor a tendency could be deduced.

CONCLUSIONS

Urine analysis results exhibit variation over time and an assessment at a certain time point cannot be regarded as representative or predictor for future behavior. Therefore, it appears necessary to perform drug adherence testing repeatedly over time.

Renal Denervation in High-risk Patients with Hypertension

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A novel integrated care concept (NICC) versus standard care in the treatment of chronic cardiovascular diseases: protocol for the randomized controlled trial CardioCare MV

Background

Cardiovascular diseases are the major cause of death globally and represent a major economic burden on health care systems. Positive effects of disease management programs have been shown for patients with heart failure (HF). Remote monitoring and telemonitoring with active intervention are beneficial in atrial fibrillation (AF) and therapy-resistant hypertension (TRH), respectively. For these patients, we have developed a novel integrated care concept (NICC) which combines telemedicine with intensive support by a care center, including a call center, an integrated care network including inpatient and outpatient care providers and guideline therapy for patients.

Methods

The aim of the study is to demonstrate the superiority of NICC over guideline therapy alone. The trial is designed as open-label, bi-center, parallel-group design with two groups and a blinded observer. Patients will be included if they are either inpatients or if they are referred to the outpatient clinic of the hospitals by their treating physician. Randomization will be done individually with stratification by cardiovascular disease (AF, HF, TRH), center and admission type. Primary endpoints are based on the 1-year observation period after randomization. The first primary endpoint is the composite endpoint consisting of mortality, stroke and myocardial infarction. The number of hospitalizations form the second primary endpoint. The third primary endpoint is identical to the first primary endpoint plus cardiac decompensation. Adjustments for multiple testing are done using a fall-back strategy. Secondary endpoints include patient adherence, health care costs, quality of life, and safety. A sample size of 2930 gives 80% power at the two-sided 2.5% test level for the first primary endpoint. The power for the second primary endpoint is 99.8% at this sample size, and it is 80% with 1086 patients.

Discussion

This study will inform care providers whether quality of care can be improved by an integrated care concept providing telemedicine through a round-the-clock call center approach. We expect that cost of the NICC will be lower than standard care because of reduced hospitalizations. If the study has a positive result, NICC is planned to be immediately rolled out in the federal state of Mecklenburg-West Pomerania and other federal states in Germany. The trial will also guide additional research to disentangle the effects of this complex intervention.

Trial registration

DRKS, ID: DRKS00013124. Registered on 5 October 2017;

ClinicalTrials.gov, ID: NCT03317951. Registered on 17 October 2017.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2502-1) contains supplementary material, which is available to authorized users.

Endovascular baroreflex amplification for resistant hypertension: a safety and proof-of-principle clinical study

BACKGROUND

Carotid baroreflex activation lowers blood pressure and might have potential application for the treatment of resistant hypertension. We did a proof-of-principle trial with a novel endovascular baroreceptor amplification device, MobiusHD (Vascular Dynamics, Mountain View, CA, USA), in patients with resistant hypertension.

METHODS

CALM-FIM_EUR was a prospective, first-in-human, open-label study done at six European centres. Eligible patients were adults with resistant hypertension (office systolic blood pressure ≥160 mm Hg despite taking at least three antihypertensive agents, including a diuretic). MobiusHD devices were implanted unilaterally in the internal carotid artery. The primary endpoint was the incidence of serious adverse events at 6 months. Secondary endpoints included changes in office and 24 h ambulatory blood pressure. This trial is registered with ClinicalTrials.gov, number NCT01911897.

FINDINGS

Between December, 2013, and February, 2016, 30 patients were enrolled and underwent successful implantation. Mean age was 52 years (SD 12), 15 patients (50%) were men, and mean antihypertensive use was 4·4 drugs (1·4). Mean office blood pressure was 184/109 mm Hg (18/14) at baseline and was reduced by 24/12 mm Hg (13-34/6-18) at 6 months (p=0·0003 for systolic and p=0·0001 diastolic blood pressure). Mean baseline 24 h ambulatory blood pressure was 166/100 mm Hg (17/14) at baseline and was reduced by 21/12 mm Hg (14-29/7-16) at 6 months (p<0·0001 for systolic and diastolic blood pressure). Five serious adverse events had occurred in four patients (13%) at 6 months: hypotension (n=2), worsening hypertension (n=1), intermittent claudication (n=1) and wound infection (n=1).

INTERPRETATION

In patients with resistant hypertension, endovascular baroreceptor amplification with the MobiusHD device substantially lowered blood pressure with an acceptable safety profile. Randomised, double-blind, sham-controlled trials are warranted to investigate the use of this treatment further.

FUNDING

Vascular Dynamics.

The Treatment In Morning versus Evening (TIME) study: analysis of recruitment, follow-up and retention rates post-recruitment

BACKGROUND

The use of information technology (IT) is now the preferred method of capturing and storing clinical research data. The Treatment In Morning versus Evening (TIME) study predominantly uses electronic data capture and IT to compare morning dosing of hypertensive medication against evening dosing. Registration, consent, participant demographics and follow-up data are all captured via the study website. The aim of this article is to assess the success of the TIME methodology compared with similar studies.

METHODS

To assess the TIME study, published literature on similar clinical trials was reviewed and compared against TIME recruitment, follow-up and email interaction data.

RESULTS

The TIME website registered 31,695 individuals, 21,116 of whom were randomised. Recruitment cost per randomised participant varied by strategy: £17.40 by GP practice, £3.08 by UK Biobank and £58.82 for GoShare. Twelve-month follow-up retention rates were 96%. A total of 1089 participants have withdrawn from their assigned time of dosing, 2% of whom have declined follow-up by record linkage or further contact. When the TIME data are compared with similar study data, study recruitment is very successful. However, TIME suffers difficulties with participant follow-up and withdrawal rates similar to those of conventional studies.

CONCLUSIONS

The TIME study has been successful in recruitment. Follow-up, retention rates and withdrawal rates are all acceptable, but ongoing work is required to ensure participants remain engaged with the study. Various recruitment strategies are necessary, and all viable options should be encouraged to maintain participant engagement throughout the life of studies using IT.

Catheter-based renal denervation in patients with uncontrolled hypertension in the absence of antihypertensive medications (SPYRAL HTN-OFF MED): a randomised, sham-controlled, proof-of-concept trial

BACKGROUND

Previous randomised renal denervation studies did not show consistent efficacy in reducing blood pressure. The objective of our study was to evaluate the effect of renal denervation on blood pressure in the absence of antihypertensive medications.

METHODS

SPYRAL HTN-OFF MED was a multicentre, international, single-blind, randomised, sham-controlled, proof-of-concept trial. Patients were enrolled at 21 centres in the USA, Europe, Japan, and Australia. Eligible patients were drug-naive or discontinued their antihypertensive medications. Patients with an office systolic blood pressure (SBP) of 150 mm Hg or greater and less than 180 mm Hg, office diastolic blood pressure (DBP) of 90 mm Hg or greater, and a mean 24-h ambulatory SBP of 140 mm Hg or greater and less than 170 mm Hg at second screening underwent renal angiography and were randomly assigned to renal denervation or sham control. Patients, caregivers, and those assessing blood pressure were blinded to randomisation assignments. The primary endpoint, change in 24-h blood pressure at 3 months, was compared between groups. Drug surveillance was done to ensure patient compliance with absence of antihypertensive medication. The primary analysis was done in the intention-to-treat population. Safety events were assessed at 3 months. This study is registered with ClinicalTrials.gov, number NCT02439749.

FINDINGS

Between June 25, 2015, and Jan 30, 2017, 353 patients were screened. 80 patients were randomly assigned to renal denervation (n=38) or sham control (n=42) and followed up for 3 months. Office and 24-h ambulatory blood pressure decreased significantly from baseline to 3 months in the renal denervation group: 24-h SBP -5·5 mm Hg (95% CI -9·1 to -2·0; p=0·0031), 24-h DBP -4·8 mm Hg (-7·0 to -2·6; p<0·0001), office SBP -10·0 mm Hg (-15·1 to -4·9; p=0·0004), and office DBP -5·3 mm Hg (-7·8 to -2·7; p=0·0002). No significant changes were seen in the sham-control group: 24-h SBP -0·5 mm Hg (95% CI -3·9 to 2·9; p=0·7644), 24-h DBP -0·4 mm Hg (-2·2 to 1·4; p=0·6448), office SBP -2·3 mm Hg (-6·1 to 1·6; p=0·2381), and office DBP -0·3 mm Hg (-2·9 to 2·2; p=0·8052). The mean difference between the groups favoured renal denervation for 3-month change in both office and 24-h blood pressure from baseline: 24-h SBP -5·0 mm Hg (95% CI -9·9 to -0·2; p=0·0414), 24-h DBP -4·4 mm Hg (-7·2 to -1·6; p=0·0024), office SBP -7·7 mm Hg (-14·0 to -1·5; p=0·0155), and office DBP -4·9 mm Hg (-8·5 to -1·4; p=0·0077). Baseline-adjusted analyses showed similar findings. There were no major adverse events in either group.

INTERPRETATION

Results from SPYRAL HTN-OFF MED provide biological proof of principle for the blood-pressure-lowering efficacy of renal denervation.

FUNDING

Medtronic.

Medication adherence in patients with apparent resistant hypertension: findings from the SYMPATHY trial

AIMS

Hypertension is only controlled in approximately 35% of the patients, which could be partially due to nonadherence. Recently, bioanalytical assessment of adherence to blood pressure (BP) lowering drugs has gaining interest. Our aim was to explore possible determinants of nonadherence in treatment resistant hypertension, assessed by objective screening for antihypertensive agents in serum. The secondary aim was to study the effect of adherence on the change in BP.

METHODS

This project was a substudy of SYMPATHY; an open-label randomized-controlled trial to assess the effect of renal denervation on BP 6 months after treatment compared to usual care in patients with resistant hypertension. Stored serum samples were screened for antihypertensive agents to assess adherence at baseline and 6 months after intervention, using liquid chromatography-tandem mass spectrometry. Office and 24-h BP were measured on the same day as blood was sampled. Patients and physicians were unaware of adherence measurements.

RESULTS

Ninety-eight baseline and 83 6-month samples were available for analysis. Sixty-eight percent [95% confidence interval (CI) 59-78%] of the patients was nonadherent (n = 67). For every onw pill more prescribed, 0.785 [95%CI 0.529-0.891] prescribed pill was less detected in blood. A decrease of one pill in adherence between baseline and 6 months was associated with a significant rise in office systolic BP of 4 (95%CI 0.230-8.932) mmHg.

CONCLUSION

Objective measurement of BP lowering drugs in serum, as a tool to assess adherence, showed that nonadherence was very common in patients with apparent resistant hypertension. Furthermore, the assessment results were related to (changes in) blood pressure. Our findings provide direct and objective methodology to help the physician to understand and to improve the condition of apparent resistant hypertension.

Salt intake and blood pressure response to percutaneous renal denervation in resistant hypertension

The effect of lowering sympathetic nerve activity by renal denervation (RDN) is highly variable. With the exception of office systolic blood pressure (BP), predictors of the BP-lowering effect have not been identified. Because dietary sodium intake influences sympathetic drive, and, conversely, sympathetic activity influences salt sensitivity in hypertension, we investigated 24-hour urinary sodium excretion in participants of the SYMPATHY trial. SYMPATHY investigated RDN in patients with resistant hypertension. Both 24-hour ambulatory and office BP measurements were end points. No relationship was found for baseline sodium excretion and change in BP 6 months after RDN in multivariable-adjusted regression analysis. Change in the salt intake-measured BP relationships at 6 months vs baseline was used as a measure for salt sensitivity. BP was 8 mm Hg lower with similar salt intake after RDN, suggesting a decrease in salt sensitivity. However, the change was similar in the control group, and thus not attributable to RDN.

Prevalence and clinical characteristics of apparent therapy-resistant hypertension in patients with cardiovascular disease: a cross-sectional cohort study in secondary care

OBJECTIVES

Our aim was to investigate the prevalence of apparent therapy-resistant hypertension (aTRH) in patients with clinical manifest cardiovascular disease (CVD), and to study clinical characteristics related to aTRH in this population.

SETTING

The SMART (Second Manifestations of ARTerial disease) study is a large, single-centre cohort study in secondary care.

PARTICIPANTS

Office blood pressure (BP) at inclusion was used to evaluate BP control in 6191 hypertensive patients with clinical manifest (cardio)vascular disease. Therapy-resistant hypertension was defined as BP ≥140/90 mm Hg despite use of antihypertensive drugs from ≥3 drug classes including a diuretic or use of ≥4 antihypertensive drugs irrespective of BP. Logistic regression analysis was used to explore the relationship between clinical characteristics measured at baseline and presence of aTRH.

RESULTS

The prevalence of aTRH was 9.1% (95% CI 8.4 to 9.8). Prevalence increased with age and when albuminuria was present and was higher in patients with lower estimated glomerular filtration rate (eGFR). Presence of aTRH was related to diabetes, female sex, duration and multiple locations of vascular disease, body mass index and waist circumference. Carotid intima-media thickness was higher (0.99±0.28 vs 0.93±0.28 mm) and ankle-brachial index lower (1.07±0.20 vs 1.10±0.19) in patients with aTRH compared with patients without aTRH.

CONCLUSION

aTRH is prevalent in patients with clinical manifest CVD and is related to clinical factors known to be related with increased vascular risk, and with lower eGFR.