Cardiovascular Disease Mortality in Kidney Transplant Recipients: No Light at the End of the Tunnel?

Outcomes of Older Primary Kidney Transplant Recipients by Induction Agent and High-risk Viral Discordance Status in the United States

Background

The impact of induction type or high-risk viral discordance on older kidney transplant recipients is unclear. Herein, we analyzed the association between induction type, viral discordance, and outcomes for older recipients.

Methods

We analyzed the Scientific Registry of Transplant Recipients standard analysis file for all primary kidney transplant recipients older than 55 y who were transplanted between 2005 and 2022. All transplants were crossmatch negative and ABO-compatible. Recipients were discharged on tacrolimus and mycophenolate ± steroids. Recipients were categorized into 3 groups by induction received: rabbit antithymocyte globulin (r-ATG; N = 51 079), interleukin-2 receptor antagonist (IL-2RA; N = 22 752), and alemtuzumab (N = 13 465). Kaplan-Meier curves were generated for recipient and graft survival, and follow-up was censored at 10 y. Mixed-effect Cox proportional hazard models examined the association between induction type, high-risk viral discordance, and outcomes of interest. Models were adjusted for pertinent recipient and donor characteristics.

Results

Induction type did not predict recipient survival in the multivariable model, whereas Epstein-Barr virus high-risk discordance predicted 14% higher mortality (1.14 [1.07-1.21], P < 0.01). In the multivariable model for death-censored graft survival, alemtuzumab, but not IL-2RA, was associated with an increased risk of graft loss (1.18 [1.06-1.29], P < 0.01) compared with r-ATG. High-risk cytomegalovirus discordance predicted 10% lower death-censored graft survival (1.10 [1.01-1.19], P < 0.02). Live donor and preemptive transplantation were favorable predictors of survival.

Conclusions

In this large cohort of older transplant recipients, alemtuzumab, but not IL-2RA, induction was associated with an increased risk of graft loss compared with r-ATG. Cytomegalovirus and Epstein-Barr virus high-risk viral discordance portended poor graft and recipient survival, respectively.

Chronic kidney disease progression in kidney transplant recipients: A focus on traditional risk factors

Kidney transplant recipients are a subset of patients with chronic kidney disease (CKD) that remain at high risk for progression to dialysis and mortality. Recent advances in immunosuppression have only partially improved long-term graft and patient survival. Discovery of new immunosuppressive regimens is a slow and resource-intensive process. Hence, recognition and management of modifiable allogeneic and non-allogeneic risk factors for progression to CKD among kidney transplant recipients is of major interest for improving long-term outcomes. Graft survival is mainly determined by the quality of the allograft and by the patient's alloimmune response, which is influenced by human leukocyte antigen matching and the presence of donor-specific antibodies. Alloimmune responses manifest as acute and chronic forms of cell- and antibody-mediated rejection, which can be worsened by patient non-adherence or under-immunosuppression. However, donor and patient ages, glomerular disease recurrence, time on dialysis, pre-existing cardiovascular burden, medication side-effects and traditional risk factors, such as hypertension, proteinuria, anaemia, dyslipidaemia, diabetes and bone mineral disorder, which can ultimately lead to severe endothelial derangement, also contribute to graft loss and mortality. These traditional risk factors, common to pre-dialysis patients, often are considered of secondary importance when compared to alloimmunity and immunosuppression concerns. In this review article, we focus on the epidemiological, pathophysiological and therapeutic features of non-allogeneic traditional risk factors for CKD. We also discuss the benefit of adopting a multidisciplinary approach to pursue the same therapeutic targets recommended for pre-dialysis patients.

New-onset diabetes after liver transplantation and its impact on complications and patient survival

BACKGROUND

The aim of the present study was to investigate the incidence and risk factors of new-onset diabetes after transplantation (NODAT) in liver transplant recipients and the influence of NODAT on complications and long-term patient survival.

METHODS

We examined 438 patients who underwent liver transplantation between April 2001 and December 2008 and were not diabetic before transplantation.

RESULTS

The mean (± SD) follow-up duration was 2.46 ± 1.62 years. The incidence of NODAT 3, 6, 9, 12, 36, and 60 months after transplantation was 44.24%, 25.59%, 23.08%, 25.17%, 17.86%, and 18.18%, respectively. Multifactor analysis indicated that preoperative fasting plasma glucose (FPG) levels and donor liver steatosis were independent risk factors for NODAT, whereas administration of an interleukin-2 receptor (IL-2R) antagonist reduced the risk of NODAT. Compared with the no NODAT group (N-NODAT), the NODAT group had a higher rate of sepsis and chronic renal insufficiency. Mean survival was significantly longer in the N-NODAT than NODAT group. Cox regression analysis showed that pre- and/or postoperative FPG levels, tumor recurrence or metastasis, and renal insufficiency after liver transplantation were independent risk factors of mortality. Pulmonary infection or multisystem failure were specific causes of death in the NODAT group, whereas patients in both groups died primarily from tumor relapse or metastasis.

CONCLUSIONS

Preoperative FPG levels and donor liver steatosis were independent risk factors for NODAT, whereas administration of an IL-2R antagonist reduced the risk of NODAT. Patients with NODAT had reduced survival and an increased incidence of sepsis and chronic renal insufficiency. Significant causes of death in the NODAT group were pulmonary infection and multisystem failure.

Restoration of renal function does not correct impairment of uremic HDL properties

Cardiovascular disease remains the leading cause of death in renal transplant recipients, but the underlying causative mechanisms for this important problem remain elusive. Recent work has indicated that qualitative alterations of HDL affect its functional and compositional properties in ESRD. Here, we systematically analyzed HDL from stable renal transplant recipients, according to graft function, and from patients with ESRD to determine whether structural and functional properties of HDL remain dysfunctional after renal transplantation. Cholesterol acceptor capacity and antioxidative activity, representing two key cardioprotective mechanisms of HDL, were profoundly suppressed in kidney transplant recipients independent of graft function and were comparable with levels in patients with ESRD. Using a mass spectroscopy approach, we identified specific remodeling of transplant HDL with highly enriched proteins, including α-1 microglobulin/bikunin precursor, pigment epithelium-derived factor, surfactant protein B, and serum amyloid A. In conclusion, this study demonstrates that HDL from kidney recipients is uniquely altered at the molecular and functional levels, indicating a direct pathologic role of HDL that could contribute to the substantial cardiovascular risk in the transplant population.