Abstract 5203: Arterial Stiffness and Urinary Albumin Excretion in Hypertension: The Emerging Role of the Soluble Receptor for Advanced Glycation End Products
Introduction: Current evidence suggests that the soluble receptor for advanced glycation end products (sRAGE) participates in the development of vascular disease, while albuminuria and arterial stiffening are associated with atherosclerosis progression.
Hypothesis: Urinary albumin excretion, expressed as the albumin to creatinine ratio (ACR), may be related to sRAGE and arterial stiffness in essential hypertensives.
Methods: Our population consisted of 80 newly diagnosed untreated non-diabetic patients with stage I to II essential hypertension [48 men, mean age=52 years, office blood pressure (BP)=145/93 mmHg]. According to the ACR values determined as the mean of two non-consecutive morning spot urine samples, patients were divided into microalbuminurics (n=27) (mean ACR=30 –300 mg/g) and normoalbuminurics (n=53) (mean ACR<30 mg/g). Moreover, arterial stiffness was evaluated on the basis of carotid to femoral pulse wave velocity (PWV), by means of a computerized method (Complior SP).
Results: Microalbuminurics compared to normoalbuminurics were older (53±6 vs 49±5 years, p<0.05), had higher 24-h systolic BP (140±13 vs 132±12 mmHg, p=0.001), while did not differ regarding sex and metabolic profile (p=NS). Moreover, microalbuminurics compared to normoalbuminurics exhibited higher levels of PWV (8.9±1.8 vs 7.9±1.5 m/sec, p<0.0001), whereas had lower sRAGE (1011±458 vs 1503±931 pg/ml, p=0.003), independently of confounders. In the total population, ACR was positively related to 24-h systolic BP (r=0.514, p<0.0001) and PWV (r=0.588, p<0.0001), whereas it was negatively correlated with sRAGE (r=−0.275, p=0.018). Regarding sRAGE, it was associated with body mass index (r=−0.241, p=0.003), 24-h pulse pressure (r=−0.372, p=0.001) and PWV (r=−0.403, p<0.0001). Multiple regression analysis revealed that age, 24-h systolic BP, PWV and sRAGE were the independent predictors of ACR (R2=0.49, p<0.0001).
Conclusions: In hypertension, microalbuminuria is accompanied by pronounced arterial stiffening and diffuse vascular dysfunction as reflected by lower sRAGE levels. Moreover, the association of sRAGE with ACR and PWV, underscores the catalytic role of this receptor in the progression of the hypertensive atherosclerotic disease.