A novel, proof-of-concept radiofrequency renal denervation strategy to improve procedural efficiency: 12-month results from the SPYRAL DYSTAL pilot study.

BACKGROUND: Catheter-based renal sympathetic denervation (RDN) reduced blood pressure (BP) in multiple randomized sham-controlled trials of patients with uncontrolled hypertension (HTN). We tested proof-of-concept for a more selective treatment strategy, exclusively targeting these areas to improve the efficiency of the procedure. METHODS: The SPYRAL DYSTAL Pilot study was designed to mirror the SPYRAL HTN-OFF MED Pivotal study, enabling comparison with a propensity score adjusted active-control group. Patients were antihypertensive medication-free for one month before undergoing BP assessment. Those with office BP of 150-180/>90 mmHg and with an ambulatory systolic BP of 140-170 mmHg were selected to undergo open label treatment, delivering energy only to the distal main renal arteries and first order branches. Patients from DYSTAL were compared with patients who underwent maximized RF RDN treatment in the prior randomized OFF MED trial at 3 months. After 3 months, patients resumed antihypertensive medications as indicated. Safety and efficacy outcomes were assessed post hoc through 12 months. RESULTS: The SPYRAL DYSTAL Pilot study treated 56 HTN patients. Baseline office systolic BP (OSBP) and 24-h ambulatory systolic BP (ASBP) were similar between DYSTAL and OFF MED patient groups. The number of ablations (32.3 ± 8.0 vs 46.6 ± 15.3, p < 0.001), procedure time (67 ± 21 min vs 99 ± 36 min; p < 0.001), and contrast volume (173 ± 77 cc vs 208 ± 96 cc; p = 0.014) were significantly lower with the simplified treatment strategy. OSBP and ASBP changes compared with baseline were -9.0 and -1.4 mmHg at 3 months, -20.3 and -13.9 mmHg at 6 months, and -20.3 and -16.6 mmHg at 12 months, respectively. During the medication up-titration phase, BP reductions among DYSTAL patients were similar to reductions observed in OFF MED through 12 months, with comparable number of drugs (1.4 and 1.5 medications, respectively (P=NS)). Two adverse events related to guidewire placement were reported. CONCLUSION: In this pilot study, focusing ablation treatment on the distal main and proximal branch renal arteries was performed, resulting in fewer RF lesions, and reduced contrast volume and procedure time. Whether BP reductions are similar between a selective vs. maximized RDN approach requires further prospective study.

Impact of Antihypertensive Medication Changes After Renal Denervation Among Different Patient Groups: SPYRAL HTN-ON MED.

BACKGROUND: The SPYRAL HTN-ON MED (Global Clinical Study of Renal Denervation With the Symplicity Spyral Multi-electrode Renal Denervation System in Patients With Uncontrolled Hypertension in the Absence of Antihypertensive Medications)trial showed significant office and nighttime systolic blood pressure (BP) reductions in patients with hypertension following renal denervation (RDN) compared with sham-control patients, despite similar 24-hour BP reductions. We compared antihypertensive medication and BP changes among prespecified subpopulations. METHODS: The multicenter, randomized, sham-controlled, blinded SPYRAL HTN-ON MED trial (n=337) evaluated BP changes after RDN compared with a sham procedure in patients with hypertension prescribed 1 to 3 antihypertensive drugs. Most patients (n=187; 54%) were enrolled outside the United States, while 156 (46%) US patients were enrolled, including 60 (18%) Black Americans. RESULTS: Changes in detected antihypertensive drugs were similar between RDN and sham group patients in the outside US cohort, while drug increases were significantly more common in the US sham group compared with the RDN group. Patients from outside the United States showed significant reductions in office and 24-hour mean systolic BP at 6 months compared with the sham group, whereas BP changes were similar between RDN and sham in the US cohort. Within the US patient cohort, Black Americans in the sham control group had significant increases in medication burden from baseline through 6 months (P=0.003) but not in the RDN group (P=0.44). CONCLUSIONS: Patients enrolled outside the United States had minimal antihypertensive medication changes between treatment groups and had significant office and 24-hour BP reductions compared with the sham group. Increased antihypertensive drug burden in the US sham cohort, especially among Black Americans, may have diluted the treatment effect in the combined trial population. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02439775.

Prognostic utility of rhythmic components in 24-h ambulatory blood pressure monitoring for the risk stratification of chronic kidney disease patients with cardiovascular co-morbidity.

Chronic kidney disease (CKD) represents a significant global burden. Hypertension is a modifiable risk factor for rapid progression of CKD. We extend the risk stratification by introducing the non-parametric determination of rhythmic components in 24-h profiles of ambulatory blood pressure monitoring (ABPM) in the Chronic Renal Insufficiency Cohort (CRIC) and the African American Study for Kidney Disease and Hypertension (AASK) cohort using Cox proportional hazards models. We find that rhythmic profiling of BP through JTK_CYCLE analysis identifies subgroups of CRIC participants that were more likely to die due to cardiovascular causes. While our fully adjusted model shows a trend towards a significant association between absent cyclic components and cardiovascular death in the full CRIC cohort (HR: 1.71,95% CI: 0.99-2.97, p = 0.056), CRIC participants with a history of cardiovascular disease (CVD) and absent cyclic components in their BP profile had at any time a 3.4-times higher risk of cardiovascular death than CVD patients with cyclic components present in their BP profile (HR: 3.37, 95% CI: 1.45-7.87, p = 0.005). This increased risk was not explained by the dipping or non-dipping pattern in ABPM. Due to the large differences in patient characteristics, the results do not replicate in the AASK cohort. This study suggests rhythmic blood pressure components as a potential novel biomarker to unmask excess risk among CKD patients with prior cardiovascular disease.

Orthostatic hypotension, orthostatic hypertension, and ambulatory blood pressure in patients with chronic kidney disease in CRIC.

BACKGROUND: Orthostatic changes in blood pressure (BP), either orthostatic hypotension or orthostatic hypertension (OHTN), are common among patients with chronic kidney disease. Whether they are associated with unique out-of-office BP phenotypes is unknown. METHODS: CRIC is a prospective, multicenter, observational cohort study of participants with CKD. BP measured at 2 min after standing and ambulatory BP monitoring (ABPM) were obtained on 1386 participants. Orthostatic hypotension was defined as a 20 mmHg drop in SBP or 10 mmHg drop in DBP when changing from seated to standing positions. Systolic and diastolic night-to-day ratio was also calculated. OHTN was defined as a 20 or 10 mmHg rise in SBP or DBP when changing from a seated to a standing position. White-coat effect (WCE) was defined as seated minus daytime ambulatory BP. RESULTS: Of the 1386 participants (age: 58 ±â€Š10 years, 44% female, 39% black), 68 had orthostatic hypotension and 153 had OHTN. Postural reduction in SBP or DBP was positively associated with greater systolic and diastolic WCE and systolic and diastolic night-to-day ratio. Orthostatic hypotension was positively associated with diastolic WCE (ß = 3 [0.2, 5.9]). Diastolic OHTN was negatively associated with systolic WCE (ß = -4 [-7.2, -0.5]) and diastolic WCE (ß = -6 [-8.1, -4.2]). CONCLUSION: Postural change in BP was associated with WCE and night-to-day-ratio. Orthostatic hypotension was positively associated with WCE and OHTN was negatively associated with WCE. These findings strengthen observations that postural changes in BP may associate with distinct BP patterns throughout the day. These observations are informative for subsequent research tailoring orthostatic hypotension and OHTN treatment to specific BP phenotypes.

How New Developments in Pharmacology Receptor Theory Are Changing (Our Understanding of) Hypertension Therapy.

BACKGROUND: Many hypertension therapeutics were developed prior to major advances in drug receptor theory. Moreover, newer drugs may take advantage of some of the newly understood modalities of receptor function. GOAL: The goal of this review is to provide an up-to-date summary of drug receptor theory. This is followed by a discussion of the drug classes recognized for treating hypertension to which new concepts in receptor theory apply. RESULTS: We raise ideas for mechanisms of potential new antihypertensive drugs and whether they may take advantage of new theories in drug-receptor interaction.

Safety and Efficacy of Renal Denervation in Patients Taking Antihypertensive Medications.

BACKGROUND: Renal denervation (RDN) reduces blood pressure (BP) in patients with uncontrolled hypertension in the absence of antihypertensive medications. OBJECTIVES: This trial assessed the safety and efficacy of RDN in the presence of antihypertensive medications. METHODS: SPYRAL HTN-ON MED is a prospective, randomized, sham-controlled, patient- and assessor-blinded trial enrolling patients from 56 clinical centers worldwide. Patients were prescribed 1 to 3 antihypertensive medications. Patients were randomized to radiofrequency RDN or sham control procedure. The primary efficacy endpoint was the baseline-adjusted change in mean 24-hour ambulatory systolic BP at 6 months between groups using a Bayesian trial design and analysis. RESULTS: The treatment difference in the mean 24-hour ambulatory systolic BP from baseline to 6 months between the RDN group (n = 206; -6.5 ± 10.7 mm Hg) and sham control group (n = 131; -4.5 ± 10.3 mm Hg) was -1.9 mm Hg (95% CI: -4.4 to 0.5 mm Hg; P = 0.12). There was no significant difference between groups in the primary efficacy analysis with a posterior probability of superiority of 0.51 (Bayesian treatment difference: -0.03 mm Hg [95% CI: -2.82 to 2.77 mm Hg]). However, there were changes and increases in medication intensity among sham control patients. RDN was associated with a reduction in office systolic BP compared with sham control at 6 months (adjusted treatment difference: -4.9 mm Hg; P = 0.0015). Night-time BP reductions and win ratio analysis also favored RDN. There was 1 adverse safety event among 253 assessed patients. CONCLUSIONS: There was no significant difference between groups in the primary analysis. However, multiple secondary endpoint analyses favored RDN over sham control. (SPYRAL HTN-ON MED Study [Global Clinical Study of Renal Denervation With the Symplicity Spyral Multi-electrode Renal Denervation System in Patients With Uncontrolled Hypertension in the Absence of Antihypertensive Medications]; NCT02439775).

Fibroblast Growth Factor 23 and Risk of Heart Failure Subtype: The CRIC (Chronic Renal Insufficiency Cohort) Study.

Rationale & Objective: Heart failure (HF) is an important cause of morbidity and mortality among individuals with chronic kidney disease (CKD). A large body of evidence from preclinical and clinical studies implicates excess levels of fibroblast growth factor 23 (FGF23) in HF pathogenesis in CKD. It remains unclear whether the relationship between elevated FGF23 levels and HF risk among individuals with CKD varies by HF subtype. Study Design: Prospective cohort study. Settings & Participants: A total of 3,502 participants were selected in the Chronic Renal Insufficiency Cohort study. Exposure: Baseline plasma FGF23. Outcomes: Incident HF by subtype and total rate of HF hospitalization. HF was categorized as HF with preserved ejection fraction (HFpEF, ejection fraction [EF] ≥ 50%), HF with reduced EF (HFrEF, EF < 50%) and HF with unknown EF (HFuEF). Analytical Approach: Multivariable-adjusted cause-specific Cox proportional hazards models were used to investigate associations between FGF23 and incident hospitalizations for HF by subtype. The Lunn-McNeil method was used to compare hazard ratios across HF subtypes. Poisson regression models were used to evaluate the total rate of HF. Results: During a median follow-up time of 10.8 years, 295 HFpEF, 242 HFrEF, and 156 HFuEF hospitalizations occurred. In multivariable-adjusted cause-specific Cox proportional hazards models, FGF23 was significantly associated with the incidence of HFpEF (HR, 1.41; 95% CI, 1.21-1.64), HFrEF (HR, 1.27; 95% CI, 1.05-1.53), and HFuEF (HR, 1.40; 95% CI, 1.13-1.73) per 1 standard deviation (SD) increase in the natural log of FGF23. The Lunn-McNeil method determined that the risk association was consistent across all subtypes. The rate ratio of total HF events increased with FGF23 quartile. In multivariable-adjusted models, compared with quartile 1, FGF23 quartile 4 had a rate ratio of 1.81 (95% CI, 1.28-2.57) for total HF events. Limitations: Self-report of HF hospitalizations and possible lack of an echocardiogram at time of hospitalization. Conclusions: In this large multicenter prospective cohort study, elevated FGF23 levels were associated with increased risks for all HF subtypes. Plain-Language Summary: Heart failure (HF) is a prominent cause of morbidity and mortality in individuals with chronic kidney disease (CKD). Identifying potential pathways in the development of HF is essential in developing therapies to prevent and treat HF. In a large cohort of individuals with CKD, the Chronic Renal Insufficiency Cohort (N = 3,502), baseline fibroblast growth factor-23 (FGF23), a hormone that regulates phosphorous, was evaluated in relation to the development of incident and recurrent HF with reduced, preserved, and unknown ejection fraction. In this large multicenter prospective cohort study, elevated FGF23 levels were associated with increased risk of all HF subtypes. These findings demonstrate the need for further research into FGF23 as a target in preventing the development of HF in individuals with CKD.

Effect of Intensive Blood Pressure Control on Kidney Outcomes: Long-Term Electronic Health Record-Based Post-Trial Follow-Up of SPRINT.

BACKGROUND: Intensive BP lowering in the Systolic Blood Pressure Intervention Trial (SPRINT) produced acute decreases in kidney function and higher risk for AKI. We evaluated the effect of intensive BP lowering on long-term changes in kidney function using trial and outpatient electronic health record (EHR) creatinine values. METHODS: SPRINT data were linked with EHR data from 49 (of 102) study sites. The primary outcome was the total slope of decline in eGFR for the intervention phase and the post-trial slope of decline during the observation phase using trial and outpatient EHR values. Secondary outcomes included a ≥30% decline in eGFR to <60 ml/min per 1.73 m 2 and a ≥50% decline in eGFR or kidney failure among participants with baseline eGFR ≥60 and <60 ml/min per 1.73 m 2 , respectively. RESULTS: EHR creatinine values were available for a median of 8.3 years for 3041 participants. The total slope of decline in eGFR during the intervention phase was -0.67 ml/min per 1.73 m 2 per year (95% confidence interval [CI], -0.79 to -0.56) in the standard treatment group and -0.96 ml/min per 1.73 m 2 per year (95% CI, -1.08 to -0.85) in the intensive treatment group ( P < 0.001). The slopes were not significantly different during the observation phase: -1.02 ml/min per 1.73 m 2 per year (95% CI, -1.24 to -0.81) in the standard group and -0.85 ml/min per 1.73 m 2 per year (95% CI, -1.07 to -0.64) in the intensive group. Among participants without CKD at baseline, intensive treatment was associated with higher risk of a ≥30% decline in eGFR during the intervention (hazard ratio, 3.27; 95% CI, 2.43 to 4.40), but not during the postintervention observation phase. In those with CKD at baseline, intensive treatment was associated with a higher hazard of eGFR decline only during the intervention phase (hazard ratio, 1.95; 95% CI, 1.03 to 3.70). CONCLUSIONS: Intensive BP lowering was associated with a steeper total slope of decline in eGFR and higher risk for kidney events during the intervention phase of the trial, but not during the postintervention observation phase.

One more step in the renal denervation trek.

Is This REALLY Required?

Effects of a mitochondrial-targeted ubiquinol on vascular function and exercise capacity in chronic kidney disease: a randomized controlled pilot study.

Mitochondria-derived oxidative stress has been implicated in vascular and skeletal muscle abnormalities in chronic kidney disease (CKD). The purpose of this study was to investigate the effects of a mitochondria-targeted ubiquinol (MitoQ) on vascular function and exercise capacity in CKD. In this randomized controlled trial, 18 patients with CKD (means ± SE, age: 62 ± 3 yr and estimated glomerular filtration rate: 45 ± 3 mL/min/1.73 m2) received 4 wk of 20 mg/day MitoQ (MTQ group) or placebo (PLB). Outcomes assessed at baseline and follow-up included macrovascular function measured by flow-mediated dilation, microvascular function assessed by laser-Doppler flowmetry combined with intradermal microdialysis, aortic hemodynamics assessed by oscillometry, and exercise capacity assessed by cardiopulmonary exercise testing. Compared with PLB, MitoQ improved flow-mediated dilation (baseline vs. follow-up: MTQ, 2.4 ± 0.3% vs. 4.0 ± 0.9%, and PLB, 4.2 ± 1.0% vs. 2.5 ± 1.0%, P = 0.04). MitoQ improved microvascular function (change in cutaneous vascular conductance: MTQ 4.50 ± 2.57% vs. PLB -2.22 ± 2.67%, P = 0.053). Central aortic systolic and pulse pressures were unchanged; however, MitoQ prevented increases in augmentation pressures that were observed in the PLB group (P = 0.026). MitoQ did not affect exercise capacity. In conclusion, this study demonstrates the potential for a MitoQ to improve vascular function in CKD. The findings hold promise for future investigations of mitochondria-targeted therapies in CKD.NEW & NOTEWORTHY In this randomized controlled pilot study, we investigated the effects of a mitochondria-targeted ubiquinol (MitoQ) on vascular function and exercise capacity in chronic kidney disease. Our novel findings showed that 4-wk supplementation of MitoQ was well tolerated and improved macrovascular endothelial function, arterial hemodynamics, and microvascular function in patients with stage 3-4 chronic kidney disease. Our mechanistic findings also suggest that MitoQ improved microvascular function in part by reducing the NADPH oxidase contribution to vascular dysfunction.

Prognostic utility of rhythmic components in 24-hour ambulatory blood pressure monitoring for the risk stratification of chronic kidney disease patients with cardiovascular co-morbidity.

Background: Chronic kidney disease (CKD) represents a significant global burden. Hypertension is a modifiable risk factor for rapid progression of CKD. Methods: We extend the risk stratification by introducing the non-parametric determination of rhythmic components in 24-hour profiles of ambulatory blood pressure monitoring (ABPM) in the African American Study for Kidney Disease and Hypertension (AASK) cohort and the Chronic Renal Insufficiency Cohort (CRIC) using Cox proportional hazards models. Results: We find that rhythmic profiling of BP through JTK_Cycle analysis identifies subgroups of CRIC participants at advanced risk of cardiovascular death. CRIC participants with a history of cardiovascular disease (CVD) and absent cyclic components in their BP profile had at any time a 3.4-times higher risk of cardiovascular death than CVD patients with cyclic components present in their BP profile (HR: 3.38, 95% CI: 1.45-7.88, p=0.005). This substantially increased risk was independent of whether ABPM followed a dipping or non-dipping pattern whereby non-dipping or reverse dipping were not significantly associated with cardiovascular death in patients with prior CVD (p>0.1). In the AASK cohort, unadjusted models demonstrate a higher risk in reaching end stage renal disease among participants without rhythmic ABPM components (HR:1.80, 95% CI: 1.10-2.96); however, full adjustment abolished this association. Conclusions: This study proposes rhythmic blood pressure components as a novel biomarker to unmask excess risk among CKD patients with prior cardiovascular disease.

Association of Vitamin K Status with Arterial Calcification and Stiffness in Chronic Kidney Disease: The Chronic Renal Insufficiency Cohort.

Background: Arterial calcification and stiffness are common in people with chronic kidney disease (CKD). Higher vitamin K status has been associated with less arterial calcification and stiffness in CKD in cross-sectional studies. Objectives: To determine the association of vitamin K status with coronary artery calcium (CAC) and arterial stiffness [pulse wave velocity (PWV)] at baseline and over 2-4 follow-up years in adults with mild-to-moderate CKD. Methods: Participants (n = 2722) were drawn from the well-characterized Chronic Renal Insufficiency Cohort. Two vitamin K status biomarkers, plasma phylloquinone and plasma dephospho-uncarboxylated matrix gla protein [(dp)ucMGP], were measured at baseline. CAC and PWV were measured at baseline and over 2-4 y of follow-up. Differences across vitamin K status categories in CAC prevalence, incidence, and progression (defined as ≥100 Agatston units/y increase) and PWV at baseline and over follow-up were evaluated using multivariable-adjusted generalized linear models. Results: CAC prevalence, incidence, and progression did not differ across plasma phylloquinone categories. Moreover, CAC prevalence and incidence did not differ according to plasma (dp)ucMGP concentration. Compared with participants with the highest (dp)ucMGP (≥450 pmol/L), those in the middle category (300-449 pmol/L) had a 49% lower rate of CAC progression (incidence rate ratio: 0.51; 95% CI: 0.33, 0.78). However, CAC progression did not differ between those with the lowest (<300 pmol/L) and those with the highest plasma (dp)ucMGP concentration (incidence rate ratio: 0.82; 95% CI: 0.56, 1.19). Neither vitamin K status biomarker was associated with PWV at baseline or longitudinally. Conclusions: Vitamin K status was not consistently associated with CAC or PWV in adults with mild-to-moderate CKD.

Time in therapeutic range: timely in hypertension therapeutics?

Elevated blood pressure ranks among the most important modifiable risk factors for premature death, and disability from hypertension mediated organ damage in the world. Many studies attest to the value of lifestyle adjustments and pharmacologic therapy in improving outcomes in patients with hypertension. Since blood pressure is a dynamic vitals sign, variability in visit-to-visit measurements is expected. While guidelines recommend a goal blood pressure, increasing attention is centered on how often a patient's blood pressure is found to be not only below the recommended goal value, but also how much of the time the blood pressure is below what is considered a safe lower goal threshold for blood pressure. In this Perspective we review a relatively new technique in addressing adequacy of blood pressure treatment, the time in therapeutic range, and provide examples supporting the clinical relevance of this novel metric.

Socioeconomic characteristics of those with peripheral artery disease in the chronic renal insufficiency cohort.

BACKGROUND: The association between socioeconomic factors and peripheral arterial disease (PAD) has not been as well characterized as other cardiovascular conditions. We sought to define how annual income and education level are associated with PAD in a well-characterized diverse set of adults with chronic kidney disease (CKD). METHODS: The Chronic Renal Insufficiency Cohort Study (CRIC) is a multi-center, prospective cohort study designed to examine risk factors for progression of CKD and cardiovascular disease. Demographic, income, and education-level data, as well as clinical data including ankle-brachial index (ABI) were collected at baseline. Annual income was categorized as < $25,000, $25,000-50,000, $50,000-100,000, or above $100,000; educational level was categorized as some high school, high school graduate, some college, or college graduate. Participants with missing income data or incompressible ABI (>1.4) were excluded from initial analysis. Logistic regression was used to estimate the association of income and/or education level with PAD, defined as an enrollment ABI of <0.90, history of PAD, or history of PAD intervention. RESULTS: A total of 4122 were included, mean age of participants was 59.5 years, 56% were male, and 44% were Black. There were 763 CRIC participants with PAD at study enrollment (18.5%). In the final multivariable logistic regression model, Black race (OR = 1.3, 95% CI 1.1-1.6, p = 0.004) and level of annual household income remained independently associated with PAD at the time of enrollment (income <$25,000 OR = 1.9, 95% CI 1.3-2.8, p < 0.001; income $25,000-50,000 OR = 1.6, 95% CI 1.1-2.3, p = 0.011; income $50,000-100,000 OR = 1.2, 95% CI 0.9-1.8, p = 0.246), relative to a baseline annual income of >$100,000 (overall p-value <0.001). Decreasing level of educational attainment was not independently associated with increased PAD at enrollment, but lower level of educational attainment was associated with increased PAD when income data was not adjusted for (p = 0.001). Interestingly, Black race (OR = 0.7, 95% CI 0.6-0.8, p < 0.001), female gender (OR = 0.8, 95% CI 0.7-0.9, p = 0.007), and income <$25,000 (OR = 0.7, 95% CI 0.5-0.9, p = 0.008) were significantly associated with decreased statin use even after controlling for cardiovascular conditions. CONCLUSIONS: In this prospectively followed CKD cohort, lower annual household income and Black race were significantly associated with increased PAD at study enrollment. In contrast, educational level was not associated with PAD when adjusted for patient income data. Black race, female gender, and low income were independently associated with decreased statin use, populations which could be targets of future public health programs.

Long-term reduction in morning and nighttime blood pressure after renal denervation: 36-month results from SPYRAL HTN-ON MED trial.

Elevated morning and nighttime blood pressures (BP) are associated with increased risk of cardiovascular events such as stroke and myocardial infarction. We compared the long-term changes in morning and nighttime BP in patients with uncontrolled hypertension (office systolic BP between 150 and <180 mmHg/diastolic BP ≥ 90 mmHg; mean ambulatory systolic BP (SBP) between 140 and <170 mmHg; 1-3 prescribed antihypertensive medications). Eighty patients were randomized to RDN or sham control. In patients taking at least 3 antihypertensive medications at 36 months (N = 23 RDN group; N = 23 sham group), the 24 h ambulatory SBP as well as morning (7:00-9:00AM) and nighttime (1:00-6:00AM) ambulatory SBP were significantly lower for the RDN group compared to sham control (24 h SBP: -20.2 vs. -10.2, p = 0.0087; morning SBP: -23.9 vs. -8.0 mmHg, p = 0.029; nighttime SBP: -20.8 vs. -7.2 mmHg, p = 0.0011). At 36 months, 24 h SBP was controlled to <130 mmHg in 40% of RDN patients in the morning compared to 6% for the sham group; P = 0.021 and in 80% of the RDN patients at night compared to 39% in the sham group; P = 0.019. Major adverse events through 36 months were rare in both groups, and there were no renal artery re-interventions or vascular complications. Morning and nighttime SBP were significantly lower in patients prescribed at least 3 antihypertensive medications at 36 months in the SPYRAL HTN-ON MED trial for RDN compared with sham control. The results suggest RDN has significant benefit when the risk of cardiovascular events is highest.

Hypertension management in patients with cardiovascular comorbidities.

Arterial hypertension is a leading cause of death globally. Due to ageing, the rising incidence of obesity, and socioeconomic and environmental changes, its incidence increases worldwide. Hypertension commonly coexists with Type 2 diabetes, obesity, dyslipidaemia, sedentary lifestyle, and smoking leading to risk amplification. Blood pressure lowering by lifestyle modifications and antihypertensive drugs reduce cardiovascular (CV) morbidity and mortality. Guidelines recommend dual- and triple-combination therapies using renin-angiotensin system blockers, calcium channel blockers, and/or a diuretic. Comorbidities often complicate management. New drugs such as angiotensin receptor-neprilysin inhibitors, sodium-glucose cotransporter 2 inhibitors, glucagon-like peptide-1 receptor agonists, and non-steroidal mineralocorticoid receptor antagonists improve CV and renal outcomes. Catheter-based renal denervation could offer an alternative treatment option in comorbid hypertension associated with increased sympathetic nerve activity. This review summarises the latest clinical evidence for managing hypertension with CV comorbidities.

Treatment Adherence in CKD and Support From Health care Providers: A Qualitative Study.

Rationale & Objective: Adherence to recommended medical treatment is critical in chronic kidney disease (CKD) to prevent complications and progression to kidney failure. Overall adherence to treatment is low in CKD, and as few as 40% of patients with kidney failure receive any documented CKD-related care. The purpose of this study was to explore the experiences of patients with CKD and their adherence to CKD treatment plans, and the role their health care providers played in supporting their adherence. Study Design: One-on-one interviews were conducted in 2019-2020 using a semi-structured interview guide. Participants described experiences with adherence to treatment plans and what they did when experiencing difficulty. Setting & Participants: Participants were recruited from the Chronic Renal Insufficiency Cohort (CRIC) study. All CRIC participants were older than 21 years with CKD stages 2-4; this sample consisted of participants from the University of Pennsylvania CRIC site. Analytical Approach: Interviews were recorded, transcribed, and coded using conventional content analysis. Data were organized into themes using NVivo 12. Results: The sample (n = 32) had a mean age of 67 years, 53% were women, 59% were non-White, with a mean estimated glomerular filtration rate of 56.6 mL/min/1.73 m2. From analysis of factors relevant to treatment planning and adherence, following 4 major themes emerged: patient factors (multiple chronic conditions, motivation, outlook), provider factors (attentiveness, availability/accessibility, communication), treatment planning factors (lack of plan, proactive research, provider-focused treatment goals, and shared decision making), and treatment plan responses (disagreeing with treatment, perceived capability deficit, lack of information, and positive feedback). Limitations: The sample was drawn from the CRIC study, which may not be representative of the general population with CKD. Conclusions: These themes align with Behavioral Learning Theory, which includes concepts of internal antecedents (patient factors), external antecedents (provider factors), behavior (treatment planning factors), and consequences (treatment plan responses). In particular, the treatment plan responses point to innovative potential intervention approaches to support treatment adherence in CKD.

Sex differences in microvascular function and arterial hemodynamics in nondialysis chronic kidney disease.

Cardiovascular disease (CVD) is the leading cause of death in chronic kidney disease (CKD). Abnormal arterial hemodynamics contribute to CVD, a relationship that can be mediated by microvascular dysfunction. The purpose of this study was to investigate potential sex differences in arterial hemodynamics and microvascular dysfunction in patients with stages 3 to 4 CKD. Vascular function was assessed in 22 male (mean ± SD; age, 56 ± 13 yr) and 10 female (age, 63 ± 9 yr) patients. Arterial hemodynamics were acquired with combined tonometry and oscillometry. Skin blood flow was used as a model of microvascular function. Participants were instrumented with three microdialysis fibers for the delivery of 1) Ringer's solution; 2) superoxide dismutase mimetic, Tempol; and 3) nicotinamide adenine dinucleotide phosphate (NADPH) oxidase inhibitor, apocynin. Blood flow was measured via laser-Doppler flowmetry during standardized local heating (42°C). Central pulse pressure (mean ± SE; 62 ± 9 vs. 46 ± 3 mmHg; P = 0.01) and augmentation index (36 ± 3 vs. 26 ± 3%; P = 0.03) were higher in females. There was a trend for higher central systolic pressures in females (146 ± 9 vs. 131 ± 3 mmHg; P = 0.06). Females reported higher forward (39 ± 4 vs. 29 ± 2 mmHg; P = 0.004) and reflected (27 ± 3 vs. 19 ± 1 mmHg; P < 0.001) wave amplitudes. Cutaneous vascular function was impaired in females compared with males (77 ± 3 vs. 89 ± 1%, P = 0.001). Microvascular function was improved following the delivery of Tempol and apocynin in females but not in males. Female patients with CKD had poorer central hemodynamics and reduced microvascular function compared with their male counterparts. Oxidative stress may contribute to lower microvascular function observed in females.NEW & NOTEWORTHY There are limited data regarding the physiological mechanisms of potential sex differences in central hemodynamics and vascular function in chronic kidney disease (CKD). We report that older female patients with nondialysis CKD have higher central pulse pressures compared with male patients with CKD. In addition, older females with CKD have lower microvascular function compared with their male counterparts, and oxidative stress contributes to the lower microvascular function in older female patients with CKD.

Long-term outcomes after catheter-based renal artery denervation for resistant hypertension: final follow-up of the randomised SYMPLICITY HTN-3 Trial.

BACKGROUND: The SYMPLICITY HTN-3 (Renal Denervation in Patients With Uncontrolled Hypertension) trial showed the safety but not efficacy of the Symplicity system (Medtronic, Santa Rosa, CA, USA) at 6 months follow-up in patients with treatment-resistant hypertension. This final report presents the 36-month follow-up results. METHODS: SYMPLICITY HTN-3 was a single-blind, multicentre, sham-controlled, randomised clinical trial, done in 88 centres in the USA. Adults aged 18-80 years, with treatment-resistant hypertension on stable, maximally tolerated doses of three or more drugs including a diuretic, who had a seated office systolic blood pressure of 160 mm Hg or more and 24 h ambulatory systolic blood pressure of 135 mm Hg or more were randomly assigned (2:1) to receive renal artery denervation using the single electrode (Flex) catheter or a sham control. The original primary endpoint was the change in office systolic blood pressure from baseline to 6 months for the renal artery denervation group compared with the sham control group. Patients were unmasked after the primary endpoint assessment at 6 months, at which point eligible patients in the sham control group who met the inclusion criteria (office blood pressure ≥160 mm Hg, 24 h ambulatory systolic blood pressure ≥135 mm Hg, and still prescribed three or more antihypertensive medications) could cross over to receive renal artery denervation. Changes in blood pressure up to 36 months were analysed in patients in the original renal artery denervation group and sham control group, including those who underwent renal artery denervation after 6 months (crossover group) and those who did not (non-crossover group). For comparisons between the renal artery denervation and sham control groups, follow-up blood pressure values were imputed for patients in the crossover group using their most recent pre-crossover masked blood pressure value. We report long-term blood pressure changes in renal artery denervation and sham control groups, and investigate blood pressure control in both groups using time in therapeutic blood pressure range analysis. The primary safety endpoint was the incidence of all-cause mortality, end stage renal disease, significant embolic event, renal artery perforation or dissection requiring intervention, vascular complications, hospitalisation for hypertensive crisis unrelated to non-adherence to medications, or new renal artery stenosis of more than 70% within 6 months. The trial is registered with ClinicalTrials.gov, NCT01418261. FINDINGS: From Sep 29, 2011, to May 6, 2013, 1442 patients were screened, of whom 535 (37%; 210 [39%] women and 325 [61%] men; mean age 57·9 years [SD 10·7]) were randomly assigned: 364 (68%) patients received renal artery denervation (mean age 57·9 years [10·4]) and 171 (32%) received the sham control (mean age 56·2 years [11·2]). 36-month follow-up data were available for 219 patients (original renal artery denervation group), 63 patients (crossover group), and 33 patients (non-crossover group). At 36 months, the change in office systolic blood pressure was -26·4 mm Hg (SD 25·9) in the renal artery denervation group and -5·7 mm Hg (24·4) in the sham control group (adjusted treatment difference -22·1 mm Hg [95% CI -27·2 to -17·0]; p≤0·0001). The change in 24 h ambulatory systolic blood pressure at 36 months was -15·6 mm Hg (SD 20·8) in the renal artery denervation group and -0·3 mm Hg (15·1) in the sham control group (adjusted treatment difference -16·5 mm Hg [95% CI -20·5 to -12·5]; p≤0·0001). Without imputation, the renal artery denervation group spent a significantly longer time in therapeutic blood pressure range (ie, better blood pressure control) than patients in the sham control group (18% [SD 25·0] for the renal artery denervation group vs 9% [SD 18·8] for the sham control group; p≤0·0001) despite a similar medication burden, with consistent and significant results with imputation. Rates of adverse events were similar across treatment groups, with no evidence of late-emerging complications from renal artery denervation. The rate of the composite safety endpoint to 48 months, including all-cause death, new-onset end-stage renal disease, significant embolic event resulting in end-organ damage, vascular complication, renal artery re-intervention, and hypertensive emergency was 15% (54 of 352 patients) for the renal artery denervation group, 14% (13 of 96 patients) for the crossover group, and 14% (10 of 69 patients) for the non-crossover group. INTERPRETATION: This final report of the SYMPLICITY HTN-3 trial adds to the totality of evidence supporting the safety of renal artery denervation to 36 months after the procedure. From 12 months to 36 months after the procedure, patients who were originally randomly assigned to receive renal artery denervation had larger reductions in blood pressure and better blood pressure control compared with patients who received sham control. FUNDING: Medtronic.