Guan-Jin Ho

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.

Inverse association of serum long-acting natriuretic peptide and bone mineral density in renal transplant recipients.

Hsu B‐G, Ho G‐J, Lee C‐J, Yang Y‐C, Chen Y‐C, Shih M‐H, Lee M‐C. Inverse association of serum long‐acting natriuretic peptide and bone mineral density in renal transplant recipients. 
Clin Transplant 2011 DOI: 10.1111/j.1399‐0012.2011.01575.x. 
© 2011 John Wiley & Sons A/S.

Serum Sclerostin as an Independent Marker of Peripheral Arterial Stiffness in Renal Transplantation Recipients: A Cross-Sectional Study.

AbstractWnt/&bgr;-catenin signaling pathway is thought to be implicated in the development of arterial stiffness and vascular calcification. As a Wnt signaling pathway inhibitor, it is interesting to investigate whether sclerostin or dickkopf-1 (DKK1) level is correlated with arterial stiffness in renal transplant (RT) recipients. Fasting blood samples were obtained for biochemical data, sclerostin, DKK1, and osteoprotegerin (OPG) determinations. In this study, we applied automatic pulse wave analyzer (VaSera VS-1000) to measure brachial-ankle pulse wave velocity and either sides of brachial-ankle pulse wave velocity value, which greater than 14.0 m/s was determined as high arterial stiffness. Among 68 RT recipients, 30 patients (44.1%) were in the high arterial stiffness group. Compared with patients in the low arterial stiffness group, patients in the high arterial stiffness group had higher prevalence of hypertension (P = 0.002), diabetes (P < 0.001), metabolic syndrome (P = 0.025), longer posttransplant duration (P = 0.005), higher systolic blood pressure (P < 0.001) and diastolic blood pressure (P = 0.018), and higher fasting glucose (P = 0.004), total cholesterol (P = 0.042), blood urea nitrogen (P = 0.020), phosphorus (P = 0.042), and sclerostin levels (P = 0.001). According to our multivariable forward stepwise linear regression analysis, age (&bgr; = 0.272, P = 0.014), phosphorus (&bgr; = 0.308, P = 0.007), and logarithmically-transformed OPG (log-OPG; &bgr; = 0.222, P = 0.046) were positively associated with sclerostin levels, and multivariate logistic regression analysis, sclerostin (odds ratio 1.052, 95% confidence interval 1.007–1.099, P = 0.024), and posttransplant duration (odds ratio 1.024, 95% confidence interval 1.004–1.045, P = 0.019) were the independent predictors of peripheral arterial stiffness in RT recipients. In this study, serum sclerostin level, but not DKK1, was proved to be involved in the pathogenetic process of peripheral arterial stiffness in RT recipients.

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

Abstract 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; R2 = 0.205, p = 0.001) and body weight (β = 0.327; R2 = 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.

Associations Between High Serum Adipocyte Fatty Acid Binding Protein and First Hospitalization in Kidney Transplantation Patients

Introduction Adipocyte fatty acid-binding protein (A-FABP) is an adipokine and predicts the incidence of metabolic syndrome and type 2 diabetes mellitus and is an independent association with atherosclerosis. This study was evaluated the association between serum A-FABP levels and future first hospitalization events in patients with kidney transplantation (KT). Materials and Methods A total of 72 KT patients were enrolled in this study from January through April 2012. The primary end point was the incidence of first hospitalization. All patients are follow-up until June 2017.Fasting blood samples were obtained from 74 KT patients. Serum A-FABP levels were determined using a commercially available enzyme immunoassay. Results During a median 65-month follow-up, Forty-nine first hospitalization events occurred. Compared with serum median A-FABP levels, female KD patient had higher A-FABP levels(P = 0.033) and serum A-FABP level was positively associated with body mass index (P = 0.036), body fat mass (P = 0.004), systolic blood pressure (P = 0.003), total cholesterol (P = 0.014), triglyceride (P = 0.010), blood urea nitrogen (P = 0.001), creatinine (P = 0.032), while negatively associated with height (P = 0.029), glomerular filtration rate (P = 0.008), respectively. KT patients with first hospitalization events and higher prevalence of diabetes (P = 0.027), hypertension (P = 0.049), higher body fat mass (P = 0.024), and higher serum A-FABP levels (P = 0.011) compared to subjects without first hospitalization events. The Kaplan–Meier analysis showed that the cumulative incidence of the first hospitalization events in the high A-FABP group (median A-FABP concentration of ≥ 29.05 ng/mL) was greater than that in the low A-FABP group (log-rank P = 0.018). By multivariate Cox analysis showed that hypertension (hazard ratio (HR): 2.134, 95% confidence interval (CI): 1.190–3.828, P = 0.011) and serum A-FABP levels (HR: 1.010, 95% CI: 1.000–1.019, P = 0.047) was independently associated with first hospitalization events in KT patients. Conclusion The results of our study showed that the serum A-FABP level is a biomarker for future first hospitalization events in KT patients. Further prospective studies are needed to confirm the mechanisms underlying this association. Figure. No caption available.

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.

C-reactive Protein Positively Correlates With Metabolic Syndrome in Kidney Transplantation Patients

Objective C-reactive protein (CRP) is an independent risk factor for renal allograft loss and predicts all-cause mortality in kidney transplantation patients. Metabolic syndrome has also been associated with increased mortality in kidney transplantation patients. The aim of this study was to investigate the relationship between CRP and metabolic syndrome in kidney transplantation patients. Materials and Methods Fasting blood samples were obtained from 55 kidney transplantation patients. Metabolic syndrome and its components were defined using diagnostic criteria from the International Diabetes Federation. Results In total, 13 kidney transplantation patients (23.6%) had metabolic syndrome. Fasting CRP levels positively correlated with metabolic syndrome ( p = 0.001). Univariate linear regression analysis indicated that fasting serum CRP values were positively correlated with body weight ( p = 0.001), waist circumference ( p = 0.008), body mass index ( p p = 0.042). Multivariate forward stepwise linear regression analysis of the significant variables showed that body mass index (β = 0.455, R 2 = 0.207, p Conclusion CRP level positively correlated with metabolic syndrome in kidney transplantation patients. Body mass index was an independent predictor of serum CRP levels in kidney transplantation patients .