Cardiovascular disease in the kidney transplant recipient: epidemiology, diagnosis and management strategies

Triglyceride-Glucose Index and Cardiovascular Events in Kidney Transplant Recipients

Introduction

Kidney transplant recipients (KTRs) have an increased risk of cardiovascular (CV) events (CVEs) compared with the general population. The impact of insulin resistance on CV risk after transplantation is not well defined.

Methods

We tested whether triglyceride-glucose (TyG) index, a surrogate marker of insulin resistance, may predict posttransplant CVEs in a cohort of 715 consecutive KTRs all included 1 year after transplant.

Results

Follow-up was 9.1 ± 4.6 years. Mean TyG at inclusion was 4.75 ± 0.29 (median, 4.73 [4.14-5.84]). In multiple regression analysis, having a TyG above the median value was associated with higher body mass index (BMI), low high-density lipoprotein (HDL) cholesterol level, and greater urinary protein excretion. A total of 127 CVEs (17.7%) occurred during the study period. In univariate analysis, TyG was strongly associated with CVE occurrence (hazard ratio [HR] 2.06, 95% CI 1.42-3.50, for each increase of 0.1 in TyG, P < 0.001). The best predictive value was 4.87 (HR 6.32, 95% CI 3.30-12.11, P < 0.001). The risk of CVE gradually increased with higher TyG index (quartile 2, HR 1.71, 95% CI 0.84-5.20, P = 0.139; quartile 3, HR 3.12, 95% CI 1.61-6.02, P < 0.001; quartile 4, HR 7.46, 95% CI 4.03-13.80, P < 0.001, vs. quartile 1). TyG remained associated with CVE in multivariate analysis (HR 2.11, 95% CI 1.22-3.68, for each increase of 0.1 in TyG, P < 0.001).

Conclusion

Insulin resistance, as measured by the TyG index is strongly associated with CVE in KTRs. Improving insulin sensitivity seems to be a major issue to prevent CV morbidity and mortality in this high-risk population.

The Diagnostic Yield and Clinical Impact of Systematic Screening of Kidney Transplant Candidates by Cardiac Computed Tomography: A Cohort Study

BACKGROUND

Although cardiovascular screening of kidney transplant candidates is recommended, the optimal approach is debated. Previous studies show that noninvasive imaging provides prognostic information, but systematic screening may have less recognized effects, such as additional investigations, incidental findings, procedural complications, and delay of transplantation. To address this, we characterized the diagnostic yield and clinical implications of systematic screening for cardiovascular disease using cardiac computed tomography (CT) in potential kidney transplant candidates.

METHODS

This was a single-center, observational cohort study including all potential kidney transplant candidates >40 years of age or with diabetes or on dialysis treatment for >5 years, systematically referred to cardiac computed tomography (CT; non-contrast CT and coronary CT angiography) between 2014 and 2019 before evaluation for kidney transplantation at Aarhus University Hospital. Patient records were examined for data on baseline characteristics, additional investigations and complications, plasma creatinine, dialysis initiation, time until wait-listing, and incidental findings.

RESULTS

Of 473 patients who underwent cardiac CT, additional cardiac investigations were performed in 156 (33%), and 32 (7%) were revascularized. Twenty-two patients had significant incidental nonvascular findings on cardiac CT. No patient was rejected for transplantation based on cardiac CT. In patients not yet on dialysis, the slope in the estimated glomerular filtration rate decline did not change significantly after coronary CT angiography.

CONCLUSION

Screening by cardiac CT led to additional cardiac investigations in one-third of patients; only a few patients were revascularized, with unknown benefits in asymptomatic patients. Cardiac CT was safe in this population; however, the clinical consequences of the screening were limited.

Markers of terminally differentiated T-cells as predictors of vascular health in renal transplant recipients and healthy adults

Meta-analyses confirm a link between persistent human cytomegalovirus (HCMV) infections and cardiovascular disease, but the mechanisms are unclear. We assess whether proportions of T-cell populations are reliable predictors of subclinical atherosclerosis and/or reflect the burden of HCMV in healthy adults and renal transplant recipients (RTR). Samples were collected from healthy adults and RTR at baseline (T0) and after 32 (24-40) months (T1). Left carotid intima media thickness (cIMT) and proportions of T-cells expressing CD57, LIR-1 or the TEMRA phenotype increased in healthy adults and RTR. The T-cell populations correlated with levels of HCMV-reactive antibodies. Proportions of CD57+, LIR-1+ and TEMRA CD8+ T-cells correlated with left and right cIMT in healthy adults. Proportions of CD57+ and LIR-1+ CD8+ T-cells at T0 predicted left cIMT at T1 among healthy adults, but these associations disappeared after adjustment for covariates. We link LIR-1+ and CD57+CD8+ T-cells with the progression of cIMT in healthy adults.

MCP1 Inverts the Correlation between FGF23 and Omega 6/3 Ratio: Is It Also True in Renal Transplantation?

During chronic kidney disease (CKD) progression, an increase in fibroblast growth factor (FGF23) is present. In stage 5, a positive correlation between FGF23 and omega-6 (n-6) polyunsaturated fatty acids (PUFAs) emerges. Hypothesizing that the rising positive correlation between monocyte chemoattractant protein 1 (MCP1) and n-6 in stage 4 could be the cause, we previously explored FGF23 and MCP1's roles in dyslipidemia and cardiovascular risk in CKD. In the present paper, we retraced the study evaluating 40 kidney transplant patients (KTx), a cohort where several factors might modify the previous relationships found. An ELISA and gas chromatography assessed the MCP1, FGF23, and PUFA levels. Despite the FGF23 increase (p < 0.0001), low MCP1 levels were found. A decrease in the n-6/n-3 ratio (p = 0.042 CKD stage 4 vs. 5) lowered by the increase in both n-3 αlinolenic (p = 0.012) and docosapentaenoic acid (p = 0.049) was observed. A negative correlation between FGF23 and the n-6/n-3 ratio in CKD stage 4 (r2 -0.3 p = 0.043) and none with MCP1 appeared. According to our findings, different mechanisms in the relationship between FGF23, PUFAs, and MCP1 in CKD and KTx patients might be present, which is possibly related to the immunosuppressive status of the last. Future research will further clarify our hypothesis.

The expanded role of the transplant pharmacist: A 10-year follow-up

The role of the transplant pharmacist is recognized by transplant programs, governmental groups, and professional organizations as an essential part of the transplant multidisciplinary team. This role has evolved drastically over the last decade with the advent of major advances in the science of transplantation and the growth of the field, which necessitate expanded pharmacy services to meet the needs of patients. Data now exist within all realms of the phases of care for a transplant recipient regarding the utility and benefit of a solid organ transplant (SOT) pharmacist. Furthermore, governing bodies now have the opportunity to use Board Certification in Solid Organ Transplant Pharmacotherapy as a mechanism to identify and recognize specialty knowledge and expertise within the field of SOT pharmacotherapy. The purpose of this paper is to provide an overarching review of the current and future state of SOT pharmacy while also identifying major changes to the profession, forthcoming challenges, and expected areas of growth.

Ambient black carbon reaches the kidneys

BACKGROUND

Ultrafine particles, including black carbon (BC), can reach the systemic circulation and therefore may distribute to distant organs upon inhalation. The kidneys may be particularly vulnerable to the adverse effects of BC exposure due to their filtration function.

OBJECTIVES

We hypothesized that BC particles reach the kidneys via the systemic circulation, where the particles may reside in structural components of kidney tissue and impair kidney function.

METHODS

In kidney biopsies from 25 transplant patients, we visualized BC particles using white light generation under femtosecond-pulsed illumination. The presence of urinary kidney injury molecule-1 (KIM-1) and cystatin c (CysC) were evaluated with ELISA. We assessed the association between internal and external exposure matrices and urinary biomarkers using Pearson correlation and linear regression models.

RESULTS

BC particles could be identified in all biopsy samples with a geometric mean (5th, 95th percentile) of 1.80 × 103 (3.65 × 102, 7.50 × 103) particles/mm3 kidney tissue, predominantly observed in the interstitium (100 %) and tubules (80 %), followed by the blood vessels and capillaries (40 %), and the glomerulus (24 %). Independent from covariates and potential confounders, we found that each 10 % higher tissue BC load resulted in 8.24 % (p = 0.03) higher urinary KIM-1. In addition, residential proximity to a major road was inversely associated with urinary CysC (+10 % distance: -4.68 %; p = 0.01) and KIM-1 (+10 % distance: -3.99 %; p < 0.01). Other urinary biomarkers, e.g., the estimated glomerular filtration rate or creatinine clearance showed no significant associations.

DISCUSSION AND CONCLUSION

Our findings that BC particles accumulate near different structural components of the kidney represent a potential mechanism explaining the detrimental effects of particle air pollution exposure on kidney function. Furthermore, urinary KIM-1 and CysC show potential as air pollution-induced kidney injury biomarkers for taking a first step in addressing the adverse effects BC might exert on kidney function.

The Effect of Calcineurin Inhibitors on MMPs Activity in Heart and Their Side Effects-A Review of Literature

This review focuses on the role of metalloproteinases in the pathogenesis of myocardial injury in various disease entities. It reveals how the expression and serum levels of metalloproteinases and their inhibitors change in many disease states. At the same time, the study offers a review of the impact of immunosuppressive treatment on this relationship. Modern immunosuppressive treatment is based mainly on the use of calcineurin inhibitors, including cyclosporine A and tacrolimus. The use of these drugs may carry a number of side effects, specifically to the cardiovascular system. The scale and degree of long-term influence on the organism remains unclear, but a significant risk of complications for transplant recipients who take immunosuppressive drugs as part of their daily treatment is to be expected. Therefore, the knowledge on this subject should be expanded and the negative effects of post-transplant therapy minimized. Immunosuppressive therapy plays an important role in the expression and activation of tissue metalloproteinases and their specific inhibitors, which leads to many tissue changes. The presented study is a collection of research results on the effects of calcineurin inhibitors on the heart, with particular emphasis placed on the participation of MMP-2 and MMP-9. It is also an analysis of the effects of specific heart diseases on myocardial remodeling through inductive or inhibitory effects on matrix metalloproteinases and their inhibitors.

Underutilization of left heart catheterization in kidney transplant patients presenting with non-ST segment elevation myocardial infarction

Background

Cardiovascular disease (CVD) is the leading cause of mortality in kidney transplant (KT) patients. The perceived risk of contrast-induced nephropathy (CIN) may create a reluctance to perform coronary angiography in patients presenting with non-ST segment elevation myocardial infarction (NSTEMI).

Methods

National Inpatient Sample (NIS) Database was used to sample individuals presenting with NSTEMI. Patients were stratified into KT and Non-KT cohorts. Outcomes included left heart catheterization rates, mortality, arrhythmias, acute kidney injury/acute renal failure (AKI/ARF), and extended length of hospital stay (ELOS) (>72 h). Propensity matching (1:1 ratio) and regression analyses were performed.

Results

Out of 336,354 patients with NSTEMI, 742 patients were in the KT group. KT patients were less likely to have LHC relative to non-KT patients (22.0 % vs 18.3 %); a difference that persisted on post-match analysis (27.1 % vs 19.4 %). On pre-match analysis, KT transplant patients that underwent LHC had lower mortality (10.3 % vs 0.7 %), AKI/ARF (44.6 % vs 27.9 %), arrhythmias (30.4 % vs 20.6 %) and lower ELOS (58.6 % vs 41.9 %). Post-match, KT cohort patient that underwent LHC had lower arrhythmias (OR:0.60[0.38-0.96]), AKI/ARF (OR = 0.51[0.34-0.77]), ELOS (OR:0.49[0.34-0.73]).

Conclusion

KT patients underwent LHC much less frequently than their non-KT counterparts for NSTEMI. Coronary angiography and subsequent revascularization were associated with a significant decrease in morbidity and mortality. This theorized risk of CIN should not outweigh the benefit of LHC in KT patients.

A Retrospective Study on Vitamin D Status and Its Association With Cardiometabolic Risk Factors Among Children With Chronic Kidney Disease at King Abdulaziz University Hospital

BACKGROUND

Vitamin D deficiency is a significant global health issue. It is prevalent in chronic kidney disease (CKD) patients, which is an important cause of death among children. Many studies have found a link between low vitamin D status in CKD patients and cardiovascular disease (CVD) risk factors. However, there are no data on this relationship in children with CKD in Saudi Arabia.

AIMS

We aimed to demonstrate this association among children with CKD admitted to the King Abdulaziz University Hospital (KAUH) in Jeddah, Saudi Arabia.

MATERIALS AND METHODS

Data were collected between June and August 2020 from a convenience sample of pediatric patients.

RESULTS

In total, 153 pediatric patients with CKD stages 2-5 were admitted to the KAUH between 2010 and 2019, and 67.3% had CKD stage 5. Approximately 4.6% and 10.5% of the participants were overweight or obese, respectively. Patients who fell into the lower 25-hydroxyvitamin D (25[OH]D) tertile were older, had higher body mass index (BMI) values, and had higher blood pressure than those in the upper two tertiles; however, these differences were not statistically significant. There was a significant inverse association of 25(OH)D levels with BMI, blood pressure, and serum creatinine levels.

CONCLUSIONS

The results of this retrospective study suggest that patients with CKD and lower vitamin D levels have a higher BMI and blood pressure and are therefore at higher risk of developing CVD. Future prospective studies with a larger sample size are needed to confirm these findings. Randomized clinical trials are also needed to investigate the effect of sufficient vitamin D status on reducing CVD in patients with CKD.

Age at Mortality in Patients with Type 2 Diabetes Who Underwent Kidney Transplantation: An Analysis of Data from the Korean National Health Insurance and Statistical Information Service, 2006 to 2018

BACKGROUND

Although the clinical outcomes of diabetes have improved, diabetes remains the principal cause of end-stage renal disease. The aim of the study is to investigate whether mortality trends in individuals with type 2 diabetes and kidney transplantation (KT) have changed.

METHODS

This study analyzed data from the National Health Insurance Service claims database linked to death records from the National Statistical Information Service in Korea. Information from a total of 2521 deaths of KT recipients was collected from 2006 to 2018.

RESULTS

The age at death of KT recipients increased from 57.4 years in 2006 to 65.2 years in 2018, with a mean change of +0.65 years/year (p < 0.001). The overall age at death increased by 0.55 and 0.66 years/year in the type 2 diabetes and non-diabetes populations, respectively. The age at death was significantly higher in the type 2 diabetes group, and was maintained during the study period. The proportion of death due to malignancy and cerebrovascular and heart disease was maintained, that due to type 2 diabetes decreased and that due to pneumonia increased. Neither diabetes nor hypertension determined the age at death, and the age at KT was the most prominent factor affecting age at death in KT recipients.

CONCLUSIONS

The age at death in KT recipients increased over the 12 years between 2006 and 2018, with similar trends in the type 2 diabetes and non-diabetes groups. The age at KT was higher in patients with type 2 diabetes, and was the main contributor to the age at death in KT recipients.

Non-Traditional Non-Immunological Risk Factors for Kidney Allograft Loss-Opinion

Rates of late allograft loss have improved slowly in the last decades. Well described traditional risk factors that influence allograft survival include cardiovascular events, rejection, infections and post-transplant neoplasia. Here, we critically evaluate the influence of several non-immunological, non-traditional risk factors and describe their impact on allograft survival and cardiovascular health of kidney transplant recipients. We assessed the following risk factors: arterial stiffness, persistent arteriovenous access, mineral bone disease, immunosuppressive drugs residual levels variability, hypomagnesemia, glomerular pathological alterations not included in Banff criteria, persistent inflammation and metabolic acidosis.

A Systematic Review and Meta-Analysis of Posttransplant Anemia With Overall Mortality and Cardiovascular Outcomes Among Kidney Transplant Recipients

Introduction: Posttransplant anemia is a common finding after kidney transplantation. A previous meta-analysis reported an association between anemia and graft loss. However, data on cardiovascular outcomes have not yet been reported. Objective: We conducted an updated meta-analysis to examine the association between posttransplant anemia and outcomes after transplantation including cardiovascular mortality in adult kidney transplant recipients. Methods: We comprehensively searched the databases of MEDLINE and EMBASE from inception to November 2021. Data from each study were combined using the random-effects model. Generic inverse variance method of DerSimonian and Laird was employed to calculate the risk ratios and 95% CIs. Results: Seventeen studies from August 2006 to April 2019 were included (16 463 kidney transplantation recipients). Posttransplant anemia was associated with overall mortality (pooled risk ratio = 1.72 [1.39, 2.13], I² = 56%), graft loss (pooled risk ratio = 2.28 [1.77, 2.93], I² = 94%), cardiovascular death (pooled risk ratio = 2.06 [1.35, 3.16], I² = 0%), and cardiovascular events (pooled risk ratio = 1.33 [1.10, 1.61], I² = 0%). Early anemia (≤6 months), compared with late anemia (>6 months), has higher risk of overall mortality and graft loss with a pooled risk ratio of 2.63 (95% CI 1.79-3.86; I² = 0%) and 2.96 (95% CI 2.29-3.82; I² = 0%), respectively. Discussion: In addition to increased risk of graft loss, our updated meta-analysis demonstrated that posttransplant anemia was significantly associated with poor outcomes after kidney transplantation including overall mortality, graft loss, cardiovascular death, and cardiovascular events. Future studies are required to assess the effects of treatment strategies for posttransplant anemia on posttransplant outcomes including cardiovascular mortality.

De novo major cardiovascular events in kidney transplant recipients: a comparative matched cohort study

BACKGROUND

Although cardiovascular disease is known to be one of the leading causes of death after kidney transplantation (KT), evidence on the risk difference of de novo major adverse cardiovascular events (MACEs) in kidney transplant recipients (KTRs) compared with that in dialysis patients or the general population (GP) remains rare.

METHODS

We identified KTRs using the nationwide health insurance database in South Korea and then 1:1 matched them with the dialysis and GP controls without a pre-existing MACE. The primary endpoint was defined as de novo MACEs consisting of myocardial infarction, coronary revascularization and ischemic stroke. The secondary endpoints were all-cause mortality and death-censored graft failure (DCGF) in KTRs.

RESULTS

We included 4156 individuals in each of the three groups and followed them up for 4.7 years. De novo MACEs occurred in 3.7, 21.7 and 2.5 individuals per 1000 person-years in the KTRs, dialysis controls and GP controls, respectively. KTRs showed a lower MACE risk {adjusted hazard ratio (aHR) 0.16 [95% confidence interval (CI) 0.12-0.20], P < .001} than dialysis controls, whereas a similar MACE risk to GP controls [aHR 0.81 (95% CI 0.52-1.27), P = .365]. In addition, KTRs showed a similar MACE risk compared with the GP group, regardless of age, sex and the presence of comorbidities, including hypertension, diabetes and dyslipidemia. Among KTRs, de novo MACEs were associated with an increased risk of all-cause mortality, but not with DCGF.

CONCLUSIONS

De novo MACEs in KTRs were much lower than that in dialysis patients and had a similar risk to the GP, but once it occurred it caused elevated mortality risk in KTRs.

Plasma Copper Concentration Is Associated with Cardiovascular Mortality in Male Kidney Transplant Recipients

Kidney transplant recipients (KTR) are at increased risk of cardiovascular mortality. We investigated whether, in KTR, post-transplantation copper status is associated with the risk of cardiovascular mortality and potential effect modification by sex. In this cohort study, plasma copper was measured using mass spectrometry in extensively-phenotyped KTR with a functioning allograft >1-year. Cox regression analyses with the inclusion of multiplicative interaction terms were performed. In 660 KTR (53 ± 13 years old, 56% male), the median baseline plasma copper was 15.42 (IQR 13.53-17.63) µmol/L. During a median follow-up of 5 years, 141 KTR died, 53 (38%) due to cardiovascular causes. Higher plasma copper was associated with an increased risk of cardiovascular mortality in the overall KTR population (HR 1.37; 95% CI, 1.07-1.77 per 1-SD, p = 0.01). Sex was a significant effect modifier of this association (Pinteraction = 0.01). Among male KTR, higher plasma copper concentration was independently associated with a two-fold higher risk of cardiovascular mortality (HR 2.09; 95% CI, 1.42-3.07 per 1-SD, p < 0.001). Among female KTR, this association was absent. This evidence offers a rationale for considering a sex-specific assessment of copper's role in cardiovascular risk evaluation. Further studies are warranted to elucidate whether copper-targeted interventions may decrease cardiovascular mortality in male KTR.

Risk factors of severe periodontitis in kidney transplant recipients: A case-control study

BACKGROUND

Kidney transplant recipients (KTRs) represent a vulnerable group of patients who develop a number of comorbidities. Severe periodontitis (SP) is associated with the most common chronic systemic diseases including kidney diseases. The objective of this study was to explore the risk factors for SP in KTRs.

METHODS

In this study, KTRs were divided into those with or without periodontitis and in relation to the severity of periodontitis. A comprehensive medical and periodontal examination was performed and evaluated. Multivariate logistic regression was performed to examine possible risk factors for SP among KTRs.

RESULTS

A total of 100 KTRs were included in the analysis, of which 87% had periodontitis. Significant predictors of periodontitis were older age (OR = 1.07, 95% CI [1.01, 1.13], p = 0.016) and lower skeletal muscle mass (OR = 0.88, 95% CI [0.78, 0.99], p = 0.035). When examining periodontitis severity, predictors of SP (n = 21, 24%) were increased levels of uric acid (OR = 1.01, 95% CI [1.00, 1.02], p = 0.022) and dental plaque (OR = 1.04, 95% CI [1.01, 1.07], p = 0.013). In the subset analysis that included only KTRs with measured advanced glycation end products (AGE) (n = 47), 34% (n = 16) had SP. The predictors of SP were AGE (OR = 3.89, 95% CI [1.28, 11.82], p = 0.017) and dental plaque (OR = 1.07, 95% CI [1.01, 1.13], p = 0.028).

CONCLUSIONS

KTRs with SP had significantly higher uric acid levels and AGE, which may contribute to the systemic health status of this patient population.

Range and Consistency of Cardiovascular Outcomes Reported by Clinical Trials in Kidney Transplant Recipients: A Systematic Review

Cardiovascular disease is a major cause of morbidity and mortality in kidney transplant recipients. Trial evidence to improve cardiovascular outcomes is limited by inconsistent reporting of outcomes, which may also lack patient-relevance. This study aimed to assess the range and consistency of cardiovascular outcomes reported by contemporary trials in kidney transplant recipients.

Methods

A systematic review of all randomized controlled trials involving adult kidney transplant recipients that reported at least 1 cardiovascular outcome from January 2012 to December 2019 was performed, including Embase, MEDLINE, Cochrane, and ClinicalTrials.gov electronic databases. Trial characteristics were extracted and all levels of specification of the cardiovascular outcome measures reported were analyzed (the measure definition, metric' and method of aggregation). Measures assessing a similar aspect of cardiovascular disease were categorized into outcomes.

Results

From 93 eligible trials involving 27 609 participants, 490 outcome measures were identified. The outcome measures were grouped into 38 outcomes. A cardiovascular composite was the most common outcome reported (40 trials, 43%) followed by cardiovascular mortality (42%) and acute coronary syndrome (31%). Cardiovascular composite was also the most heterogeneous outcome with 77 measures reported followed by cardiovascular mortality (n = 58) and inflammatory biomarkers (n = 51). The most common cardiovascular composite outcome components reported were major cardiovascular events (18 trials), stroke unspecified (11 trials), and myocardial infarction unspecified (10 trials).

Conclusions

There is substantial heterogeneity in cardiovascular outcome reporting in kidney transplant trials.

Factors associated with cardiovascular events after simultaneous liver-kidney transplant from the US Multicenter Simultaneous Liver-Kidney Transplant Consortium

Cardiovascular disease is a leading complication after both liver and kidney transplantation. Factors associated with and rates of cardiovascular events (CVEs) after simultaneous liver-kidney transplant (SLKT) are unknown. This was a retrospective cohort study of adult SLKT recipients between 2002 and 2017 at six centers in six United Network for Organ Sharing regions in the US Multicenter SLKT Consortium. The primary outcome was a CVE defined as hospitalization due to acute coronary syndrome, arrhythmia, congestive heart failure, or other CV causes (stroke or peripheral vascular disease) within 1 year of SLKT. Among 515 SLKT subjects (mean age ± SD, 55.4 ± 10.6 years; 35.5% women; 68.1% White), 8.7% had a CVE within 1 year of SLKT. The prevalence of a CVE increased from 3.3% in 2002-2008 to 8.9% in 2009-2011 to 14.0% in 2012-2017 ( p  = 0.0005). SLKT recipients with a CVE were older (59.9 vs. 54.9 years, p  < 0.0001) and more likely to have coronary artery disease (CAD) (37.8% vs. 18.4%, p  = 0.002) and atrial fibrillation (AF) (27.7% vs. 7.9%, p  = 0.003) than those without a CVE. There was a trend toward older age by era of SLKT ( p  = 0.054). In multivariate analysis adjusted for cardiac risk factors at transplant, age (odds ratio [OR], 1.06; 95% confidence interval [CI], 1.02, 1.11), CAD (OR, 3.62; 95% CI, 1.60, 8.18), and AF (OR, 2.36; 95% CI, 1.14, 4.89) were associated with a 1-year CVE after SLKT. Conclusion : Among SLKT recipients, we observed a 4-fold increase in the prevalence of 1-year CVEs over time. Increasing age, CAD, and AF were the main potential explanatory factors for this trend independent of other risk factors. These findings suggest that CV risk protocols may need to be tailored to this high-risk population.

Sex-related short-term blood pressure variability differences in kidney transplant recipients

OBJECTIVE

Kidney transplant recipients (KTRs) display higher cardiovascular morbidity and mortality than the general population. Increased short-term blood pressure variability (BPV) is associated with a higher risk of adverse cardiovascular outcomes in chronic kidney disease (CKD). The aim of this study is to investigate sex differences in short-term BPV in KTRs.

METHODS

In total, 136 male and 69 female KTRs with valid 24 h ambulatory blood pressure monitoring were included in this analysis. Systolic and diastolic BPV indices [SD, weighted SD (wSD), coefficient of variation (CV), average real variability (ARV) and variability independent of the mean (VIM)] were calculated with validated formulas for the 24 h, daytime and nighttime periods.

RESULTS

Age, time from transplantation surgery and history of major comorbidities did not differ between men and women. During the 24-h period, systolic BPV indices did not differ between men and women (SBP-ARV: 9.4 ± 2.2 vs. 9.9 ± 2.5; P = 0.212). During the daytime period, SBP-CV and SBP-VIM were significantly higher in females compared with male participants (SBP-CV: 9.9 ± 2.4 vs. 11 ± 3.1%; P = 0.022 and SBP-VIM: 12.6 ± 3.0 vs 14.2 ± 3.9; P = 0.008); daytime SBP-SD and SBP-ARV, and all studied indexes during nighttime did not differ between groups. No significant between-group differences in 24 h and daytime diastolic BPV indices were detected. Nighttime DBP-CV was marginally higher in men (12.0 ± 3.6 vs. 11.4 ± 4.0; P = 0.053); the rest nighttime diastolic BPV indices measured were also nonsignificantly higher in men.

CONCLUSION

In conclusion, 24-h systolic and diastolic BPV parameters did not differ between male and female KTRs, but short-term BPV over the respective day- and nighttime periods showed different trends in men and women. Further studies are needed to examine possible differences in long-term BPV in KTRs.

Interventions Against Posttransplantation Diabetes: A Scientific Rationale for Treatment Hierarchy Based on Literature Review

Posttransplant diabetes (PTD) is a common medical complication after solid organ transplantation. Because of adverse outcomes associated with its development and detrimental impact on long-term survival, strategies to prevent or manage PTD are critically important but remain underresearched. Treatment hierarchies of antidiabetic therapies in the general population are currently being revolutionized based on cardiovascular outcome trials, providing evidence-based rationale for optimization of medical management. However, opportunities for improving medical management of PTD are challenged by 2 important considerations: (1) translating clinical evidence data from the general population to underresearched solid organ transplant cohorts and (2) targeting treatment based on primary underlying PTD pathophysiology. In this article, the aim is to provide an overview of PTD treatment options from a new angle. Rationalized by a consideration of underlying PTD pathophysiological defects, which are heterogeneous among diverse transplant patient cohorts, a critical appraisal of the published literature and summary of current research in progress will be reviewed. The aim is to update transplant professionals regarding medical management of PTD from a new perspective tailored therapeutic intervention based on individualized characteristics. As the gap in clinical evidence between management of PTD versus type 2 diabetes widens, it is imperative for the transplant community to bridge this gap with targeted clinical trials to ensure we optimize outcomes for solid organ transplant recipients who are at risk or develop PTD. This necessary clinical research should help efforts to improve long-term outcomes for solid transplant patients from both a patient and graft survival perspective.

PCSK9 inhibitors in a renal transplant patient complicated with hepatitis B: A case report and literature review

Lipid metabolism disorders are recognized to be one of the most frequent complications of renal transplantation, while dyslipidemia and chronic kidney disease (CKD) are strong risk factors for arteriosclerotic cardiovascular disease (ASCVD). Proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i) are novel lipid-lowering drugs, the safety and efficacy of which are yet to be confirmed in transplanted patients. There have been several small-sample studies using PCSK9i in patients after heart transplantation, while fewer cases use PCSK9i after kidney transplantation. We report a case of a renal transplant recipient complicated with hepatitis B treated with PCSK9i, which achieved a remarkable lipid-lowering efficacy, and no significant adverse effects were found during the follow-up.

Is Exclusion of Coronary Artery Disease in the Kidney Allocation System Preventing Optimal Longevity Matching?

BACKGROUND

Coronary artery disease (CAD) in a kidney transplant candidate is an important predictor of posttransplant mortality. It is not known how the exclusion of CAD in the kidney allocation system has impacted its goal of longevity matching.

METHODS

This is an observational study on adult deceased donor kidney transplant alone recipients between December 4, 2014, and December 31, 2018, with Medicare fee for service (FFS) insurance. Patients were categorized on the basis of Kidney Donor Profile Index (KDPI), Estimated Posttransplant Survival (EPTS), and CAD. Outcomes studied were mortality, death with a functioning graft, overall graft loss, and death-censored graft loss.

RESULTS

Among 21 151 patients with Medicare FFS coverage for >1 y before transplant, there were 2869 and 18 282 patients with and without CAD, respectively. On Kaplan-Meier analysis, there was higher risk of mortality, death with a functioning graft, overall graft loss, and death-censored graft loss with CAD ( P < 0.05 for all). Mortality was higher for CAD group within each category of KDPI and among patients with Estimated Posttransplant Survival 0% to 20% receiving kidneys with KDPI <20% ( P < 0.001 for all). On Cox multivariate analysis, the hazard ratios (HRs) of mortality and graft loss were higher with CAD diagnosis without intervention (HR 1.38 [1.25-1.52] and 1.29 [1.18-1.4]), CAD with stents (HR 2.76 [1.68-4.53] and 2.36 [1.46-3.81]), and CAD with bypass surgery (HR 1.56 [1.29-1.89] and 1.39 [1.17-1.65]). Posttransplant CAD events were higher in patients with preexisting CAD ( P < 0.001).

CONCLUSIONS

The exclusion of a candidate's history of CAD in the kidney allocation system adversely impacts its goal of optimal longevity matching.

A CT-based pelvic calcification score in kidney transplant patients is a possible predictor of graft and overall survival

OBJECTIVES

Computerized tomography (CT) is the most accurate method for evaluating pelvic calcifications, which are of utmost importance for planning kidney transplantation (KT). The aim of our study was to evaluate the incidence and distribution of iliac artery calcifications and correlate the novel pelvic calcification score (PCS) with cardiovascular risk factors and graft and overall survival in KT patients.

METHODS

We retrospectively included 118 KT patients operated at our institution with pretransplant pelvic CT. Calcification morphology, circumference and length of both common and external iliac arteries were independently scored by two uroradiologists. PCS was calculated as the total score sum of all three calcification features in all vessels. PCS correlation with graft and patient survival was performed.

RESULTS

Calcification in at least one vascular segment was found in 79% of patients. PCS was significantly higher in male patients (p = 0.006), patients over 55 years (p < 0.001), and patients on haemodialysis (p = 0.016). Patients with a PCS >3 had significantly shorter graft and overall survival rates (p = 0.041 and p = 0.039, respectively).

CONCLUSIONS

The extent of iliac artery calcification in KT recipients quantified by PCS on pretransplant CT correlates with graft and overall patient survival. A PCS over three was associated with worse clinical outcomes and could become a possible prognostic factor.

ADVANCES IN KNOWLEDGE

Our novel PCS is a robust method for quantifying iliac artery calcification burden. Since higher a PCS correlates with worse patient and graft survival, PCS has the potential to become a prognostic factor in kidney transplant patients.

Cardiovascular Disease Assessment Prior to Kidney Transplantation

Cardiovascular disease is highly prevalent and the leading cause of mortality in patients with chronic kidney disease, end-stage kidney disease, and kidney transplantation. However, kidney transplantation offers improved survival and quality of life, with an overall reduction in cardiovascular disease events; therefore, it remains the optimal treatment choice for those with advanced kidney disease. Pretransplantation cardiovascular assessment is performed prior to wait-listing and at routine intervals with the principal goal of screening for asymptomatic cardiac disease, intervening when necessary to improve long-term patient and allograft survival. Current clinical practice guidelines are based on expert opinion, with a lack of high-quality evidence to guide standardized screening practices. Recent studies support de-escalation in screening with avoidance of preemptive revascularization in asymptomatic patients, but they fail to provide clear guidance on how best to assess the cardiovascular fitness of this high-risk group. Herein we summarize current practice guidelines, discuss key study findings, highlight the role of optimal medical therapy, and evaluate future directions for cardiovascular disease assessment in this population.

Cardiovascular Effects of Home Dialysis Therapies: A Scientific Statement From the American Heart Association

Cardiovascular disease is the leading cause of morbidity and mortality in patients with end-stage kidney disease. Currently, thrice-weekly in-center hemodialysis for 3 to 5 hours per session is the most common therapy worldwide for patients with treated kidney failure. Outcomes with thrice-weekly in-center hemodialysis are poor. Emerging evidence supports the overarching hypothesis that a more physiological approach to administering dialysis therapy, including in the home through home hemodialysis or peritoneal dialysis, may lead to improvement in several cardiovascular risk factors and cardiovascular outcomes compared with thrice-weekly in-center hemodialysis. The Advancing American Kidney Health Initiative, which has a goal of increasing the use of home dialysis, is aligned with the American Heart Association's 2024 mission to champion a full and healthy life and health equity. We conclude that incorporation of interdisciplinary care models to increase the use of home dialysis therapies in an equitable manner will contribute to the ultimate goal of improving outcomes for patients with kidney failure and cardiovascular disease.

Hypertension in kidney transplant recipients

Kidney transplantation is considered the treatment of choice for end-stage kidney disease patients. However, the residual cardiovascular risk remains significantly higher in kidney transplant recipients (KTRs) than in the general population. Hypertension is highly prevalent in KTRs and represents a major modifiable risk factor associated with adverse cardiovascular outcomes and reduced patient and graft survival. Proper definition of hypertension and recognition of special phenotypes and abnormal diurnal blood pressure (BP) patterns is crucial for adequate BP control. Misclassification by office BP is commonly encountered in these patients, and a high proportion of masked and uncontrolled hypertension, as well as of white-coat hypertension, has been revealed in these patients with the use of ambulatory BP monitoring. The pathophysiology of hypertension in KTRs is multifactorial, involving traditional risk factors, factors related to chronic kidney disease and factors related to the transplantation procedure. In the absence of evidence from large-scale randomized controlled trials in this population, BP targets for hypertension management in KTR have been extrapolated from chronic kidney disease populations. The most recent Kidney Disease Improving Global Outcomes 2021 guidelines recommend lowering BP to less than 130/80 mmHg using standardized BP office measurements. Dihydropyridine calcium channel blockers and angiotensin-converting enzyme inhibitors/angiotensin-II receptor blockers have been established as the preferred first-line agents, on the basis of emphasis placed on their favorable outcomes on graft survival. The aim of this review is to provide previous and recent evidence on prevalence, accurate diagnosis, pathophysiology and treatment of hypertension in KTRs.

The prognostic value of pre-operative coronary evaluation in kidney transplanted patients

Aims

Non-invasive coronary assessment using single-photon emission computerized tomography (SPECT) testing for potential cardiac ischemia is an essential part of the evaluation of kidney transplant candidates. We aimed to examine the prognostic value of preoperative SPECT test results in kidney transplanted patients.

Methods and results

We retrospectively analyzed the pre-surgical nuclear SPECT test results in a registry of kidney transplanted patients. Follow-up at 1 month and 1 year recorded major adverse cardiac events (MACE) including non-fatal myocardial infarction, all-cause mortality and hospitalization due to cardiovascular disease following the renal transplantation. Of 577 patients available for analysis, 408 (70.9%) patients underwent nuclear SPECT test pre-transplant and 83 (20.3%) had abnormal results with either evidence of ischemia or infarct. A significantly higher incidence of post-operative MACE at 1 month was evident among patients with abnormal SPECT test compared to patients with no evidence of ischemia (10.8 vs. 4.3% respectively; P = 0.019). Differences were mostly derived from significantly increased rates of myocardial infarction events (8.4 vs. 1.8%; P = 0.002). Yet, MACE rate was not statistically different at 1 year (20.5 vs. 13.1%; P = 0.88). Importantly, the prognostic impact of an abnormal SPECT was significantly attenuated for all outcomes following multivariable adjusting for conventional cardiovascular risk factors and coronary revascularization.

Conclusion

Pre-surgical cardiac risk assessment of kidney transplant candidates with nuclear SPECT test was found to be predictive of post-operative MACE, yet apparently, its prognostic value was significantly attenuated when adjusted for cardiac risk factors.

Cardiovascular Risk after Kidney Transplantation: Causes and Current Approaches to a Relevant Burden

Background. Cardiovascular disease is a frequent complication after kidney transplantation and represents the leading cause of mortality in this population. Material and Methods. We searched for the relevant articles in the National Institutes of Health library of medicine, transplant, cardiologic and nephrological journals. Results. The pathogenesis of cardiovascular disease in kidney transplant is multifactorial. Apart from non-modifiable risk factors, such as age, gender, genetic predisposition and ethnicity, several traditional and non-traditional modifiable risk factors contribute to its development. Traditional factors, such as diabetes, hypertension and dyslipidemia, may be present before and may worsen after transplantation. Immunosuppressants and impaired graft function may strongly influence the exacerbation of these comorbidities. However, in the last years, several studies showed that many other cardiovascular risk factors may be involved in kidney transplantation, including hyperuricemia, inflammation, low klotho and elevated Fibroblast Growth Factor 23 levels, deficient levels of vitamin D, vascular calcifications, anemia and poor physical activity and quality of life. Conclusions. The timely and effective treatment of time-honored and recently discovered modifiable risk factors represent the basis of the prevention of cardiovascular complications in kidney transplantation. Reduction of cardiovascular risk can improve the life expectancy, the quality of life and the allograft function and survival.

Association of Abdominal Arterial Calcification Score with Patients' Survival and Kidney Allograft Function after Kidney Transplant

BACKGROUND

Abdominal arterial calcification (AAC) is common among candidates for kidney transplant. The aim of this study is to correlate AAC score value with post-kidney transplant outcomes.

METHODS

We modified the coronary calcium score by changing the intake data points and used it to quantitate the AAC. We conducted a retrospective clinical study of all adult patients who were transplanted at our center, between 2010 and 2013, and had abdominal computed tomography scan done before transplantation. Outcomes included mortality, pulse pressure (PP) measured by 24 h ambulatory blood pressure monitoring system, and kidney allograft function measured by iothalamate clearance.

RESULTS

For each 1000 increase of AAC score value, there is an associated 1.05 increase in the risk of death (95% CI 1.02, 1.08) (p < 0.001). Overall median AAC value for all patients was 1784; Kaplan-Meier curve showed reduced survival of all-cause mortality for patients with AAC score value above median and reduced survival among patients with cardiac related mortality. The iothalamate clearance was lower among patients with total AAC score value above the median. Patients with abnormal PP (< 40 or > 60 mmHg) had an elevated median AAC score value at 4319.3 (IQR 1210.4, 11097.1) compared to patients with normal PP with AAC score value at 595.9 (IQR 9.9, 2959.9) (p < 0.001).

CONCLUSION

We showed an association of AAC with patients' survival and kidney allograft function after kidney transplant. The AAC score value could be used as a risk stratification when patients are considered for kidney transplant.

Ambulatory blood pressure trajectories and blood pressure variability in kidney transplant recipients: a comparative study against chronic kidney disease patients

Background

Methods

Results

Conclusion

New Approaches to Cardiovascular Disease and Its Management in Kidney Transplant Recipients

Cardiovascular events, including ischemic heart disease, heart failure, and arrhythmia, are common complications after kidney transplantation and continue to be leading causes of graft loss. Kidney transplant recipients have both traditional and transplant-specific risk factors for cardiovascular disease. In the general population, modification of cardiovascular risk factors is the best strategy to reduce cardiovascular events; however, studies evaluating the impact of risk modification strategies on cardiovascular outcomes among kidney transplant recipients are limited. Furthermore, there is only minimal guidance on appropriate cardiovascular screening and monitoring in this unique patient population. This review focuses on the limited scientific evidence that addresses cardiovascular events in kidney transplant recipients. Additionally, we focus on clinical management of specific cardiovascular entities that are more prevalent among kidney transplant recipients (ie, pulmonary hypertension, valvular diseases, diastolic dysfunction) and the use of newer evolving drug classes for treatment of heart failure within this cohort of patients. We note that there are no consensus documents describing optimal diagnostic, monitoring, or management strategies to reduce cardiovascular events after kidney transplantation; however, we outline quality initiatives and research recommendations for the assessment and management of cardiovascular-specific risk factors that could improve outcomes.

Perioperative outcomes and readmissions following cardiac operations in kidney transplant recipients

OBJECTIVE

Although kidney transplant (KTx) recipients are at significant risk for cardiovascular disease, outcomes following cardiac operations have been examined in limited series. The present study thus aimed to assess the impact of KTx on in-hospital perioperative outcomes and readmissions in a nationally representative cohort.

METHODS

All adults undergoing elective coronary artery bypass grafting, valve repair/replacement or a combination thereof were identified from the 2010-2018 Nationwide Readmissions Database. Patients were stratified by history of KTx. Transplant-capable centres were defined as hospitals performing at least one KTx annually. To perform risk-adjustment in assessing outcomes, multivariable regression models were developed.

RESULTS

Of an estimated 1 407 351 patients included for analysis, 0.2% (n=2849) were KTx recipients. Compared with the general cardiac surgical population, patients with prior KTx experienced higher adjusted odds of in-hospital mortality (adjusted OR (AOR) 2.44, 95% CI 1.72 to 3.47, p<0.001) and perioperative complication (AOR 1.67, 95% CI 1.44 to 1.94, p<0.001). Additionally, KTx was independently associated with greater readmission rates within 30 days (AOR 1.96, 95% CI 1.65 to 2.34, p<0.001) with kidney injury contributing significantly to the burden of rehospitalisation (4.6 vs 1.8%, p=0.005). In a subpopulation comprised of only KTx recipients, treatment at a transplant-capable centre reduced odds of kidney injury with non-transplant hospitals as reference (AOR 0.65, 95% CI 0.43 to 0.98, p=0.037).

CONCLUSIONS

Kidney transplant recipients undergoing cardiac operations encounter significant risks compared with the general surgical population. Referral to transplant-capable centres should be explored to improve outcomes and to preserve allograft function in this population.

Protocol for the IMPACT Trial: Improving Healthcare Outcomes in American Transplant Recipients Using Culturally-Tailored Novel Technology

Kidney transplant (KT) recipients face post-transplant health issues. Immunosuppressive agents can cause hyperlipidemia, hypertension, post-transplant diabetes, and glomerulopathy. Post-transplant weight gain and decreased activity are associated with poor quality of life, sleep, and cardiometabolic outcomes. This study will test the feasibility and acceptability of a culturally tailored diet and exercise intervention for KT patients delivered immediately post-transplant using novel technology. A registered dietitian nutritionist (RDN) and physical rehabilitation therapist will examine participants' cultural background, preferences, and health-related obstacles (with consultation from the transplant team) to create an individualized exercise and meal plan. The RDN will provide medical nutrition therapy via the nutrition care process throughout the course of the intervention. The Twistle Patient Engagement Platform will be used to deliver and collect survey data, communicate with participants, and promote retention. Outcomes to be assessed include intervention feasibility and acceptability and intervention efficacy on patients' adherence, medical, quality of life, and occupational outcomes.

Ambulatory blood pressure trajectories and blood pressure variability in kidney transplant recipients: a comparative study against haemodialysis patients

Background

Hypertension is the most prevalent cardiovascular risk factor in kidney transplant recipients (KTRs). Preliminary data suggest similar ambulatory blood pressure (BP) levels in KTRs and haemodialysis (HD) patients. This is the first study comparing the full ambulatory BP profile and short-term BP variability (BPV) in KTRs versus HD patients.

Methods

A total of 204 KTRs were matched (2:1 ratio) with 102 HD patients for age and gender. BP levels, BP trajectories and BPV indices over a 24-h ambulatory BP monitoring (ABPM) in KTRs were compared against both the first and second 24-h periods of a standard 48-h ABPM in HD patients. To evaluate the effect of renal replacement treatment and time on ambulatory BP levels, a two-way ANOVA for repeated measurements was performed.

Results

KTRs had significantly lower systolic blood pressure (SBP) and pulse-pressure (PP) levels compared with HD patients during all periods studied (24-h SBP: KTR: 126.5 ± 12.1 mmHg; HD first 24 h: 132.0 ± 18.1 mmHg; P = 0.006; second 24 h: 134.3 ± 17.7 mmHg; P < 0.001); no significant differences were noted for diastolic blood pressure levels with the exception of the second nighttime. Repeated measurements ANOVA showed a significant effect of renal replacement therapy modality and time on ambulatory SBP levels during all periods studied, and a significant interaction between them; the greatest between-group difference in BP (KTRs-HD in mmHg) was observed at the end of the second 24 h [-13.9 mmHg (95% confidence interval -21.5 to -6.2); P < 0.001]. Ambulatory systolic and diastolic BPV indices were significantly lower in KTRs than in HD patients during all periods studied (24-h SBP average real variability: KTRs: 9.6 ± 2.3 mmHg; HD first 24 h: 10.3 ± 3.0 mmHg; P = 0.032; second 24 h: 11.5 ± 3.0 mmHg; P < 0.001). No differences were noted in dipping pattern between the two groups.

Conclusions

SBP and PP levels and trajectories, and BPV were significantly lower in KTRs compared with age- and gender-matched HD patients during all periods studied. These findings suggest a more favourable ambulatory BP profile in KTRs, in contrast to previous observations.

Comparison of left ventricular subclinical systolic dysfunction between hemodialysis patients and renal transplant recipients using real time three-dimensional echocardiography

AIMS

The relationship between chronic kidney disease and development of heart failure is a well-known clinical entity. Systolic dyssynchrony index (SDI_16) is a new diagnostic tool for detection of subclinical left ventricular (LV) systolic dysfunction by using three-dimensional echocardiography (3DE). We aimed to investigate this parameter in patients with end-stage renal disease who were receiving hemodialysis and patients with renal transplant compared to healthy control subjects.

MATERIAL AND METHODS

Forty-five hemodialysis patients, 45 patients with renal transplant and 45 age-sex matched healthy control subjects included in the study. All participants were evaluated with 3DE in the interdialytic phase for measurement of LV volumes, ejection fraction and SDI_16 parameter.

RESULTS

Both LV diastolic and systolic volumes were significantly higher in hemodialysis group compared to renal transplant group and healthy controls, but this finding did not translate to a statistically significant difference for LVEF measurements between groups (58.71 ± 3.53 vs. 57.17 ± 2.97 vs. 59.23 ± 3.26, p = .16 for renal transplant and hemodialysis and healthy control groups, respectively). Mean value of SDI_16 parameters was significantly higher in hemodialysis group compared to renal transplant group (7.93 ± 2.50 vs. 3.72 ± 1.71, p < .001) and healthy controls (7.93 ± 2.50 vs. 3.00 ± .99, p < .001); whereas, it was similar between renal transplant group and control subjects (3.72 ± 1.71 vs. 3.00 ± .99, p = .10).

CONCLUSION

SDI_16 was significantly higher in hemodialysis patients compared to patients with renal transplant and healthy controls.

Nutritional Predictors of Cardiovascular Risk in Patients after Kidney Transplantation-Pilot Study

Asymmetric dimethylarginine (ADMA) is a marker of endothelial damage. Research confirms the association of ADMA with an increased cardiovascular risk (CVR) among kidney transplant recipients (KTRs). Additionally, increased circulating levels of fibroblast growth factor 23 (FGF-23) are associated with pathological cardiac remodeling and vascular alterations. The aim of the study is the analysis of the relationship between ADMA, FGF-23, nutritional, biochemical parameters in healthy subjects and KTRs. 46 KTRs and 23 healthy volunteers at mean age of 50.8 ± 15.4 and 62.5 ± 10.7 years were enrolled. The anthropometric and biochemical parameters such as ADMA, FGF-23, albumin, prealbumin were assessed. Fat tissue mass among KTRs was 30.28 ± 9.73%, lean body mass 64.5 ± 14.8%. Overweight and obesity was presented by 65.2% of recipients. Albumin level was 38.54 ± 3.80 g/L, prealbumin 27.83 ± 7.30 mg/dL and were significantly lower than in the control (p < 0.05). Patients with ADMA > 0.66 µmol/L had a lower concentration of prealbumin, albumin and increased concentration of oxidized low density lipoprotein (oxLDL), high sensitive C-reactive protein (hsCRP) and FGF-23. FGF-23 was significantly higher in patients with higher hsCRP (p < 0.05). KTRs with elevated ADMA had a longer transplantation vintage, lower eGFR and higher albuminuria. Diabetes mellitus (DM) was associated with higher levels of ADMA and FGF-23. Even in stable KTRs a relationship between inflammatory state, nutritional status, graft function and endothelial dysfunction biomarkers was observed.

Racial Differences in Medication Utilization for Secondary Prevention of Cardiovascular Disease in Kidney Transplant Recipients: A Post Hoc Analysis of the FAVORIT Trial Cohort

Rationale & Objective

Black kidney transplant recipients have higher prevalences of cardiovascular disease (CVD) risk factors and less intensive risk factor control than White kidney transplant recipients. Our objective was to evaluate racial disparities in receipt of statins and aspirin for secondary CVD prevention among kidney transplant recipients in the Folic Acid for Vascular Outcome Reduction in Transplantation (FAVORIT) trial.

Study Design

Cohort study.

Setting & Participants

FAVORIT participants of White, Black, and Other races from the United States and Canada with a history of CVD at study entry or who experienced a nonfatal CVD event during follow-up.

Predictor

Race.

Outcome

Receipt of statins and aspirin for secondary CVD prevention.

Analytical Approach

We used parametric (Weibull), proportional-hazards, interval-censored survival models to evaluate the independent association of race with receipt of statins and aspirin for secondary CVD prevention.

Results

Of the 4,110 kidney transplant recipients enrolled in FAVORIT trial, 978 met the inclusion criteria (78% White, 17% Black, and 6% Other race). Compared with the White race, Black and Other races were associated with lower hazards of receiving statins (Black race: adjusted HR, 0.76 [95% CI, 0.60-0.97]; Other race: adjusted HR, 0.87 [95% CI, 0.60-1.27]) and aspirin (Black race: adjusted HR, 0.85 [95% CI, 0.67-1.08]; Other race: adjusted HR, 0.63 [95% CI, 0.43-0.94]).

Limitations

Lack of granular information on potential indications or contraindications for aspirin or statin use for secondary CVD prevention.

Conclusions

Post hoc findings from the FAVORIT trial demonstrated that Black race was associated with a lower likelihood of receiving statins and Other race was associated with a lower likelihood of receiving aspirin for secondary CVD prevention. This represents a potential target to improve CVD care in non-White kidney transplant recipients.

Time-dependent cardiac structural and functional changes after kidney transplantation: a multi-parametric cardiac magnetic resonance study

OBJECTIVES

To map time-dependent cardiac structural and functional change patterns after renal transplantation (KT) using cardiac magnetic resonance (CMR).

METHODS

Fifty-three patients with pre-KT and post-KT CMR exams were retrospectively analyzed. Patients were divided into three groups according to the time of post-KT CMR: group 1 (3 months post-KT, n = 16), group 2 (6 months post-KT, n = 21), and group 3 (over 9 months post-KT, n = 16). Twenty-one age- and sex-matched healthy controls (HC) were recruited for the study. CMR-derived left ventricular (LV) volumes, LV mass index (LVMi), LV ejection fraction (LVEF), global radial strain (GRS), global circumferential strain (GCS), global longitudinal strain (GLS), and native T1 value were compared. The association between the changes of CMR parameters was assessed.

RESULTS

LVMi post-KT decreased in groups 2 (p < 0.001) and 3 (p = 0.004) but both groups had higher LVMi values compared to HC (both p < 0.001). GLS post-KT was decreased in group 1 (p = 0.021), but slightly increased in group 2 (p = 0.728) and group 3 (p = 0.100) without significant difference. GLS post-KT in group 3 was not different from HC (p = 0.104). LVEF, GRS, and GCS post-KT in groups 2 and 3 significantly increased and showed no significant difference from HC. The post-KT native T1 value in all three groups significantly decreased; however, no group showed any significant difference from HC. The change of LVEF was associated with the change of GCS, GRS, and GLS.

CONCLUSIONS

Although GRS, GCS, GLS, and native T1 values reversed to normal level, LVMi remained impaired in median 14 months after KT.

KEY POINTS

• Kidney transplantation has favorable effects on cardiac structure and function. • In a median 14 months of follow-up after KT, left ventricle strain and native T1 value reversed to normal level while LV mass index (LVMi) did not. Left ventricular hypertrophy may help to explain why KT recipients are still at increased cardiovascular risk. • The reason for the decrease of native T1 value after KT may be more than myocardial fibrosis and needs to be further studied.

The Impact of Kidney Transplantation on the Serum Fatty Acid Profile in Patients with End-Stage Kidney Disease

Epidemiological data indicate that metabolic disturbances and increased cardiovascular risk in renal transplant patients are a significant and common problem. Therefore, it is important to search for new solutions and, at the same time, counteract the negative effects of currently used therapies. In this study, we examined the effect of kidney transplantation on the serum levels of fatty acids (FAs) in order to assess the role of these compounds in the health of transplant patients. The FA profile was analyzed by gas chromatography-mass spectrometry in the serum of 35 kidney transplant recipients, just before transplantation and 3 months later. The content of total n-3 polyunsaturated FAs (PUFAs) decreased after transplantation (3.06 ± 0.13% vs. 2.66 ± 0.14%; p < 0.05). The total amount of ultra-long-chain FAs containing 26 and more carbon atoms was significantly reduced (0.08 ± 0.009% vs. 0.05 ± 0.007%; p < 0.05). The desaturation index (18:1/18:0) increased after transplantation (3.92 ± 0.11% vs. 4.36 ± 0.18%; p < 0.05). The study showed a significant reduction in n-3 PUFAs in renal transplant recipients 3 months after transplantation, which may contribute to increased cardiovascular risk in this patient population.

Cardiovascular changes in young renal failure patients

Progresses in medical care of severe kidney disease and congenital anomalies of kidney and urinary tract make it possible for a higher percentage of young renal failure patients to survive and enter adulthood. There is thus an increasing need to focus on the long-term effects of severely reduced kidney function early in life. Cardiovascular changes are known to contribute considerably in adulthood to the severe complications of renal failure. In young chronic kidney disease patients, there is limited knowledge of subclinical cardiovascular disease. In this issue of Clinical Kidney Journal, Lalayiannis et al. describe significant structural and functional cardiovascular changes in a young cohort of kidney failure patients with glomerular filtration rate <30 mL/min/1.73 m². Among the 100 patients between 5 and 30 years of age included in the study, 84 presented with signs of cardiovascular disease. There is a need for long-term follow-up data on cardiovascular consequences of renal failure early in life and evaluation of prophylactic and therapeutic measures that can ameliorate the overall prognosis for these patients. We look forward to planned future long-term data from this cohort as well as increased focus in general on cardiovascular changes in young renal failure patients.

Valvular Heart Disease in Patients with Chronic Kidney Disease

Valvular heart disease (VHD) is highly prevalent in patients with chronic kidney disease (CKD) from the early stages to end-stage renal disease (ESRD). Aortic and mitral valves are the most frequently affected, leading to aortic valve and/or mitral annular calcification, which, in turn, causes either valve stenosis or regurgitation at an accelerated rate compared with the general population. Tricuspid regurgitation is also prevalent in CKD and ESRD, and haemodialysis patients are at an increasingly high risk of infective endocarditis. As for pathophysiology, several mechanisms causing VHD in CKD have been proposed, highlighting the complexity of the process. Echocardiography constitutes the gold standard for the assessment of VHD in CKD/ESRD patients, despite the progress of other imaging modalities. With regard to treatment, the existing 2017 European Society of Cardiology/European Association for Cardio-Thoracic Surgery guidelines on the management of VHD addressing patients with normal kidney function are also applied to patients with CKD/ESRD.

Mitral and Aortic Regurgitation in Patients Undergoing Kidney Transplantation: The Natural Course and Factors Associated With Progression

Background

Valve regurgitation can decrease with resolution of hemodynamic loads on the left ventricle (LV) after kidney transplantation (KT). We aimed to investigate the natural course of left-side valve regurgitation after KT and factors associated with progression.

Methods

Among patients who underwent KT in two tertiary centers, 430 (224 men, mean age 50 ± 13 years) were examined by echocardiography within 3 months before KT and between 6 and 36 months after KT. Mitral regurgitation (MR) and aortic regurgitation (AR) were graded according to the current guidelines. Regression was defined as a decrease in regurgitation by one or more steps, and progression was an increase in one or more steps after KT. Clinical and echocardiographic factors associated with progression of MR and AR were analyzed.

Results

Mild or greater MR was observed in 216 (50%) patients before KT, and mild or greater AR was observed in 99 (23%). During the follow-up period of 23.4 ± 9.9 months, most patients experienced regression or no change in regurgitation after KT, but 34 patients (7.9%) showed MR progression and 37 (8.6%) revealed AR progression. Patients who showed MR progression were more likely to receive a second KT, have mitral annular calcifications, and show a smaller decrease in LV end-systolic dimension. Patients who showed AR progression were more likely to have persistent hypertension after KT, aortic valve calcifications, and a smaller reduction of LV end-systolic dimension.

Conclusions

Risk factors for progression of MR after KT include a second KT, MAC and a smaller decrease in LV end-systolic dimension after KT. Risk factors for progression of AR include valve calcification, persistent hypertension and a smaller decrease in LV end-systolic dimension after KT. Further echocardiographic surveillance and risk factor management after KT are warranted in these patients.

Association of obesity with mortality and clinical outcomes in children and adolescents with transplantation: A systematic review and meta-analysis

Obesity might be associated with mortality and clinical outcomes following transplantation; however, the direction of this relationship has not been well-recognized in youth. The aim of this systematic review and meta-analysis was to investigate the association of obesity with post-transplant mortality and clinical outcomes in children and adolescents. Following a systematic search of observational studies published by December 2018 in PubMed, Scopus, Embase, and Cochrane library, 15 articles with total sample size of 50,498 patients were included in the meta-analysis. The main outcome was mortality and secondary outcomes included acute graft versus host disease (GVHD), acute rejection, and overall graft loss. The pooled data analyses showed significantly higher odds of long term mortality (OR 1.30, 95% CI 1.15-1.48, P < 0.001, I² = 50.3%), short term mortality (OR 1.79, 95% CI 1.19-2.70, P = 0.005, I² = 59.6%), and acute GVHD (OR 2.13, 95% CI 1.5-3.02, P < 0.001, I² = 1.7%) in children with obesity. There were no significant differences between patients with and without obesity in terms of acute rejection (OR 1.07, 95% CI 0.98-1.16, P = 0.132, I² = 7.5%) or overall graft loss (OR 1.04, 95% CI 0.84-1.28, P = 0.740, I² = 51.6%). This systematic review and meta-analysis has stated higher post-transplant risk of short and long term mortality and higher risk of acute GVHD in children with obesity compared to those without obesity. Future clinical trials are required to investigate the effect of pre-transplant weight management on post-transplant outcomes to provide insights into the clinical application of these findings. This may in turn lead to establish guidelines for the management of childhood obesity in transplantations.

Post-Transplant Cardiovascular Disease

Cardiovascular disease remains a leading cause of death and morbidity in kidney transplant recipients and a common reason for post-transplant hospitalization. Several traditional and nontraditional cardiovascular risk factors exist, and many of them present pretransplant and worsened, in part, due to the addition of immunosuppression post-transplant. We discuss optimal strategies for identification and treatment of these risk factors, including the emerging role of sodium-glucose cotransporter 2 inhibitors in post-transplant diabetes and cardiovascular disease. We present common types of cardiovascular disease observed after kidney transplant, including coronary artery disease, heart failure, pulmonary hypertension, arrhythmia, and valvular disease. We also discuss screening, treatment, and prevention of post-transplant cardiac disease. We highlight areas of future research, including the need for goals and best medications for risk factors, the role of biomarkers, and the role of screening and intervention.

3D Echocardiography - A Useful Method for Cardiovascular Risk Assessment in End-Stage Renal Disease Patients

Patients with chronic kidney disease (CKD) have an increased risk of premature mortality, mainly due to cardiovascular causes. The association between hemodialysis and accelerated atherosclerosis has long been described. The ankle-brachial index (ABI) is a surrogate marker of atherosclerosis and recent studies indicate its utility as a predictor of future cardiovascular disease and all-cause mortality. The clinical implications of ABI cut-points are not well defined in patients with CKD. Echocardiography is the most widely used imaging method for cardiac evaluation. Structural and functional myocardial abnormalities are common in patients with CKD due to pressure and volume overload as well as non-hemodynamic factors associated with CKD. Our study aimed to identify markers of subclinical cardiovascular risk assessed using ABI and 2D and 3D echocardiographic parameters evaluating left ventricular (LV) structure and function in patients with end-stage renal disease (ESRD) (patients undergoing dialysis), patients after kidney transplantation and non-ESRD patients (control). In ESRD, particularly in hemodialysis patients, changes in cardiac structure, rather than function, seems to be more pronounced. 3D echocardiography appears to be more sensitive than 2D echocardiography in the assessment of myocardial structure and function in CKD patients. Particularly 3D derived end-diastolic volume and 3D derived LV mass indexed for body surface appears to deteriorate in dialyzed and transplanted patients. In 2D echocardiography, myocardial mass represented by left ventricular mass/body surface area index (LVMI) appears to be a more sensitive marker of cardiac structural changes, compared to relative wall thickness (RWT), left ventricle and diastolic diameter index (LVEDDI) and left atrial volume index (LAVI). We observed a generally favorable impact of kidney transplantation on cardiac structure and function; however, the differences were non-significant. The improvement seems to be more pronounced in cardiac function parameters, peak early diastolic velocity/average peak early diastolic velocity of mitral valve annulus (E/e´), 3D left ventricle ejection fraction (LV EF) and global longitudinal strain (GLS). We conclude that ABI is not an appropriate screening test to determine the cardiovascular risk in patients with ESRD.

Positive Association of Serum Adiponectin Level With the Vascular Reactivity Index in Kidney Transplant Patients

OBJECTIVES

Adiponectin has an important role in obesity, insulin resistance, and cardiovascular disease. We investigated the association between serum adiponectin levels and endothelial function in kidney transplant patients.

MATERIALS AND METHODS

Fasting blood samples were obtained from 70 kidney transplant patients. The vascular reactivity index was measured with a digital thermal monitoring test. Serum adiponectin levels were measured with a commercially available enzyme immunoassay kit. A vascular reactivity index <1.0 was defined as poor, 1.0 or greater but less than 2.0 was intermediate, and 2.0 or greater was good.

RESULTS

The results showed that 10 kidney transplant patients (13.3%) were categorized with a vascular reactivity index of poor, 25 (35.7%) were intermediate, and 35 (50%) were good. Increased waist circumference (P = .037), increased serum alkaline phosphatase (P = .026), and lower serum adiponectin (P = .001) were associated with poor vascular reactivity index. Advanced age (r = -0.300; P = .012), waist circumference (r = -0.372; P = .002), serum alkaline phosphatase (r = -0.323; P = .006), and logarithmically transformed serum triglycerides (r = -0.317; P = .007) were negatively correlated with the vascular reactivity index, whereas serum adiponectin (r = 0.332; P = .005) was positively correlated with the vascular reactivity index. Multi variable forward stepwise linear regression analysis showed that waist circumference, serum alkaline phosphatase, and serum adiponectin were significantly and independently associated with the vascular reactivity index.

CONCLUSIONS

Fasting serum adiponectin levels were positively associated with the vascular reactivity index and negatively associated with endothelial function in kidney transplant patients.

Characteristics and Prognosis of Stroke in Living Donor Renal Transplant Recipients

Aims: We aimed to determine the characteristics and vascular outcomes of stroke in renal transplant (RT) recipients and compare them with those in patients on hemodialysis (HD) and those with no renal replacement therapy (RRT).

Methods: In this prospective observational study, 717 patients (mean age, 70.8 years; male, 60.5%) with acute ischemic stroke within one week of onset were consecutively enrolled and followed for one year. The patients were classified into three groups: (1) living donor RT recipients (n=27); (2) patients on maintenance HD before the index stroke (n=39); and (3) those with no history of RRT (n=651). The primary outcome was a composite of major adverse cardiovascular events (MACE).

Results: Diabetic nephropathy was the most common reason for RRT in both RT and HD patients. RT patients were more likely to have embolic stroke of undetermined source (33.3%) than others, whereas HD patients more often had cardioembolism (51.3%). No difference was observed in the MACE risk between the patients in RT and non-RRT groups (annual rate, 11.3% vs. 13.1%; log-rankP=0.82; hazard ratio [95% confidence interval], 0.92 [0.29-2.98]). In contrast, HD patients had a greater risk of MACE than those with no RRT (annual rate, 28.2% vs. 13.1%; log-rankP=0.019; hazard ratio [95% confidence interval], 2.24 [1.16-4.3]).

Conclusions: The underlying etiologies of stroke differed in RT and HD patients. The one-year risk of MACE for stroke patients who had received an RT was lower than that for patients undergoing HD and comparable with that of patients with no RRT.

But Why Weight: Understanding the Implications of Obesity in Kidney Transplant

Obesity is increasing in prevalence among candidates for kidney transplant. Understanding the influence of obesity on candidate evaluation, surgical risk, peritransplant management, and post-transplant outcomes is critical to ensuring equitable access to transplant for this growing population.

Risk of post-transplant cardiovascular events in kidney transplant recipients with preexisting aortoiliac stenosis

Prediction of the risk of cardiovascular events (CVE's) is important to optimize outcomes after kidney transplantation. Aortoiliac stenosis is frequently observed during pre‐transplant screening. We hypothesized that these patients are at higher risk of post‐transplant CVE's due to the joint underlying atherosclerotic disease. Therefore, we aimed to assess whether aortoiliac stenosis was associated with post‐transplant CVE's. This retrospective, single‐center cohort study included adult kidney transplant recipients, transplanted between 2000 and 2016, with contrast‐enhanced imaging available. Aortoiliac stenosis was classified according to the Trans‐Atlantic Inter‐Society Consensus (TASC) II classification and was defined as significant in case of ≥50% lumen narrowing. The primary outcome was CVE‐free survival. Eighty‐nine of 367 patients had significant aortoiliac stenosis and were found to have worse CVE‐free survival (median CVE‐free survival: stenosis 4.5 years (95% confidence interval (CI) 2.8–6.2), controls 8.9 years (95% CI 6.8–11.0); log‐rank test P < .001). TASC II C and D lesions were independent risk factors for a post‐transplant CVE with a hazard ratio of 2.15 (95% CI 1.05–4.38) and 6.56 (95% CI 2.74–15.70), respectively. Thus, kidney transplant recipients with TASC II C and D aortoiliac stenosis require extensive cardiovascular risk management pre‐, peri,‐ and post‐transplantation.

Plasma xanthine oxidoreductase is associated with carotid atherosclerosis in stable kidney transplant recipients

AIM

Xanthine oxidoreductase (XOR) is known as an enzyme related to purine metabolism, catalysing the oxidation of hypoxanthine to xanthine and of xanthine to uric acid. We investigated the relationship between plasma XOR activity in stable kidney transplantation (KT) recipients and carotid artery lesions.

METHODS

A total of 42 KT patients visiting our outpatient clinic on regular basis were recruited. Associations between plasma XOR activity and the existence of plaque in the common carotid artery (CCA) or internal carotid artery (ICA) and maximum intima-medial thickness (IMT) of CCA (max-CIMT) > 0.9 mm were examined using univariate and multivariate analyses.

RESULTS

At blood sampling, the mean and SD patient age was 52.7 ± 13.8 years old. Plasma XOR(pmol/h/ml) activity was significantly higher in patients with CCA/ICA plaque or max-CIMT >0.9 mm than those without. [23.9 (11.8, 38.3) vs. 8.29 (6.67, 17.5), p < .01, 23.9 (16.9, 71.2) vs. 9.16 (6.67, 28.2), p = .01] Univariate and multivariate logistic regression analyses revealed age and plasma XOR activity as independent predictors of CCA/ICA plaque or max-CIMT >0.9 mm. Receiver operator characteristic curve analyses revealed that the cutoff value of plasma XOR activity for the diagnosis of CCA/ICA plaque or CCA-IMT > 0.9 mm was 16.3 pmol/h/ml.

CONCLUSION

Plasma XOR activity is associated independently with atherosclerotic changes in the carotid artery of stable post-KT patients.

Treatment of Mixed Dyslipidemia With Alirocumab in a Kidney Transplant Recipient: A Case Report

Dyslipidemia is common in kidney transplant recipients owing to the disturbance of lipid metabolism caused by chronic kidney disease and the effect of immunosuppression on lipid metabolism. Patients receiving treatment with mammalian target of rapamycin inhibitors show more prominent lipid disorders, which are attributed mainly, but not only, to adipocyte lipid uptake disruption, lipolysis promotion and lipogenic gene expression enhancement. Dyslipidemias in kidney transplant recipients predispose these patients to an increased risk of developing cardiovascular disease; thus, current guidelines recommend treatment initiation with a statin, regardless of low-density lipoprotein cholesterol (LDL-C) concentration, with ezetimibe as a secondary option for patients who do not tolerate such therapy or for those with inadequate response. Treatment with pro-protein convertase subtilisin/kexin type 9 inhibitors such as alirocumab, although effectively reducing LDL-C in patients with chronic kidney disease, has not been evaluated in kidney transplant recipients. In this case report, we present a case of a female kidney transplant recipient who developed substantial dyslipidemia after everolimus initiation. This case was resistant to treatment with simvastatin/ezetimibe combination, and the patient subsequently received alirocumab. Our patient showed a mean reduction of 46.6% in LDL-C during an 18-month period after alirocumab initiation, which is comparable to the results of studies on patients with or without renal impairment. Furthermore, treatment with alirocumab proved to be well tolerated without adverse effects or interactions with the immunosuppression regimen.