Association of small artery elasticity with incident cardiovascular disease in older adults: the multi-ethnic study of atherosclerosis

A pilot study of cardiac guided wave elastography: An ex vivo testing in a rodent model with mechanical testing validation

Many heart diseases can change the elasticity of myocardial tissues, making elastography a potential medical imaging strategy for heart disease diagnosis and cardiovascular risk assessment. Among the existing elastography methods, ultrasound elastography is an appealing choice because of ultrasound's inherent advantages of low cost, high safety, wide availability, and deep penetration. The existing investigations of cardiac ultrasound elastography were implemented based on a bulk model of heart tissue, treating the waves generated in the myocardial tissues as shear waves. In this pilot study, we considered the distinct geometric characteristics of heart tissue, i.e., being a layered structure and its dispersive nature as biological tissue. Based on these considerations, we modeled heart tissues as a layered-dispersive structure and developed a new ultrasound elastography method, ultrasonic guided wave elastography, to characterize the myocardial elasticity. The validity of this layered-dispersive model and the reliability of the developed guided wave elastography were first verified on tissue-mimicking phantoms. Then, the guided wave elastography was applied to an ex vivo imaging of a rat heart tissue specimen in real-time during the biaxial planar mechanical testing. The comparison of the real-time myocardial elasticity obtained from guided wave elastography and mechanical testing demonstrated strong matching, verifying the reliability of the developed cardiac guided wave elastography as a potential method for characterizing myocardial elasticity.

Comparison of arterial stiffness indices measured by pulse wave velocity and pulse wave analysis for predicting cardiovascular and all-cause mortality in a Chinese population

Arterial stiffness measured by pulse wave velocity and pulse wave analysis has been widely studied in different populations in terms of its correlation with cardiovascular events and all-cause mortality. It remains unknown which arterial stiffness index is better for risk stratification in the general population. We included 4129 participants from Gaoyou County, Jiangsu Province, China, with a median follow-up of 11 years. The primary endpoint was cardiovascular mortality, and the secondary endpoint was all-cause mortality. Harrell's C-index, net reclassification improvement (NRI) and integrated discrimination improvement (IDI) based on the Cox proportional hazards regression model were evaluated to assess predictive discrimination and accuracy. The associations between the 4 indices and cardiovascular mortality remained significant after adjusting for the Framingham Risk Score (FRS) and/or associated risk factors. Considering reclassification based on the newly integrated models (FRS model combined with the 4 indices), NRI for cardiovascular mortality showed that haPWV and baPWV had more significant improvement in reclassification compared with C1 and C2 [NRI with 95% CI: haPWV 0.410 (0.293, 0.523); baPWV 0.447 (0.330, 0.553); C1 0.312 (0.182, 0.454); C2 0.328 (0.159, 0.463); all P < 0.05]. This study showed that pulse wave velocity (haPWV and baPWV) provides better discrimination of long-term risk than arterial elasticity indices (C1 and C2) in the general population.

Impaired artery elasticity predicts cardiovascular morbidity and mortality- A longitudinal study in the Vara-Skövde Cohort

It is still debated whether arterial elasticity provides prognostic information for cardiovascular risk beyond blood pressure measurements in a healthy population. To investigate the association between arterial elasticity obtained by radial artery pulse wave analysis and risk for cardiovascular diseases (CVD) in men and women. In 2002-2005, 2362 individuals (men=1186, 50.2%) not taking antihypertensive medication were included. C2 (small artery elasticity) was measured using the HDI/Pulse Wave CR2000. Data on acute myocardial infarction or stroke, fatal or non-fatal, was obtained between 2002-2019. Cox- regression was used to investigate associations between C2 and future CVD, adjusting for confounding factors such as age, sex, systolic blood pressure, heart rate, HOMA-IR (Homeostatic Model Assessment for Insulin Resistance), LDL- cholesterol, CRP (C-Reactive Protein), alcohol consumption, smoking and physical activity. At baseline, the mean age of 46 ± 10.6 years and over the follow-up period, we observed 108 events 70 events in men [event rate: 5.9%], 38 in women [event rate: 3.2%]. In the fully adjusted model, and for each quartile decrease in C2, there was a significant increase in the risk for incident CVD by 36%. (HR = 1.36, 95% CI: 1.01-1.82, p = 0.041). The results were accentuated for all men (HR = 1.74, 95% CI: 1.21-2.50, p = 0.003) and women over the age of 50 years (HR = 1.70, 95% CI: 0.69-4.20). We showed a strong and independent association between C2 and CVD in men. In women after menopause, similar tendencies and effect sizes were observed.

Added value of arterial stiffness index for the 10-year atherosclerotic cardiovascular disease risk determination in a middle-aged population-based study

OBJECTIVE

Atherosclerotic cardiovascular disease (ASCVD) is considered the leading cause of mortality worldwide. Arterial stiffness, measured by arterial stiffness index (ASI), could be a main predictor in target damage of organs. Uncertainty remains regarding the contribution of ASI to estimated ASCVD risk. This study investigates the added value of ASI in ASCVD risk determination using the general UK Biobank middle-aged population.

METHODS

Among 100,598 participants from the UK Biobank population, ASI was assessed and associations between ASCVD risk were stratified by sex and estimated using multiple linear and logistic regressions adjusted for heart rate, physical activity, alcohol status, smocking pack years, BMI categories and CKD.

RESULTS

Males presented higher ASCVD risk than females (8.58% vs. 2.82%, p < 0.001) and higher ASI levels (9.50 m/s vs. 7.00 m/s, p < 0.001). The Youden index was determined at 9.70 m/s in males (p < 0.001) and 10.46 m/s in females (p < 0.001). Among females, participants with ASI > 10.46 m/s showed higher ASCVD risk than others (3.64% vs. 2.56%, p < 0.001), similar results were observed for males (9.92% vs. 7.21%, p < 0.001). In males, ASI showed significant added value information when including overall covariates (AUC = 0.695 vs. AUC = 0.663, p < 0.001). Similar results were observed in females (AUC = 0.693 vs. AUC = 0.687, p = 0.001). In both genders, for the association between ASI and ASCVD risk, nonlinear relationships were observed with higher accuracies than linear models.

CONCLUSION

Further studies should investigate ASCVD risk stratification management depending on ASI measurement.

The association between arterial compliance, as assessed by PTC1 and PTC2 from radial artery waveforms, and age, sex, and race/ethnicity

BACKGROUND

There is limited literature on differences in arterial compliance, as assessed from arterial pressure waveforms, with age, sex, and race/ethnicity. PTC1 and PTC2 are indices of arterial compliance, which are derived from a Windkessel model of the waveform, relatively easy to obtain, and associated with cardiovascular disease.

METHOD

PTC1 and PTC2 were computed from radial artery waveforms from participants of the Multi-Ethnic Study of Atherosclerosis at baseline and again 10 years later. We evaluated the association of PTC1, PTC2, and 10-year change in PTC1 and PTC2 with age, sex, and race/ethnicity.

RESULTS

Among 6245 participants in 2000-2002 (mean ± SD of age was 62 ± 10 years; 52% female; 38% White, 12% Chinese, 27% Black, and 23% Hispanic/Latino), means ± SDs for PTC1 and PTC2 were 394 ± 334 and 94 ± 46 ms. After adjustment for cardiovascular disease risk factors, mean PTC2 was 1.1 ms (95% confidence interval: 1.0, 1.2) lower (arterial stiffness was greater) per year older age, was 22 ms (19, 24) lower for females, and varied by race/ethnicity ( P  < 0.001; e.g., 5 ms lower for Blacks compared with Whites), although the differences were smaller at older ages ( P  < 0.001 for age-sex, P  < 0.001 for age-race/ethnicity interactions). Among 3701 participants with repeat measurements in 2010-2012, arteries had stiffened (mean ± SD 10-year decrease in PTC2: 13 ± 46 ms) consistent with cross-sectional age-trend and tended to stiffen less for females and Blacks consistent with cross-sectional age-interactions.

CONCLUSION

Differences in arterial compliance by age, sex, and race/ethnicity lend support to identify and act on societal factors that may drive health disparities.

Inter-arm systolic blood pressure difference: non-persistence and association with incident cardiovascular disease in the Multi-ethnic Study of Atherosclerosis

We investigated inter-arm systolic blood pressure (sIAD) difference, reproducibility, and incident cardiovascular disease (CVD). We hypothesized that higher sIAD values have low prevalence and nonpersistence over years, but that CVD risk is higher starting from the time of first high absolute sIAD. In Multi-Ethnic Study of Atherosclerosis participants (n = 6725, 53% female, 45-84 years old), Doppler systolic blood pressure (SBP) measurements were made in both arms (10-minute interval) thrice over 9.5 years. Proportional hazards for CVD (coronary heart disease, heart failure, stroke, peripheral arterial disease (PAD)) over 16.4 years were tested according to time-varying absolute inter-arm difference with covariates: (1) age, gender, race, and clinic; (2) model 1 plus height, heart rate, BP, antihypertensives, BMI, smoking status, lipids, lipid lowering medication, and diabetes. High sIAD was not persistent across exams. Maximum absolute sIAD ≥ 15 mmHg was found at least once in 815 persons. Maximum absolute sIAD had a graded relationship with incident stroke or PAD: 6.2% events; model 2 hazard ratio per 10 mmHg 1.34 (95% CI, 1.15-1.56) and this risk was approximately doubled for maximum absolute sIAD ≥ 15 mmHg vs 0-4 mmHg. Total CVD risk (18.4% events) was increased only for maximum absolute sIAD ≥25 mmHg. Associations with incident CVD did not differ for higher SBP in left vs right arm. A higher maximum absolute sIAD at any exam was associated with greater risk for stroke and PAD especially for values ≥ 15 mmHg, and ≥25 mmHg for other CVD. Measuring SBP between arms may help identify individuals at risk for CVD.

Associations of plasma omega-3 and omega-6 pufa levels with arterial elasticity: the multi-ethnic study of atherosclerosis

BACKGROUND

Literature examining the relationship of circulating omega-3 and omega-6 polyunsaturated fatty acids [n-3(ω-3) and n-6 (ω-6) PUFAs] and arterial elasticity in large cohort-based populations are lacking. We investigated the association of circulating ω-3and ω-6 PUFAs with large artery elasticity (LAE) and small artery elasticity (SAE) in participants from the Multi-Ethnic Study of Atherosclerosis (MESA).

METHODS

A total of 6124 participants (mean age 61.9; 52% female; 38% White, 27% Black, 22% Hispanic, and 13% Chinese-American) with plasma phospholipid PUFAs and arterial elasticity measured at baseline were included. LAE and SAE were derived from pulse contour analysis of the radial artery in all subjects in a supine position using tonometry. Linear regression models were used to determine associations for levels of (1) each circulating fatty acid, (2) total ω-3PUFAs, and (3) total ω-6 PUFAs with log-transformed LAE and SAE.

RESULTS

Each standard deviation (SD) increment in circulating levels of total ω-3 PUFAs, eicosapentaenoic acid, and docosahexaenoic acid were associated with a 0.017 ml/mmHg, 0.017 ml/mmHg, and 0.015 ml/mmHg higher LAE respectively (p values all <0.01). No significant trends were observed for ω-3 PUFAs levels with SAE.22 Similarly, no significant trends were observed for ω-6 PUFA levels with either LAE or SAE.

CONCLUSIONS

In a multi-ethnic cohort of individuals free of baseline cardiovascular disease, higher plasma levels of total and individual ω-3 PUFAs were associated with an increased LAE. Further understanding into differential associations of ω-6 PUFAs with LAE and SAE is needed.

Predicting haemodynamic significance of coronary stenosis with radiomics-based pericoronary adipose tissue characteristics

AIM

To investigate the diagnostic performance of the radiomics features of pericoronary adipose tissue (PCAT) in determining haemodynamically significant coronary artery stenosis as evaluated by fractional flow reserve (FFR).

MATERIALS AND METHODS

A total of 92 patients with clinically suspected coronary artery disease who underwent coronary computed tomography (CT) angiography (CCTA), invasive coronary angiography (ICA), and FFR examination within 1 month were included retrospectively, and 121 lesions were randomly assigned to the training and testing set. Based on manual segmentation of PCAT, 1,116 radiomics features were computed. After radiomics robustness assessment and feature selection, radiomics models were established using the different machine-learning algorithms. The area under the receiver operating characteristic (ROC) curve (AUC) and net reclassification index (NRI) were analysed to compare the discrimination and reclassification abilities of radiomics models.

RESULTS

Two radiomics features were selected after exclusions, and both were significantly higher in coronary arteries with FFR ≤0.8 than those with FFR >0.8. ROC analysis showed that the combination of CCTA and decision tree radiomics model achieved significantly higher diagnostic performance (AUC: 0.812) than CCTA alone (AUC: 0.599, p=0.015). Furthermore, the NRI of the combined model was 0.820 and 0.775 in the training and testing sets, respectively, suggesting the radiomics features of PCAT had were effective in classifying the haemodynamic significance of coronary stenosis.

CONCLUSIONS

Adding PCAT radiomics features to CCTA enabled identification of haemodynamically significant coronary artery stenosis.

The relationship between arterial stiffness index and coronary heart disease and its severity

BACKGROUND

Arterial stiffness index (ASI) is closely related to coronary atherosclerosis. This study aims to explore whether ASI can predict coronary heart disease (CHD) and its severity.

METHODS

In this study, a total of 726 patients with suspected CHD were recruited. Based on coronary angiography results, the subjects were assigned into three groups: the control group (without obvious coronary artery disease), single-vessel disease group, and multi-vessel disease group (the number of vessels diseased ≥ 2). At the same time, according to the results of angiography, myocardial enzyme spectrum, electrocardiogram, color Doppler echocardiography and clinical manifestations, these patients were divided into four groups: the control group, stable angina (SA) Group, unstable angina (UA) group, and acute myocardial infarction (AMI) group. We have compared whether there were differences in ASI and related baseline data between groups. Receiver operating curve (ROC) analysis was conducted to determine whether ASI could predict CHD and evaluate the severity.

RESULTS

ASI was positively correlated with the number of diseased branches of coronary artery. The value of ASI was increased as the number of the diseased branches increased. The ASI value in the SA group was significantly higher compared with the control group. Furthermore, the ASI value in the UA and AMI groups was remarkably increased compared with the control and SA groups. The results of ROC analysis indicated that the sensitivity and specificity of ASI was 71.0% and 85.4% in diagnosing CHD, respectively. While ASI was used in predicting the severity of CHD, the sensitivity was 72.1% and specificity 57.9%.

CONCLUSION

ASI is of great value in the diagnosis of coronary heart disease and the prediction of its severity.

The association between indices of blood pressure waveforms (PTC1 and PTC2) and incident heart failure

OBJECTIVES

The radial artery pulse waveform is a continuous measure of pressure throughout the cardiac cycle, and thus can provide more information than just systolic and diastolic blood pressures. New indices based on a Windkessel model of the waveform, PTC1 and PTC2, are related to arterial compliance and add information for prediction of incident cardiovascular disease (coronary heart disease, stroke, myocardial infarction) but their association with heart failure is unknown.

METHODS

Among 6229 adults (mean age 62 years) from four race/ethnic groups who were initially free of clinical cardiovascular disease and heart failure in 2000-2002, we evaluated the associations of baseline PTC1 and PTC2 with incident heart failure.

RESULTS

Mean ± standard deviation PTC1 and PTC2 were 394 ± 334 and 94 ± 46 ms, respectively. During a median of 15.7 years follow-up, there were 357 heart failure events (148 with reduced, 150 with preserved, and 59 with unknown ejection fraction). After adjustment for traditional risk factors, the hazard ratio for heart failure per 1 standard deviation higher PTC2 was 0.73 (95% confidence interval: 0.63--0.85). Higher PTC2 was also significantly associated with lower risk of heart failure with reduced ejection fraction (hazard ratio = 0.67; 95% confidence interval: 0.56--0.80). There was no evidence of a significant association between PTC2 and heart failure with preserved ejection fraction or between PTC1 and heart failure.

CONCLUSION

The PTC2 measure of the radial artery pulse waveform may represent a novel phenotype related to heart failure, especially heart failure with reduced ejection fraction.

Longitudinal association between leisure-time physical activity and vascular elasticity indices

AIM

We investigated the association between levels of leisure-time physical activity and vascular stiffness in a longitudinal observational study from a representative Swedish population.

METHOD

A total of 2816 randomly selected individuals were examined at visit 1 (2002-2005, Men = 1400). After a mean follow-up of 9.7 ± 1.4 years, a representative sample of 1327 of the original participants were re-examined at visit 2. After excluding subjects with hypertension at baseline, 761 participants were included in the longitudinal analyses. Leisure-time physical (LTPA) activity was self-reported and dichotomized as high or low (level 3, 4 and level 1, 2, respectively). Large Arterial Elasticity Index (LAEI) and Small Arterial Elasticity Index (SAEI) were measured using the HDI/Pulse Wave™ CR2000. Multivariable general linear models were used to investigate the differences in changes SAEI and LAEI based on LTPA levels.

RESULTS

At visit 1, and after adjustment for possible confounders, participants in the high LTPA group had better small artery elasticity (SAEI) (SAEI in low-level LTPA: 7.89 ± 0.11, SAEI in high-level LTPA: 8.32 ± 0.15, ΔSAEI: 0.42, CI: 0.07-0.78; p = 0.020). SAEI decreased between the two assessments (Visit 1: SAEI 8.01 ± 3.37 ml/mmHg; Δ SAEI: 1.4, CI 1.2-1.6, p < 0.001). Participants with a higher LTPA at visit 1 had significantly better SAEI at visit 2 (ΔSAEI: 0.44, CI 0.03-0.85, p = 0.037). No significant associations were observed between LAEI and LTPA after adjustments.

CONCLUSIONS

High LTPA predicted higher small arterial compliance at visit 2 suggesting that positive effects of LTPA on arterial elasticity persists over time.

PTC1 and PTC2: New Indices of Blood Pressure Waveforms and Cardiovascular Disease

Systolic and diastolic blood pressures provide information about cardiovascular disease (CVD) but are only extremes of the pressure waveform during the cardiac cycle. We developed summaries of the pressure decay, called PTC1 and PTC2, that are related to arterial compliance and to an existing proprietary summary that has been shown to predict CVD. We derived the summaries from a Windkessel model (consisting of a decaying exponential plus a dampened cosine, with an intercept so they are independent of calibration with blood pressure, unlike the proprietary measures), and we estimated them using nonlinear least squares with standard, free software. Among 6,228 adults from the Multi-Ethnic Study of Atherosclerosis, initially free of CVD in 2000-2002, mean PTC2 was 94 (standard deviation, 46) milliseconds. During median 15-year follow-up, there were 911 CVD events (including 609 incidents of coronary heart disease and 270 strokes). One-standard-deviation higher PTC2 was associated with 17% (95% confidence interval: 10, 24) lower CVD risk, after adjustment for traditional risk factors. Results were similar for PTC1. PTC1 and PTC2 are relatively straightforward to compute and add information beyond traditional risk factors for prediction of CVD. Our work enables others to replicate and extend our results with waveforms from any suitable device.

Immediate post-exercise blood pressure and arterial compliance in middle-aged and older normotensive females: A cross-sectional study

This study examined whether immediate post-exercise systolic blood pressure (SBP) is associated with arterial compliance in middle-aged and older normotensive females. A total of 548 normotensive, non-frail females aged 55 years and older with no previous history of cardiovascular disease (CVD) participated in this cross-sectional study. Large and small arterial compliance were assessed by pulse wave analysis. Reduced arterial compliance was defined based on age and sex cutoffs. SBP was measured at rest and immediately following a 3-min moderate step-test. CVD risk factors were also assessed (e.g. resting systolic and diastolic BP, fasting glucose, triglycerides, cholesterol, body mass index). A total of 15.1% and 44.0% of the participants showed reduced large and small artery compliance, respectively. Immediate post-exercise SBP was associated with reduced large (OR 1.02 per 1 mmHg increase in post-exercise SBP, 95%CI 1.01–1.04; p = 0.010) and small (OR 1.02 per 1 mmHg increase in post-exercise SBP, 95%CI 1.00–1.03; p = 0.008) arterial compliance. Participants with highest immediate post-exercise SBP (quartile 4; i.e. ≥ 165 mmHg) showed increased odds ratios for reduced large (2.67, 95%CI 1.03–6.94; p = 0.043) and small (2.27, 95%CI 1.22–4.21; p = 0.010) arterial compliance compared to those with the lowest immediate post-exercise SBP (quartile 1; i.e. ≤ 140 mmHg), independent of other established CVD risk factors. Immediate post-exercise SBP following a brief moderate step-test seems to be able to discriminate reduced arterial compliance in middle-aged and older normotensive females.

Association of obesity with arterial stiffness: The Multi-Ethnic Study of Atherosclerosis (MESA)

Arterial stiffness (AS) and obesity are recognized as important risk factors of cardiovascular disease (CVD). The purpose of this study was to investigate the relationship between AS and obesity. AS was defined as high augmentation index (AIx) and low elasticity (C1, large artery elasticity; C2, small artery elasticity) in participants enrolled in the Multi-Ethnic Study of Atherosclerosis at baseline. We compared AIx, C1, and C2 by body mass index (BMI) (< 25, 25-29.9, 30-39.9, ⩾ 40 kg/m²) and waist-hip ratio (WHR) (< 0.85, 0.85-0.99, ⩾ 1). The obesity-AS association was tested across 10-year age intervals. Among 6177 participants (62 ± 10 years old, 52% female), a significant inverse relationship was observed between obesity and AS. After adjustments for CVD risk factors, participants with a BMI > 40 kg/m² had 5.4% lower AIx (mean difference [Δ] = -0.82%; 95% CI: -1.10, -0.53), 15.4% higher C1 (Δ = 1.66 mL/mmHg ×10; 95% CI: 1.00, 2.33), and 40.2% higher C2 (Δ = 1.49 mL/mmHg ×100; 95% CI: 1.15, 1.83) compared to those with a BMI < 25 kg/m² (all p for trend < 0.001). Participants with a WHR ⩾ 1 had 5.6% higher C1 (∆ = 0.92 mL/mmHg ×10; 95% CI: 0.47, 1.37) compared to those with a WHR < 0.85. The WHR had a significant interaction with age on AIx and C2, but not with BMI; the inverse relationships of the WHR with AIx and C2 were observed only in participants < 55 years between the normal (WHR < 0.85) and the overweight (0.85 ⩽ WHR < 0.99) groups. Different associations of WHR and BMI with arterial stiffness among older adults should be further investigated.

Early cardiovascular structural and functional abnormalities as a guide to future morbid events

Aims

Our aim was to evaluate the predictive value of a battery of 10 non-invasive tests of cardiovascular structural and functional health on the future risk of cardiovascular morbid events.

Methods and Results

A total of 1900 asymptomatic adults concerned about their risk for cardiovascular disease underwent non-invasive assessment with 10 tests of vascular and cardiac structure and function. A disease score (DS) was calculated for each individual based on these 10 tests. Follow-up (mean 9.2 years) for cardiovascular morbidity and mortality was available for 1442 individuals (mean age 53.2 years, 48.2% women). Those in the lowest DS tertile (0–2) experienced 0.16 cardiovascular events per 100 patient-years (PY), those in the middle tertile (3–5) experienced 0.86 events per 100 PY, and those in the highest tertile (6+) experienced 1.3 events per 100 PY (p &lt; .001). Sensitivity analysis, assuming a neutral effect of DS on projected events in subjects not followed, did not alter statistical significance. Risk assessment using the Framingham risk score (FRS) also predicted morbid events but the two methods differed in identifying individuals at high risk. The net reclassification index was improved by 0.11 (p = 0.01) when DS was added to FRS.

Conclusions

Assessing the biological disease process in the arteries and heart of asymptomatic adults provides a guide to the risk of a future cardiovascular morbid event. Larger and longer studies are needed to determine whether risk factor algorithms, the severity of the biological process or some combination is the optimal method for identifying individuals in need of intervention to delay morbid events.

A prospective controlled study of metabolic and physiologic effects of kidney donation suggests that donors retain stable kidney function over the first nine years

While there have been numerous studies of living kidney donors, most have been retrospective without suitable controls and have yielded conflicting results. To clarify this we studied 205 living donor candidates and 203 controls having no medical conditions precluding donation. Before and at six months, one, two, three, six, and nine years after donation we measured iohexol glomerular filtration rate, clinic blood pressure, urine protein excretion and metabolic parameters reported to be affected by kidney function. We measured 24 hour ambulatory blood pressure at three, six, and nine years and at six and nine years blood pressure after treadmill exercise, carotid-femoral pulse wave velocity and arterial elasticity. Between six months and nine years, the mean (95% confidence interval) change in glomerular filtration rate was significantly different among 133 donors 0·02 (-0·16-0·20) mL/min/1·73m²/year versus -1·26 (-1·52--1·00) mL/min/1·73m²/year in 113 healthy controls. Blood pressure, urine protein, urine albumin, glucose, hemoglobin A1c, insulin, and lipoproteins were not different in controls versus donors; but parathyroid hormone, homocysteine and uric acid remained higher at nine years. At six and nine years carotid-femoral pulse wave velocity was not different, but the mean small artery elasticity was significantly lower in 141 donors 6·1 mL/mmHg x100, versus 113 controls 7·1 mL/mmHg x100, and 6·1 mL/mmHg x100 in 137 donors versus 7·6 mL/mmHg x100 in 112 controls at six and nine years, respectively [significant adjusted difference of 1·1 mL/mmHg x100]. Thus, donors remain healthy with stable kidney function for the first nine years, but differences in metabolic and vascular parameters could be harbingers of adverse outcomes requiring future interventions.

Aerobic training session length affects arterial elasticity

PURPOSE

The purpose of this study was to examine haemodynamic and arterial elasticity responses to aerobic exercise of varying durations.

METHODS

Eighteen male subjects (age = 23·4 ± 2·0) performed a maximal aerobic fitness (VO_2max ) test. Participants met in the laboratory following an overnight fast for three randomly assigned sessions. Assessments for large and small arterial elasticity (SAE), systemic vascular resistance (SVR), total vascular impedance (TVI), systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), stroke volume (SV), cardiac output (CO), pulse pressure (PP) and cardiac ejection time (CET) were performed using applanation tonometry at the radial artery. Following baseline measurements, participants executed aerobic exercise on a treadmill at 65% of their respective VO_2max for 30, 45 or 60 min on three different occasions. Postexercise measurements were performed immediately, 10, 20 and 40 min postexercise cessation.

RESULTS

The 60-min exercise bout resulted in significantly increased SAE values (P < 0·04) and decreased SVR values (P < 0·02) when compared with the 30-min exercise bout. The 60-min session also caused significantly higher HR values and significantly lower values for SV and DBP values following exercise (P < 0·04).

CONCLUSIONS

The results of this study emphasize that varying the length of moderate-intensity aerobic exercise bouts affects arterial elasticity response and total vascular resistance.

Association of C2, a derivative of the radial artery pressure waveform, with new onset of type 2 diabetes mellitus: the MESA study

BACKGROUND

Although microvascular dysfunction is known to result from diabetes, it might also lead to diabetes. Lower values of C2, a derivative of the radial artery pressure waveform, indicate microvascular dysfunction and predict hypertension and cardiovascular disease (CVD). We studied the association of C2 with incident diabetes in subjects free of overt CVD.

METHODS

Among multi-ethnic participants (n = 5214), aged 45-84 years with no diabetes, C2 was derived from the radial artery pressure waveform. Incident diabetes (N = 651) was diagnosed as new fasting glucose ≥ 126 mg/dL or antidiabetic medicine over ~ 10 years. The relative incidence density (RID) for incident diabetes per standard deviation (SD) of C2 was studied during ~ 10 years follow-up using four levels of adjustment.

RESULTS

Mean C2 at baseline was 4.58 ± 2.85 mL/mmHg × 100. The RID for incident diabetes per SD of C2 was 0.90 (95% CI 0.82-0.99, P = 0.03). After adjustment for demographics plus body size, the corresponding RID was 0.81 (95% CI 0.73-0.89, P < 0.0001); body mass index (BMI) was the dominant covariate here. After adjustment for demographics plus cardiovascular risk factors, the RID was 0.98 (95% CI 0.89, 1.07, P = 0.63). After adjustment for all the parameters in the previous models, the RID was 0.87 (95% CI 0.78, 0.96, P = 0.006).

CONCLUSIONS

In a multi-ethnic sample free of overt CVD and diabetes at baseline, C2 predicted incident diabetes after adjustment for demographics, BMI and CVD risk factors. Differences in arterial blood pressure wave morphology may indicate a long-term risk trajectory for diabetes, independently of body size and the classical risk factors.

Living Arrangement: a Contributor to Vascular Disease in Asymptomatic African American Women

BACKGROUND

Diminished social support lias shown to lead to worse cardiovascular outcomes and since cardiovascular disease (CVD) is the leading cause of death in the United States (U.S.), it is critical to non-invasively study its precursor- vascular disease (VD). Assessing the impact social support lias on vascular outcomes can unveil potential CVD susceptibilities in at-risk populations. African American women exhibit the greatest burden of CVD morbidity and mortality; therefore, the purpose of tins study is to examine the association between living arrangement/social support and impaired vascular function in asymptomatic African American women.

METHODS

Vascular function was assessed by a non-invasive screening tool, HDI/PulseWave CR-2000, during screenings at community outreach events on participants clinically free of CVD. Vascular disease was defined as abnormal/impaired vascular function. Living arrangement, a binary variable (living with someone/living alone), was determined by survey responses (N=67) and represented social support. Multivariable analyses were used to estimate adjusted odds ratios (AORs) and 95% confidence intervals (95% CIs) to determine the association between living arrangement and vascular disease after controlling for confounders. Analyses were conducted using SAS 9.2.

RESULTS

Of those who lived alone, 82% had vascular disease (p=0.03). After adjusting for family CVD, and other CVD risk factors, those who lived with a spouse/partner or relative were 78% (p=0.04) less likely to develop vascular disease (AOR=0.22; 95% 0=0.05, 0.98).

CONCLUSIONS

Our study provides preliminary evidence to suggest that among African American women, clinically free of CVD, living arrangement is associated with vascular disease. While living alone may place individuals at an increased risk of CVD because of the association, living with a spouse/partner or relative may act as a protective factor against vascular disease and reduce the risk of CVD. Public health practitioners may use individuals' living arrangement as preventive measure for CVD risk.

"Sleep disordered breathing and ECG R-wave to radial artery pulse delay, The Multi-Ethnic Study of Atherosclerosis"

BACKGROUND

Electrocardiography R-wave to radial artery pulse delay (RRD) represents pulse transit time inclusive of pre-ejection period (PEP) and arterial pulse propagation time. RRD is proposed to largely reflect arterial stiffness when PEP is accounted for (shorter RRD = higher arterial stiffness). Sleep disordered breathing (SDB) causes intermittent hypoxemia and sympathetic activation, which negatively influences vascular function. We aimed to examine the association of measures of SDB with RRD.

METHODS

Our sample consisted of participants in the Multi-Ethnic Study of Atherosclerosis without prevalent cardiovascular disease who underwent a daytime arterial elasticity exam, cardiac magnetic resonance imaging (MRI), and overnight polysomnography. SDB measures of interest included apnea hypopnea index (AHI) and oxygen desaturation index (ODI) (N = 1173). RRD was regressed on each measure of SDB separately, with adjustment for other cardiovascular risk factors as well as for correlates of the PEP, another component of RRD, by including cardiac MRI measures of contractility and preload.

RESULTS

In multivariate analysis, among measures of SDB, ODI, a marker of intermittent hypoxemia, was inversely associated with RRD (β = -60.2 msec per SD [15.5/hr], p = 0.04). No significant association was found with AHI. In gender stratified analyses, ODI and AHI were predictive of RRD in men only (β = -111.3 msec per SD [15.5/hr], p = 0.01 and β = -100.3 msec per SD [16.1/hr], p = 0.02 respectively).

CONCLUSION

Severity of SDB as measured by ODI was associated with RRD, a marker of arterial stiffness. Thus, association of RRD with measures of SDB appears to be gender-dependent.

Collagen biomarkers and subclinical interstitial lung disease: The Multi-Ethnic Study of Atherosclerosis

BACKGROUND

Lung fibrosis is attributed to derangements in extracellular matrix remodeling, a process driven by collagen turnover. We examined the association of two collagen biomarkers, carboxy-terminal telopeptide of collagen type I (ICTP) and amino-terminal propeptide of type III procollagen (PIIINP), with subclinical interstitial lung disease (ILD) in adults.

METHODS

We performed a cross-sectional analysis of 3244 participants age 45-84 years in the Multi-Ethnic Study of Atherosclerosis. Serum ICTP and PIIINP levels were measured at baseline by radioimmunoassay. Subclinical ILD was defined as high attenuation areas (HAA) in the lung fields on baseline cardiac CT scans. Interstitial lung abnormalities (ILA) were measured in 1082 full-lung CT scans at 9.5 years median follow-up. We used generalized linear models to examine the associations of collagen biomarkers with HAA and ILA.

RESULTS

Median (IQR) for ICTP was 3.2 μg/L (2.6-3.9 μg/L) and for PIIINP was 5.3 μg/L (4.5-6.2 μg/L). In fully adjusted models, each SD increment in ICTP was associated with a 1.3% increment in HAA (95% CI 0.2-2.4%, p = 0.02) and each SD increment in PIIINP was associated with a 0.96% increment in HAA (95% CI 0.06-1.9%, p = 0.04). There was no association between ICTP or PIIINP and ILA. There was no evidence of effect modification by gender, race, smoking status or eGFR.

CONCLUSIONS

Higher levels of collagen biomarkers are associated with greater HAA independent of gender, race and smoking status. This suggests that extracellular matrix remodeling may accompany subclinical ILD prior to the onset of clinically evident disease.

Inflammation Associates With Impaired Small Arterial Elasticity Early in HIV Disease

We estimated small arterial elasticity and used linear regression to evaluate its association with inflammatory biomarkers among antiretroviral therapy–naïve, HIV-positive patients with high CD4+ counts. After adjustment, high-sensitivity C-reactive protein and interleukin-6 were inversely associated with small arterial elasticity. These data suggest that systemic inflammation may contribute to vascular dysfunction even in very early HIV disease.

Early changes of arterial elasticity in Type 1 diabetes with microvascular complications - A cross-sectional study from childhood to adulthood

AIM

To examine the trajectory of small artery elasticity (SAE) and pulse pressure (PP) in people with Type 1 diabetes and non-diabetic controls across the lifespan, and explore associations with microvascular complications (CX+).

METHODS

This cross-sectional study included 477 Type 1 diabetes patients (188 with CX+, 289 without CX-) and 515 controls. Relationships between SAE and PP and age were evaluated using segmented linear regression. Logistic regression was used to assess the associations between microvascular complications (retinopathy and/or nephropathy) and SAE and PP.

RESULTS

SAE peaked significantly later among controls than diabetic patients CX- vs. CX+ (21.2 vs. 20.4 vs. 17.6 years respectively, p < 0.001). In adults, mean SAE was significantly lower in CX+ vs. CX- vs. controls (6.8 vs. 7.8 vs. 8.0 ml/mm Hg × 10; p < 0.0001), and mean PP was significantly higher in CX+ vs CX- and controls (60 vs. 55 vs. 53 mm Hg; p < 0.0001).

CONCLUSION

Type 1 diabetes CX+ subjects have an earlier peak and decline in SAE relative to CX- and controls, who did not differ. Lower SAE and higher PP were associated with increased odds of Type 1 diabetes complications in adults. These clinically applicable techniques demonstrate an association between accelerated vascular aging and vascular complications in diabetes.

Effect of nebivolol or atenolol vs. placebo on cardiovascular health in subjects with borderline blood pressure: the EVIDENCE study

Pharmacotherapy to protect the arteries may be appropriate for individuals with high-normal blood pressure who are at risk for future cardiovascular disease (CVD). Nebivolol (NEB) in contrast to atenolol (ATE) may have a beneficial effect on endothelial function and may be more effective than ATE in preventing CVD. Sixty subjects with preHTN or borderline BP and abnormal small artery elasticity (SAE) underwent evaluation with 10 tests, including large and small artery elasticity, resting and treadmill exercise BP, carotid intimal-media thickness, retinal vascular photography, micro-albuminuria, electrocardiography, echocardiography, and plasma B-type natriuretic peptide level. Each test scored as normal (0), borderline (1), or abnormal (2), and the total disease score (DS) was calculated by adding the test scores. Subjects were randomized double-blind to placebo (PLAC, n = 22), NEB 5/10 mg/day (n = 20), or ATE 25/50 mg/day (n = 18) once daily for 9 months. After 9 months, in the group receiving NEB the mean (standard deviation) DS decreased from baseline 4.3 (2.6) to 2.8 (2.4) (P < 0.007), with ATE from 5.4 (2.5) to 3.5 (1.9) (P = 0.0006), and with PLAC from 5.2 (3.0) to 4.5 (2.6) (P = 0.18). SAE increased in the NEB group from 6.0 (2.2) to 8.4 (3.4) ml/mmHg × 100 (P = 0.0001), whereas there was no significant change in the ATE and PLAC groups. Thus, nebivolol improves small artery function more than atenolol in asymptomatic subjects with preHTN or borderline BP, despite their similar BP-lowering effect.

Artery compliance in patients with rheumatoid arthritis: results from a case-control study

Atherosclerosis is one of the most common complications of rheumatoid arthritis (RA). The objective of this study is to evaluate differences in large artery compliance (C1) and small artery compliance (C2) between RA and controls and evaluating factors associated with reduced compliance in the RA population. The profiling of large and small arterial compliance was analyzed in 185 RA patients and 88 healthy controls using Cardiovascular Profiling Instrument. The correlations of arterial compliance and the relevant clinical data were determined in these subjects. Then correlation analysis and regression analysis were performed to find whether rheumatoid arthritis patients have more risk factors than healthy controls in artery compliance and to explore the possible element involved in RA patients including traditional cardiovascular risk factors, RA disease-related factors, and the therapy. Compared with healthy controls, levels of C1 and C2 were significantly decreased in RA patients. Having adjusted the traditional risk factors associated with atherosclerosis, C1 and C2 decline was still a significant indicator in RA patients [odds ratio = 7.411(95%CI 3.275, 16.771) and 10.184(95%CI 4.546, 22.817)]. Using multi-factor regression analysis to adjust traditional risk factors for arterial compliance, we found that the levels of ESR was correlated with the abnormal large artery compliance [odds ratio = 1.021(95%CI 1.007, 1.035)]. The HAQ values and the current usage of leflunomide were correlated with the abnormal small artery compliance in RA patients [odds ratio = 1.161(95%CI 1.046, 1.289) and 6.170(95%CI 1.510, 25.215)]. The values of C1 and C2 are indicators of artery compliance in RA patients. ESR, HAQ values, and the usage of leflunomide might be possible risk factors of artery compliance. The evaluation of artery compliance could be an easy and reliable test that could help us to screen and predict cardiovascular disorders in RA patients.

The impact of dark chocolate intake on arterial elasticity in individuals with HIV/AIDS undergoing ART: a randomized, double-blind, crossover trial

An increase in the frequency of cardiovascular diseases has been observed in the HIV/AIDS population. Studies involving healthy subjects or subjects with other diseases have shown benefits of chocolate supplementation on endothelial function and vasodilation. We evaluate the impact of chocolate consumption on arterial elasticity in people living with human immunodeficiency virus - PLHIV. A double-blind, crossover trial including 110 PLHIV (19 to 59 years) on antiretroviral therapy - ART for at least 6 months and with a viral load of <500 copies per mL was conducted. All subjects were randomly assigned to 15-d dietary supplements containing dark chocolate or placebo with a 15-d washout period. Each participant received one of the two sequences: A (dark chocolate, placebo chocolate); B (placebo chocolate, dark chocolate). Arterial elasticity was measured using the HDI/PulseWave™ CR-2000 CardioVascular Profiling System®. Body composition, lipid profile, C-reactive protein, and thiobarbituric acid reactive substances were also assessed. Analysis of variance (ANOVA) for repeated measures using the Stata 11.0® program was used for cross-over analysis. Most subjects were men (59.0%) and Caucasian (46.1%) and the mean age was 44.6 ± 7.1 years. The mean time since diagnosis of HIV infection was 13.7 ± 5.3 years and the mean duration of ART was 12.9 ± 4.2 years. Chocolate consumption resulted in significant alterations in the large artery elasticity index - LAEI (p = 0.049) and the mean concentration of HDL-c was higher after supplementation with dark chocolate (p = 0.045). This is the first study to evaluate the effect of chocolate on arterial elasticity in PLHIV. The results showed that dark chocolate consumption for 15 days improved the elastic properties of the LAEI in PLHIV. These findings, added to the noninvasive method used, may expand the knowledge of CVDs in this population.

Vascular function in breast cancer survivors on aromatase inhibitors: a pilot study

PURPOSE

Aromatase inhibitors (AI) have been shown to reduce breast cancer-related mortality in women with estrogen positive (ER+) breast cancer. The use of AIs, however, has been associated with higher rates of hypertension, hyperlipidemia, and cardiovascular (CV) events.

METHODS

A cross-sectional study of 25 healthy postmenopausal women and 36 women with curative intent breast cancer on an AI was performed to assess endothelial dysfunction, an indicator of risk for CV events. Consented subjects underwent vascular testing using the HDI/Pulse Wave CR-2000 Cardiovascular Profiling System and the EndoPAT2000 system.

RESULTS

Mean age was 61.7 and 59.6 years (cases, controls). Most subjects were Caucasian and overweight. Controls had a lower mean systolic blood pressure (128.6 mmHg vs. 116.2 mmHg, p = 0.004). Median estradiol levels were reduced in cases (2 vs. 15 pg/ml, p < 0.0001). EndoPAT ratio (0.8 vs. 2.7, p < 0.0001) was significantly reduced in cases as compared to controls. Median large artery elasticity (12.9 vs. 14.6 ml/mmHg × 10, p = 0.12) and small artery elasticity (5.2 vs. 7.0 ml/mmHg × 100, p = 0.07) were also reduced though not statistically significant. There was no correlation between use of chemotherapy, radiation therapy, type of AI, or duration of AI use and endothelial function. When adjusting for differences in blood pressure, results remained significant.

CONCLUSION

Breast cancer cases on AIs have reductions in endothelial function, a predictor of adverse CV disease.

IMPACT

Vascular function changes in breast cancer cases on AIs compared to postmenopausal women. Further work is needed to evaluate vascular changes over time.

Comparing Arterial Function Parameters for the Prediction of Coronary Heart Disease Events: The Multi-Ethnic Study of Atherosclerosis (MESA)

Arterial dysfunction has been linked to decline in cardiac function and increased risk of cardiovascular disease events. We calculated the value of arterial function, measured at baseline (2000-2002), in predicting time to first coronary heart disease (CHD) event (median follow-up, 10.2 years) among participants in the Multi-Ethnic Study of Atherosclerosis (MESA). Measures included the following: C₁ and C₂, derived from diastolic pulse contour analysis from the radial artery blood pressure waveform obtained by tonometry (n = 6,336); carotid distensibility and Young's elastic modulus at the carotid artery, derived from carotid artery ultrasonography (n = 6,531 and 6,528); and aortic distensibility, measured using cardiac magnetic resonance imaging (n = 3,677). After adjustment, the hazard ratio for a CHD event per standard-deviation increment in arterial function was 0.97 (95% confidence interval (CI): 0.86, 1.10) for C₁, 0.73 (95% CI: 0.63, 0.86) for C₂, 0.98 (95% CI: 0.86, 1.11) for carotid distensibility, 0.99 (95% CI: 0.90, 1.09) for Young's modulus, and 0.90 (95% CI: 0.74, 1.10) for aortic distensibility. We examined the area under the receiver operating characteristic curve for the model with full adjustment plus the addition of each measure individually. C₂ provided additional discrimination for the prediction of CHD (area under the curve = 0.736 vs. 0.743; P = 0.04). Lower C₂ was associated with a higher risk of future CHD events.

Effect of omega-3 fatty acid supplementation on arterial elasticity in patients with familial hypercholesterolaemia on statin therapy

BACKGROUND AND AIMS

Increased arterial stiffness is closely linked with raised blood pressure that contributes substantially to enhanced risk of coronary heart disease in high risk individuals with familial hypercholesterolaemia (FH). Omega-3 fatty acid (ω3-FA) supplementation has been demonstrated to lower blood pressure in subjects with a high cardiovascular disease risk. Whether ω3-FA supplementation improves arterial stiffness in FH subjects, on background statin therapy, has yet to be investigated.

METHOD AND RESULTS

We carried out an 8-week randomized, crossover intervention trial to test the effect of 4 g/d ω3-FA supplementation (46% eicosapentaenoic acid and 38% docosahexaenoic acid) on arterial elasticity in 20 adults with FH on optimal cholesterol-lowering therapy. Large and small artery elasticity were measured by pulse contour analysis of the radial artery. ω3-FA supplementation significantly (P < 0.05 in all) increased large artery elasticity (+9%) and reduced systolic blood pressure (-6%) and diastolic blood pressure (-6%), plasma triglycerides (-20%), apoB concentration (-8%). In contrast, ω3-FAs had no significant effect on small artery elasticity. The change in large artery elasticity was not significantly associated with changes in systolic blood pressure or plasma triglyceride concentration.

CONCLUSIONS

ω3-FA supplementation improves large arterial elasticity and arterial blood pressure independent of statin therapy in adults with FH.

CLINICAL TRIAL REGISTRATION

https://www.clinicaltrials.com/NCT01577056.

Early Antiretroviral Therapy at High CD4 Counts Does Not Improve Arterial Elasticity: A Substudy of the Strategic Timing of AntiRetroviral Treatment (START) Trial

Background.

Both human immunodeficiency virus (HIV) infection and antiretroviral therapy (ART) may increase cardiovascular disease (CVD) risk. Vascular function assessments can be used to study CVD pathogenesis. We compared the effect of immediate versus deferred ART initiation at CD4 counts >500 cells/mm³ on small arterial elasticity (SAE) and large artery elasticity (LAE).

Methods.

Radial artery blood pressure waveforms were recorded noninvasively. Small arterial elasticity and LAE were derived from analysis of the diastolic pulse waveform. Randomized treatment groups were compared with linear models at each visit and longitudinal mixed models.

Results.

Study visits involved 332 participants in 8 countries: mean (standard deviation [SD]) age 35 (10), 70% male, 66% nonwhite, 30% smokers, and median CD4 count 625 cells/mm³ and 10-year Framingham risk score for CVD 1.7%. Mean (SD) SAE and LAE values at baseline were 7.3 (2.9) mL/mmHg × 100 and 16.6 (4.1) mL/mmHg × 10, respectively. Median time on ART was 47 and 12 months in the immediate and deferred ART groups, respectively. The treatment groups did not demonstrate significant within-person changes in SAE or LAE during the follow-up period, and there was no difference in mean change from baseline between treatment groups. The lack of significant differences persisted after adjustment, when restricted to early or late changes, after censoring participants in deferred group who started ART, and among subgroups defined by CVD and HIV risk factors.

Conclusions.

Among a diverse global population of HIV-positive persons with high CD4 counts, these randomized data suggest that ART treatment does not have a substantial influence on vascular function among younger HIV-positive individuals with preserved immunity.

Circulating Des-gamma-carboxy prothrombin is not associated with cardiovascular calcification or stiffness: The Multi-Ethnic Study of Atherosclerosis (MESA)

BACKGROUND AND AIMS

Vitamin K-dependent protein (VKDP) activity may have a role in preventing cardiovascular calcification, but has not previously been studied in large, generally healthy populations.

METHODS

Using an elevated ankle-brachial index (ABI) as a measure of medial vascular calcification, we performed a case-cohort analysis within the Multi-Ethnic Study of Atherosclerosis, measuring Des-gamma-carboxy prothrombin (DCP) to estimate VKDP activity. In secondary analyses of the weighted subcohort, we examined the cross-sectional associations between DCP and prevalent vascular calcification of the coronary vessels, aortic and mitral valves, and aortic wall, and with vascular stiffness.

RESULTS

In adjusted analysis, cases (n = 104) had 0.21 ng/ml (-0.94-0.52) lower DCP concentrations than the subcohort (n = 613). Furthermore, amongst the 717 participants in the weighted cohort, VKDP activity was not associated with coronary artery, mitral valve, aortic valve or aortic wall calcification, nor was it associated with vascular stiffness.

CONCLUSIONS

Our negative results do not support a role of circulating VKDP activity in cardiovascular calcification in community-dwelling adults.

Differences in galectin-3, a biomarker of fibrosis, between participants with peripheral artery disease and participants with normal ankle-brachial index

The aim of this study was to determine if galectin-3 levels were different between participants with peripheral artery disease (PAD) and controls, and to describe its relationship with markers of early atherosclerosis. Sixty participants were recruited into two groups: a PAD group (n=31), ankle-brachial index (ABI) ⩽0.90 and a normal ABI group (n=29), ABI 1.0-1.4. PAD participants were older (68.6 vs 61.8 years, p=0.037), more commonly men (68% vs 38%, p=0.02), and with more cardiovascular risk factors (p<0.001). Galectin-3 was 22% higher in PAD participants (mean±SD: 17.6±4.7 vs 14.4±4.1 ng/mL, p<0.01). The odds ratio for galectin-3 in PAD to be 1 ng/mL higher than the participants with normal ABI was 1.19, after adjusting by age and gender (p=0.014). High-sensitivity C-reactive protein (hs-CRP) and homeostatic model assessment (HOMA) were positively associated with galectin-3 in the age- and gender-adjusted model, while arterial elasticity and microalbuminuria were not. In conclusion, galectin-3 levels were higher in participants with PAD.

Invited Commentary: Hypertension and Arterial Stiffness--Origins Remain a Dilemma

In this issue of the Journal, Chen et al. (Am J Epidemiol. 2016;183(7):599-608) present repeated measures of aorto-femoral pulse wave velocity, capacitive compliance (C1), and oscillatory compliance (C2) in the Bogalusa Heart Study, with the purpose of addressing which comes first: blood pressure elevation or arterial stiffening. After an average follow-up period of 7 years (2000-2010), the authors found that blood pressure at a mean age of 36 years predicted change in arterial stiffening by a mean age of 43 years, but not the reverse. Essential hypertension results from a mosaic of pathological mechanisms. It has been theorized that biological pathways involving increased sympathetic tone, insulin resistance, renin-angiotensin-aldosterone activation, and inflammation lead to hyperkinetic circulation, volume overload, and vascular remodeling. The resultant accelerated vascular aging may be assessed by determining the degree of arterial stiffness. The findings of Chen et al. add important empirical information to the literature but do not solve the dilemma regarding the origins of essential hypertension, partly because there are many techniques for estimating the many aspects of arterial stiffness which are not fully understood. Mathematical features of estimates might not be uniform across the age range. There is a need for tracking blood pressure and different aspects of arterial stiffness from childhood onward, with an aim of preventing hypertension in adult life.

Temporal Relationship Between Elevated Blood Pressure and Arterial Stiffening Among Middle-Aged Black and White Adults: The Bogalusa Heart Study

This study assessed the temporal relationship between elevated blood pressure (BP) and arterial stiffness in a biracial (black-white) cohort of middle-aged adults aged 32-51 years from the semirural community of Bogalusa, Louisiana. Measurements of aortic-femoral pulse wave velocity (afPWV; n = 446) and large- and small-arterial compliance (n = 381) were obtained at 2 time points between 2000 and 2010, with an average follow-up period of 7 years. A cross-lagged path analysis model was used to examine the temporal relationship of elevated BP to arterial stiffness and elasticity. The cross-lagged path coefficients did not differ significantly between blacks and whites. The path coefficient (ρ2) from baseline BP to follow-up afPWV was significantly greater than the path coefficient (ρ1) from baseline afPWV to follow-up BP (ρ2 = 0.20 vs. ρ1 = 0.07 (P = 0.048) for systolic BP; ρ2 = 0.19 vs. ρ1 = 0.05 (P = 0.034) for diastolic BP). The results for this 1-directional path from baseline BP to follow-up afPWV were confirmed, although marginally significant, by using large- and small-artery elasticity measurements. These findings provide strong evidence that elevated BP precedes large-artery stiffening in middle-aged adults. Unlike the case in older adults, the large-arterial wall is not stiff enough in youth to alter BP levels during young adulthood.

Oxidative stress, inflammation, endothelial dysfunction and incidence of type 2 diabetes

BACKGROUND

Oxidative stress, inflammation and endothelial dysfunction are interrelated factors in the etiology of cardiovascular disease, but their linkage to type 2 diabetes is less clear. We examined the association of these biomarkers with incident type 2 diabetes (T2D).

METHODS

Analysis of 2339 participants in the community-based coronary artery risk development in young adults (CARDIA) study. Participants (age 40.1 ± 3.6 years, 44 % Black, 58 % women) were free of diabetes, and were followed 10 years. Cox regression was used to estimate hazard ratios (HRs) for incident T2D adjusting for the other biomarkers under study, demographic and lifestyle measures, dietary biomarkers, BMI (kg/m(2)) and metabolic syndrome components.

RESULTS

F2-isoprostanes and oxidized LDL (oxidative stress) were positively associated with incident T2D, but the associations were attenuated by adjustment for BMI. C-reactive protein was positively associated with T2D even with full adjustment: HR (95 % CI) = 2.21 (1.26-3.88) for quartile 4 (Q4) v. quartile 1 (Q1). The HR (95 % CI) for T2D for biomarkers of endothelial dysfunction ICAM-1 and E-selectin for Q4 v. Q1 were 1.64 (0.96-2.81) and 1.68 (1.04-2.71) respectively, with full adjustment. Including these two markers in a common risk score incorporating BMI and clinical measures improved the prediction probability of T2D: relative risk for the average person classified up compared to the average person classified down: 1.09, (1.06-1.13), P < 0.0001.

CONCLUSIONS

Biomarkers of inflammation and endothelial dysfunction were positively associated with incident T2D. ICAM-1 and E-selectin add to the prediction of T2D beyond a common risk score.

A combined measure of vascular risk for white matter lesions

BACKGROUND

Though hypertension is a commonly studied risk factor for white matter lesions (WMLs), measures of blood pressure may fluctuate depending on external conditions resulting in measurement error. Indicators of arterial stiffening and reduced elasticity may be more sensitive indicators of risk for WMLs in aging; however the interdependent nature of vascular indicators creates statistical complications.

OBJECTIVE

The purpose of the study was to determine whether a factor score comprised of multiple vascular indicators would be a stronger predictor of WMLs than traditional measures of blood pressure.

METHODS

In a sample of well-characterized nondemented older adults, we used a factor analytic approach to account for variance common across multiple vascular measures while reducing measurement error. The result was a single factor score reflecting arterial stiffness and reduced elasticity. We used this factor score to predict white matter lesion volumes acquired via fluid attenuated inversion recovery (FLAIR) magnetic resonance imaging.

RESULTS

The combined vascular factor score was a stronger predictor of deep WML (β = 0.42, p < 0.001) and periventricular WML volumes (β = 0.49, p < 0.001). After accounting for the vascular factor, systolic and diastolic blood pressure measurements were not significant predictors.

CONCLUSIONS

This suggests that a combined measure of arterial elasticity and stiffening may be a stronger predictor of WMLs than systolic and diastolic blood pressure accounting for the multicollinearity associated with a variety of interrelated vascular measures.

Recognition and Management of Hypertension in Older Persons: Focus on African Americans

Hypertension is the most commonly diagnosed condition in persons aged 60 and older and is the single most important risk factor for cardiovascular disease (ischemic heart disease, heart failure, and stroke), kidney disease, and dementia. More than half of individuals with hypertension in the United States are aged 60 and older. Hypertension disproportionately affects African Americans, with all age groups, including elderly adults, having a higher burden of hypertension-related complications than other U.S.

POPULATIONS

Multiple clinical trials have demonstrated the beneficial effects of blood pressure (BP) reduction on cardiovascular morbidity and mortality, with most of the evidence in individuals aged 60 and older. Several guidelines have recently been published on the specific management of hypertension in individuals aged 60 and older, including in high-risk groups such as African Americans. Most recommend careful evaluation, thiazide diuretics and calcium-channel blockers for initial drug therapy in most African Americans, and angiotensin-converting enzyme inhibitors and angiotensin receptor blockers in those with chronic kidney disease or heart failure. Among the areas of controversy is the recommended target BP in African Americans aged 60 and older. A recent U.S. guideline recommended raising the systolic BP target from less than 140 mmHg to less than 150 mmHg in this population. This article will review the evidence and current guideline recommendations for hypertension treatment in older African Americans, including the rationale for continuing to recommend a SBP target of less than 140 mmHg in this population.

Associations of kidney injury markers with subclinical cardiovascular disease: the Multi-Ethnic Study of Atherosclerosis

No abstract available.

Protective role of dairy and its constituents on vascular function independent of blood pressure-lowering activities

Greater intakes of dairy are frequently associated with reduced risk of cardiovascular disease. These observational studies have served as the basis for controlled interventions aimed at defining the cardioprotective mechanisms of dairy. Understanding these relationships is of public health importance because most of the US population fails to meet dietary recommendations for dairy, suggesting that many individuals could lower their cardiovascular disease risk by relatively simple dietary modification. Clinical studies investigating the acute ingestion of dairy or its constituents, including short-term (≤2 week) supplementation studies or those assessing postprandial responses, have largely shown benefits on vascular function without concomitant improvements in blood pressure. Chronic interventions have been less conclusive, with some showing benefits and others indicating a lack of improvement in vascular function regardless of blood pressure changes. Vasoprotective activities of dairy are likely mediated through improvements in nitric oxide bioavailability, oxidative stress, inflammation, and insulin resistance. Future controlled studies are needed to determine if these health benefits are mediated directly by dairy or indirectly by displacing other dietary components that otherwise impair vascular health.

Assessment of arterial elasticity among HIV-positive participants with high CD4 cell counts: a substudy of the INSIGHT Strategic Timing of AntiRetroviral Treatment (START) trial

OBJECTIVES

Both HIV infection and antiretroviral therapy (ART) may increase cardiovascular disease (CVD) risk. Assessments of vascular function and structure can be used to study the pathogenesis and progression of CVD, including the effects of ART and other interventions. The objective of this report is to understand methods to assess vascular (dys)function and report our experience in the Arterial Elasticity Substudy in the Strategic Timing of AntiRetroviral Treatment (START) trial.

METHODS

We review literature and analyze baseline data from the Arterial Elasticity Substudy, which estimated vascular (dys)function through analysis of the diastolic blood pressure (BP) waveform. Linear regression was used to study cross-sectional associations between baseline clinical factors and small or large arterial elasticity.

RESULTS

Arterial elasticity measurement was chosen for its improved measurement reproducibility over other methodologies and the potential of small arterial elasticity to predict clinical risk. Analysis of baseline data demonstrates that small artery elasticity is impaired (lower) with older age and differs by race and between geographical regions. No HIV-specific factors studied remained significantly associated with arterial elasticity in multivariate models.

CONCLUSIONS

Longitudinal analyses in this substudy will provide essential randomized data with which to study the effects of early ART initiation on the progression of vascular disease among a diverse global population. When combined with future biomarker analyses and clinical outcomes in START, these findings will expand our understanding of the pathogenesis of HIV-related CVD.

Associations of body composition measures and C2, a marker for small artery elasticity: The MESA

OBJECTIVE

Lower C2, a continuous blood pressure waveform characteristic asserted to represent small artery elasticity, predicts future cardiovascular disease events. It is hypothesized that the paradoxical positive association between body mass index (BMI) and C2 may reflect muscle instead of excess fat.

METHODS

In a multi-ethnic, community-living cohort of 1,960 participants, computed tomography scans of the abdomen were used to measure visceral adipose tissue (VAT) and total abdominal muscle tissue (TAMT), and applanation tonometry of the radial arteries was used to assess C2. The period cross-sectional associations between BMI, TAMT, and VAT with C2 were ascertained.

RESULTS

The mean age was 62 ± 9 years and 51% were male. After adjustments for age, gender, ethnicity, pack years smoking cigarettes, diabetes, hypertension, and total and HDL cholesterol, higher BMI (standardized beta = 0.09, P-value < 0.01) and more TAMT (standardized beta = 0.12, P-value < 0.01) were significantly associated with higher C2. In contrast, more VAT (standardized beta = -0.09, P-value < 0.01) was associated with lower C2.

CONCLUSIONS

In multivariable analysis, VAT, in contrast to TAMT and BMI, was associated with less compliant small arteries. Visceral fat may be a better marker for detrimental excess body fat than BMI.

Baseline characteristics of African Americans in the Systolic Blood Pressure Intervention Trial

The Systolic Blood Pressure Intervention Trial (SPRINT) will compare treatment to a systolic blood pressure goal of <120 mm Hg to treatment to the currently recommended goal of <140 mm Hg for effects on incident cardiovascular, renal, and neurologic outcomes including cognitive decline. The objectives of this analysis are to compare baseline characteristics of African American (AA) and non-AA SPRINT participants and explore factors associated with uncontrolled blood pressure (BP) by race. SPRINT enrolled 9361 hypertensive participants aged older than 50 years. This cross-sectional analysis examines sociodemographics, baseline characteristics, and study measures among AAs compared with non-AAs. AAs made up 31% of participants. AAs (compared with non-AAs) were younger and less frequently male, had less education, and were more likely uninsured or covered by Medicaid. In addition, AAs scored lower on the cognitive screening test when compared with non-AAs. Multivariate logistic regression analysis found BP control rates to <140/90 mm Hg were higher for AAs who were male, had higher number of chronic diseases, were on diuretic treatment, and had better medication adherence. SPRINT is well poised to examine the effects of systolic blood pressure targets on clinical outcomes as well as predictors influencing BP control in AAs.

Arterial elasticity in obese adolescents with clinical features of insulin resistance

OBJECTIVE

To determine whether arterial elasticity differs between obese adolescents with clinical insulin resistance (IR), type 1 diabetes (T1D) and healthy non-obese controls.

METHODS

This cross-sectional study evaluated 69 adolescents with clinical IR, 91 with T1D and 63 age-matched (10- to 18-year-old) controls. Arterial elasticity was measured using radial tonometry pulse-wave analysis. Stepwise multiple regression analyses were performed to assess the determinants of the small and large arterial elasticity indices (SAEI and LAEI).

RESULTS

SAEI and LAEI raw values were higher in the IR group than the controls, and these did not differ between the T1D and control groups. Weight and diastolic blood pressure (DBP) were significant predictors of SAEI. After adjustment for weight and DBP, SAEI decreased by 0.65 mL/mmHg × 100 for each 1-year increase in age in the IR group. SAEI was not different across the groups after controlling for weight and DBP. Height was the strongest predictor of LAEI which remained higher in the IR group after controlling for height and blood pressure.

CONCLUSION

Obese adolescents with clinical IR have a higher SAEI, which declines with age; this may reflect a pathway to an increased risk of premature cardiovascular disease.

Heart failure risk across the spectrum of ankle-brachial index: the ARIC study (Atherosclerosis Risk In Communities)

OBJECTIVES

The aim of this study was to describe the relationship between ankle brachial index (ABI) and the risk for heart failure (HF).

BACKGROUND

The ABI is a simple, noninvasive measure associated with atherosclerotic cardiovascular disease and death; however, the relationship between ABI and risk for HF is less well characterized.

METHODS

Between 1987 and 1989 in the ARIC (Atherosclerosis Risk In Communities) study, an oscillometric device was used to measure blood pressure in a single upper and randomly chosen lower extremity to determine the ABI. Incident HF events were defined by the first hospitalization with an International Classification of Diseases, Ninth Revision, code of 428.x through 2008. The risk for HF was assessed across the ABI range using restricted cubic splines and Cox proportional hazards models.

RESULTS

ABI was available in 13,150 participants free from prevalent HF. Over a mean 17.7 years of follow-up, 1,809 incident HF events occurred. After adjustment for traditional HF risk factors, prevalent coronary heart disease, subclinical carotid atherosclerosis, and interim myocardial infarction, compared with an ABI of 1.01 to 1.40, participants with ABIs ≤0.90 were at increased risk for HF (hazard ratio: 1.40; 95% confidence interval: 1.12 to 1.74), as were participants with ABIs of 0.91 to 1.00 (hazard ratio: 1.36; 95% confidence interval: 1.17 to 1.59).

CONCLUSIONS

In a middle-age community cohort, an ABI ≤1.00 was significantly associated with an increased risk for HF, independent of traditional HF risk factors, prevalent coronary heart disease, carotid atherosclerosis, and interim myocardial infarction. Low ABI may reflect not only overt atherosclerosis but also pathologic processes in the development of HF beyond epicardial atherosclerotic disease and myocardial infarction alone. A low ABI, as a simple, noninvasive measure, may be a risk marker for HF.

Prognostic impact of arterial stiffness in patients with symptomatic peripheral arterial disease

OBJECTIVES

Arterial stiffness (AS) is increasingly recognized as an independent risk factor in different high-risk populations. Whether changes in AS can predict prognosis in patients with symptomatic peripheral arterial disease (PAD) has never been investigated. The aim of the present study was to test the hypothesis that AS is an independent predictor of all-cause and cardiovascular disease (CVD) mortality in patients with symptomatic PAD.

METHODS

A cohort of 117 symptomatic PAD patients (aged 62.3 ± 7.7 years) were prospectively recruited from the Department of Vascular Surgery, Tartu University Hospital, between 2002 and 2010. The AS was measured using pulse wave analysis and assessment of pulse wave velocity (PWV).

RESULTS

During the follow-up period (mean 4.1 ± 2.2 years) there were 32 fatal events. Kaplan-Meier analysis showed that the probability of all-cause and CVD mortality decreased with increasing small artery elasticity (SAE), as estimated by the log-rank test (p = .004; p = .005, respectively). By contrast, large artery elasticity, augmentation index, and aortic and brachial PWV were not significantly related to mortality. In a Cox proportional hazard model, SAE above the median was associated with decreased all-cause and CVD mortality after adjustment for confounding factors: relative risk (RR), 0.37; 95% confidence interval (CI), 0.17-0.81; p = .01; RR, 0.11; 95% CI, 0.01-0.86; p = .04, respectively).

CONCLUSIONS

This study provides the first evidence, obtained from an observational study, that decreased small artery elasticity is an independent predictor of all-cause and CVD mortality in patients with symptomatic PAD.