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The DENERHTN trial (Renal Denervation for Hypertension) confirmed the blood pressure (BP) lowering efficacy of renal denervation added to a standardized stepped-care antihypertensive treatment for resistant hypertension at 6 months. We report here the effect of denervation on 24-hour BP and its variability and look for parameters that predicted the BP response. Patients with resistant hypertension were randomly assigned to denervation plus stepped-care treatment or treatment alone (control). Average and standard deviation of 24-hour, daytime, and nighttime BP and the smoothness index were calculated on recordings performed at randomization and 6 months. Responders were defined as a 6-month 24-hour systolic BP reduction ≥20 mm Hg. Analyses were performed on the per-protocol population. The significantly greater BP reduction in the denervation group was associated with a higher smoothness index ( P =0.02). Variability of 24-hour, daytime, and nighttime BP did not change significantly from baseline to 6 months in both groups. The number of responders was greater in the denervation (20/44, 44.5%) than in the control group (11/53, 20.8%; P =0.01). In the discriminant analysis, baseline average nighttime systolic BP and standard deviation were significant predictors of the systolic BP response in the denervation group only, allowing adequate responder classification of 70% of the patients. Our results show that denervation lowers ambulatory BP homogeneously over 24 hours in patients with resistant hypertension and suggest that nighttime systolic BP and variability are predictors of the BP response to denervation., Clinical Trial Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01570777., (© 2017 American Heart Association, Inc.)

Background: The DENERHTN trial (Renal Denervation for Hypertension) confirmed the blood pressure-lowering efficacy of renal denervation added to a standardized stepped-care antihypertensive treatment for resistant hypertension at 6 months. We report the influence of adherence to antihypertensive treatment on blood pressure control., Methods: One hundred six patients with hypertension resistant to 4 weeks of treatment with indapamide 1.5 mg/d, ramipril 10 mg/d (or irbesartan 300 mg/d), and amlodipine 10 mg/d were randomly assigned to renal denervation plus standardized stepped-care antihypertensive treatment, or the same antihypertensive treatment alone. For standardized stepped-care antihypertensive treatment, spironolactone 25 mg/d, bisoprolol 10 mg/d, prazosin 5 mg/d, and rilmenidine 1 mg/d were sequentially added at monthly visits if home blood pressure was ≥135/85 mm Hg after randomization. We assessed adherence to antihypertensive treatment at 6 months by drug screening in urine/plasma samples from 85 patients., Results: The numbers of fully adherent (20/40 versus 21/45), partially nonadherent (13/40 versus 20/45), or completely nonadherent patients (7/40 versus 4/45) to antihypertensive treatment were not different in the renal denervation and the control groups, respectively (P=0.3605). The difference in the change in daytime ambulatory systolic blood pressure from baseline to 6 months between the 2 groups was -6.7 mm Hg (P=0.0461) in fully adherent and -7.8 mm Hg (P=0.0996) in nonadherent (partially nonadherent plus completely nonadherent) patients. The between-patient variability of daytime ambulatory systolic blood pressure was greater for nonadherent than for fully adherent patients., Conclusions: In the DENERHTN trial, the prevalence of nonadherence to antihypertensive drugs at 6 months was high (≈50%) but not different in the renal denervation and control groups. Regardless of adherence to treatment, renal denervation plus standardized stepped-care antihypertensive treatment resulted in a greater decrease in blood pressure than standardized stepped-care antihypertensive treatment alone., Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01570777., (© 2016 American Heart Association, Inc.)

We report a case of a 76-year-old woman with isolated unilateral Raynaud phenomenon revealing giant-cell arteritis with diffuse arterial lesions and bilateral renal artery stenosis. Doppler ultrasonography showed bilateral stenosis of the subclavian and axillary arteries. Angio-CT PET enlightened diffuse arterial lesions, mainly involving the aorta and the brachial and femoral arteries as well as bilateral renal ostial stenosis with right kidney ischemia. Diagnosis of giant-cell arteritis was made on the temporal artery biopsy. Corticosteroid therapy led to rapid clinical and radiological improvement. Clinical manifestations of giant-cell arteritis may be atypical. Diffuse arterial disease may exist in the absence of cephalic symptoms or significant inflammatory biological features. Ostial renal artery stenosis may induce potentially threatening renal ischemia., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

Kidney transplantation is the favored method to treat end-stage renal disease. Some recipients develop severe diseases requiring admission to an intensive care unit (ICU). Acute kidney injury (AKI) is a common complication among critically ill patients but few data are available among renal transplant recipients. The aim of this monocenter retrospective study was to describe renal function in kidney transplant recipients admitted to an ICU and to evaluate their renal functional recovery after this stay. We identified all renal transplant recipients admitted to our medical ICU from January 1, 2001, to December 31, 2010: namely, 79 stays by 62 patients. We used the glomerular filtration rate criteria of the RIFLE classification to evaluate AKI during the ICU stay. During the ICU stay, 56 patients (70.9%) were classified as "no AKI" according to the RIFLE classification; 11 (13.9%) belonged to class R, 10 (12.7%) to class I, and 2 (2.5%) to class F. Overall, 24% of the patients needed dialysis during the ICU stay. Mortality rate at 3 months after the ICU stay was 25.3%. Among the patients who survived, 40 (68%) recovered to their baseline renal function at 3 months, most of them being classified as no AKI during the ICU stay. We have herein reported the evolution of renal function among kidney graft recipients after an ICU stay., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Background: Glomerular filtration rate (GFR) measurement is a major issue in kidney transplant recipients for clinicians. GFR can be determined by estimating the plasma clearance of iohexol, a nonradiolabeled compound. For practical and convenient application for patients and caregivers, it is important that a minimal number of samples are drawn. The aim of this study was to develop and validate a Bayesian model with fewer samples for reliable prediction of GFR in kidney transplant recipients., Methods: Iohexol plasma concentration-time curves from 95 patients were divided into an index (n = 63) and a validation set (n = 32). Samples (n = 4-6 per patient) were obtained during the elimination phase, that is, between 120 and 270 minutes. Individual reference values of iohexol clearance (CL(iohexol)) were calculated from k (elimination slope) and V (volume of distribution from intercept). Individual CL(iohexol) values were then introduced into the Bröchner-Mortensen equation to obtain the GFR (reference value). A population pharmacokinetic model was developed from the index set and validated using standard methods. For the validation set, we tested various combinations of 1, 2, or 3 sampling time to estimate CL(iohexol). According to the different combinations tested, a maximum a posteriori Bayesian estimation of CL(iohexol) was obtained from population parameters. Individual estimates of GFR were compared with individual reference values through analysis of bias and precision. A capability analysis allowed us to determine the best sampling strategy for Bayesian estimation., Results: A 1-compartment model best described our data. Covariate analysis showed that uremia, serum creatinine, and age were significantly associated with k(e), and weight with V. The strategy, including samples drawn at 120 and 270 minutes, allowed accurate prediction of GFR (mean bias: -3.71%, mean imprecision: 7.77%). With this strategy, about 20% of individual predictions were outside the bounds of acceptance set at ± 10%, and about 6% if the bounds of acceptance were set at ± 15%., Conclusions: This Bayesian approach can help to reduce the number of samples required to calculate GFR using Bröchner-Mortensen formula with good accuracy.

Results from the ONTARGET trial remind us that acute haemodynamically mediated renal dysfunction, triggered by low arterial pressure or volume depletion, can occur in high-risk cardiovascular patients (who usually have some degree of diseased intrarenal vessels) treated with renin-angiotensin system (RAS) blockers (especially in combination). However, nephroprotection could not be properly assessed in the trial, as the population was at low renal risk. Although albuminuria remains a useful marker in many patients, it can neither predict acute renal dysfunction nor replace end-stage renal disease (ESRD) as the endpoint in clinical trials. Recent trials using surrogate endpoints suggest that some RAS blockers (ACE inhibitors, angiotensin receptor blockers, the renin inhibitor aliskiren) may be more nephroprotective than others, but proving this requires comparing them (alone or in combination) in populations with identified renal disease (mainly diabetic nephropathy) and the use of hard endpoints. RAS-blocker dosages are critical: as some patients need much larger doses to decrease proteinuria than do others, the efficacy of a high-dose RAS blocker needs to be assessed in patients with persistent proteinuria. In patients with massive proteinuria despite maximum RAS-blocker dosages, combination RAS blockade should be considered by nephrologists, but will require close monitoring of renal function; also, the treatment needs to be withdrawn (at least temporarily) as soon as volume depletion or excessively low arterial pressure arises. In recent trials, lowering blood pressure towards values recommended by the current guidelines (130/80mmHg) has reduced microvascular (lower levels of urinary albumin excretion) and macrovascular events in diabetic patients.

Background: Smoking may adversely affect the progression of renal diseases. However, it is unknown whether smoking affects renal function in subjects without nephropathy., Methods: In 1998, 28,409 volunteers from the general population were examined at the Institut Régional pour la Santé (IRSA). Renal function was estimated with creatinine clearance using the Cockcroft formula. Dipstick proteinuria was assessed on an overnight urine sample by a trained technician., Results: Adjusted creatinine clearance was higher in current smokers than in former smokers and never smokers (100.6 +/- 13.6 vs. 98.8 +/- 13.9 mL/min/1.73 m2, P < 0.0001, and vs. 98.5 +/- 14.0 mL/min/1. 73 m2, P < 0.0001, respectively). This difference was predominant in men and weak in women, and was associated with the number of cigarettes smoked daily. The slope of the projected age-related decline in the creatinine clearance accelerated with age, but it was similar in current smokers, former smokers, and never smokers. Creatinine clearance was associated with a relative risk of proteinuria [for each mL/min/1.73 m2, the relative risk was 1.007 (95% CI, 1.000 to 1.015), P = 0.056, for 1+ or higher proteinuria; and 1.018 (1.004 to 1.030), P = 0.0078, for 2+ or higher proteinuria]. Current and former smokers had a marked risk of 2 or higher proteinuria [adjusted RR (95% CI), 3.26 (1.66 to 6.80), P = 0. 0009, and 2.69 (1.24 to 5.99), respectively, P = 0.013, vs. never smoking], which was independent of the daily or cumulative cigarette consumption., Conclusions: In the general population, smokers do not exhibit lower creatinine clearance than never smokers. In fact, creatinine clearance is slightly higher in current smokers at least in men, even when normotensive and hypertensive subjects are analyzed separately, but the difference is small, especially in women. This effect seems reversible upon smoking discontinuation. Chronic smoking results in a marked risk of irreversible proteinuria that may occur despite moderate smoking.

-The determinants of the increase in arterial blood pressure associated with the use of estrogen-progestogen oral contraceptives (OC) remain poorly known. The purpose of this study was to assess the renal characteristics and the role of the renin-angiotensin system in women with OC-associated hypertension. Urinary clearances of technetium-labeled diethylene triaminopentaacetic acid (glomerular filtration rate) and 131I-ortho iodohippurate (effective renal plasma flow) were estimated before and after acute administration of captopril in 38 women who became hypertensive while taking OC, 38 non-OC users with essential hypertension matched for age, body mass index, and level of blood pressure, and 38 normotensive women (19 with and 19 without OC). Plasma renin activity was higher in OC hypertensives when compared with those with essential hypertension, but captopril-induced changes in blood pressure and renal hemodynamics and function were similar in both groups. In addition, 24-hours urinary albumin excretion was increased in OC users when compared with nonusers with similar arterial blood pressure. In 13 hypertensive women followed up for 6 months after OC withdrawal, a decrease in plasma renin activity, blood pressure, and glomerular filtration rate but no significant change in urinary albumin excretion and captopril-induced changes in blood pressure and renal hemodynamics were observed. These results indicate that the use of OC is associated with an increased albuminuria and no evidence of a prominent role for the renin-angiotensin system in the maintenance of high blood pressure and renal hemodynamics when compared with non-OC users with essential hypertension.

Background: Cigarette smoking is associated with acute increase in arterial pressure due to systemic vasoconstriction and decreased skin and coronary blood flow. Virtually all cardiovascular effects of cigarette smoking are due to nicotine. However, whether nicotine also affects the renal circulation and function in humans is at present unknown., Methods: In the current study the acute effects of a 4-mg nicotine gum on arterial pressure, heart rate as well as renal haemodynamics and function were assessed in non-smokers and chronic smokers., Results: In non-smokers, mean arterial pressure (+8 +/- 1 mmHg, P<0.001) and heart rate (+13 +/- 3 beats/min, P<0.001) increased whereas effective renal plasma flow (ERPF) and glomerular filtration rate (GFR) decreased by 15 +/- 4% and 14 +/- 4% respectively; in addition, urinary cyclic GMP decreased by 51 +/- 12% in response to nicotine administration. In smokers, mean arterial pressure and heart rate increased similarly; however, in contrast with non-smokers, ERPF and GFR remained unchanged whereas urinary cyclic GMP rose by 87 +/- 43%. Changes in ERPF induced by nicotine were positively correlated with changes in urinary cyclic GMP., Conclusions: These findings indicate that nicotine administration is associated with renal vasoconstriction in healthy non-smokers, possibly through alteration of a cyclic-GMP-dependent vasoactive mechanism. Tolerance to the renal effect of nicotine was observed in chronic smokers, despite the maintenance of the systemic response to nicotine.