Positive association between aldosterone-renin ratio and carotid intima-media thickness in hypertensive children

Authors


Correspondence: Prof. Carlos Fardella, Endocrinology Department, School of Medicine, Pontificia Universidad Catolica de Chile, Lira 85, Floor 5, Santiago 8330074, Chile. Tel.: (56-2) 354 3095; Fax: (56-2) 638-5675; E-mail: cfardella@med.puc.cl

Abstract

Summary

Introduction

From an early age, hypertension can damage blood vessels through multiple mechanisms. The aim of this study was to evaluate the presence of vascular damage and whether it is associated with the mineralo- and glucocorticoid profiles of hypertensive children.

Subjects and methods

We studied 64 hypertensive children. Anthropometric parameters and serum aldosterone (SA), plasma renin activity (PRA), aldosterone/renin ratio (ARR), cortisol (F) and cortisone (E) were measured. The serum F/E ratio was calculated to estimate the activity of the enzyme 11β-HSD2. Vascular damage was determined by carotid intima-media thickness (cIMT) and flow-mediated dilation of the brachial artery (FMD) on ultrasound.

Results (median; Q1–Q3)

Of the patients observed, 39% were females, and the median value for age (years) was 11·2 (9·1–13·3), for BMI (SDS) was 1·36 (0·84–1·80), for body fat mass (%) was 28·3 (17·8–36·0), for SBP index was 1·17 (1·12–1·25) and for the DBP index was 1·27 (1·16–1·36). Measurements revealed an SA level higher than 491 pmol/l in 4/64 patients, a PRA value lower than 0·5 ng/ml/h in 2/64, an ARR higher than 10 in 3/64 and serum F/E ratio higher than 4·3 in 10/64. The median brachial FMD (%) was 8·41 (5·61–10·91), and the median cIMT (mm) was 0·40 (0·37–0·43). The ARR was the only variable that explained changes in cIMT (β = 0·571, R2 0·315, P < 0·0001).

Conclusion

Our results showed a positive association between cIMT and the ARR, suggesting an important role of the renin-aldosterone axis in the regulation of early vascular damage in hypertensive children.

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