Aldosterone levels, aortic stiffness, and wave reflection in essential hypertensive patients

BACKGROUND The aim of the present study was to evaluate the grade of arterial stiffening, in relation to aldosterone (ALDO) and plasma renin activity (PRA) levels, in essential never-treated hypertensive patients. MATERIALS AND METHODS We studied 1,330 consecutive patients without clinical and/or laboratory findings of primary or secondary aldosteronism. Arterial stiffness indices Aix75 and carotid-femoral pulse wave velocity (PWVc-f) were measured and a 24-hour urine collection for ALDO was carried out to classify patients with low ALDO <12 mcg/24 hours and high ALDO >12 but <24 mcg/24 hours. Patients were divided according to PRA (high PRA > 1ng/ml/hour, low PRA < 1ng/ml/hour) and ALDO levels (high ALDO > 12 but <24 mcg/24 hours, low ALDO < 12 mcg/24 hours) in four groups. Also patients were grouped according to serum ALDO quartiles, 24-hour urine ALDO quartiles, PRA quartiles, and serum ALDO/PRA quartiles. RESULTS Patients were classified in 4 groups: group I (high ALDO and low PRA), group II (high ALDO and high PRA), group III (low ALDO and low PRA), and finally group IV (low ALDO and high PRA). PWVc-f and AoAIx75 were significantly higher in group I followed by group II, III, and IV (P < 0.001). Comparison of arterial stiffness indices according to PRA quartiles and PWVc-f and AoAIx75 showed significantly higher in the 1st quartile compared to 2nd, 3rd, and 4th, respectively (P < 0.001). PWVc-f and AoAIx75 were also compared among the four quartiles of aldosterone-renin ratio and they were significantly higher (P < 0.001) in the 4th quartile followed by the 3rd, 2nd, and 1st, respectively. CONCLUSIONS Arterial stiffness indices are higher among essential hypertensive patients with high normal serum and urine ALDO levels, pointing to a causal relationship between renin-angiotensin-aldosterone system activation and large artery properties. © 2014 American Journal of Hypertension, Ltd. All rights reserved

Urine albumin excretion, within normal range, reflects increasing prevalence of metabolic syndrome in patients with essential hypertension

Microalbuminuria is a prognostic marker of cardiovascular disease and is related to metabolic syndrome (MetS). For this purpose, the authors examined the relationship of low grade albuminuria to MetS, using 4 current definitions and a MetS score. They studied 6650 consecutive, nondiabetic, hypertensive patients with normal microalbumin excretion. MetS was defined by Adult Treatment Panel III, American Heart Association, World Heart Organization, International Diabetes Federation criteria, and MetS Gruppo Italiano per lo Studio della Streptochinasi nell'Infarcto Miocardico (GISSI) score. Urine microalbumin concentration was measured after a 24-hour urine collection by immunonephelometry. By all definitions, hypertensive patients with MetS had higher microalbumin levels. Significantly higher microalbumin levels were observed as the number of metabolic components rose. After adjustment for systolic blood pressure, the strength of this association was reduced to a nonsignificant level. Microalbumin levels, within normal range, are increased in patients with MetS, irrespective of the definition criteria. © 2010 Wiley Periodicals, Inc

Serum phosphate in white-coat hypertensive patients: Focus on dipping status and metabolic syndrome

Recent studies indicate an association between serum phosphate levels and blood pressure in hypertensive patients. A growing body of evidence suggests that white-coat hypertension (WCH) is associated with target organ damage. Furthermore, metabolic syndrome (MS) and a non-dipping pattern are associated with increased cardiovascular risk. The purpose of this study was to explore the nocturnal blood pressure fall in patients with WCH according to their serum phosphate levels and number of MS components fulfilled. The study included 2600 patients with WCH who attended our outpatient clinics. All patients underwent repeated office blood pressure measurements, 24-h ambulatory blood pressure monitoring and full clinical and laboratory evaluation. The diagnosis of MS was made according to the Adult Treatment Panel III criteria. Dipping pattern was defined as follows: dippers had a nocturnal systolic blood pressure (NSBP) fall 10% but 20%; non-dippers had an NSBP fall 10%; extreme dippers had an NSBP fall 20% and reverse dippers had an NSBP increase. There were 314 extreme dippers, 1337 dippers, 734 non-dippers and 116 reverse dippers. Reverse dippers presented with significantly lower levels of serum phosphate, whereas extreme dippers had significantly higher levels (3.39±3.29 vs. 3.58±3.52 mg per 100 ml, P<0.0001). The patients were classified according to the number of MS components and the main observation was the inverse relationship of serum phosphate with MS components (3.53±0.36, 3.50±0.38, 3.49±0.38, 3.44±0.36 and 3.35±0.31 mg per 100 ml, respectively, P<0.003). Patients with WCH and low serum phosphate levels appear to have a higher incidence of a non-dipping NSBP profile and an impaired metabolic profile. This observation may be important for the stratification of the cardiovascular risk in WCH patients. © 2010 The Japanese Society of Hypertension All rights reserved