Antonella Castiglia

Unfavourable interaction of microalbuminuria and mildly reduced creatinine clearance on aortic stiffness in essential hypertension

The aim of our study was to assess the independent relationships of urinary albumin excretion rate (AER), of creatinine clearance (CrCl) and of their interaction with aortic stiffness in hypertensive patients without overt renal insufficiency. We studied 222 untreated nondiabetic essential hypertensives. In patients with reliable 24-h urine collections, AER and CrCl were determined. Microalbuminuria (MAU) was defined as an AER of 20 to 200 µg/min. Aortic stiffness was assessed by measurement of carotid-femoral pulse wave velocity (c-f PWV). C-f PWV was higher in subjects with MAU than in those without it (p<0.001, even after adjustment for age, sex and mean arterial pressure) and in subjects with CrCl below 90 ml/min/1.73 m(2) when compared to those with greater values of CrCl (p=0.04 after correction for age, sex and mean arterial pressure). There was a significant interaction of MAU and reduced CrCl regarding c-f PWV (p=0.04). In multiple regression analysis, AER and CrCl remained independently associated with aortic stiffness (β=0.22; p<0.001 and β=-0.13; p=0.02, respectively). In essential hypertensive patients microalbuminuria and mildly reduced CrCl are related independently of each other with increased c-f PWV and exert a synergistic unfavourable effect on aortic stiffness.

Average real variability of 24-h systolic blood pressure is associated with microalbuminuria in patients with primary hypertension

Limited and conflicting data are available about the association between short-term blood pressure (BP) variability and urinary albumin excretion rate (uAER). The objective of our study was to analyze the relationships between microalbuminuria (MAU), defined as an uAER between 20 and 200 μg min−1, and short-term BP variability (BPV), assessed as average real variability (ARV), weighted s.d. of 24-h BP and as s.d. of daytime and night-time BP. The study population consisted of 315 untreated essential hypertensives with normal estimated glomerular filtration rate (>60 ml min−1 per 1.73 m2), who underwent 24-h ambulatory BP monitoring and 24-h uAER determination. MAU was detected in 82 (26%) patients. ARV of 24-h systolic BP (SBP) was significantly higher in patients with MAU (9.8 (8.5–11.1) mm Hg) when compared with those without it (9.1 (8–10.2) mm Hg; P=0.007). This difference held (P=0.026) after adjustment for age, mean levels of BP and other potential confounders by analysis of covariance. A statistically significant correlation was also found between ARV of 24-h SBP and uAER (r=0.17; P=0.003). This association remained significant (β=0.15; P=0.01), also taking into account the effect of 24-h average systolic and diastolic BP, age, gender, diabetes, serum uric acid, triglycerides, estimated glomerular filtration rate in multiple regression analyses. All the other indices of short-term BPV tested were not independently associated with MAU. Our results seem to suggest that in essential hypertension, short-term BPV, only when estimated by ARV of 24-h SBP, is independently associated with MAU.

Relationship between kidney findings and systemic vascular damage in elderly hypertensive patients without overt cardiovascular disease

Few studies have investigated the influence of age on the relationships between systemic vascular damage, kidney dysfunction, and intrarenal hemodynamic changes in patients with hypertension without overt cardiovascular disease. The authors enrolled 126 elderly patients with hypertension (aged ≥65 years) and 350 nonelderly patients with hypertension (aged <65 years). Carotid intima‐media thickness, renal resistive index, and aortic pulse wave velocity were performed in all patients. Elderly patients with hypertension had lower estimated glomerular filtration rates and higher albuminuria, renal resistive index, carotid intima‐media thickness, and aortic pulse wave velocity compared with nonelderly patients with hypertension (P < .001). Carotid intima‐media thickness independently correlated with renal resistive index and estimated glomerular filtration rate in nonelderly patients with hypertension, whereas it was significantly related to renal resistive index only in elderly patients with hypertension. Aortic pulse wave velocity was independently associated with albuminuria in nonelderly patients with hypertension, whereas it did not independently correlate with any indexes of renal damage in elderly patients with hypertension. Age is an important modifier of the relationships between renal function and renal hemodynamics with subclinical vascular involvement in elderly persons without cardiovascular disease.

[OP.7B.08] INFLUENCE OF GENDER ON THE RELATIONSHIPS BETWEEN NEW INDICES OF ADIPOSITY AND LEFT VENTRICULAR MASS AND HYPERTROPHY IN HYPERTENSIVE PATIENTS

Objective: The unfavourable effects of the association of obesity with hypertension on cardiac structure and function have been extensively studied. However, controversy still exists about the influence of gender on the relationship between obesity and left ventricular mass (LVM) and hypertrophy (LVH). Even if body mass index (BMI) and waist circumference (WC) are widely used as anthropometric predictors for cardiovascular diseases (CVD), their validity has been questioned. Recently, Body Shape Index (ABSI) and Body Roundness Index (BRI) were proposed as alternative measures of adiposity that may better reflect health status (1–2). Our study was aimed to assess the ability of ABSI and BRI in identifying LVH and to determine whether they are superior to BMI and WC. Moreover, the influence of gender on the relationships between all these indices of adiposity and LVM was also evaluated. Design and method: We enrolled 724 subjects with EH (mean age 45 ± 12 years, 63 % men) without cardiovascular complications. In all subjects the anthropometric indices (weight, height and waist circumference) and the routine biochemical parameters were determined. BMI, ABSI and BRI were calculated. Furthermore, all patients underwent a 24-h blood pressure monitoring and an echocardiogram. LVM was indexed for body surface area (LVMI) and for height2.7 (LVMH2.7). Results: The univariate correlations of LVMI and LVMH2.7 with the measures of adiposity evaluated are shown in the table 1. ROC curves analysis revealed that in overall population (table 2) and in men BRI has a greater ability to identify LVH defined as LVMH2.7 > 51 g/m2.7. Figure. No caption available. Conclusions: Our results seems to suggest that in men, but not in women, the BRI has a greater sensitivity to detect LVH than ABSI and the traditional measures of adiposity.

[PP.22.07] RELATIONSHIPS OF SYMMETRICAL AND ASYMMETRICAL AMBULATORY ARTERIAL STIFFNESS INDEX (AASI) WITH PRECLINICAL RENAL DAMAGE IN UNTREATED HYPERTENSIVE PATIENTS

Objective: The ambulatory arterial stiffness index (AASI), derived from the 24-h diastolic vs systolic blood pressure (BP) regression line, has been proposed as a surrogate measure of arterial stiffness and has been shown to predict stroke in some studies and meta-analyses. An association between AASI and early signs of renal damage has been described. It has been suggested that Symmetric AASI (symAASI) may provide a better clinical approach to evaluate arterial stiffness than the previously proposed asimmetrical AASI (aAASI) The aim of our study was to evaluate the relationships of aAASI and symAASI with preclinical markers of renal damage in hypertensive patients without severe renal dysfunction. Design and method: A total of 226 subjects (mean age 47 ± 14 years, men 54%) with never treated arterial hypertension were enrolled. Urinary albumin excretion rate (AER) and creatinine clearance (CrCl) were measured by 24-h urine collection, Glomerular filtration rate (eGFR) was estimated using CKD-EPI equation (CKD-EPI eGFR) and CrCl corrected for body surface area (BSA). The ambulatory BP was measured for 24-h by the Spacelab 90207 devices. Results: Statistical univariate analyses disclosed significant correlations of symAASI with Log (AER) (r = 0.16; p = 0.017), with CKD-EPI eGFR (r = −0.30; p < 0.0001) and with CrCl/BSA (see figure), Figure. No caption available. while aAASI showed an inverse relationship only with CKD-EPI eGFR (r = − 0.16; p = 0.017). SymAASI (p = 0.005) and aAASI (p = 0.026) were significantly higher in patients with CKD-EPI eGFR < 90 ml/min71.73 m2 than in those with greater values of eGFR. In two multiple regression models in which aAASI and symAASI were regarded separately as outcome variables only symAASI showed an association with Log (AER) (beta: 0.14; p < 0.05) and with CKD-EPI eGFR (beta: −0.14; p < 0.05), independently of various confounding factors. When in this model CKD-EPI eGFR was replaced by CrCl/BSA this latter maintained its negative association with symAASI (beta = −0.21; p = 0.001). Conclusions: Our results seem to suggest that in patients with untreated arterial hypertension symAASI correlate better with preclinical markers of renal damage than do aAASI.