Abstract 1430: Exaggerated Exercise Blood Pressure Response is Associated with Accelerated Arterial Stiffening and Augmented Asymmetric Dimethylarginine Levels
Introduction: A hypertensive response to exercise (HRE) is associated with high cardiovascular risk, while pronounced arterial stiffness and elevations of asymmetric dimethylarginine (ADMA) levels are related to atherosclerosis progression.
Hypothesis: Increased ADMA and arterial stiffening may be related to HRE in essential hypertensive subjects.
Methods: Our population of 109 newly diagnosed untreated non-diabetics with stage I to II essential hypertension [76 men, mean age=52 years, office blood pressure (BP)=146/94 mmHg] with a negative treadmill exercise test (Bruce protocol) was divided into those with HRE (n=34) (peak exercise systolic BP ≥210mmHg in men and ≥190 mmHg in women) and those without HRE (n=75). In all subjects, arterial stiffness was evaluated on the basis of carotid to femoral pulse wave velocity (PWV) values, by means of a computerized method (Complior SP).
Results: Patients with HRE compared to those without HRE were older (55±9 vs 51±9 years, p<0.05), had greater 24-h systolic BP (141±13 vs 132±12 mmHg, p<0.05), while did not differ regarding metabolic profile and left ventricular mass index (p=NS). Patients with HRE as compared to those without HRE exhibited greater levels of ADMA (0.62±0.05 vs 0.54±0.04 μmol/l, p<0.0001) and PWV (8.9±1.7 vs 7.8±1.2 m/sec, p<0.0001), independently of confounders. In the total population, peak exercise systolic BP was related to 24-h systolic BP (r=0.239, p=0.05), PWV (r=0.289, p=0.002) and ADMA (r=0.260, p=0.007). Regarding ADMA, it was associated with waist to hip ratio (r=0.216, p<0.05), 24-h pulse pressure (r=0.477, p<0.0001) and PWV (r=0.282, p=0.003). Multiple regression analysis revealed that 24-h systolic BP (b=0.225, p=0.004), male sex (b=0.290, p=0.01) and ADMA (b=0.219, p=0.008) were independent predictors of peak exercise systolic BP.
Conclusions: In essential hypertension, a HRE is accompanied by a state of increased arterial stiffening and endothelial dysregulation, as reflected by PWV and ADMA values. The close association of ADMA with exercise BP response and stiffness, further suggests that endothelium-mediated vascular dysfunction is a pathogenic mediator of atherosclerosis progression and contributes to HRE-related risk in hypertension.