Association of Serum Osteoprotegerin Levels With Carotid‐Femoral Pulse Wave Velocity in Hypertensive Patients

Circulating calcification inhibitors are associated with arterial damage in pediatric patients with primary hypertension

BACKGROUND

Circulating calcification inhibitors: fetuin A (FA) and osteoprotegerin (OPG) together with soluble ligand of receptor activator of nuclear factor kappa-B (sRANKL) have been linked to vascular calcifications and arterial damage. This study aimed to evaluate relationships between FA, OPG, sRANKL, and arterial damage in children with primary hypertension (PH).

METHODS

In this cross-sectional single-center study, calcification inhibitors (FA, OPG, sRANKL) levels were measured in blood samples of 60 children with PH (median age 15.8, IQR: [14.5-16.8] years) and 20 age-matched healthy volunteers. In each participant, peripheral and central blood pressure evaluation (BP) and ambulatory BP monitoring (ABPM) were performed. Arterial damage was measured using common carotid artery intima media thickness (cIMT), pulse wave velocity (PWV), augmentation index (AIx75HR), and local arterial stiffness (ECHO-tracking-ET) analysis.

RESULTS

Children with PH had significantly higher peripheral and central BP, BP in ABPM, thicker cIMT, higher PWV, and AIx75HR. FA was significantly lower in patients with PH compared to healthy peers without differences in OPG, sRANKL, and OPG/sRANKL and OPG/FA ratios. In children with PH, FA level correlated negatively with cIMT Z-score and ET AIx; sRANKL level correlated negatively with ABPM systolic blood pressure (SBP), SBP load, diastolic BP load, and AIx75HR; OPG/sRANKL ratio correlated positively with SBP load, while OPG/FA ratio correlated positively with ET AIx. In multivariate analysis, FA was a significant determinant of cIMT (mm) and cIMT Z-score.

CONCLUSIONS

This study reveals that in children with primary hypertension, arterial damage is related to lower fetuin A concentrations.

Serum Osteoprotegerin and Carotid Intima-Media Thickness Are Related to High Arterial Stiffness in Heart Failure with Reduced Ejection Fraction

Arterial stiffness (AS) is a complex vascular phenomenon with consequences for central hemodynamics and left-ventricular performance. Circulating biomarkers have been associated with AS; however, their value in heart failure is poorly characterized. Our aim was to evaluate the clinical and biomarker correlates of AS in the setting of heart failure with reduced ejection fraction (HFrEF). In 78 hospitalized, hemodynamically stable patients (20 women, 58 men, mean age 65.8 ± 1.41 years) with HFrEF, AS was measured using aortic pulse wave velocity (PWV). Serum OPG, RANKL, sclerostin, and DKK-1 were determined, and the relationships between the clinical variables, vascular-calcification-related biomarkers, and PWV were evaluated by correlation analysis and linear and logistic regression models. OPG and the OPG/RANKL ratio were significantly higher in the group of patients (n = 37, 47.4%) with increased PWV (>10 m/s). PWV was positively correlated with age, left-ventricular ejection fraction, and carotid intima-media thickness (cIMT), and negatively correlated with the glomerular filtration rate. OPG and cIMT were significantly associated with PWV in the logistic regression models when adjusted for hypertension, EF, and the presence of atherosclerotic manifestations. Elevated serum OPG, together with cIMT, were significantly related to increased AS in the setting of HFrEF.

Association of Low Serum l-Carnitine Levels with Aortic Stiffness in Patients with Non-Dialysis Chronic Kidney Disease

l-carnitine (LC) is a co-factor in fatty acid metabolism; its role with respect to aortic stiffness (AS) associated with chronic kidney disease (CKD) was unclear. Our aim was to investigate associations between serum LC levels and AS in patients with non-dialysis CKD stage 3–5. The AS patients were those with carotid-femoral pulse wave velocities (cfPWV) >10 m/s; those with cfPWV ≤10 m/s were included as controls. Serum LC was measured by liquid chromatography and mass spectrometry. Of 136 CKD patients, the 44 (32.4%) with AS were older, exhibited higher rates of diabetes, and had elevated diastolic and systolic blood pressures (SBP), elevated fasting glucose levels and lower levels of serum LC compared to controls. Multivariable logistic regression revealed that serum LC (odds ratio [OR] = 0.949, 95% confidence interval [CI] 0.911–0.988, p = 0.011) and age (OR = 1.055, 95% CI 1.013–1.099, p = 0.009) were independent predictors of AS. Multivariable stepwise linear regression revealed significant positive (age and SBP) and negative (serum LC) correlations with cfPWV. The area under the curve of serum LC as a means to predict AS in CKD patients was 0.657 (95% CI 0.571–0.736, p = 0.0009). We concluded that low serum LC is a significant predictor of AS in patients diagnosed with CKD.

Serum Malondialdehyde-Modified Low-Density Lipoprotein Is a Risk Factor for Central Arterial Stiffness in Maintenance Hemodialysis Patients

Circulating malondialdehyde-modified low-density lipoprotein (MDA-LDL) acts as a marker of oxidative stress and is associated with atherosclerotic cardiovascular disease. The relationship between serum MDA-LDL levels and aortic stiffness (AS) in patients with hemodialysis (HD) was evaluated. There were 155 HD patients enrolled in this study. Carotid-femoral pulse wave velocity (cfPWV) was measured by a validated tonometry system. Patients with cfPWV >10 m/s were used to define the AS group, while those with values of ≤10 m/s were regarded as the control group. Serum MDA-LDL levels were measured using a commercial enzyme-linked immunosorbent assay. Sixty-eight patients (43.9%) who were defined as AS sufferers, and were older, had a higher percentage of diabetes and hypertension and higher systolic blood pressure and serum MDA-LDL level compared to subjects in the control group. After adjusting for factors significantly associated with AS by multivariable logistic regression analysis, it was revealed that serum MDA-LDL levels, diabetes, and hypertension were independent predictors of AS in HD patients. Multivariable forward stepwise linear regression analysis also showed that a logarithmically transformed MDA-LDL level was significantly correlated with cfPWV values in HD patients. In HD patients, a high serum MDA-LDL level was positively associated with cfPWV values and was a significant predictor of the development of high AS.

Serum Sclerostin But Not DKK-1 Correlated with Central Arterial Stiffness in End Stage Renal Disease Patients

Sclerostin and dickkopf-1 (DKK1) played a role in the development of cardiovascular diseases and arterial stiffness in chronic kidney disease (CKD) patients but with controversial results of patients in end-stage renal disease (ESRD) including hemodialysis (HD) and peritoneal dialysis (PD). This study aimed to examine the association between the mode of dialysis or the values of sclerostin or DKK1 and carotid-femoral pulse wave velocity (cfPWV) in ESRD patients. There were 122 HD and 72 PD patients enrolled in this study. By a validated tonometry system, cfPWV was measured and then segregated patients into values of >10 m/s as the high central arterial stiffness (AS) group and values ≤ 10 m/s as the control group. Serum levels of sclerostin and DKK1 were measured using a commercial enzyme-linked immunosorbent assay kit. Possible risk factors for the development of AS were analyzed by logistic regression analysis. There were 21 (29.2%) of PD and 53 (43.4%) of HD in the high AS group. Compared to patients in the control group, those in the high AS group were older, had more comorbidities, had higher systolic blood pressure, and had higher serum levels of fasting glucose, C-reactive protein, and sclerostin. Levels of sclerostin (adjusted OR 1.012, 95% CI. 1.006–1.017, p = 0.0001) was found to be an independent predictor of high AS in ESRD patients by multivariate logistic regression analysis. Furthermore, receiver operating characteristic curve analysis showed the optimal cut-off values of sclerostin for predicting AS was 208.64 pmol/L (Area under the curve 0.673, 95% CI: 0.603–0.739, p < 0.001). This study showed that serum levels of sclerostin, but not DKK1 or mode of dialysis, to be a predictor for high central AS in ESRD patients.

Serum P-Cresyl Sulfate Is a Predictor of Central Arterial Stiffness in Patients on Maintenance Hemodialysis

Arterial stiffness (AS) has an important impact on the outcomes of patients on hemodialysis (HD), and p-cresyl sulfate (PC) can mediate the process of vascular damage. We aimed to investigate the relationship between carotid-femoral pulse wave velocity (cfPWV) and the level of PCs in HD patients. Serum PCs were quantified using liquid chromatography mass spectrometry. Patients who were on standard HD for more than 3 months were enrolled and categorized according to the cfPWV into the high AS (>10 m/s) and control (≤10 m/s) groups. Forty-nine (41.5%) patients belonged to the high AS group and had a higher incidence of diabetes mellitus (DM) and increased systolic blood pressure, serum C-reactive protein, and PC levels but had lower creatinine, compared with those in the control group. In HD patients, the risk for developing high AS increased in the presence of DM (OR 4.147, 95% confidence interval (CI) 1.497-11.491) and high PCs (OR 1.067, 95% CI 1.002-1.136). Having DM (r = 0.446) and high PC level (r = 0.174) were positively associated with cfPWV. The most optimal cutoff value of PC for predicting AS was 18.99 mg/L (area under the curve 0.661, 95% CI 0.568-0.746). We concluded that DM and PCs were promising predictors of high AS in patients on maintenance HD.

Serum osteoprotegerin is an independent marker of central arterial stiffness as assessed using carotid-femoral pulse wave velocity in hemodialysis patients: a cross sectional study

Background

Cardiovascular morbidity and mortality are highly prevalent in patients with end-stage renal disease, and osteoprotegerin (OPG) may be an important link between bone loss and vascular calcification. This study was conducted to evaluate the relationship between central arterial stiffness and serum OPG levels in hemodialysis (HD) patients.

Methods

Blood samples were collected from 120 HD patients, and the carotid–femoral pulse wave velocity (cfPWV) value was measured using a validated tonometry system. The cfPWV value of > 10 m/s was used to define the high artery stiffness group. Serum OPG levels were analyzed categorically into tertiles.

Results

Of the 120 HD patients, 53 (44.2%) were defined as the high arterial stiffness group, who had higher values of systolic blood pressure (p = 0.038), serum calcium (p = 0.007), and OPG (p <  0.001) levels and a higher prevalence of diabetes mellitus (DM, p = 0.001). Increasing tertiles of serum OPG levels were significantly associated with greater height (p = 0.011), male gender (p = 0.008), higher cfPWV values (p = 0.020), and lower intact parathyroid hormone (iPTH, p = 0.049) levels. Multivariable linear regression analysis showed that cfPWV value was independently associated with DM (β = 1.83, p = 0.008) and increasing tertiles of serum OPG levels (β = 0.89 and 1.63 for tertile 2 and tertile 3, respectively, p for trend = 0.035) in HD patients. Multivariable logistic regression analysis revealed that, in addition to age, DM, low iPTH levels, and high serum calcium levels, increasing tertiles of serum OPG levels (OR = 5.34 for tertile 2; OR = 7.06 for tertile 3; p for trend = 0.002) were an independent predictor of high arterial stiffness in HD patients. Serum calcium levels positively correlated with cfPWV value only in the highest OPG tertile group (r = 0.408, p = 0.009).

Conclusion

A positive association was detected between serum OPG levels and central arterial stiffness in HD patients, and patients with high serum OPG levels may have greater influence of calcium load on central arterial stiffening.

Osteocalcin and carotid-femoral pulse wave velocity in patients on peritoneal dialysis

Objective

Vascular calcification is a cardiovascular risk factor in dialysis patients. Vascular calcification involves a complex process of biomineralization resembling osteogenesis, which leads to arterial stiffness. Osteocalcin is the most abundant noncollagenous protein in the bone matrix. It is synthesized in the bone by osteoblasts and reflects the rate of bone formation. The aim of this study was to evaluate the relationship between serum osteocalcin levels and the carotid-femoral pulse wave velocity (cfPWV) in peritoneal dialysis (PD) patients.

Materials and Methods

Serum intact osteocalcin and cfPWV were measured in 62 PD patients. Those with CfPWV values >10 m/s were defined as the high central arterial stiffness group, while those with values ≤10 m/s were regarded as the low central arterial stiffness group, according to the European Society of Hypertension and of the European Society of Cardiology guidelines.

Results

Seventeen of the 62 PD patients (27.4%) were in the high central arterial stiffness group. The high central arterial stiffness group were older (P = 0.002), had a longer PD vintage (P = 0.018), and had higher serum osteocalcin levels (P = 0.001) than those in the low group. Multivariate logistic regression analysis showed that the osteocalcin level (odds ratio: 1.069, 95% confidence interval (CI): 1.005-1.137, P = 0.035), PD vintage (odds ratio: 1.028, 95% CI: 1.010-1.048, P = 0.003), and age (odds ratio: 1.081, 95% CI: 1.005-1.162, P = 0.035) were independently associated with central arterial stiffness in PD patients. Among these patients, cfPWV (β: 0.216, P = 0.001) values and log-transformed intact parathyroid hormone (β: -'0.447, P < 0.001) levels were independently associated with the osteocalcin level in PD patients after multivariate forward stepwise linear regression analysis.

Conclusion

Older PD patients with a longer PD vintage and higher serum osteocalcin levels had higher central arterial stiffness as measured by cfPWV. The serum osteocalcin level is an independent marker of central arterial stiffness in PD patients.

Serum leptin is a predictor for central arterial stiffness in hypertensive patients

AIM

Serum adipokines have a role in the development of arterial stiffness. We aimed to investigate the risk factors of developing arterial stiffness and the association of leptin and arterial stiffness in hypertensive (HTN) patients.

METHODS

There were 101 HTN patients enrolled. Fasting blood samples and baseline characteristics were obtained and carotid-femoral pulse wave velocity (cfPWV) was measured with the SphygmoCor system. A cfPWV > 10 m/s was defined as high arterial stiffness, and ≤ 10 m/s as low arterial stiffness.

RESULT

Forty-seven patients (46.5 %) had high arterial stiffness, and had a higher percentage of diabetes (P = 0.044), , older age (P < 0.001), higher pulse pressure (P = 0.049), and higher serum blood urea nitrogen (P = 0.029), creatinine (P = 0.027), intact parathyroid hormone (P = 0.004), serum leptin level (P = 0.002), C-reactive protein (P < 0.001), but lower estimated glomerular filtration rate (P = 0.006) compared to patients with low arterial stiffness. After adjusting for factors significantly associated with arterial stiffness by multivariate logistic regression analysis, it revealed that leptin (aOR = 1.037, 95% CI = 1.007-1.067, P = 0.014), having DM (aOR = 4.885, 95% CI = 1.590-15.006, P = 0.006), and elevated CRP (aOR = 1.503, 95% CI = 1.110-2.0371,P = 0.009) were significant independent predictors of arterial stiffness in HTN patients.

CONCLUSIONS

Serum leptin level could be a predictor for arterial stiffness in HTN patients.

The Role of Osteoprotegerin as a Cardioprotective Versus Reactive Inflammatory Marker: the Chicken or the Egg Paradox

Cardiovascular disease is one of the most frequent causes of mortality and morbidity worldwide. Several variables have been identified as risk factors for cardiovascular disease. Recently, the role of receptor activator of nuclear factor kappa B, receptor activator of nuclear factor kappa B ligand, and the osteoprotegerin system has been recognized as more important in the pathogenesis of cardiovascular disease. Besides their roles in the regulation of bone resorption, these molecules have been reported to be associated with the pathophysiology of cardiovascular disease. There are conflicting data regarding the impact of osteoprotegerin, a glycoprotein with a regulatory role in the cardiovascular system. The aim of this review is to discuss the current knowledge and the role of osteoprotegerin in cardiovascular disease.

Negative Correlation of Serum Adiponectin Levels With Carotid–Femoral Pulse Wave Velocity in Patients Treated With Hemodialysis

Purpose:

The aim of this study was to evaluate the relationship between serum adiponectin levels and carotid–femoral pulse wave velocity (cfPWV) in hemodialysis (HD) patients.

Method:

Blood samples were obtained from 120 HD patients. cfPWV was measured with a validated tonometry system (SphygmoCor; AtCor Medical, West Ryde, Australia). Serum adiponectin levels were measured using a commercially available enzyme-linked immunosorbent assay kit.

Results:

By univariate linear analysis of cfPWV in HD patients, we found that diabetes ( r = .281, p = .002), pre-HD body weight ( r = .194, p = .033), post-HD body weight ( r = .192, p = .036), waist circumference ( r =.210, p = .022), and body fat mass ( r = .194, p = .034) were positively correlated, whereas adiponectin level ( r = −.254, p = .005) was negatively correlated with cfPWV in HD patients. Multivariate forward stepwise linear regression analysis showed that diabetes (β = .274, p = .006) and adiponectin level (β = −.215, p = .016) were independent predictors of cfPWV in HD patients. Moreover, post-HD body weight (β = −.274, p = .041), waist circumference (β = −.311, p < .001), logarithmically transformed triglyceride level (log-TG; β = −.186, p = .031), and log-glucose (β = −.225, p = .008) were negatively associated with adiponectin levels in HD patients after multivariable forward stepwise linear regression analysis.

Conclusions:

Among HD patients, serum adiponectin level was inversely associated with cfPWV level, and post-HD body weight, waist circumference, log-TG, and log-glucose were negatively associated with adiponectin level.

Hyperleptinemia positively associated with central arterial stiffness in hemodialysis patients

Objective

Leptin plays a role in stimulating vascular inflammation, vascular smooth muscle hypertrophy, and augmenting blood pressure, which contributes to the pathogenesis of atherosclerosis and leads to arterial stiffness. This vascular damage, measured by carotid-femoral pulse wave velocity (cfPWV), is recognized as an independent predictor of cardiovascular mortality in hemodialysis (HD) patients. The aim of this study was to evaluate the relationship between serum leptin and arterial stiffness in HD patients.

Patients and methods

In 112 of the 126 HD patients were eligible and their biochemical data were collected for analysis. Serum leptin level was measured using a commercial enzyme-linked immunosorbent assay kit. Carotid-femoral pulse wave velocity was measured by a validated tonometry system (SphygmoCor). Those have cfPWV values above 10 m/s are defined as the high arterial stiffness group.

Results

Among the participants, thirty-eight of them who were in the high arterial stiffness group, had a higher prevalence of diabetes mellitus (p = 0.002), age (p = 0.029), body mass index (BMI, p = 0.018), body fat mass (p = 0.001), hemoglobin (p = 0.040), and serum leptin levels (P<0.001). Multivariable logistic regression analysis showed that leptin (odds ratio [OR] 1.09; 95% confidence interval [CI] 1.04–1.14; p <0.001), diabetes (OR 7.17; CI 1.39–37.00; p = 0.019), body fat mass (OR 1.16; CI 1.02–1.33; p = 0.027); and hemoglobin (OR 2.11; CI 1.15–3.87; p = 0.015) were independently associated with arterial stiffness in HD patients.

Conclusion

In our study, hyperleptinemia was positively correlated to the high cfPWV and thus was related to high arterial stiffness in HD patients.

Elevated serum osteoprotegerin may predict peripheral arterial disease after kidney transplantation: a single-center prospective cross-sectional study in Taiwan

Background

Osteoprotegerin (OPG) is a potential biomarker for severity and complications of cardiovascular diseases. Peripheral arterial disease (PAD) is associated with an increased risk of death in kidney transplantation (KT) patients. This prospective cross-sectional study evaluated the relationship between serum OPG and PAD in KT patients.

Methods

Seventy-four KT patients were enrolled for this PAD study. Fasting blood samples were obtained to measure serum OPG levels by using enzyme-linked immunosorbent assay kits. The ankle-brachial index (ABI) of less than 0.9 was applied for PAD diagnosis.

Results

Thirteen patients (17.6%) were diagnosed with PAD. Diabetes (P = 0.025), smoking (P = 0.010), and increased OPG levels (P = 0.001) were significantly more frequent in the PAD group. Multivariate logistic regression analysis showed that serum OPG (odds ratio [OR], 1.336; 95% CI [1.108–1.611]; P = 0.002) and diabetes (OR, 7.120; 95% CI [1.080–46.940]; P = 0.041) were independent predictors of PAD in KT patients. The area under the receiver operating characteristic (ROC) curve determined that the probability of a serum OPG level of 7.117 pg/L in predicting PAD in KT patients was 0.799 (95% CI [0.690–0.884]; P < 0.001).

Discussion

Exploration of reliable biomarkers for early identification of vascular risk is crucial for KT patients. Elevated serum OPG levels may predict PAD in KT patients with cutoff value of 7.117 pg/L.

High serum adipocyte fatty acid binding protein level as a potential biomarker of aortic arterial stiffness in hypertensive patients with metabolic syndrome

BACKGROUND

The adipocyte-fatty-acid-binding protein (A-FABP) has been implicated in arterial stiffness, metabolic syndrome (MetS), and cardiovascular disease. We aimed to determine the relationship among serum A-FABP concentration, cardiometabolic risk factors, and central arterial stiffness in a hypertensive population.

METHODS

Fasting blood samples and baseline characteristics were obtained from 110 hypertensive patients. Serum A-FABP concentrations were determined by enzyme immunoassay kit. High arterial stiffness was defined as carotid-femoral pulse wave velocity values >10m/s via the SphygmoCor system.

RESULTS

Patients with MetS and high arterial stiffness accounted for 67.3% and 42.7% of the study population, respectively. Serum A-FABP was positively associated with MetS and high arterial stiffness (P=0.006 and P<0.001, respectively). Multivariable stepwise linear regression analysis of the significant variables of arterial stiffness revealed that logarithmically transformed A-FABP (log-A-FABP, β=0.278, P=0.002) was positively correlated arterial stiffness in hypertensive patients. Subgroup analysis revealed that log-A-FABP (β=0.327, P=0.003), age (β=0229, P=0.032), and triglyceride (β=0.307, P=0.004) were significantly positively correlated with arterial stiffness in hypertensive patients with MetS.

CONCLUSIONS

Elevated A-FABP concentration could be a predictor for MetS and arterial stiffness in hypertensive patients.

Serum resistin as an independent marker of aortic stiffness in patients with coronary artery disease

Background

Subjects with higher carotid–femoral pulse wave velocity (cfPWV) will be at an increased risk for cardiovascular (CV) events in future. Resistin is an inflammatory mediator and a biomarker of CV diseases. We evaluated the association between serum resistin and aortic stiffness in patients with coronary artery disease (CAD).

Methods

A total of 104 patients with CAD were enrolled in this study. cfPWV was measured using the SphygmoCor system. Patients with cfPWV >10 m/s were defined as the high aortic stiffness group.

Results

Thirty-seven patients (35.6%) had high aortic stiffness and higher percentages of diabetes (p = 0.001), were of older age (p = 0.001) and had higher waist circumference (p < 0.001), systolic blood pressure (p = 0.027), pulse pressure (p = 0.013), high-sensitivity C-reactive protein (p < 0.001) and resistin levels (p < 0.001) but lower estimated glomerular filtration rate (p = 0.009) compared to subjects with low aortic stiffness. After adjusting for factors significantly associated with aortic stiffness by multivariate logistic regression analysis, serum resistin (odds ratio = 1.275, 95% confidence interval: 1.065–1.527, p = 0.008) was also found to be an independent predictor of aortic stiffness in patients with CAD.

Conclusions

Serum resistin level is a biomarker for aortic stiffness in patients with CAD.

Does the OPG/RANKL system contribute to the bone-vascular axis in chronic kidney disease? A systematic review

Vascular calcification (VC) is highly prevalent in patients with chronic kidney disease (CKD) and is strongly associated with cardiovascular mortality and morbidity. Accumulating evidence over the past decade has challenged the hypothesis of close interaction between bone and VC what raises the possibility of a common underlying pathophysiological mechanism. Lately, bone regulatory proteins such as: osteoprotegerin (OPG) and Receptor Activator for Nuclear Factor κB Ligand (RANKL) has attracted attention of researchers as a possible key mediators of bone-vascular calcification imbalance. The literature search was carried out using the MEDLINE/PubMed database and a combination of keywords and MeSH terms, and only papers published since January 2005 to July 2016 were selected. The search resulted in 562 potential articles. After selection according to the eligibility criteria, 107 studies fulfilled were included (102 full texts and 5 was case reports). OPG and RANKL plays essential role in the regulation of bone metabolism and may be regarded as a possible link between VC, bone and mineral metabolism in CKD patients. Further studies are required to determine the diagnostic significance of these proteins in evaluation of progression and severity of VC process in CKD patients. Finally, the efficacy and safety, especially in regard to VC, of anti-RANKL therapy in CKD patients requires well-designed prospective, randomized trials.

Circulating miR-92a expression level in patients with essential hypertension: a potential marker of atherosclerosis

MicroRNAs (miRs) are key posttranscriptional regulators of gene expression in all eukaryotic cells and have a vital role in the evolution of hypertension and cardiovascular remodelling and, therefore, have emerged as potential biomarkers for cardiovascular disease. We assessed 240 participants, including 60 healthy volunteers with normal carotid intima-media thickness (nCIMT), 60 healthy volunteers with increased CIMT (iCIMT), 60 hypertensive patients with nCIMT and 60 hypertensive patients with iCIMT. All patients underwent measurements of CIMT, carotid-femoral pulse wave velocity (cfPWV) and ambulatory blood pressure (BP) monitoring. Plasma miR-92a expression was quantified by real-time reverse transcription PCR. Correlations between miR-92a expression and BP parameters, CIMT and cfPWV were assessed using the Spearman correlation coefficient. We observed the lowest miR-92a expression (24.59±1.30 vs 27.76±2.13 vs 29.29±1.89 vs 33.76±2.08; P<0.001) in healthy controls with nCIMT, followed by healthy controls with iCIMT, then hypertensive patients with nCIMT and the highest expression in hypertensive patients with iCIMT. Additionally, MiR-92a levels showed a significant positive correlation with 24-h mean systolic BP (r=0.807, P<0.001), 24-h mean diastolic BP (r=0.649, P<0.001), 24-h mean pulse pressure (PP) (r=0.697, P<0.001), 24-h daytime PP (r=0.654, P<0.001), 24-h nighttime PP (r=0.573, P<0.001), CIMT (r=0.571, P<0.001) and cfPWV (r=0.601, P<0.001). Our data present significant evidence that circulating miR-92a represents a potential noninvasive atherosclerosis marker in essential hypertensive patients.

Association of serum leptin levels with central arterial stiffness in coronary artery disease patients

Background

Serum adipokines have roles in the development of arterial stiffness. Our aim was to investigate the relationship of leptin and the surrogate marker carotid-femoral pulse wave velocity (cfPWV) in coronary artery disease (CAD) patients.

Methods

Fasting blood samples were obtained from 105 CAD patients. cfPWV was measured with the SphygmoCor system. A cfPWV > 10 m/s was defined as high arterial stiffness, and ≤ 10 m/s as low arterial stiffness.

Results

Thirty-seven patients (35.2 %) had high arterial stiffness, and had a higher percentage of diabetes (P = 0.001), hypertension (P = 0.010), older age (P = 0.001), and higher systolic blood pressure (SBP) (P < 0.001), diastolic blood pressure (DBP) (P = 0.021), pulse pressure (P = 0.014), and serum leptin level (P = 0.002) compared to patients with low arterial stiffness. Serum leptin levels correlated with the number of angiographically documented stenotic coronary artery vessels (P < 0.001). After adjusting for factors significantly associated with arterial stiffness, multivariate logistic regression analysis showed that leptin (odds ratio = 1.026, 95 % confidence interval: 1.002–1.051, P = 0.037) was a significant independent predictor of arterial stiffness.

Conclusions

Increasing serum concentration of leptin correlated positively with the total number of stenotic coronary arteries, and serum leptin level may predict the development of arterial stiffness in CAD patients.

Hyperleptinemia Is a Risk Factor for the Development of Central Arterial Stiffness in Kidney Transplant Patients

BACKGROUND

Arterial stiffness could cause adverse outcomes in kidney transplant (KT) patients. Leptin has a role in influencing vascular smooth muscle that may contribute to atherosclerosis. The aim of this study was to evaluate the relationship between fasting serum leptin concentration and carotid-femoral pulse wave velocity (cfPWV) in KT patients.

MATERIALS AND METHODS

Fasting blood samples were obtained from 55 KT patients and 65 subjects from the outpatient department were enrolled as the control group. The cfPWV values of >10 m/s were used to define as the high arterial stiffness group and <10 m/s as the low arterial stiffness group. The predictive ability of leptin for arterial stiffness of KT was assessed using receiver operating characteristic (ROC) curve and multivariate logistic regression analyses.

RESULTS

Kidney transplant patients had lower hemoglobin, but higher blood urea nitrogen, creatinine, total cholesterol, diastolic blood pressure, intact parathyroid hormone levels, and leptin levels than controls. Although cfPWV levels were higher in KT patients, there is no difference of cfPWV levels between KT patients and control (P = .595). Fifteen KT patients (27.3%) were defined in the high arterial stiffness group, and serum leptin level was higher in the high arterial stiffness group compared with the low arterial stiffness group in KT patients (P < .001). Multivariate logistic regression analysis showed that leptin (odds ratio: 1.044, 95% confidence interval [CI]: 1.016-1.072, P = .002) was an independent predictor of arterial stiffness in KT patients. The sensitivity, specificity, positive predictive value, negative predictive value, and area under the ROC curve predicting arterial stiffness in KT patients were 73.33%, 87.5%, 68.7%, 89.7%, and 0.828 (95% CI: 0.703-0.917, P < .001), and the leptin cut-off value was 74.14 ng/mL.

CONCLUSION

Serum fasting leptin level could predict the development of central arterial stiffness of KT patients.

High Serum Osteoprotegerin Is Associated with Arterial Stiffness in Kidney Transplant Patients

Osteoprotegerin (OPG) is a cytokine that regulates bone resorption by inhibiting osteoclastogenesis, and OPG has been implicated in the process that causes vascular stiffness. An increase in serum OPG level has been associated with the development of arterial stiffness. Kidney transplant (KT) patients are susceptible to aortic stiffness, which is considered to be a predictor of cardiovascular events in this patient population. Carotid-femoral pulse wave velocity (cfPWV) has emerged as a gold standard for non-invasive evaluation of aortic stiffness. The aim of this study was to evaluate the relationship between serum OPG concentration and cfPWV among KT patients. Fasting blood samples were obtained from 57 KT patients and their cfPWV was measured using applanation tonometry. The serum OPG levels were measured using an enzyme-linked immunosorbent assay. Univariable linear regression analysis showed that the cfPWV in KT patients was significantly and positively correlated with age, body weight, waist circumference, body mass index, log-creatinine, systolic blood pressure, diastolic blood pressure, pulse pressure, and the log-OPG concentration. KT patients with metabolic syndrome had higher cfPWV values than those without metabolic syndrome (P = 0.036), which indicates a higher incidence of aortic stiffness in this patient population. Multivariable forward stepwise linear regression analysis of the significant variables showed that the log-OPG (P = 0.001), the log-creatinine (P = 0.004), and the SBP (P = 0.005) remained as independent and positive predictors of cfPWV values. These findings indicate that serum OPG levels are positively associated with cfPWV in KT patients.

Serum adiponectin is a negative predictor of central arterial stiffness in kidney transplant patients

BACKGROUND

The role of adiponectin in arterial stiffness and its relationship to cardiovascular disease is not fully demonstrated and needs further elaboration. In this study, the association between adiponectin level and arterial stiffness is studied among kidney transplant patients.

MATERIAL AND METHODS

Anthropometric data and biochemical data including fasting glucose, lipid profile, renal function and serum adiponectin were determined in 55 kidney transplant patients. Central arterial stiffness was measured and presented by carotid-femoral pulse wave velocity.

RESULTS

Univariate linear analysis showed that body weight, waist circumference, brachial pulse pressure and body mass index were correlated positively with carotid-femoral pulse wave velocity in this patient group. However, logarithmically transformed adiponectin level (log-adiponectin) correlated negatively with carotid-femoral pulse wave velocity. In multivariate regression analysis of factors significantly associated with carotid-femoral pulse wave velocity, it showed that both log-adiponectin (β = -0.427; R(2) = 0.205, p = 0.001) and body weight (β = 0.327; R(2 )=( )0.106, p = 0.007) were independently predictive of central arterial stiffness.

CONCLUSION

Our study suggests that fasting serum adiponectin is negatively associated with carotid-femoral pulse wave velocity, hence arterial stiffness, in kidney transplant patients.

Serum osteoprotegerin levels associated with the aortic augmentation index in renal transplant recipients

Objectives:

Arterial stiffness is recognized as an independent risk factor for cardiovascular morbidity and mortality. Recent studies found that osteoprotegerin (OPG) is associated with arterial stiffness and may reflect endothelial dysfunction. The aim of this study was to evaluate the relationship between fasting serum OPG levels and the aortic augmentation index (AIx) in renal transplant recipients.

Materials and methods:

Fasting blood samples were obtained from 66 renal transplant recipients. The aortic AIx was measured using a validated tonometry system (SphygmoCor). Serum OPG levels were measured using a commercial enzyme-linked immunosorbent assay kit.

Results:

Univariate linear analysis of the aortic AIx in renal transplant recipients revealed that body fat mass (r = 0.377, p = 0.002), aortic diastolic blood pressure (DBP; r = 0.307, p = 0.020), triglycerides (r = 0.260, p = 0.035), and logarithmically transformed OPG (log-OPG, r = 0.402, p < 0.001) were positively correlated, whereas height (r = 0.361, p = 0.004) and body weight (r = 0.212, p = 0.041) were negatively correlated with the aortic AIx in renal transplant recipients. Multivariate forward stepwise linear regression analysis of the factors significantly associated with the aortic AIx showed that log-OPG (R² = 0.213, p < 0.001), height (R² = 0.081, p = 0.009), and aortic DBP (R² = 0.058, p = 0.022) were independent predictors of the aortic AIx in renal transplant recipients.

Conclusion:

These results suggest that the serum fasting OPG level is associated with the aortic AIx in renal transplant recipients.

Positive correlation of serum adipocyte fatty acid binding protein levels with carotid-femoral pulse wave velocity in geriatric population

Background

Adipocyte fatty acid binding protein (A-FABP) is a novel fat-derived circulating protein, which is independently and positively associated with atherosclerosis. The present study evaluated the relationship between fasting serum A-FABP and central arterial stiffness in geriatric adults.

Methods

Fasting blood samples were obtained from 87 geriatric patients and the serum A-FABP levels were measured using an enzyme immunoassay. Carotid-femoral pulse wave velocity (cfPWV) was determined using the SphygmoCor system. cfPWV values of >10 m/s represented the high arterial stiffness group, while values ≤10 m/s defined the low arterial stiffness group.

Results

High arterial stiffness group comprised of 42 geriatric adults (48.3 %). When compared to those in the low arterial stiffness group, the high arterial stiffness group had a higher rate of diabetes mellitus (P = 0.044) and hypertension (P = 0.043). Body weight (P = 0.027), waist circumference (P = 0.035), body mass index (P = 0.001), systolic blood pressure (P = 0.005), diastolic blood pressure (P = 0.045), pulse pressure (P = 0.038), and serum A-FABP level (P < 0.001) were also higher in the high arterial stiffness group than in the low arterial stiffness group. Multivariate logistic regression analysis of the factors significantly associated with arterial stiffness revealed that A-FABP (odds ratio: 1.833, 95 % confidence interval 1.123–2.993, P = 0.015) was an independent predictor of arterial stiffness in geriatric adults.

Conclusions

Serum A-FABP levels constitute a major risk factor in the development of central arterial stiffness in the geriatric population.

Serum osteoprotegerin is associated with arterial stiffness assessed according to the cardio-ankle vascular index in hypertensive patients

AIM

Arterial stiffness is recognized to be an independent risk factor for cardiovascular morbidity and mortality. Recent studies have found that osteoprotegerin (OPG) is associated with increased pulse wave velocity and may reflect endothelial dysfunction. The aim of this study was to evaluate the relationship between the serum OPG level and arterial stiffness in hypertensive patients using the cardio-ankle vascular index (CAVI).

METHODS

Fasting blood samples were obtained from 115 hypertensive patients and 52 healthy participants. The CAVI value was derived using the waveform device (CAVI-VaSera VS-1000). The serum OPG levels were measured using a commercially available enzyme-linked immunosorbent assay. A CAVI value of ≥9 defined the high arterial stiffness group.

RESULTS

Sixty-five hypertensive patients (56.5%) were included in the high arterial stiffness group. Diabetes (p=0.032), smoking (p=0.044), age (p < 0.001), systolic blood pressure (p=0.001), diastolic blood pressure (p=0.024), pulse pressure (p=0.046) and the creatinine (p=0.013) and serum OPG (p < 0.001) levels were higher in the high arterial stiffness group than in the low arterial stiffness group, while the glomerular filtration rate (p=0.003) was lower in the high arterial stiffness group than in the low arterial stiffness group among the hypertensive patients. The results of the Spearman's rank correlation coefficient test also indicated a strong positive correlation between the OPG and CAVI values (r=0.484, p < 0.001) in the hypertensive patients. In addition, a multivariate logistic regression analysis showed that age (odds ratio: 1.162, 95% confidence interval (CI): 1.070-1.263, p < 0.001), diastolic blood pressure (odds ratio: 1.109, 95% CI: 1.033-1.190, p=0.004), and serum OPG level (odds ratio: 1.275, 95% CI: 1.030-1.580, p=0.026) were independent predictors of arterial stiffness in hypertensive patients.

CONCLUSIONS

The serum OPG level is positively associated with arterial stiffness in hypertensive patients.

Serum osteopontin level correlates with carotid-femoral pulse wave velocity in geriatric persons

Osteopontin (OPN) is involved in the regulation of vascular calcification processes. The aim of this study was to evaluate the relationship between fasting serum OPN concentration and carotid-femoral pulse wave velocity (cfPWV) in geriatric persons. Fasting blood samples were obtained from 93 geriatric persons. cfPWV were performed by SphygmoCor system. Serum OPN levels were measured using a commercially available enzyme-linked immunosorbent assay. Geriatric adults who had diabetes (P = 0.007) or dyslipidemia (P = 0.029) had higher cfPWV levels than those without diabetes or dyslipidemia. The univariable linear regression analysis showed that age (P = 0.002), waist circumference (P = 0.048), body mass index (P = 0.004), systolic blood pressure (P = 0.001), diastolic blood pressure (P = 0.036), pulse pressure (P = 0.017), creatinine (P = 0.002), and log-OPN level (P = 0.001) were positively correlated with cfPWV levels, while the high-density lipoprotein cholesterol (HDL-cholesterol) level (P = 0.007) and glomerular filtration rate (P = 0.001) were negatively correlated with cfPWV levels among the geriatric adults. Multivariable forward stepwise linear regression analysis of the significant variables also showed that log-OPN (β = 0.233, R (2) = 0.123, regression coefficient: 1.868, P = 0.011) was still an independent predictor of cfPWV levels in geriatric persons.