Predictor Of Pulse Wave Velocity Research Articles

Association Between Critical Limb Ischemia, the Society for Vascular Surgery Wound, Ischemia and Foot Infection (WIfI) Classification System and Arterial Stiffness

Arterial stiffness analysis has been done to classify cardiovascular risk. The aim of this article is to analyze whether the group of patients with chronic limb-threatening ischemia (CLTI) has higher arterial stiffness indices than controls. The secondary objectives are to assess whether patients with advanced stages of Wound, Ischemia, and foot Infection (WIfI) classification have high levels of arterial stiffness, through multiple linear regressions to analyze whether the ankle-brachial index (ABI) and other variables are predictive of arterial stiffness. We conducted a cross-sectional study with 66 patients with CLTI and 66 age- and sex-matched controls using brachial artery oscillometry. Hemodynamic and arterial stiffness measurements, clinical characteristics, laboratory data, and stages of WIfI classification were compared between the groups CLTI and controls. Through multiple linear regression, we identified predictors of pulse wave velocity (PWV) and augmentation index normalized to 75 beats/min (AIx@75). Patients with CLTI had PWV (11.8±1.6m/sec vs. 10.0±1.8m/sec, P<0.01) and AIx@75 (29.2±9.8% vs.18.±10.35%, P<0.01) higher than controls. In the multiple regression model, there was influence of age (β=0.17, P<0.01), antiplatelet therapy (β=-0.15, P=0.04), peripheral systolic pressure (β=0.03, P<0.01), and clustered WIfI stages 3 and 4 (β=0.17, P=0.02) of benefit of revascularization on PWV. Multiple regression analysis identified diabetes (β=7.51, P<0.01) and the degree of ischemia measured by ABI (β=-23.89, P<0.01) as predictors of elevated AIx@75. WIfI stages 3 and 4 of estimate risk of amputationat 1year predicts a high AIx@75 (β=9.77, P<0.001) compared with stages 1 and2. The degree of ischemia in CLTI patients determined by the ABI is associated with elevated arterial stiffness as measured by the AIx@75. Advanced WIfI stages were predictors of elevated PWV and AIx@75.

Determining Factors of Arterial Stiffness in Subjects with Metabolic Syndrome

Metabolic syndrome (MS) is a clustering entity characterized by obesity, hypertension, hyperglycemia, dyslipidemia, and insulin resistance. Early detection of atherosclerosis is important in patients with MS because cardiovascular diseases are the main cause of mortality in these patients. We aimed to investigate the factors influencing arterial stiffness, pulse wave velocity, and the augmentation index, respectively, in 150 subjects with MS (94 women and 56 men; mean age 60.56 ± 9.8 years). Arterial stiffness was measured using the TensioMed™ Arteriograph. We tested the relationship between arterial parameters and insulin resistance measured by the determination of insulinemia (the ELISA method) and the homeostasis model assessment index (HOMA). In multivariate analysis we identified the independent factors that influence arterial stiffness: systolic blood pressure (coefficient of determination 3.586; P < 0.0001), serum triglycerides (coefficient of determination 3.579; P < 0.0001), and age (coefficient of determination 3.510; P = 0.001) are independent predictive factors for pulse wave velocity. The independent predictive factors of the augmentation index were the body mass index (coefficient of determination 0.55; P = 0.009), the presence of diabetes mellitus (coefficient of determination 4.7; P = 0.03), mean arterial pressure (coefficient of determination 0.44; P < 0.0001), gender (coefficient of determination 9.2; P < 0.0001), age (coefficient of determination 0.3; P < 0.0001), and heart rate (coefficient of determination 0.66; P < 0.0001). Insulin resistance (HOMA index) was a predictor of the brachial augmentation index (β coefficient 3.4; P < 0.001) and was not a predictor of pulse wave velocity (β = -0.3; P = 0.6) in our study. Given the known predictive value of pulse wave velocity for cardiovascular events, identifying the factors responsible for the increase in arterial stiffness is extremely important.

Fatty liver index is associated to pulse wave velocity in healthy subjects: Data from the Brisighella Heart Study

BackgroundNon-Alcoholic Fatty Liver Disease (NAFLD) is associated to increased risk of cardiovascular disease. Our aim was to evaluate association of indexes of fatty liver with arterial stiffness (AS). MethodsWe analyzed data of adult volunteers visited during the last Brisighella survey. We evaluated the Pulse Wave Velocity (PWV) and the following non-invasive indexes of liver steatosis: Fatty Liver Index (FLI), Lipid Accumulation Product (LAP), Hepatic Steatosis Index (HSI). We compared patients according to the risk of Non-Alcoholic Steatohepatitis (NASH): low-risk (BMI < 28 and no diabetes), intermediate-risk (BMI ≥ 28 or diabetes), high-risk (BMI ≥ 28 and diabetes). Multiple Linear Regression analysis was assessed for predictors of AS. ResultsWe studied 1731 volunteers. In subjects with low metabolic risk, HSI (RR = 0.138, 95%CI 0.105–0.170, p < 0.001), FLI (RR = 0.024, 95%CI 0.016–0.032, p < 0.001), LAP (RR = 0.014, 95%CI 0.008–0.020, p < 0.001) and Serum Uric Acid (RR = 0.150, 95%CI 0.024–0.275, p = 0.019) were significant predictors of AS. HSI and FLI emerged as predictors of PWV in intermediate risk group (RR = 0.116, 95%CI 0.071–0.160, p < 0.001; RR = 0.010, 95%CI 0.001–0.020, p = 0.041). In volunteers with high risk, FLI and Uric Acid were related to PWV (RR = 0.049, 95%CI 0.011–0.087, p = 0.013; RR = 0.632, 95% CI 0.222–1.041, p = 0.003). ConclusionFatty liver indirect indexes were associated to AS in subjects with different metabolic risk profiles.

Abstract P093: Correlates of Vascular Health in Children and Adolescents With Dyslipidemia

Introduction: Impaired vascular function and structure has been associated with cardiovascular risk factors such as elevated levels of Low Density Lipoprotein cholesterol (LDL-C) and triglycerides, depressed High Density Lipoprotein cholesterol (HDL-C), elevated blood pressure (BP) and body mass index (BMI) in children and young adults. These changes can result in premature coronary artery disease. The degree to which these measures predict vascular damage in children and adolescents is less clear. Hypothesis: We hypothesized that commonly used clinical and laboratory measures will predict vascular health as assessed by measures of carotid artery intima-media thickness (CIMT), pulse wave velocity (PWV), and augmentation index (Aix) in at risk youth. Methods: Children and adolescents with dyslipidemia (n=120, 13.1 ± 1.9 years old, 49% female (59 of 120)) were recruited from a pediatric preventive cardiology clinic. Non-fasting total cholesterol, HDL cholesterol, and triglycerides were obtained prior to the clinic visit. LDL-C and non-HDL-C were calculated with the Martin equation. Remnant particles were calculated as: total cholesterol minus (HDL-C + LDL-C). BP, height, weight, and waist circumference (WC) were measured at the clinic visit. WC was measured 2cm above the iliac crest by a single observer. Tobacco smoke exposure history was obtained using a parent questionnaire. PWV and Aix were measured using a SphygmoCor XCEL combined oscillometric and tonometric device. CIMT was measured via B mode ultrasound on the far wall of the left and right common carotid arteries using a semi-automated edge detection software. Multiple linear regression with backwards selection was used to identify the strongest predictors of CIMT, PWV, and normalized Aix. Results: Age (β=0.26; p=0.002), systolic BP (β=0.16; p=0.04), waist-to-height ratio (β=0.24; p=0.01), hemoglobin A1c (β=0.18; p=0.01) and presence of hypertriglyceridemic waist (defined as triglycerides ≥110mg/dL and WC ≥90 percentile) (β=0.28; p=0.006) were the strongest predictors of PWV (R2=0.353). Diastolic BP (β=0.21; p=0.01), waist-to-height percentile (β=0.22; p=0.01), and remnant particles (β=0.21; p=0.01) were the strongest predictors of normalized Aix (R2=0.175). Age (β=0.19; p=0.03), and systolic BP (β=0.28; p=0.002) were the strongest predictors of CIMT (R2=0.138). Triglycerides, history of tobacco smoke exposure, total cholesterol, LDL-C, HDL-C, and non-HDL-C were not predictive of CIMT, PWV, or normalized Aix. Conclusion: BP consistently predicted was the most common predictor of CIMT, PWV, and Aix in children and adolescents with dyslipidemia. Waist-to-height ratio/percentile was also a reliable predictor in both PWV and Aix. BP and abdominal obesity management should be a focus in this at risk population.

Abstract P204: Growth and Moderators of Pulse Wave Velocity From Childhood to Adulthood

Background: Increased arterial stiffness measured by pulse wave velocity (PWV) has been shown to be an important parameter in the assessment of cardiovascular risk. However little is known about its longitudinal development from childhood to adulthood and its possible sociodemographic, anthropometric, hemodynamic and behavioral moderators. Methods and Results: Individual growth curves of carotid-distal PWV across age were created for 559 African American and European American males and females with a maximum of 5 assessments over a 13-year period (age, 13.7-37.3). African Americans and males had significantly higher PWV than did European Americans and females (Ps&lt;0.01), respectively. A 3-way interaction (P&lt;0.01) between age, gender and ethnicity was observed with African American males displaying a larger rate of increase in PWV with age than the other 3 ethnic and gender groups. The ethnicity and gender effects on PWV persisted when controlling for other moderators. Waist circumstance was the strongest anthropometric predictor but its effect on PWV was only significant in females. Mean arterial pressure was the strongest hemodynamic predictor, marital status of parents was the strongest socioeconomic predictor, and illegal drug use was the strongest behavioral predictor of PWV. The best-fitting full model explained in total 61.6% of the between-subject variance in PWVwith ethnicity, genderand age explaining25%. Conclusion: We observed significant ethnic and gender differences in longitudinal trajectories of PWV in youth and young adults. Apart from these ethnicity and gender effects, individual differences in PWV growth can largely be explained by mean arterial pressure, waist circumstance, marital status and illegal drug use.

Arterial stiffness and its association with clustering of metabolic syndrome risk factors

BackgroundMetabolic syndrome (MetS) is associated with structural and functional vascular abnormalities, which may lead to increased arterial stiffness, more frequent cardiovascular events and higher mortality. However, the role played by clustering of risk factors and the combining pattern of MetS risk factors and their association with the arterial stiffness have yet to be fully understood. Age, hypertension and diabetes mellitus seem to be strongly associated with increased pulse wave velocity (PWV). This study aimed at determining the clustering and combining pattern of MetS risk factors and their association with the arterial stiffness in non-diabetic and non-hypertensive patients.MethodsRecently diagnosed and untreated patients with MetS (n = 64, 49 ± 8 year, 32 ± 4 kg/m2) were selected, according to ATP III criteria and compared to a control group (Control, n = 17, 49 ± 6 year, 27 ± 2 kg/m2). Arterial stiffness was evaluated by PWV in the carotid-femoral segment. Patients were categorized and analyzed according MetS risk factors clustering (3, 4 and 5 factors) and its combinations.ResultsPatients with MetS had increased PWV when compared to Control (7.8 ± 1.1 vs. 7.0 ± 0.5 m/s, p < 0.001). In multivariate analysis, the variables that remained as predictors of PWV were age (β = 0.450, p < 0.001), systolic blood pressure (β = 0.211, p = 0.023) and triglycerides (β = 0.212, p = 0.037). The increased number of risk factors reflected in a progressive increase in PWV. When adjusted to systolic blood pressure, PWV was greater in the group with 5 risk factors when compared to the group with 3 risk factors and Control (8.5 ± 0.4 vs. 7.5 ± 0.2, p = 0.011 and 7.2 ± 0.3 m/s, p = 0.012). Similarly, the 4 risk factors group had higher PWV than the Control (7.9 ± 0.2 vs. 7.2 ± 0.3, p = 0.047).ConclusionsThe number of risk factors seems to increase arterial stiffness. Notably, besides age and increased systolic blood pressure, alterations in the triglycerides worsened the stiffness of large vessels, emphasizing the importance in addressing this risk factor in MetS patients.

Abstract 048: Systolic and Diastolic Ambulatory Blood Pressure Affect Target Organ Damage Differently in Adolescents: The SHIP AHOY Study

Hypertensive target organ damage (TOD) is associated with increased risk for CV events. Ambulatory BP (ABP) measures are more strongly related to TOD than casual BP in adults but data in youth are lacking. Our objective was to determine which ABP parameters associated with TOD in adolescents. We evaluated casual BP (mean of 6 measures by auscultation), ABP (Spacelabs OnTrak), anthropometrics, labs, LVM, pulse wave velocity (PWV), diastolic function (E/E’ ratio), and systolic function (global longitudinal strain, GLS) in 132 adolescents (mean 15.8 + 1.4 yrs, 66% white, 57% male). Day, night and 24H SBP and DBP index (mean/95 th %ile for sex and height) and loads (%readings above the 95 th %ile) were defined according to sex and height-specific pediatric cut-points. General linear models were used to determine independent associations between ABP and TOD. Only systolic ABP means and loads were associated with LVMI and diastolic function, while both systolic and diastolic ABP means and loads were associated with PWV. There was a weak association between systolic and diastolic loads and GLS. In multiple regression analysis (full model: demographics, age, BMI, HR, ABP, metabolic profile, CRP) day SBP index was the strongest predictor of LVMI (β=15.2, R 2 0.4, p=0.006) and E/E’ (β=5.2, R 2 0.23, all p=0.007), while day DBP index was the strongest predictor of PWV (β=3.0, R 2 0.37, p&lt;0.0001). Day DBP load was the sole independent ABP predictor of GLS (β=0.05, R 2 0.25, p=0.02). We conclude that during adolescence, systolic and diastolic ABP parameters are differentially associated with TOD: SBP predicted LVMI, while DBP predicted PWV. ABP parameters may be used to evaluate risk for BP-related TOD.

Clustering and combining pattern of metabolic syndrome risk factors and its association with arterial stiffness

IntroductionMetabolic syndrome (MetS) is associated with structural and functional vascular abnormalities that can lead to increased arterial stiffness, which predicts cardiovascular events and increases mortality. However, little is known regarding the implications of risk factor clustering in the arterial stiffness.ObjectiveIn MetS, determine the clustering and the combining pattern of risk factors and its association with arterial stiffness.MethodsWe selected recently diagnosed patients with MetS (n=47, 51 ± 6 y) according to ATP III criteria. A control group (C, n=17, 50 ± 4 years) was also studied. Arterial stiffness was evaluated by pulse wave velocity (PWV) in carotid‐femoral segment. The patients were categorized and analyzed according MetS risk factors clustering (3, 4 and 5 factors). We performed correlation tests and multiple linear regressions to determine predictor variables with PWV and independent variables of sex, age, body mass index, and MetS risk factors.ResultsPatients with MetS had increased PWV compared to C (8.8 ± 0.7, 9.8 ± 1.4 m/s, p=0.01). In multivariate analysis, the variables that remained as predictor of PWV were age (β=0.35, p= 0.01) and triglycerides (β=0.29, p= 0.03). There was a progressive increase of PWV to increase the number of risk factors. Furthermore, the PWV compared to C group was similar for cluster of 3 risk factors, whereas were higher for cluster of 4 and 5 risk factors (8.7 m/s [7.8 to 10.0], 9.4 m/s [7.7to 11.7], 9.8 m/s [7.3 to 13.4] and 10 m/s [9.3 to 13.4]).ConclusionThe number of risk factors amplifies the arterial stiffness. The presence of alteration in the triglycerides worsening the stiffness of large vessels, emphasizing the importance in addressing this risk factor for MetS patients.Support or Funding InformationThis study was supported by Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP# 2011/17533‐6 ) and, in part, by Fundação Zerbini. Sara Rodrigues was supported by FAPESP# 2013/15323‐0, Edgar Toschi‐Dias was supported by FAPESP# 2013/07651‐7, Felipe X Cepeda was supported by FAPESP# 2015/03274‐0.

Irritable affective temperament is a predictor of pulse wave velocity, whereas hyperthymic affective temperament determines augmentation index in chronic hypertension

Irritable affective temperament is a predictor of pulse wave velocity, whereas hyperthymic affective temperament determines augmentation index in chronic hypertension

The dietary predictors of pulse wave velocity in a cohort with diabetes

The dietary predictors of pulse wave velocity in a cohort with diabetes

Physical activity and arterial stiffness in chronic obstructive pulmonary disease

Arterial stiffness is predictive of cardiovascular events and is elevated in chronic obstructive pulmonary disease (COPD). As physical inactivity and exercise intolerance are associated with elevated arterial stiffness in health, we hypothesized that lower physical activity would be related to increased arterial stiffness in COPD; and that active COPD patients would have reduced arterial stiffness compared to sedentary counterparts. Arterial stiffness was evaluated using pulse wave velocity (PWV) in 33 COPD patients (FEV1=65% predicted) and 10 controls. FEV1%pred, peak oxygen consumption (V˙O2peak), and physical activity data were obtained. The inactive COPD group had higher PWV than controls (9.6 vs. 8.3ms−1, p<0.05); while there was no difference in PWV between the active COPD group and controls. Within the COPD patients, V˙O2peak (r=−0.44, p=0.01) and physical activity (r=−0.38, p=0.03) were the best predictors of PWV. Physical inactivity and exercise intolerance appear to be related to arterial stiffness in COPD, and may contribute to increased cardiovascular disease risk in COPD.

Short-term impact of bariatric surgery on structural and functional parameters of arterial remodeling in morbidly obese patients

Purpose: To assess if severe obesity results in structural and functional remodeling of arteries and to evaluate if weight reduction as a result of bariatric surgery leads to the improvement of these parameters. Material and methods: For the prospective analysis we included 40 patients with severe obesity, assessed before bariatric surgery procedures (OB1) and six months later (OB2). The control group comprised 15 women with normal body mass. Anthropometric measurements, hsCRP, HbA1C, glucose, insulin, MMP-2, MMP-9, adiponectin, E-selectin, CD40L, PAI-1, echocardiogram, intima-media thickness (IMT), pulse wave velocity (PWV), flow-mediated dilatation (FMD%) and nitroglicerine-mediated dilatation (NTG-MD%) were assessed in all subjects and were revaluated in OB2. Results: BMI of patients with severe obesity decreased during the 6-month follow-up post-surgery period (kg/m2): from 47,73 to 35,22. We found hypoadiponectinemia in 90% patients in OB1, in 35% patients in OB2, and in 20% patients in the control group. IMT varied between OB1, OB2: 0,59 vs. 0,52; p<0,0001, and were within the reference value range. In OB1 IMT correlated significantly with body mass (r=0,472), FFM (r=0,427), FM (r=0,368), BMI (r=0,423), 2h insulin concentration (r=0,343), HR (r=0,319), MMP-9 (r=-0,309), CD40L (r=-0,290), HbA1C (r=0,296), NTG-MD% (r=-0,301). Moreover, PWV differed between groups: 8,53 vs. 7,82 m/s; p<0,001. In OB1 PWV correlated with age (r=0,492), HR (r=0,324), and %FM (r=0,328). In OB1 PWV correlated with NTG% (r=-0,332, p=0,036) and hsCRP (r= 0,394, p=0,014). In multivariable analysis, age (p=0,0005) and hsCRP (p=0,0014), were found to be significant predictors of PWV. NTG-MD % differed between OB1 and OB2 (21,47 vs. 28,54%; p<.0001) and were lower in comparison to the control group (31,42±5,95%; p=0,0005). NTG-MD% values correlated with E-selectin values in OB1 (r=-0,380; p=0,015). Conclusions: It seems that weight reduction following bariatric surgery improves both structural and functional indices of large arteries.

Does adiponectin protect against the cardiovascular dysfunction associated with central adiposity in young women with polycystic ovary syndrome?

Purpose: To investigate the relationships between regional adiposity, adiponectin (APN), insulin resistance and cardiovascular function in young women with polycystic ovary syndrome (PCOS). Methods: We studied 180 women aged 16-45y (85 with PCOS, 95 healthy controls) free from overt cardiovascular disease or treated diabetes. Biochemical assays included high molecular weight APN, insulin resistance (HOMA-IR), and glucose and insulin area under the curve (AUC) following oral glucose tolerance test. Regional fat and lean mass were assessed by dual energy x-ray absorptiometry and computed tomography (total, subcutaneous and visceral fat area). Systolic and diastolic function measures included tissue Doppler velocities from echocardiography. Arterial stiffness was assessed using central pulse wave velocity (PWV) from applanation tonometry. Results: After adjusting for age and body mass index (BMI), PCOS subjects had higher glucose AUC, insulin AUC, HOMA-IR, testosterone (p-values all <.005) and, unexpectedly, APN (p=.02). There were no between group differences in cardiovascular measures following adjustment. APN was negatively associated with lean leg mass (r=-.620) and visceral fat (r=-.523) in PCOS subjects (both p<.001) but not in controls, while it was negatively associated with subcutaneous fat in both groups (PCOS r=-.387 [p<.001], controls r=-.244 [p=.022]). In controls, visceral fat (β=.206, p=.036) and age (β=.530, p<.001) were independent predictors of PWV; visceral fat (β=-.274, p=.003), age (β=-.586, p<.001) and insulin AUC (β=-.178, p=.039) were independent predictors of diastolic function. In contrast, there were no independent predictors of PWV in a similar model of PCOS subjects and age was the only independent predictor of diastolic function (β=-.488, p=.001). Conclusion: Despite having a worse metabolic profile, these young women with PCOS had similar cardiovascular function to control subjects of the same age and BMI. APN is a secretory protein which may have a cardio-protective effect. It has an inverse relationship with adiposity, and plasma levels are usually lower in insulin resistant states. APN levels were unexpectedly higher in PCOS subjects when age and BMI were controlled; the association with regional adiposity was different between the groups. Central adiposity was associated with arterial stiffness and diastolic dysfunction in control subjects but not in those with PCOS. Young women with PCOS may be protected against the effects of central obesity on arterial stiffness and diastolic function by a compensatory increase in APN.

Cystatin C is better than albuminuria as a predictor of pulse wave velocity in hypertensive patients

Introduction: Arterial stiffness is important in the evaluation of the cardiovascular risk in both general population and hypertensive patients. In this study, we aimed to investigate the associations of both serum cystatin C levels and albuminuria with arterial stiffness in healthy controls and hypertensive patients.Patients and methods: Seventy-six healthy controls (male/female = 44/32) and 76 hypertensive patients (male/female = 43/33) were enrolled. Arterial stiffness parameters such as augmentation index (AIx) and pulse wave velocity (PWV) were non-invasively measured with the Arteriograph (Tensiomed Ltd., Budapest, Hungary).Results: AIx (31.92 ± 14.31 vs. 27.95 ± 11.03, p = 0.03) and PWV (9.84 ± 1.62 vs. 8.87 ± 2.04, p < 0.001) were significantly higher in hypertensive patients compared to healthy controls. Patients with microalbuminuria had significantly higher AIx (43.47 ± 9.91 vs. 30.37 ± 14.13, p = 0.002) and higher serum cystatin C levels [0.76 (0.67–0.95) vs. 0.68 (0.62–0.78) mg/L, p = 0.03]. In the hypertensive group, AIx was significantly correlated with PWV (r = 0.519, p < 0.001), glomerular filtration rate (cystatin C) (r = –0.438, p = 0.003), mean arterial pressure (MAP) (r = 0.288, p = 0.015) and urinary albumin–creatinine ratio (ACR) (r = 0.386, p = 0.004). PWV was associated with serum cystatin C (r = 0.442, p = 0.003) and MAP (r = 0.377, p = 0.001). In the linear regression analysis (model r = 0.577, p = 0.006) for the prediction of PWV in hypertensive patients, MAP, urinary ACR, age and serum cystatin C levels were included as independent variables. Cystatin C was found to be the significant determinant of PWV in hypertensive patients.Conclusion: Multivariate analysis revealed that serum cystatin C but not albuminuria was significantly associated with PWV in hypertensive patients. Serum cystatin C may be better than albuminuria as a predictor of arterial stiffness in hypertensive patients.

Age- and gender-specific reference values of pulse wave velocity for African adults: preliminary results

Pulse wave velocity (PWV) is an independent predictor of cardiovascular (CV) risk. Higher PWV values have been observed in Africans; however, there are no established age- and gender-adjusted reference values for this population. Therefore, PWV was measured using a validated device (Complior SP) in 544 subjects recruited from an occupational cohort of employees of a public university in Angola. Since high blood pressure (BP) is an important factor influencing PWV, a subsample of 301 normotensive subjects (aged 22-72 years) was selected for this study. A subset of 131 individuals without CV risk factors was considered the healthy group (HG), while the entire group (n = 301) comprised the less healthy group (LHG). Predictors of PWV were evaluated using multiple regression analyses and age- and gender-specific percentile tables and curves were constructed. Age and PWV means were 36 ± 9.7 years and 6.6 ± 1.0 m/s in the HG, respectively, and 39.9 ± 10.2 years and 7.3 ± 1.3 m/s in the LHG. Age and plasma uric acid (UA) were the only significant PWV predictors in the HG, while age, mean BP (MBP), and gender showed significant prediction of PWV in the multiple regression analysis in the LHG. Age- and gender-adjusted reference values of PWV were provided for healthy and less healthy normotensive Africans. Considering the small sample size of our cohort, these preliminary results should be used cautiously until data on robust sample of the general population can be obtained.

Evaluation of structure and stiffness of the common carotid artery in patients with obstructive sleep apnea syndrome by RF QIMT and RF QAS technology

Objective To evaluate the structure and stiffness of the common carotid artery (CCA) in patients with obstructive sleep apnea syndrome (OSAS) by RFQIMT and RFQAS technology and analyze the relationships between the parameters of CCA and cardiovascular risk factors.Methods 113 participants with habitual snoring suspected OSAS were divided into control group,mild,moderate and severe OSAS groups according to apnea hypopnea index(AHI)＜5,5-20,20-40,＞40 event/hour respectively.Carotid parameters included intima-media thickness (IMT),diameter (D),distension (Dis),distensibility coefficient (DC),compliance coefficient (CC),pulse wave velocity (PWV),stiffness index α and β were collected by RFQIMT and RFQAS.Multivariate linear regression analysis was applied to analyze the relationships between CCA parameters and cardiovascular risk factors.Results ①The clinical characteristics:blood pressure had significant difference among the four groups (P ＜0.05).SO2,SO2 min decreased and T90,ODI increased significantly in mild,moderate and severe group (P ＜0.05).②The structure parameters of CCA:IMT,D and plaques had no significant difference among the four groups (P ＞0.05).③The elasticity parameters of CCA:Compared with control group,Dis increased significantly in mild group (P ＜0.05).PWV,α,β increased significantly in moderate group (P ＜ 0.05).Compared with mild group,PWV,α,β increased significantly in moderate group (P ＜0.05).Compared with moderate group,α,β increased significantly in severe group (P ＜0.05).④By multivariate linear regression analysis,age was an independent predictor of IMT,Dis,D,CC,PWV,α,β(P ＜0.05).A blunted nocturnal fall was an independent predictor of D,DC,CC,PWV (P ＜0.05),SBP,DBP and PP of daytime had an important effect on D (P ＜0.05).SO2 was independently correlated with PWV (P ＜0.05).PP was an independent predictor of PWV,α,β (P ＜0.05).Smoking was an independent predictor of plaque (P ＜0.05).Conclusions ①Stiffness is damaged earlier than morphology of CCA in patient with OSAS.②PP,a blunted nocturnal fall and SO2 are correlated with stiffness of CCA significantly.It indicates that abnormal circadian blood pressure rhythm and hypoxia are associated significantly with stiffness of CCA in patient with OSAS. Key words: Ultrasonography; Sleep Apnea, obstructive; Carotid arteries; Stiffness; Intima-media thickness

Does immunosuppressant medication lower blood pressure and arterial stiffness in patients with chronic kidney disease? An observational study

Chronic kidney disease is a proinflammatory state associated with increased arterial stiffness. We hypothesized that chronic kidney disease patients on long-term immunosuppression would have lower arterial stiffness and require treatment with less antihypertensive medication compared with non-immunosuppressed patients. A total of 254 patients (97 on immunosuppression) with chronic kidney disease were recruited from specialist renal clinics. Brachial blood pressure, central aortic pressure and waveform and pulse wave velocity were measured. Age, peripheral blood pressure and pulse wave velocity increased with worsening renal function but were not different between immunosuppressed and non-immunosuppressed patients. Central systolic (P < 0.001) and pulse pressure (P = 0.003) and the number of antihypertensive medications (P < 0.001) increased with worsening renal function and were higher in non-immunosuppressed patients (P = 0.02, P = 0.004 and P < 0.001, respectively). Age, mean arterial pressure, number of antihypertensive medications and a diagnosis of diabetes were found to be independent predictors of pulse wave velocity (R(2) = 0.375; P < 0.001). In a subgroup of 30 patient pairs without diabetes mellitus and cardiovascular disease and with a proven renal diagnosis, carefully matched for age, gender, renal function and systolic pressure, the prescribed antihypertensive medication remained lower in the immunosuppressed patients compared with non-immunosuppressed patients (P = 0.04). Pulse wave velocity was lower in the immunosuppressed group (7.5 ± 1.8 vs. 8.8 ± 1.9 m s(-1); P = 0.02). This study suggests that immunosuppression might be a method of reducing blood pressure and arterial stiffness in patients with chronic kidney disease.

Reference Values of Pulse Wave Velocity in Healthy Children and Teenagers

Carotid-femoral pulse wave velocity is an established method for characterizing aortic stiffness, an individual predictor of cardiovascular mortality in adults. Normal pulse wave velocity values for the pediatric population derived from a large data collection have yet to be available. The aim of this study was to create a reference database and to characterize the factors determining pulse wave velocity in children and teenagers. Carotid-femoral pulse wave velocity was measured by applanation tonometry. Reference tables from pulse wave velocities obtained in 1008 healthy subjects (aged between 6 and 20 years; 495 males) were generated using a maximum-likelihood curve-fitting technique for calculating SD scores in accordance with the skewed distribution of the raw data. Effects of sex, age, height, weight, blood pressure, and heart rate on pulse wave velocity were assessed. Sex-specific reference tables and curves for age and height are presented. Pulse wave velocity correlated positively (P<0.001) with age, height, weight, and blood pressure while correlating negatively with heart rate. After multiple regression analysis, age, height, and blood pressure remained major predictors of pulse wave velocity. This study, involving >1000 children, is the first to provide reference values for pulse wave velocity in children and teenagers, thereby constituting a suitable tool for longitudinal clinical studies assessing subgroups of children who are at long-term risk of cardiovascular disease.

Lifetime Risk Factors and Arterial Pulse Wave Velocity in Adulthood

Limited and partly controversial data are available regarding the relationship of arterial pulse wave velocity and childhood cardiovascular risk factors. We studied how risk factors identified in childhood and adulthood predict pulse wave velocity assessed in adulthood. The study cohort consisted of 1691 white adults aged 30 to 45 years who had risk factor data available since childhood. Pulse wave velocity was assessed noninvasively by whole-body impedance cardiography. The number of conventional childhood and adulthood risk factors (extreme quintiles for low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, systolic blood pressure, body mass index, and smoking) was directly associated with pulse wave velocity in adulthood (P=0.005 and P<0.0001, respectively). In multivariable regression analysis, independent predictors of pulse wave velocity were sex (P<0.0001), age (P<0.0001), childhood systolic blood pressure (P=0.002) and glucose (P=0.02), and adulthood systolic blood pressure (P<0.0001), insulin (P=0.0009), and triglycerides (P=0.003). Reduction in the number of risk factors (P<0.0001) and a favorable change in obesity status (P=0.0002) from childhood to adulthood were associated with lower pulse wave velocity in adulthood. Conventional risk factors in childhood and adulthood predict pulse wave velocity in adulthood. Favorable changes in risk factor and obesity status from childhood to adulthood are associated with lower pulse wave velocity in adulthood. These results support efforts for a reduction of conventional risk factors both in childhood and adulthood in the primary prevention of atherosclerosis.

Abstract 5096: Early versus Late Initiation of Antiretroviral Therapy and Arterial Stiffness in HIV Infection

Background: HIV infection is associated with increased rates of cardiovascular disease. Assessment of arterial stiffness via pulse wave velocity (PWV) is strongly associated with cardiovascular risk, and prior studies have shown that HIV-infected patients have higher stiffness compared to controls. Current guidelines recommend initiation of antiretroviral therapy at a CD4 T cell count of 350 cells/ul. Whether earlier initiation of HIV therapy has any effect on cardiovascular risk as assessed by PWV is unknown. Methods: We conducted a cross-sectional study of 81 HIV-infected men who were antiretroviral-treated with undetectable plasma HIV RNA levels. Subjects underwent noninvasive assessment of PWV using the SphygmoCor System (AtCor Medical, Australia). A generalized linear model was used to determine the relationship between traditional cardiovascular risk factors, HIV-related predictors, and arterial stiffness as measured by PWV. Results: The median age was 47 years (IQR 43–54), 36% had a history of hypertension, and 46% had hypercholesterolemia. The median current CD4 T cell count was 539 cells/ul (IQR 324 –736), and nadir CD4 count was 180 cells/ul (IQR 29 –311). The median PWV was 5.3 m/s (IQR 4.9 – 6.2). In unadjusted analyses, age, diabetes, current CD4 count and nadir CD4 count &lt;350 were predictors of PWV (all p &lt;0.05). After adjusting for both traditional cardiovascular risk factors (age, systolic and diastolic BP, hypertension, diabetes, hypercholesterolemia, smoking) and HIV-related covariates, a nadir CD4 count &lt;350 remained independently associated with a 0.58 m/s increase in PWV (95% CI 0.15–1.01, p&lt;0.008). Other significant determinants of PWV in multivariate analyses included age, systolic and diastolic BP, and diabetes. Of note, neither duration of antiretroviral therapy nor exposure to protease inhibitors was associated with degree of arterial stiffness. Conclusions: Among treated HIV-infected individuals, higher PWV is independently associated with both traditional cardiovascular risk factors including age and diabetes, as well as low nadir CD4 count. Our data support the concept that initiation of antiretroviral therapy before low CD4 counts occur may reduce cardiovascular risk among individuals with HIV infection.