Femoral-ankle Pulse Wave Velocity Research Articles

Abstract 4126650: Prognostic Value of Femoral-Ankle Pulse Wave Velocity for Cardiovascular Outcomes in Older Adults: The Atherosclerosis Risk in Communities (ARIC) study

Background: Carotid-femoral pulse wave velocity (cfPWV) is a representative measure of central arterial stiffness and an independent predictor of cardiovascular disease (CVD). Femoral-ankle PWV (faPWV) represents peripheral arterial stiffness, but its association with CVD has not been specifically studied. Aim: To compare faPWV and cfPWV regarding their associations with CVD outcomes. Methods: We analyzed 3,402 ARIC participants without prior heart failure (HF), coronary heart disease (CHD), or stroke at visit 5 (2011-13) (mean age 74.8 [SD 4.9] years, 36.1% male, and 78.0% White). faPWV and cfPWV were measured by Omron VP-1000 Plus. The outcomes of interest were composite and individual outcomes of CVD (HF, CHD, and stroke). We ran unadjusted and multivariable Cox proportional hazards models. Results: During a median follow-up of 9.0 years, there were 607 CVD events. Overall, faPWV showed an inverse association with CVD (Table). P-for-trend reached statistical significance in Models 1 and 2 and was borderline significant in Model 3 (p=0.077). In contrast, as anticipated, cfPWV was positively associated with CVD in all Models, although the association was somewhat attenuated in Model 3 (p-for-trend=0.045 and hazard ratio [HR] for top vs. bottom quartile 1.22 [95%CI 0.95-1.56]). Given their opposite patterns, we explored the ratio of cfPWV and faPWV (“cf/fa ratio”) and found that its association with CVD appeared stronger (p-for-trend=0.004 and HR for top vs. bottom quartile 1.37 [1.08-1.74]) than cfPWV. When each CVD subtype was examined separately, HF showed most consistent associations with our stiffness measures, and only the cf/fa ratio remained significant for HF up to Model 3 (p-for-trend=0.010 and HR for top vs. bottom quartile 1.40 [1.03-1.90]). Conclusions: faPWV was inversely associated with CVD, and cf/fa ratio appeared more strongly associated with CVD compared to cfPWV. Our findings indicate distinct prognostic implications of central vs. peripheral arterial stiffness and suggest cf/fa ratio as a new stiffness measure predicting CVD.

Aortic-Femoral Stiffness Gradient and Cardiovascular Risk in Older Adults.

The aortic-femoral arterial stiffness gradient, calculated as the ratio of lower-limb pulse-wave velocity (PWV) to central (aortic) PWV, is a promising tool for assessing cardiovascular disease (CVD) risk, but whether it predicts incident CVD is unknown. We examined the association of the aortic-femoral arterial stiffness gradient measures carotid-femoral stiffness gradient (femoral-ankle PWV divided by carotid-femoral PWV) and the heart-femoral stiffness gradient (femoral-ankle PWV divided by heart-femoral PWV), as well as PWV, with incident CVD (coronary disease, stroke, and heart failure) and all-cause mortality among 3109 participants of the Atherosclerosis Risk in Communities Study cohort (age, 75±5 years; carotid-femoral PWV, 11.5±3.0 m/s), free of CVD. Cox regression was used to estimate hazard ratios (HR) and 95% CIs. Over a median 7.4-year follow-up, there were 322 cases of incident CVD and 410 deaths. In fully adjusted models, only top quartiles of carotid-femoral stiffness gradient (quartile 4: HR, 1.43 [95% CI, 1.03-1.97]; and quartile 3: HR, 1.49 [95% CI, 1.08-2.05]) and heart-femoral stiffness gradient (quartile 4: HR, 1.77 [95% CI, 1.27-2.48]; and quartile 3: HR, 1.41 [95% CI, 1.00-2.00]) were significantly associated with a greater risk of incident CVD. Only high aortic stiffness in combination with low lower-limb stiffness was significantly associated with incident CVD (HR, 1.46 [95% CI, 1.06-2.02]) compared with the referent low aortic stiffness and high lower-limb stiffness. No PWVs were significantly associated with incident CVD. No exposures were associated with all-cause mortality. The aortic-femoral arterial stiffness gradient may enhance CVD risk assessment in older adults in whom the predictive capacity of traditional risk factors and PWV are attenuated.

Effects of pre-exercise intake of plant- and animal-based foods on arterial function and aerobic exercise capacity in healthy young men: a randomized cross-over trial.

The purpose of this study was to examine the effects of plant- versus animal-based food intake before exercise on arterial function and subsequent aerobic exercise capacity. Eleven healthy adult males (mean age, 22.6±1.8 years) participated in this study. A plant- or animal-based randomized meal type crossover comparison was conducted on separate days with a uniform protein, fat, and carbohydrate balance. Both carotid-femoral pulse wave velocity (cfPWV), femoral-ankle pulse wave velocity (faPWV), and brachial artery flow-mediated dilatation (FMD) were measured as indexes of aortic and peripheral arterial stiffness and vascular endothelial function, respectively, before and at 120min after the meal. After these measurements, maximal oxygen uptake was assessed using a graded power test on an electronically braked cycle ergometer. The results revealed that cfPWV was significantly lower, whereas FMD was significantly higher, at 120min after compared with before the plant-based meal (p=0.01 and 0.02, respectively). By contrast, cfPWV and FMD did not change at 120min after compared with before the animal-based meal. In addition, faPWV did not change at 120min after compared with before the meal for either meal type. Maximal oxygen uptake was higher in the plant- than in the animal-based meal type (p=0.02). These results suggest that pre-exercise plant-based food intake may improve central arterial stiffness and vascular endothelial function, which may have favorable implications for aerobic exercise capacity.

Uninterrupted prolonged sitting and arterial stiffness: moderating effect of prior aerobic exercise in physically active adults.

Prolonged sitting acutely increases arterial stiffness, with interruption strategies only providing limited success in offsetting these rises. Acute aerobic exercise is a potent stimulus to decrease arterial stiffness. However, limited information exists on the effectiveness of acute exercise to maintain arterial stiffness when performed prior to prolonged sitting, particularly within physically active individuals. Using a randomized crossover design, 22 young, active individuals (50% female) performed two conditions 30min of walking at 55-65% of heart rate reserve (EX) and 30min of standing (STAND) followed by 2.5-h of sitting. Brachial-femoral (bfPWV) and femoral-ankle pulse wave velocity (faPWV) were assessed at Baseline, post-exercise and pre-sitting (Pre), and post-sitting (Post) as estimates of central and peripheral arterial stiffness, respectively. For bfPWV, no interaction, condition, or time effects were observed. For faPWV, an interaction was present (p < 0.001); compared to Baseline, there was a 6.1% decrease for EX (- 0.4m/s, p < 0.001) and a 4.6% increase for STAND (0.3m/s, p = 0.016) for STAND such that there was an 11.3% difference between conditions at Pre (0.7m/s, p < 0.001). From Pre to Post, EX then increased by 11.7% (0.9m/s p < 0.001) while STAND remained unchanged, resulting in no difference between conditions (0.1m/s, p = 0.569). While aerobic exercise resulted in a significant decrease in faPWV prior to sitting, the prior exercise bout did not confer a protective effect against the deleterious effects of uninterrupted sitting. Future work should investigate the combined effect of prior exercise and sitting interruption strategies on markers of arterial stiffness.

Assessment of aortic and peripheral arterial stiffness in patients with knee osteoarthritis by ultrasound Doppler derived pulse wave velocity

Information regarding regional arterial stiffness assessment in osteoarthritis (OA) was scarce and sometimes contradictory. We aimed to investigate the aortic, lower limb peripheral arterial stiffness and their associations with knee OA. Patients with primary knee OA and matched non-OA controls were prospectively enrolled from two medical centers in China. The carotid-femoral pulse wave velocity (cfPWV) and femoral-ankle pulse wave velocity (faPWV) were measured using a novel ultrasound technique. A total of 238 participants (including 128 patients with knee OA and 110 controls) were included. In OA patients, cfPWV was significantly higher than that of non-OA controls (9.40 ± 1.92 vs 8.25 ± 1.26 m/s, P < 0.0001). However, faPWV measurements in OA patients (12.10 ± 2.09 m/s) showed no significant difference compared with that of the controls (11.67 ± 2.52 m/s, P = 0.130). Multiple regression analysis revealed that cfPWV was independently associated with knee OA (P < 0.0001) after adjusting for the confounding factors including age, gender, smoking, mean blood pressure, body mass index, heart rate, high-sensitivity C-reactive protein and lipids profiles. In contrast, faPWV did not show independent association with knee OA (P = 0.372) when after adjusting for confounding factors. In addition, Spearman’s correlation analysis showed cfPWV had a significant correlation with Kellgren-Lawrence score (rs = 0.2333, P = 0.008), but no correlation was founded between faPWV with Kellgren-Lawrence score (rs = 0.1624, P = 0.067) in OA patients. This study demonstrated that stiffening of aorta, but not lower limb arteries, was independently associated with knee OA. Our findings may call for further implementation of routine aortic stiffness assessments so as to evaluate cardiovascular risk in patients with OA.

Association of Segment-Specific Pulse Wave Velocity With Vascular Calcification: The ARIC (Atherosclerosis Risk in Communities) Study.

Pulse wave velocity (PWV) is a noninvasive measure of arterial stiffness and predictor of cardiovascular disease. However, the association between PWV and vascular calcification across different vascular beds has not been fully investigated. This study aimed to quantify the association between PWV and multiterritory calcification and to explore whether PWV can identify individuals with vascular calcification beyond traditional risk factors. Among 1351 older adults (mean age, 79.2 years [SD, 4.1]) from the ARIC (Atherosclerosis Risk in Communities) study, we measured segment-specific PWVs: heart-carotid, heart-femoral, carotid-femoral, heart-ankle, brachial-ankle, and femoral-ankle. Dependent variables were high calcium score (≥75th percentile of Agatston score) across different vascular beds: coronary arteries, aortic valve ring, aortic valve, mitral valve, ascending aorta, and descending aorta. Quartiles of carotid-femoral, heart-femoral, heart-ankle, and brachial-ankle PWV were significantly associated with coronary artery calcium (eg, adjusted odds ratio [OR] for the highest versus lowest quartile of carotid-femoral PWV, 1.84 [95% CI, 1.24-2.74]). Overall, PWVs were most strongly associated with descending aorta calcification, with significant results for carotid-femoral, heart-femoral, heart-ankle, and brachial-ankle PWV (eg, adjusted OR for the highest versus lowest quartile of carotid-femoral PWV, 3.99 [95% CI, 2.61-6.17]). In contrast, femoral-ankle PWV was inversely associated with descending aorta calcification. Some PWVs improved the discrimination of coronary artery calcium and descending aorta calcification beyond traditional risk factors. The associations of PWV with vascular calcification varied substantially across segments, with descending aorta calcification most closely linked to PWVs. Our study suggests that some PWVs, especially carotid-femoral PWV, are helpful to identify individuals with coronary artery calcium and descending aorta calcification.

Associations of blood biomarkers with arterial stiffness in patients with diabetes mellitus: A population-based study.

Arterial stiffness contributes to additional cardiovascular risks in diabetic patients by triggering the loss of vascular and myocardial compliance and promoting endothelial dysfunction. Thus, prevention of arterial stiffness is a public health priority, and the identification of potential biomarkers may provide benefits for early prevention. This study investigates the relationships between serum laboratory tests and pulse wave velocity (PWV) tests. We also investigated the associations between PWV and all-cause mortality. We examined a panel of 33 blood biomarkers among diabetic populations in the Atherosclerosis Risk in Communities Study. The carotid-femoral (cfPWV) and femoral-ankle PWV (faPWV) were measured using an automated cardiovascular screening device. The aortic-femoral arterial stiffness gradient (afSG) was calculated as faPWV divided by cfPWV. Biomarker levels were log-transformed and correlated with PWV. Cox proportional hazard models were employed for survival analysis. Among 1079 diabetic patients, biomarkers including high-density lipoprotein cholesterol, glycated hemoglobin, high-sensitivity troponin T, cystatin C, creatinine, and albuminuria were significantly correlated with afSG (R = 0.078, -0.193, -0.155, -0.153, -0.116, and -0.137, respectively) and cfPWV (R = -0.068, 0.175, 0.128, 0.066, 0.202, and 0.062, respectively). Compared with the lowest tertile of afSG, the risk of all-cause mortality was lower in the highest tertile (hazard ratio 0.543; 95% confidence interval 0.328-0.900). Certain biomarkers related to blood glucose monitoring, myocardial injury, and renal function significantly correlated with PWV, suggesting that these putative risk factors are likely to be important atherosclerosis mechanisms in diabetic patients. AfSG may be an independent predictor of mortality among diabetic populations.

Peripheral Arterial Stiffness is Associated with Maximal Oxygen Uptake in Athletes.

Increased central arterial stiffness is associated with decreased maximal oxygen uptake (V̇O2max). Endurance exercise training improves arterial function throughout the whole body, but the relationship between central and peripheral arterial stiffness and V̇O2max is unknown. The present study investigated the relationship between central and peripheral arterial stiffness and V̇O2max in endurance-trained athletes. Twenty-one young male endurance-trained athletes and 12 sedentary controls were included in this study. Resting values for carotid-femoral velocity and femoral-ankle pulse wave velocity were obtained to assess central and peripheral arterial stiffness, respectively. V̇O2max was obtained by incremental cycle ergometer testing. Both carotid-femoral pulse wave velocity (P=0.019) and femoral-ankle pulse wave velocity (P=0.028) were lower in athletes than in controls. V̇O2max was significantly higher in athletes compared to controls (P<0.001). Significant correlations were found between carotid-femoral pulse wave velocity and V̇O2max (r=-0.510, P=0.018) and between femoral-ankle pulse wave velocity and V̇O2max (r=-0.472, P=0.031) in athletes. However, no correlations were evident in controls. These results suggest that higher V̇O2max is associated with lower peripheral arterial stiffness in addition to central arterial stiffness among endurance-trained athletes.

Four weeks of lower-limb static stretching reduces regional arterial stiffness in middle-aged and older women.

[Purpose] This study aimed to clarify whether habitual lower-limb stretching intervention reduces regional arterial stiffness at the stretched site in middle-aged and older women.[Methods] In this study, the effects of 4 weeks of lower-limb static stretching (of the hip extensor and flexor, knee extensor and flexor, and plantar flexor muscles) were investigated on systemic, central, and peripheral arterial stiffness using pulse wave velocity in 14 healthy middle-aged and older women randomly assigned to either a sedentary control group (67.3 ± 5.6 years; n = 7) or a stretching intervention group (63.4 ± 6.4 years; n = 7).[Results] The femoral-ankle pulse wave velocity (an index of peripheral arterial stiffness) significantly decreased in the intervention group (pre, 1222.4 ± 167.5 cm/s; post, 1122.0 ± 141.1 cm/s) but did not change in the control group (pre, 1122.7 ± 107.7 cm/s; post, 1139.9 ± 77.5 cm/s). However, the brachial-ankle pulse wave velocity as an index of systemic arterial stiffness (control: pre, 1655.7 ± 296.8 cm/s, post, 1646.4 ± 232.1 cm/s; intervention: pre, 1637.6 ± 259.9 cm/s, post, 1560.8 ± 254.7 cm/s) and the carotid-femoral pulse wave velocity as an index of central arterial stiffness (control: pre, 1253.6 ± 346.4 cm/s, post, 1223.6 ± 263.4 cm/s; intervention: pre, 1125.4 ± 204.7 cm/s, post, 1024.9 ± 164.5 cm/s) did not change in either group.[Conclusion] These findings suggest that lower-limb stretching interventions may reduce regional arterial stiffness at the stretched site

Acute effects of the different relaxation periods during passive intermittent static stretching on arterial stiffness.

To clarify whether the relaxation period during stretching affects the degree of elevated shear rate and the degree of reduction of arterial stiffness, we examined relaxation duration to build an adequate stretching protocol. In Experiment 1, the changes in cardiac output, the shear rate in the posterior tibial artery, and blood volume in the calf muscle were measured during recovery (0-60 s) from a single bout of one-legged passive calf stretching in 12 healthy young men. In Experiment 2, the effects of different relaxation periods (5-, 10-, 20-, and 60-s) of passive one-legged intermittent calf stretching (30-s × 6 sets) on the femoral-ankle pulse wave velocity (faPWV) as an index of peripheral arterial stiffness were identified in 17 healthy young men. As a result, the stretched leg's shear rate significantly increased from 0 to 10th s after stretching. The muscle blood volume in the stretched leg significantly reduced during stretching, and then significantly increased during the recovery period after stretching; however, cardiac output remained unchanged during stretching and recovery. Additionally, the reduction in faPWV from the pre-stretching value in the stretched leg was significantly larger in the protocol with 10-s and 20-s relaxation periods than that in the non-stretched leg, but this did not differ in the 5-s and 60-s relaxation periods. These findings suggest that the relaxation periods of intermittent static stretching that cause a high transient increase in shear rate (via reperfusion after microvascular compression by the stretched calf muscles) are effective to reduce arterial stiffness.

Associations of lower-limb atherosclerosis and arteriosclerosis with cardiovascular risk factors and disease in older adults: The Atherosclerosis Risk in Communities (ARIC) study

Background & aimsAtherosclerosis and arteriosclerosis contribute to vascular aging and cardiovascular disease (CVD) risk. Both processes can be assessed simply in the lower-limbs and reflect systemic pathology. However, only atherosclerosis is routinely assessed, typically via ankle-brachial index (ABI). Arteriosclerosis can be assessed using femoral-ankle pulse wave velocity (faPWV), but no studies have identified whether ABI and faPWV similarly associate with overt CVD and risk factors, nor whether faPWV confers additional information. The aims of this study were to (i) compare associations of ABI and faPWV with traditional CVD risk factors, including age, sex, systolic blood pressure (SBP), high-density lipoprotein (HDL), total cholesterol (TC), smoking, and diabetes; and (ii) determine the independent and additive associations of ABI and faPWV with a composite measure of prevalent CVD. MethodsWe evaluated ABI and faPWV in 4330 older-aged (75.3 ± 5.0 years) adults using an oscillometric screening device. Associations between ABI and faPWV with CVD risk factors and CVD were determined using mixed-model linear- and logistic-regression. ResultsABI and faPWV were associated with age, HDL, and smoking. ABI was associated with sex, TC, diabetes. faPWV was associated with SBP. Both ABI and faPWV were inversely associated with CVD. Low ABI (≤0.9 vs. >0.9) and low faPWV (≤9.94 vs. >9.94) increased the odds of CVD by 2.41-fold (95% CI:1.85,3.17) and 1.46-fold (95% CI:1.23,1.74), respectively. The inverse association between faPWV and CVD was independent of ABI and CVD risk factors. ConclusionsABI and faPWV, measures of lower-limb atherosclerosis and arteriosclerosis, are independently associated with CVD risk factors and prevalent CVD. Assessment of faPWV may confer additional risk information beyond ABI.

The aortic-femoral arterial stiffness gradient demonstrates good between-day reliability

The aortic-femoral arterial stiffness gradient, defined as the ratio of femoral-ankle pulse wave velocity to carotid-femoral pulse-wave velocity, demonstrates good between-day reliability in young healthy adults.

Effects of blackcurrant extract on arterial functions in older adults: A randomized, double-blind, placebo-controlled, crossover trial

ABSTRACT Purpose Blackcurrant extract mainly contains anthocyanins. Several reports suggest that anthocyanins have beneficial effect for cardiovascular functions. The aim of this study was to examine the effect of 7-day intake of New Zealand blackcurrant (NZBC) extract on arterial functions, e.g. arterial stiffness, and serum lipids. Methods A randomized, double-blind, placebo-controlled, crossover design study with a washout period of 28 days was conducted. Fourteen older adults participated in this study (age 73.3 ± 1.7 years). Participants took either a 7-day course of placebo or two capsules of NZBC extract (each 300 mg capsule contains 35% blackcurrant extract). Participants took one of the two trials first and then took the other after a washout period. Carotid-femoral pulse-wave velocity, an index of central arterial stiffness, and central blood pressure were measured at baseline and again at the end of the 7-day study period. Results Compared to baseline, carotid-femoral pulse-wave velocity (P = .03) and central blood pressure (P = .02) decreased significantly after the 7-day study period with NZBC intake. In addition, carotid-femoral pulse-wave velocity (P = .04) and central blood pressure (P = .001) in the NZBC intake trial decreased significantly more than in the placebo intake trial. No effects were observed on serum lipids. Conclusion These results suggest that short-term NZBC intake reduces central arterial stiffness and central blood pressure in older adults. Therefore, anthocyanin-rich blackcurrants might be beneficial for maintaining or improving cardiovascular health as an alternative to pharmaceutical medications. Abbreviations Aix: augmentation index; BP: blood pressure; cfPWV: carotid–femoral pulse-wave velocity; CVD: cardiovascular diseases; DBP: diastolic blood pressure; faPWV: femoral-ankle pulse-wave velocity; FG: fasting glucose; HDL: high-density lipoprotein cholesterol; LDL: low-density lipoprotein cholesterol; MBP: mean blood pressure; NZBC: New Zealand blackcurrant; PP: pulse pressure; SBP: systolic blood pressure; TG: triglycerides.

Sex differences in lower-limb arterial stiffness following acute aerobic exercise

Summary Objectives This study was to investigate sex differences in central and peripheral arterial stiffness after exercise in young adults. Methods Sixty-one young adults (32 males, 29 females; age 18–35 years) performed an acute bout of aerobic exercise at 70% of heart rate reserve. The carotid-femoral, carotid-radial, and femoral-ankle pulse wave velocity, and carotid and femoral artery diameters, were measured before exercise and 30- and 60-min after exercise using applanation tonometry (Millar Instruments, Houston, TX, USA) and SphygmoCor (AtCor Medical, Sydney, Australia). Results The sex-by-time interactions were not significant for the carotid-femoral and carotid-radial pulse wave velocity, but were significant for the femoral-ankle pulse wave velocity (P = 0.03). There were also significant sex-by-time interactions for the relative diameter changes in the femoral artery (P = 0.043), but not in the carotid artery. The change in femoral-ankle pulse wave velocity from pre-exercise to 60-min post-exercise was significantly positively correlated with leg lean soft tissue mass in males (P = 0.01, R = 0.45), but not in females. Conclusion Our study shows that the effect of acute aerobic exercise on lower-limb arterial stiffness varies between the sexes, with greater reductions in arterial stiffness in young males than in females.

The Reliability of Lower-Limb Pulse-Wave Velocity Assessments Using an Oscillometric Technique

Sedentary behavior appears to target the athero- and arterio-sclerotic susceptible vasculature of the lower extremities. For example, vascular function in the leg is acutely impaired following periods of prolonged sitting. PURPOSE: Studies have relied on techniques which are challenging to perform, therefore impeding further study. Consequently, there is a pressing need to identify precise (reliable), yet simple, techniques for evaluating lower extremity vascular health. Oscillometric assessment of pulse-wave velocity (PWV) in the leg may be one potential solution. The current study aimed to determine the between-day reliability of femoral-ankle PWV (faPWV) in supine and seated positions using the oscillometric-based SphygmoCor XCEL device. METHODS: 15 participants (22.1 y, 80% F; BMI 22.7) were tested on three mornings in a fasted state, separated by a maximum of 7 days. In a balanced, randomized order, faPWV was measured in sitting and supine positions using SphygmoCor XCEL. Carotid-femoral PWV (cfPWV) was also assessed for quality control. RESULTS: The intra-class correlation coefficient (ICC) for supine faPWV (ICC = 0.89) was above the 0.75 criterion, but not for seated (ICC = 0.54). The standard error of measurement (SEM) was 0.42 m/s and 0.95 m/s in the supine and seated positions, respectively. Similarly, reliability measures for cfPWV met the criterion in the supine (ICC = 0.75, SEM = 0.42 m/s) but not seated positions (ICC = 0.66, SEM = 0.48 m/s). CONCLUSIONS: These findings indicate that, in a healthy cohort, faPWV can be determined in supine position with acceptable precision using SphygmoCor XCEL. The next step is to measure precision in populations of varying age and health states. The use of these devices may provide researchers with a simple and precise way of investigating the impact of sedentary behaviors.

Abstract P365: Objectively Measured Snoring is Associated with Carotid Vascular Remodeling in Overweight and Obese Adults

Introduction: Snoring is often used as a surrogate measure for obstructive sleep apnea (OSA), a sleep disorder associated with elevated cardiovascular disease (CVD) risk. Although the literature supports a link between snoring and CVD, it is not clear if this association is independent of OSA. The objective of our study was to explore the association between snoring and subclinical CVD in adults with and without OSA. We hypothesized that snorers would have a greater burden of subclinical CVD, including thicker carotid intima media thickness (CIMT) and higher pulse wave velocity (PWV). Methods: Cross-sectional analyses were conducted using 24-month follow up data from the Slow Adverse Vascular Effects (SAVE) study, a randomized controlled trial evaluating the effects of weight loss, increased physical activity, and reduced dietary sodium intake on vascular health. The original population included 349 men and women aged 20-45 years and BMI 25-40 kg/m 2 . Participants (n=122) with objective measures of sleep-disordered breathing from a home-based sleep assessment (ResMed ApneaLink) were grouped into three categories using the snoring index (SI) and oxygen desaturation index (ODI). SI is defined as the number of vibratory snoring events per hour of recording time . ODI is the number of oxyhemoglobin desaturations of ≥ 4% per hour of recording . The snoring categories were: OSA (ODI≥5; n=41), heavy snoring (ODI&lt;5, above-median SI; n=40), and normal snoring (ODI&lt;5, below-median SI; n=41). Vascular measures such as carotid-femoral PWV (cfPWV), femoral-ankle PWV (faPWV), brachial-ankle PWV (baPWV), CIMT, and carotid inter-adventitial diameter were compared across snoring groups. We used multiple linear regression to assess the association between snoring and subclinical CVD independent of age, sex, BMI, mean arterial pressure, and intervention group. Results: Participants were on average 40.1 ± 5.9 years old (BMI of 31.6 ± 4.4 kg/m 2 ; 76.2% women and 82% white). Across snoring severity categories, most CVD risk factors worsened including age, blood pressure, BMI, lipids, and fasting glucose (ANOVA; all p &lt;.05). Similarly, vascular measures including faPWV, baPWV, CIMT, inter-adventitial diameter and bulb IMT differed across snoring categories with differences occurring mainly between the normal snoring and OSA groups. Differences in carotid inter-adventitial diameter and CIMT were noted between normal and heavy snoring groups (6.52 ± 0.49 vs. 6.83 ± 0.49; 0.58 ± 0.06 vs. 0.63 ± 0.07; mm), respectively. Following covariate adjustment, differences in carotid inter-adventitial diameter and IMT persisted between normal and heavy snoring categories (p &lt;.05). Conclusion: Our findings suggest that, in overweight and obese adults, objectively measured snoring is related to indices of local vascular remodeling and aging, even in those without OSA. Snoring severity may be associated with CVD risk.

Acute effects of different aerobic exercise duration on pulse wave velocity in healthy young men.

The purpose of present study was to determine the acute effects of different aerobic exercise duration on pulse wave velocity (PWV) in healthy young men. One week after measuring peak oxygen uptake to determine the duration of each exercise trial, 11 healthy males (age: 23.4±0.6 years, height: 172.5±2.3 cm, weight: 64.1±2.4 kg) cycled on an ergometer for 15 (15 min-EX), 30 (30 min-EX) and 45 minutes (45 min-EX) at 65% peak oxygen uptake in random order. After supine rest for at least 15 minutes, aortic (carotid-femoral) and leg (femoral-ankle) PWV were measured before and at 30, 60 and 90 minutes after each exercise trial. Compared with before exercise trials, aortic PWV decreased at 30 minutes after 15, 30 and 45 min-EX (P<0.05, P<0.01 and P<0.05, respectively) and persisted for 60 minutes after 30 and 45 min-EX (P<0.05), leg PWV decreased at 30 minutes after 15, 30 and 45 min-EX (P<0.01) and persisted for 60 minutes after 30 and 45 min-EX (P<0.01, respectively). These results suggest that PWV might be further decreased into recovery with prolonged exercise.

Habitual cocoa intake reduces arterial stiffness in postmenopausal women regardless of intake frequency: a randomized parallel-group study.

Arterial stiffness is substantially higher in postmenopausal than in premenopausal women. Daily cocoa intake has been shown to reduce central arterial stiffness in health adults, regardless of age; however, the effect of cocoa-intake frequency on arterial stiffness in postmenopausal women remains unclear. Therefore, the purpose of this study was to investigate the effects of cocoa-intake frequency on arterial stiffness in postmenopausal women. A total of 26 postmenopausal women (mean age ± standard deviation 64±12 years) were randomly assigned to two groups with different cocoa-intake frequencies: one group ingested 17 g of cocoa once daily except on Sundays (every-day group, n=13), and the other ingested 17 g of cocoa twice daily every other day (every-other-day group, n=13). These intake regimens were maintained in both groups for 12 weeks. Carotid–femoral pulse-wave velocity and femoral–ankle pulse-wave velocity were measured in both groups at baseline and again at the end of the 12-week study period. Compared to baseline, both pulse-wave velocities had significantly decreased after the 12-week study period in both groups (P<0.05). However, no significant difference in degree of change was observed between the two groups. Although this study did not include a sedentary control group, these results suggest that regardless of frequency, habitual cocoa intake reduces central and peripheral arterial stiffness in postmenopausal women.

Acute effects of aerobic exercise intensity on arterial stiffness after glucose ingestion in young men.

Arterial stiffness increases after glucose ingestion. Acute low- and moderate-intensity aerobic exercise decreases arterial stiffness. However, the acute effects of 30min of cycling at low- and moderate-intensity [25% (LE trial) and 65% (ME trial) peak oxygen uptake, respectively] on arterial stiffness at 30, 60 and 120min of a postexercise glucose ingestion. Ten healthy young men (age, 22·4±0·5years) performed LE and ME trials on separate days in a randomized controlled crossover fashion. Carotid-femoral (aortic) pulse wave velocity (PWV), femoral-ankle (leg) PWV, carotid augmentation index (AIx) and carotid blood pressure (BP) (applanation tonometry), brachial and ankle BP (oscillometric device), heart rate (HR) (electrocardiography), blood glucose (UV-hexokinase method) and blood insulin (CLEIA method) levels were measured at before (baseline) and at 30, 60 and 120min after the 75-g OGTT. Leg PWV, ankle pulse pressure and BG levels significantly increased from baseline after the 75-g OGTT in the LE trial (P<0·05), but not in the ME trial. Insulin levels and HR significantly increased from baseline after the 75-g OGTT in both trials (P<0·05). Aortic PWV, carotid AIx, brachial BP and carotid BP did not change from baseline after the 75-g OGTT in both trials. The present findings indicate that aerobic exercise at moderate intensity before glucose ingestion suppresses increases leg arterial stiffness after glucose ingestion.

Abstract P054: A Novel Index of Insulin Resistance and Segment-specific Pulse Wave Velocity: The Atherosclerosis Risk in Communities (ARIC) Study

Background: Carotid-femoral pulse wave velocity (cfPWV) is a reference measure of central (elastic) artery stiffness and a risk factor for cardiovascular disease. Femoral-ankle pulse wave velocity (faPWV) is a measure of peripheral (musculo-elastic) arterial stiffness. The ratio of fasting triglycerides (TG) to high-density lipoprotein cholesterol (HDL-C) is a novel and practical marker of insulin resistance (IR), a dysregulation that often precedes diabetes. While diabetes is a known risk factor for arterial stiffening, associations of IR with segment-specific measures of PWV, in those without diabetes, have not been well characterized. Objective: To characterize the cross-sectional association of IR, as indexed by TG/HDL-C, with central and peripheral arterial stiffness by race and gender in older adults without diagnosed diabetes. We hypothesized that TG/HDL-C is positively associated with cfPWV and inversely associated with faPWV. Methods: Our study population included 2477 white and 564 African American adults without diagnosed diabetes examined in 2011-2013 by the ARIC study. cfPWV (cm/s) and faPWV (cm/s) were measured using the Omron VP-1000 Plus system. TG (mg/dL)/HDL-C (mg/dL) was evaluated continuously and categorically. For TG/HDL-C categories, race and gender specific receiver operator characteristic curves were used to determine cut points corresponding to the 75th percentile of fasting insulin, optimized using the Youden index. Elevated TG/HDL-C was dichotomously defined by cut points. Multivariable linear regression was used to model associations, adjusted for age, heart rate, gender, current smoking, and race-center; analyses were stratified by race and gender. Results: The study population was 19% African American and 62% women; mean age was 75 years (SD: 5). TG/HDL-C was positively and monotonically associated with cfPWV, and inversely associated with faPWV. Overall, compared to those without elevated TG/HDL, those with elevated TG/HDL-C had higher cfPWV (β=56 cm/s, 95% CI 35, 78) and, although not significant, lower faPWV (β=-9 cm/s, 95% CI -22, 5). cfPWV was higher in those with elevated TG/HDL-C: 59 cm/s (95% CI 32, 87) in white women, 40 cm/s (95% CI 3, 78) in white men, 50 cm/s (95% CI -20, 120) in African American women, and 101 cm/s (95% CI -10, 212) in African American men. faPWV was lower in white women (β=-23 cm/s, 95% CI -42, -4), but not statistically different in other subgroups. The association of elevated TG/HDL-C with cfPWV and faPWV did not differ by race or gender (p-values &gt;0.1 for all tests for interaction). Conclusions: Higher levels of IR, as indexed by TG/HDL-C, were associated with higher central arterial stiffness and lower peripheral arterial stiffness. These results suggest a role of IR in arterial stiffening in older adults without diabetes.