[Anti-hypertensive treatment and chronotherapy†: when should the pill be taken†?] / Traitement antihypertenseur et chronothérapie†: quand faut-il avaler la pilule†?

When should antihypertensive treatments be administered ? The concept of chronotherapy has been attractive for several years, in connection with the importance of circadian variations in blood pressure. The "too" promising results of the Hygia study argue in its favour. Yet experts caution us about the methodology and results of this study. Vesperal administration of routine anti-hypertensive treatments in all patients is not recommended to date, with a non-negligible risk of excessively lowering the nocturnal blood pressure in some patients (increase of ischemic risk in target organ damage) and on the other hand reducing therapeutic adherence by increasing the number of drug doses. Chronotherapy will therefore only be fully effective if patients are willing to adhere to it.

Quand administrer les traitements antihypertenseurs ? Le concept de chronothérapie séduit depuis plusieurs années, en lien avec l'importance des variations circadiennes de la pression artérielle. Les résultats, «â€…trop ¼ prometteurs de l'étude HYGIA, plaident en sa faveur. Pourtant les experts nous mettent en garde sur la méthodologie et les résultats de cette étude. L'administration vespérale de routine des traitements antihypertenseurs chez tous les patients n'est à ce jour pas recommandée, avec un risque non négligeable, d'une part, de trop baisser la pression artérielle nocturne chez certains patients (augmentation du risque ischémique au niveau des organes cibles) et, d'autre part, de diminuer l'adhérence thérapeutique, en multipliant les prises médicamenteuses. La chronothérapie ne déploiera donc tous ses effets qu'avec l'adhésion thérapeutique des patients.

SFE/SFHTA/AFCE primary aldosteronism consensus: Introduction and handbook.

The French Endocrinology Society (SFE) French Hypertension Society (SFHTA) and Francophone Endocrine Surgery Association (AFCE) have drawn up recommendations for the management of primary aldosteronism (PA), based on an analysis of the literature by 27 experts in 7 work-groups. PA is suspected in case of hypertension associated with one of the following characteristics: severity, resistance, associated hypokalemia, disproportionate target organ lesions, or adrenal incidentaloma with hypertension or hypokalemia. Diagnosis is founded on aldosterone/renin ratio (ARR) measured under standardized conditions. Diagnostic thresholds are expressed according to the measurement units employed. Diagnosis is established for suprathreshold ARR associated with aldosterone concentrations >550pmol/L (200pg/mL) on 2 measurements, and rejected for aldosterone concentration<240pmol/L (90pg/mL) and/or subthreshold ARR. The diagnostic threshold applied is different if certain medication cannot be interrupted. In intermediate situations, dynamic testing is performed. Genetic forms of PA are screened for in young subjects and/or in case of familial history. The patient should be informed of the results expected from medical and surgical treatment of PA before exploration for lateralization is proposed. Lateralization is explored by adrenal vein sampling (AVS), except in patients under 35 years of age with unilateral adenoma on imaging. If PA proves to be lateralized, unilateral adrenalectomy may be performed, with adaptation of medical treatment pre- and postoperatively. If PA is non-lateralized or the patient refuses surgery, spironolactone is administered as first-line treatment, replaced by amiloride, eplerenone or calcium-channel blockers if insufficiently effective or poorly tolerated.

[Chronic kidney disease: screening attitude and practice in the absence of randomized controlled trials]. / Insuffisance rénate chronique: attitudes et pratiques de dépistages en l'absence d'etudes randomisées.

Given the increasing prevalence of chronic kidney disease (CKD), early detection has been proposed. Some organizations recommend CKD screening. Yet, the efficacy of CKD screening is unknown given the absence of randomized controlled trial conducted so far. While CKD screening tests (e.g., glomerular filtration rate) are simple and inexpensive, CKD screening can only be justified if it reduces CKD-related mortality and/or CKD-related morbidity compared to no screening. In addition, CKD screening must provide more benefits than risks to the participants and must be cost-effective. Based on observational studies and cost-effectiveness models, CKD screening has to be proposed to high risk population (patients with hypertension and/or diabetes) but not to the general population.

Noninvasive measurement of absolute renal perfusion by contrast medium-enhanced magnetic resonance imaging.

OBJECTIVE: The aim of this study was to validate the quantification of absolute renal perfusion (RP) determined by dynamic magnetic resonance imaging (MRI) and contrast media using an experimental model in the rabbit and a transit-timed ultrasound flow probe around the left renal artery as comparison. MATERIAL AND METHODS: An MR-compatible ultrasonic time-of-flight flow-probe was placed around the left renal artery in 9 New Zealand white rabbits. Absolute RP in basal state, after mechanical renal artery stenosis, intravenous dopamine, angiotensin II, or colloid infusion was measured using dynamic MRI and intravenous injection of gadoteridol. The results were correlated to the renal artery flow measured inside the magnet with the transit-timed flow-probe. For the signal intensity concentration conversion, we applied different calibrations according to various velocities measured in the aorta by a phase contrast sequence to correct for inflow effect. MRI-derived RP (in mL/min) was calculated by the maximum upslope method, where RP/volume was defined as the ratio of the cortex contrast enhancement slope over the maximum of the arterial input function determined in the aorta. RESULTS: Reproducible arterial and renal transit curve with excellent contrast to noise ratio were obtained. The MRI derived perfusion was systematically underestimated by comparison to the ultrasonic transit-timed flow-probe but was linearly correlated with these measures (r = 0.80, P < 0.001). CONCLUSIONS: Using a flow-sensitive calibration, an accurate arterial input function can be measured from the blood MR signal and used in a realistic model to assess the RP. There was a good correlation between the MR-derived RP and the renal artery blood flow measured by the flow-meter. This experimental study validates absolute RP quantification by MRI and contrast media injection and justifies further clinical studies.