Pretransplant Pregnancy-Associated Plasma Protein-A as a Predictor of Chronic Allograft Nephropathy and Posttransplant Cardiovascular Events

Pregnancy-associated plasma protein A as a predictor of all-cause mortality and cardiovascular events in patients with chronic kidney disease: a meta-analysis of prospective studies

INTRODUCTION

The aim of the study was to assess the association of elevated serum pregnancy associated plasma protein A (PAPP-A) and the risk of all-cause mortality, cardiovascular events and mortality due to infection in patients with chronic kidney disease (CKD).

MATERIAL AND METHODS

We systematically searched the Medline database up to March 2017. A random effects model was used to pool the relative risks (RRs) and their 95% confidence intervals (CIs). Sensitivity analysis and subgroup analysis were performed to explore the potential sources of heterogeneity.

RESULTS

Six studies involving 2034 subjects were included. The pooled RRs for the risk of all-cause mortality and cardiovascular events were 1.50 (95% CI: 1.17-1.92), 1.26 (95% CI: 0.95-1.69), respectively. Sensitivity analysis by excluding each individual study showed no influence on the main results. Subgroup analysis showed that age, male proportion, follow-up term, and assay methods were not modifiable factors.

CONCLUSIONS

Our study suggests that elevated serum PAPP-A is associated with the risk of all-cause mortality in patients with CKD.

Evaluation of Serum Interleukin-6 Levels in the Renal Transplant Recipients: A Systematic Review and Meta-Analysis of Case-Control Studies

AIM:

The purpose of this meta-analysis was the assessment of the serum IL-6 levels in the renal transplant recipients compared to the healthy controls.

MATERIAL AND METHODS:

Four databases including PubMed, Web of Science, Scopus, and Cochrane Library were searched up to July 2018 without language restriction. The quality of studies was evaluated using the Newcastle-Ottawa scale (NOS). A continuous random-effects meta-analysis was used by RevMan 5.3 using the mean difference (MD) and 95% confidence intervals (CIs). Also, a regression model was done by Comprehensive Meta-Analysis version 2 (CMA v2).

RESULTS:

Out of 615 studies identified in the databases, 15 studies included and analysed in the meta-analysis. The studies were reported from 1994 to 2018. The meta-analysis included 1035 renal transplant recipients and 682 healthy controls. The pooled MD of the serum IL-6 levels in the transplant recipients compared to the healthy controls was 3.25 pg/mL [95%CI: 2.17, 4.32; P < 0.00001; I2 = 98% (P < 0.00001)]. Meta-regression analysis showed that one of the reasons of heterogeneity is the year of publication (Correlation coefficient (r) = 0.208, p-value = 0.00002).

CONCLUSION:

An elevated serum IL-6 level in the renal transplant recipients compared to the healthy controls showed that the serum level of this marker could be used for the evaluation of inflammation in ESRD patients undergoing renal transplantation.

Pregnancy associated plasma protein-A as a prognostic biomarker of all-cause mortality and cardiovascular events in patients presenting with chest pain: a systematic review

AIM

Novel biomarkers have been proposed for identification of patients at greater risk of future adverse events among those presenting with chest pain. In this review, we aim to elucidate the ability of pregnancy associated plasma protein-A (PAPP-A) to predict mortality and other cardiovascular events in this patient population.

METHODS

A literature search of the electronic databases Medline, Scopus, Cochrane Library and ClinicalTrials.gov was performed in order to identify studies investigating the utility of PAPP-A to predict mortality and adverse cardiovascular events in patients with chest pain.

RESULTS

Eight studies met our inclusion criteria. Five of these studies pertained to patients with confirmed ischemic chest pain, while the rest included patients presenting with chest pain possibly due to acute coronary syndrome, irrespectively of the underlying cause. Although the results for long-term events were inconclusive in both groups of patients, higher PAPP-A concentrations were found to be a significant predictor of short-term adverse events in patients with confirmed ischemic chest pain.

CONCLUSIONS

PAPP-A appears to be a potentially useful biomarker for short-term risk stratification of patients presenting with chest pain of ischemic origin. However, there is an eminent need for more standardized clinical studies investigating the prognostic value of this biomarker.

Pregnancy-associated plasma protein A associates with cardiovascular events in diabetic hemodialysis patients

OBJECTIVE

Pregnancy-associated plasma protein A (PAPP-A) has prognostic impact in pregnancy and acute coronary syndrome. Patients with chronic kidney disease have an excessive cardiovascular risk. In an effort to identify novel risk factors for cardiovascular disease, we investigated the relationship of PAPP-A with specific outcomes in diabetic patients undergoing dialysis.

METHODS

PAPP-A was measured in 1098 diabetic hemodialysis patients, who participated in the German Diabetes and Dialysis Study and followed-up for a median of 4 years. By Cox regression analysis, we assessed the association of baseline levels of PAPP-A with all-cause mortality, combined cardiovascular events and the specific outcomes of sudden death, stroke, myocardial infarction and infectious mortality.

RESULTS

Patients had a mean age of 66 ± 8 years (54% male) and median PAPP-A concentration of 17 mIU/L (IQR 13.4-20.9 mIU/L). Per standard deviation increase in PAPP-A the adjusted risk of sudden cardiac death increased by 23% (HR 1.23, 95%CI 1.12-1.36). Categorical analyses showed that the patients in the 4(th) PAPP-A quartile had an adjusted 2.6 fold increased risk of sudden death and 2.8 fold increased risk of stroke as compared to the patients in the 1st quartile. Similarly, the risk of combined cardiovascular events was significantly elevated by the factor 1.5 in patients of the 4(th) quartile. Additionally, PAPP-A levels were associated with infectious deaths and all-cause mortality.

CONCLUSIONS

PAPP-A is associated with sudden death, stroke and infectious complications in diabetic dialysis patients. PAPP-A may be useful for risk assessment and monitoring in populations at high risk of cardiovascular events.

Placental growth factor, pregnancy-associated plasma protein-A, soluble receptor for advanced glycation end products, extracellular newly identified receptor for receptor for advanced glycation end products binding protein and high mobility group box 1 levels in patients with acute kidney injury: a cross sectional study

BACKGROUND

Placental growth factor (PlGF), pregnancy-associated plasma protein-A (PAPP-A), soluble receptor for advanced glycation end products (sRAGE), extracellular newly identified receptor for RAGE binding protein (EN-RAGE) and high mobility group box 1 (HMGB-1) are novel biomarkers in chronic kidney disease (CKD). However, their clinical significance in acute kidney injury (AKI) is unknown. The aim of this cross-sectional study was to determine whether selected biomarkers are changed in AKI patients.

METHODS

Serum PlGF, PAPP-A, sRAGE, EN-RAGE and HMGB-1 levels were assessed in 40 patients with AKI, 42 CKD 5 patients, 31 haemodialysis patients (HD) and 39 age-matched healthy controls.

RESULTS

PAPP-A was elevated in AKI (20.6 ± 16.9 mIU/L) compared with controls (9.1 ± 2.3 mIU/L, p < 0.001). PlGF was not increased in AKI (11.7 ± 7.4 pg/mL) versus controls (8.5 ± 2.4 pg/mL, n.s.), as well as sRAGE was not elevated in AKI (2400 ± 1400 pg/mL) compared with controls (1760 ± 730 pg/mL, n.s), but was lower compared with CKD 5 (3200 ± 1500 pg/mL, p < 0.05); EN-RAGE was elevated in AKI 480 ± 450 ng/mL in comparison with controls (60 ± 62 ng/mL), CKD 5 (190 ± 120 ng/mL), and HD (120 ± 100 ng/mL), all p < 0.001. Similarly, HMGB-1 was increased in AKI (5.8 ± 7.5 ng/mL) versus controls (1.7 ± 1.4 ng/mL), CKD 5 (3.2 ± 3.1 ng/mL) and HD (2.5 ± 2.1 ng/mL), all p < 0.001.In AKI group, in multivariate regression analysis: PAPP-A levels were associated with transferrin (p <0.001), negatively with albumin (p < 0.01) and prealbumin (p < 0.05); PlGF levels were associated with C--reactive protein (p < 0.001). EN-RAGE levels were associated with ferritin (p < 0.01) and orosomucoid (p = 0.02), and HMGB-1 levels with leukocyte count (p < 0.01) and negatively with proteinuria (p = 0.02).

CONCLUSIONS

In AKI patients, PAPP-A, EN-RAGE and HMGB1 are elevated, but sRAGE and PlGF are not increased. Whereas PAPP-A correlates with markers of nutrition; PlGF, EN-RAGE and HMGB-1 are related to inflammatory parameters.

Predictive biomarkers of renal allograft failure

BACKGROUND

Survival of renal allografts is limited by chronic allograft deterioration resulting from processes that are difficult to detect in their early stages, when therapeutic interventions would be most effective. Predictive biomarkers from easily accessible specimens, such as blood or urine, might improve early diagnosis of smoldering graft-damaging processes and help with the identification of patients at particularly high risk of sustained injury, thereby helping to tailor therapy and appropriate follow-up screening.

OBJECTIVE

This article reviews recently investigated biomarkers for the prediction of renal allograft failure, outlines the new '-omic' technologies as a potential source for the identification of new predictive biomarkers and judges the practical value of predictive biomarkers at the present timepoint.

METHODS

A literature search was performed using the medical database PubMed. No general restrictions (e.g., year of publication) were applied, but the focus was set on more recently published articles.

CONCLUSION

Despite a large number of interesting studies, none of the investigated candidate biomarkers is robustly established for widespread clinical use or able to replace biopsies for graft assessment.

PAPP-A in cardiac and non-cardiac conditions

Pregnancy-associated plasma protein-A (PAPP-A), a newly discovered member of insulin like growth factors (IGFs) axis, has been reported to be a biomarker in both cardiac and non-cardiac conditions. PAPP-A mainly acts as a protease cleaving IGF inhibitors - IGF binding proteins (IGFBPs), thereby setting free IGFs. In cardiac conditions, PAPP-A plays an important role in progressive atherosclerosis. As a biomarker, PAPP-A is not only sensitive, specific and early for diagnosis of acute coronary syndrome, but also an independent risk factor for all-cause mortality or combined cardiovascular events. In non-cardiac conditions, PAPP-A is a new anti-aging target. PAPP-A knock out (KO) mice have a prolonged lifespan than the wild type. In addition, PAPP-A is also a biomarker associated with malignant cancer and end stage renal disease.

Pregnancy-associated plasma protein A as an independent mortality predictor in long-term hemodialysis patients

BACKGROUND/AIMS

Pregnancy-associated plasma protein A (PAPP-A) is a biomarker related to vascular damage. The aim of the study was to focus on PAPP-A and related parameters and their relationship to the prognosis of long-term hemodialysis (HD) patients.

METHODS

This is a prospective observational cohort study which included 261 long-term HD patients followed up for 5 years and 66 healthy subjects. PAPP-A, placental growth factor (PlGF), matrix metalloproteinase 2 and 9 (MMP-2, MMP-9), insulin-like growth factor 1 (IGF-1), insulin-like growth factor binding protein-4 (IGFBP-4), and cardiac, nutritional and inflammatory parameters were measured at the beginning of the study and tested as predictors of mortality.

RESULTS

PAPP-A, PlGF, IGF-1, IGFBP-4 and MMP-2 were significantly increased in HD patients compared to controls (PAPP-A 27.6 ± 15.5 mIU/l in HD vs. 9.4 ± 2.5 mIU/l in controls, p < 0.001). Increased PAPP-A was a significant independent predictor of overall mortality and mortality due to infection in the multivariate Cox analysis [HR (95% CI): 1.237 (1.060-1.444), p = 0.007, and 1.416 (1.115-1.798), p = 0.004, per standard deviation, respectively]. PAPP-A was not related to cardiovascular mortality.

CONCLUSION

Increased PAPP-A is a significant independent predictor of overall mortality and mortality due to infection but it was not related to cardiovascular mortality in this study.

Association of pregnancy-associated plasma protein A polymorphism with preeclampsia - a pilot study

OBJECTIVES

The aim of the study was to investigate genetic and biochemical background of PAPP-A (pregnancy-associated plasma protein A) in patients with risk pregnancies.

DESIGN AND METHODS

Five PAPP-A gene polymorphisms and PAPP-A maternal serum levels were studied together in 165 women in third trimester pregnancies complicated with threatening preterm labor (n=98), preeclampsia (n=35), intrauterine growth restriction (n=34) and ICP (intrahepatic cholestasis of pregnancy) (n=15). 114 healthy pregnant women served as controls.

RESULTS

Preeclamptic patients had significantly higher frequency of TT genotype of Cys327Cys polymorphism compared to controls (p<0.01). Patients with ICP had increased serum levels of PAPP-A compared to controls and correlation analysis showed significant relationship between PAPP-A and CRP (C-reactive protein) in the patients with intrauterine growth restriction (r=0.49, p=0.007).

CONCLUSION

Our study indicates the association of TT genotype of Cys327Cys polymorphism of the PAPP-A gene with preeclampsia. However, further study with larger groups of preeclamptic patients is needed to confirm our results.

Posttransplant inflammation associated with onset of chronic kidney disease

BACKGROUND

Chronic allograft nephropathy (CAN), a major complication in renal transplant patients, is an important cause of graft loss. Inflammation as measured in the pretransplant and posttransplant phases, using various markers, has been associated with worse renal function and a greater risk of cardiovascular disease and of long-term graft loss.

OBJECTIVE

The objective of our study was to evaluate whether worsening inflammation in the first 3 months postoperatively was a risk factor for developing CAN.

PATIENTS AND METHODS

We performed a cross-sectional study in 207 patients. The following markers of inflammation (MIF) were determined pretransplant and at 3 months after grafting: C-reactive protein (CRP) (mg/L), interleukin (IL)-6 (pg/mL), IL-10 (pg/mL), tumor necrosis factor (TNF)-α (pg/mL), and its soluble receptor (ng/mL), soluble-IL2R (UI/mL), pregnancy-associated plasma protein A (PAPP-A; mUI/L), and IL-4 (pg/mL). We also calculated the ratio at 3 months versus the pre value of MIF.

RESULTS

CAN was diagnosed after the first year in 23 patients (11.3%) always by renal biopsy performed for clinical indications. Patients with CAN showed worse inflammation, eg, MIF ratios over one, with statistically significant differences for the ratios of TNF-α and PAPP-A (P=.032 and P=.051 respectively). Upon multivariate logistic regression analysis, using CAN as the dependent variable and age, sex, donor age, months on dialysis, acute tubular necrosis, acute rejection, and MIF ratios as covariates, we observed that an acute rejection episode (OR=13.03; CI=2.8-60.9; P=.001), CRP ratio (OR=1.36; CI=1.07-1.73; P=.013), and PAPP-A ratio (OR=1.80; CI=0.92-3.53; P=.005) were independent markers of CAN.

CONCLUSIONS

Among other factors, inflammation may determine the onset of CAN as diagnosed by renal biopsy.

Inflammation, metalloproteinases, and growth factors in the development of carotid atherosclerosis in renal transplant patients

BACKGROUND

Cardiovascular disease is the leading cause of death in renal transplant (RT) patients. Both traditional and emerging risk factors, some of which are controversial, have been described in the pathogenesis of cardiovascular disease. Carotid ultrasound (CUS) is considered to be an excellent diagnostic tool for subclinical atherosclerosis.

OBJECTIVE

To evaluate the relationship between biomarkers of inflammation, growth factors, metalloproteinases, and the development of subclinical atherosclerosis diagnosed by using CUS.

METHODS

We studied 93 RT patients (aged 54±12 years; 67.9% men; 13.5% with pre-RT diabetes mellitus). The following biomarkers were determined in the patients' blood hours before RT: C-reactive protein (CRP) and serum amyloid A using nephelometry; interleukin (IL) 2, 6, 8, and 10 and soluble IL-2 receptor, tumor necrosis factor (TNF) α, vascular endothelial growth factor (VEGF), epidermal growth factor, and monocyte chemotactic peptide using chemoluminescence; and pregnancy-associated plasma protein (PAPP)A using ELISA. A CUS was carried out during the first month after RT.

RESULTS

Carotid intima-media thickness (IMT) was elevated in 51% of the patients, and 50.5% of the patients had atherosclerotic plaque. Both plaque (P=.004) and IMT (P=.001) correlated with age, and the increase of IMT was progressive, on both the left and the right side. Pre-RT CRP, IL-8, TNF-α, VEGF, MCP-1, and PAPP-A were significantly more elevated in patients with plaque. In the multivariate analysis adjusted for clinical variables, age (odds ratio [OR], 1.05; 95% confidence interval [CI], 1.01-1.10; P=.04), CRP (OR, 7.5; 95% CI, 2.05-27.3; P=.002), IL-8 (OR, 4.73; 95% CI, 1.27-17.6; P=.02), and PAPP-A (OR, 4.45; 95% CI, 1.22-16.2; P=.023) were independent markers of the presence of plaque.

CONCLUSIONS

Age, CRP, IL-8, and PAPP-A, and not growth factors, are markers of carotid atheromatous plaque in RT patients.

Recommendations for the assessment and reporting of multivariable logistic regression in transplantation literature

Multivariable logistic regression is an important method to evaluate risk factors and prognosis in solid organ transplant literature. We aimed to assess the quality of this method in six major transplantation journals. Eleven analytical criteria and four documentation criteria were analyzed for each selected article that used logistic regression. A total of 106 studies (6%) out of 1,701 original articles used logistic regression analyses from January 1, 2005 to January 1, 2006. The analytical criteria and their respective reporting percentage among the six journals were: Linearity (25%); Beta coefficient (48%); Interaction tests (19%); Main estimates (98%); Ovefitting prevention (84%); Goodness-of-fit (3.8%); Multicolinearity (4.7%); Internal validation (3.8%); External validation (8.5%). The documentation criteria were reported as follows: Selection of independent variables (73%); Coding of variables (9%); Fitting procedures (49%); Statistical program (65%). No significant differences were found among different journals or between general versus subspecialty journals with respect to reporting quality. We found that the report of logistic regression is unsatisfactory in transplantation journals. Because our findings may have major consequences for the care of transplant patients and for the design of transplant clinical trials, we recommend a practical solution for the use and reporting of logistic regression in transplantation journals.

Intravenous administration of low molecular weight and unfractionated heparin elicits a rapid increase in serum pregnancy-associated plasma protein A

BACKGROUND

Pregnancy-associated plasma protein A (PAPP-A) has been suggested as a useful diagnostic and prognostic marker in acute coronary syndromes. Because low molecular weight heparin (LMWH) and unfractionated heparin (UFH) are commonly used in these cases, we analyzed the effects of intravenous administration of these heparins on serum PAPP-A concentrations.

METHODS

Serum concentrations of total and free PAPP-A were analyzed in 14 patients on chronic hemodialysis and in 10 coronary angiography patients. Ten of the dialysis patients received standard LMWH anticoagulation at the start of dialysis, and 4 were treated with a heparin-free method. Two of the patients on heparin-free hemodialysis received a reduced LMWH bolus 2 h after the start of dialysis. All angiography patients received UFH at the start of the procedure, and 1 patient received 2 extra boluses of UFH. Serum PAPP-A concentrations were analyzed before and during the dialysis session and during the coronary angiography examination.

RESULTS

A rapid increase in total PAPP-A (median, 25-fold) was seen in all patients within 5 min of administration for both LMWH and UFH boluses. This response was due to an increase in free PAPP-A in the serum. PAPP-A did not increase significantly in the patients who underwent heparin-free hemodialysis. Repeated heparin boluses induced a new PAPP-A release. In vitro addition of heparins to samples of whole blood did not increase PAPP-A concentrations.

CONCLUSIONS

Intravenous administration of heparin induces an intense and rapid increase in free PAPP-A in the serum. We recommend that this effect be considered when PAPP-A is assessed as a biomarker in acute coronary syndromes.

Pregnancy-associated plasma protein-A (PAPP-A) and cardiovascular risk

The search for markers to improve risk prediction for individuals at risk of developing serious cardiovascular events is ongoing. New markers of coronary artery disease progression have been identified in recent years, among which, circulating levels of pregnancy-associated plasma protein-A (PAPP-A) offer an interesting profile. PAPP-A may play a role in the development of atherosclerotic lesions and represent also a marker of atheromatous plaque instability and extent of cardiovascular disease. PAPP-A has been shown to be a marker of adverse outcome in both acute coronary syndrome and stable coronary disease patients. The present article reviews currently available evidence supporting a role for PAPP-A as a marker of cardiovascular risk and discusses some of the pitfalls that may limit its use in clinical practice.

Does pregnancy-associated plasma protein A have a role in allergic rhinitis?

BACKGROUND

Pregnancy-associated plasma protein A (PAPP-A), also known as insulin-like growth factor binding protein 4 protease, is postulated to be a new inflammatory marker in various clinical situations such as cardiovascular events, dialysis, renal transplantation, and asthma. PAPP-A also is produced in high concentrations by trophoblasts during pregnancy.

METHODS

We evaluated PAPP-A levels in allergic rhinitis patients and compared these with levels in healthy subjects. Thirty-one newly diagnosed allergic rhinitis patients and 29 healthy controls were included in the study. Serum PAPP-A, IgE, urea, creatinine, aspartate aminotransferase, creatine kinase (CK), CK-MB isoenzyme, total cholesterol, and triglyceride levels were determined.

RESULTS

The serum PAPP-A level was significantly higher (p = 0.013) in the allergic rhinitis group (6.1 +/- 2.9 mU/L) than in the control group (4.5 +/- 1.7 mU/L). The PAPP-A level in patients with allergic rhinitis and asthma (6.1 +/- 2.3 mU/L) was not significantly different (p = 0.959) from that in patients with allergic rhinitis alone (6.1 +/- 3.3 mU/L). The serum PAPP-A level in allergic rhinitis patients who had turbinate hypertrophy (6.9 +/- 2.2 mU/L) had a tendency to be higher than that in patients who had no turbinate hypertrophy (5.5 +/- 3.2 mU/L); however, this difference was not statistically significant (p = 0.151).

CONCLUSION

Increased PAPP-A activity may be involved in the inflammation and tissue remodelling that occurs in allergic rhinitis.

Pregnancy-associated plasma protein A in a large cohort of Type 1 diabetic patients with and without diabetic nephropathy-a prospective follow--up study

AIM

Pregnancy-associated plasma protein A (PAPP-A) has been implicated in the aetiology of acute coronary syndromes and carotid and peripheral artherosclerosis. Diabetic nephropathy is characterized by increased cardiovascular risk. We investigated the prognostic value of PAPP-A in a large cohort of Type 1 diabetic patients.

METHODS

In a prospective observational follow-up study, 197 Type 1 diabetic patients with diabetic nephropathy and a matched group of 178 patients with normoalbuminuria were followed for 10.1 (0-10.3) years. PAPP-A was determined at baseline.

RESULTS

In patients with diabetic nephropathy, plasma PAPP-A was elevated 3.6 (0.4-51.1) mIU/l [median (range)] vs. 2.1 (0.4-46.6) mIU/l in normoalbuminuric patients, P < 0.0001. For acute coronary syndromes, a PAPP-A threshold of 10 mIU/l has been suggested. Thirty-seven patients were above the threshold and of these 13 patients (35%) died, compared with 60 of 338 patients (18%) below the threshold; log rank test P = 0.007. PAPP-A significantly predicted mortality after adjustment for presence of nephropathy; hazard ratio for dying when PAPP-A was above the threshold 2.1 (95% CI 1.13-3.9); P = 0.019. After adjusting for traditional risk factors, the results were attenuated. When only patients with nephropathy were analysed, PAPP-A was significantly predictive of all-cause mortality [P = 0.008; 2.43 (1.26-4.67)] in unadjusted analysis. After adjustment, the predictive value of PAPP-A for all-cause mortality was attenuated (P = 0.064).

CONCLUSION

We find PAPP-A to be associated with increased mortality in Type 1 diabetic patients with nephropathy in unadjusted analysis. After adjustment for traditional risk factors, the prognostic value of PAPP-A was no longer significant.

Obesity, adiponectin and inflammation as predictors of new-onset diabetes mellitus after kidney transplantation

The high incidence of new-onset diabetes mellitus after transplantation (NODAT) suggests the need to find new factors to explain the pathogenesis. Our objectives were (1) to confirm that low levels of pre-transplant adiponectin are an independent risk factor for the development of NODAT in a larger transplanted population; (2) to analyze whether adiponectin is a better predictor of NODAT than other inflammatory markers (C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-alpha) and pregnancy-associated plasma protein A (PAPP-A)) and (3) to assess the relationship between obesity, inflammatory markers and NODAT. One hundred ninety-nine non-diabetic patients (128 men; age: 53 +/- 11 years; body mass index (BMI) 24.98 +/- 3.76 kg/m2) were included. Pre-transplant plasma glucose, insulin, adiponectin, CRP, TNF-alpha, IL-6 and PAPP-A were measured. Forty-five patients developed NODAT. Patients with NODAT had a greater BMI (p = 0.005). Adiponectin was lower (p < 0.001) and CRP higher (p = 0.032) in patients with NODAT. Multivariate logistic regression and Cox analysis showed that the calcineurin inhibitor used, pre-transplant BMI and adiponectin were predictors of NODAT. ROC analysis showed that an adiponectin concentration of 11.4 microg/mL had a significant negative prediction for NODAT risk (sensitivity: 81% and specificity: 70%). Of the inflammatory markers studied, adiponectin proved to be an independent predictor of NODAT.

Pregnancy-associated plasma protein a and soluble receptor for advanced glycation end products after kidney transplantation

BACKGROUND

Pregnancy-associated plasma protein A (PAPP-A) and soluble receptor for advanced glycation end products (sRAGE) are new markers related to vascular damage.

METHODS

Thirty-one patients who had undergone kidney transplantation (TX) in the year 2005 under tacrolimus-based immunosuppression were included in this prospective single-center study. PAPP-A and sRAGE were determined before TX and 2 and 6 weeks and 3 months after TX. The results were correlated with the 3-month protocol kidney graft biopsy findings.

RESULTS

Both PAPP-A and sRAGE decreased after TX (mean values in serum: PAPP-A 20.8, 13.7, 12.1, and 10.7 mIU/l, respectively, before and 2 and 6 weeks and 3 months after TX, p < 0.001; sRAGE 4,403.4, 2,512.7, 1,909.0, and 1,817.6 pg/ml, respectively, before and 2 and 6 weeks and 3 months after TX, p < 0.001) and were correlated with the graft function (PAPP-A vs. modification of diet in renal disease formula r = -0.52, p < 0.001; sRAGE vs. modification of diet in renal disease formula r = -0.54, p < 0.001). Additionally, the PAPP-A levels correlated with interstitial inflammation (r = 0.57, p < 0.05) and vascular intimal thickening (r = 0.47, p < 0.05), while sRAGE correlated with arteriolar hyalinosis (r = 0.49, p < 0.05).

CONCLUSIONS

Our study demonstrates the role of the kidney in the metabolism and/or the removal of PAPP-A and sRAGE. After successful TX, these substances decrease, and, on the contrary, early chronic vascular changes in the kidney TX are associated with elevation of their serum levels.

Pregnancy-associated plasma protein A in dialysis patients

BACKGROUND

Pregnancy-associated plasma protein A (PAPP-A) was recently described as a new marker of cardiovascular events and of inflammation in uremic patients. The aim of this study was to determine levels of PAPP-A in chronic dialysis patients and its possible relationships with renal osteodystrophy.

METHODS

A total of 99 adult chronic hemodialysis patients, 14 peritoneal dialysis patients and 41 control subjects were included in the study. Serum PAPP-A, intact parathormone (iPTH), calcium, phosphorus and alkaline phosphatase (ALP) were measured. The correlations between PAPP-A and iPTH, calcium, phosphorus and ALP were determined.

RESULTS

PAPP-A levels were significantly higher in peritoneal dialysis [4.5 (3.2-6.7) mU/L, median (interquartile range)], and hemodialysis patients [4.7 (3.8-6.5) mU/L] in comparison to control subjects [3.4 (3.0-5.0) mU/L] (p<0.05). In hemodialysis patients, post-dialysis PAPP-A levels [6.2 (4.7-9.4) mU/L] were significantly higher than pre-dialysis levels [4.7 (3.8-6.5) mU/L] (p<0.05). There was a weak but statistically significant positive correlation between serum PAPP-A and iPTH (r=0.216; p=0.041) and ALP (r=0.205; p=0.044) in the hemodialysis group. Correlation between the duration of dialysis therapy and PAPP-A levels was also significant (r=0.267; p=0.008) in the hemodialysis group.

CONCLUSIONS

PAPP-A levels are elevated in acute coronary syndromes and are closely related to inflammation and oxidative stress. We conclude that PAPP-A levels are increased in dialysis patients and may reflect a greater degree of chronic inflammation than osteodystrophy in uremic patients.

Cardiovascular Biomarkers in CKD: Pathophysiology and Implications for Clinical Management of Cardiac Disease

Cardiovascular disease (CVD) is a major cause of morbidity and mortality in patients with all forms of chronic kidney disease (CKD). The underlying pathological state is caused by a complex interplay of traditional and nontraditional risk factors that results in atherosclerosis, arteriosclerosis, and altered cardiac morphological characteristics. This multifactorial disease introduces new challenges in predicting and treating patients with CVD sufficiently early in the course of CKD to positively alter patient outcome. Asymptomatic individuals with progressive CVD are a group of patients that deserve focused attention because early detection and intervention may provide the best opportunity for improved outcome. However, identifying CVD in asymptomatic patients with CKD or end-stage renal disease remains a significant hurdle in the management of these patients. Recently, a number of cardiovascular biomarkers were identified as predictors of patient outcome in individuals with CVD and, with additional research, may be used to guide the early diagnosis of and therapy for CVD in patients with CKD. This review examines the pathophysiological characteristics and potential clinical role of these novel cardiovascular biomarkers in risk stratification, risk monitoring, and selection of preventive therapies for patients with CKD.