Predictor Of Pulse Wave Velocity Research Articles

Abstract 3219: Influence of Adiposity on Arterial Stiffness in Healthy Children

Childhood obesity is increasingly prevalent in the community and is related to adverse cardiovascular outcomes during adulthood. Identification of intermediary markers of preclinical cardiovascular disease may identify high-risk children who would benefit greatest from primary prevention measures. In this study, we evaluated the relationship between adiposity on arterial stiffness in healthy children. In 596 healthy children (mean age 10.1 +/− 0.3 years; 51% boys), we measured body mass index (BMI) and waist circumference (WC). Percentage body fat (%BF) was quantitated by dual-energy x-ray absorptiometry (DEXA). Insulin resistance was assessed by a fasting insulin level and homeostasis model assessment as an index of insulin (HOMA-IR). Carotid-femoral pulse wave velocity (PWV), an index of aortic stiffness, was estimated by applanation tonometry. Compared to girls, boys were older (10.1 vs 10.0 years, p=0.01); and had higher WC (61 vs. 60 cm, p=0.02), lower %BF (24% vs. 29 %, p<0.001), similar BMI (18.0 vs. 18.5, p=0.05) and lower PWV (4.4 vs 4.5 m/sec, p<0.001). In univariate analysis, BMI (ρ=0.26 and ρ=0.31), WC (ρ=0.32 and ρ=0.26) and %BF (ρ=0.23 and ρ=0.30) were correlated positively with PWV in boys and girls, respectively (all p<0.001). After adjustment for age, systolic blood pressure, mean arterial pressure and heart rate, BMI, WC and %BF were significantly associated with PWV (p<0.01) (Table ). HOMA-IR and fasting insulin level were not predictors of PWV (p>0.07 for both). Increased adiposity is related to arterial stiffness in healthy children, independently of blood pressure and heart rate. Further studies are required to evaluate whether public health efforts to promote healthy lifestyles and weight loss in children will reduce arterial stiffness, attenuate the progression of subclinical cardiovascular disease, and prevent the development of subsequent cardiovascular events in the community. Table: Separate Multivariable Models relating Predictor Variable to PWV

Abstract 1316: Preclinical Atherosclerosis in Primary Antiphospholipid Syndrome: The Impact of Oxidative Properties of High Density Lipopoprotein

Background: Antiphospholipid syndrome (APS) is characterised by increased thrombogenicity and/or pregnancy morbidity in the presence of raised levels of antiphospholipid antibodies (aPL). Increased oxidative properties of high density lipoprotein (HDL)(decreased activity of paraoxonase (PON)) is associated with increased risk for atherosclerosis and has been described in APS. The impact of PON on atherosclerotic disease progression in APS is unclear. We therefore examined the effect of PON on intima media thickness (IMT), and pulse wave velocity (PWV) in patients with positive aPL. Methods: We studied 77 women with positive aPL (aPL) aged 46.6±1.2 yrs (mean±SE) and a control group of 77 women aged 47.5±1.2 yrs matched for traditional cardiovascular risk factors. High resolution ultrasound was used to determine carotid IMT. Arterial stiffness was assessed non-invasively by carotid-radial PWV. PON activity was assessed by measuring p-nitrophenol formation and activity expressed as nmoles p-nitrophenol/ml serum/minute. Results: APL patients had significantly increased IMT and PWV compared to controls (0.75±0.02mm vs 0.65±0.01mm, p<0.001 and 9.14±0.18 m/s vs 8.56±0.21m/s, p<0.05 respectively). PON activity was significantly reduced in aPL compared to controls (91.5[64.3, 05.1]mmol/ml/min, median[IQR] vs 103.1[80.4, 111.5] mmol/ml/min, p<0.006). Although PON activity was not associated with vascular measures in controls, an inverse association was noted in aPL patients (r=−0.26 [cIMT] and r=−0.23 [PWV], both p<0.05). In multivariate analysis, accounting for cardiovascular risk factors, PON activity (β=−0.42, p<0.001), age (β=0.33, p<0.001) and systolic blood pressure (β=0.24, p<0.05) were independent determinants of cIMT while PON activity (β=−0.32, p<0.01) and systolic blood pressure (β=0.28, p<0.05) remained the only independent predictors of PWV in aPL positive patients. Conclusions: APS is associated with increased arterial stiffness and carotid intimal thickening. Paraoxonase activity is inversely associated with IMT and PWV in ApL positve patients. These findings indicate that oxidative stress may play an important role in the development of atherosclerosis in patients with primary antiphospholipid syndrome.

Arterial Stiffness Is Related to Systemic Inflammation in Essential Hypertension

The acute phase-reactant high-sensitivity C-reactive protein, a marker of vascular inflammation and an atherosclerotic risk factor, is related to arterial stiffness in healthy subjects and in systemic vasculitis. To explore the relationship between markers of inflammation, interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha), and high-sensitivity C-reactive protein with arterial stiffness, we studied untreated patients (n=78; 56% male; 47+/-1 years of age; mean+/-SEM) with essential hypertension. After overnight fast, augmentation index and pulse wave velocity were assessed noninvasively and related to plasma levels of inflammatory markers measured by ELISA. Pulse wave velocity was significantly related to plasma high-sensitivity C-reactive protein (r=0.31; P<0.001), TNF-alpha, (r=0.30; P<0.001) and IL-6 (r=0.21; P<0.05). There was also a relationship between heart rate-corrected augmentation index to high-sensitivity C-reactive protein (r=0.37; P<0.001), IL-6 (r=0.24; P<0.05), and TNF-alpha (r=0.19, P=0.06). High-sensitivity C-reactive protein was an independent predictor of pulse wave velocity and augmentation index in a multiple stepwise regression model. High-sensitivity C-reactive protein, a marker of systemic inflammation, is independently related to pulse wave velocity, a marker of aortic stiffness, and augmentation index, a manifestation of wave reflection, in essential hypertension.

Elevated C-Reactive Protein Augments Increased Arterial Stiffness in Subjects With the Metabolic Syndrome

We examined whether the presence of an increasing number of metabolic syndrome "disorders" was associated with an increasing pulse wave velocity, which is recognized as a marker of cardiovascular risk, and evaluated whether an elevated plasma C-reactive protein level augments this increasing pulse wave velocity. Using a cross-sectional study design, C-reactive protein, metabolic syndrome-related anthropometric parameters, and pulse wave velocity were measured in 5752 middle-aged Japanese men (44+/-10 years old). In linear regression analyses, all of the metabolic "disorders" and the logarithm of the C-reactive protein significantly correlated with pulse wave velocity. Multiple linear regression analysis demonstrated that triglycerides, HDL cholesterol, mean blood pressure, fasting glucose, and the logarithm of the C-reactive protein were significant independent positive predictors of pulse wave velocity (R-square=0.38). The presence of an increasing number of metabolic "disorders" in the subjects was associated with an increasing pulse wave velocity (no disorders 1228+/-139 cm/s > or =3 disorders 1437+/-250 cm/s; P<0.01). Among subjects with the metabolic syndrome, pulse wave velocity was higher in cases with (1508+/-278 cm/s) than in those without an elevated C-reactive protein (1427+/-243 cm/s; P<0.01). In conclusion, an increase in arterial stiffness may constitute a pathophysiological basis for the increased risk of cardiovascular disease in patients with the metabolic syndrome and that an elevated C-reactive protein level may aggravate this cardiovascular risk.