Long Graft Cold Ischemia Time Is Associated With Increased Arterial Stiffness in Renal Transplant Recipients

Impact of immunosuppressive therapy on arterial stiffness in kidney transplantation: are all treatments the same?

Arterial stiffness is a biologic process related to ageing and its relationship with cardiovascular risk is well established. Several methods are currently available for non-invasive measurement of arterial stiffness that provide valuable information to further assess patients’ vascular status in real time. In kidney transplantation recipients, several factors could accelerate the stiffness process, such as the use of calcineurin inhibitors (CNIs), the presence of chronic kidney disease and other classical cardiovascular factors, which would explain, at least in part, the high cardiovascular mortality and morbidity. Despite the importance of arterial stiffness as a biomarker of cardiovascular risk, and unlike other cardiovascular risk factors (e.g. left ventricular hypertrophy), only a few clinical trials or retrospective studies of kidney recipients have evaluated its impact. In this review we describe the clinical impact of arterial stiffness as a prognostic marker of cardiovascular disease and the effects of different immunosuppressive regimens on its progression, focusing on the potential benefits of CNI-sparing protocols and supporting the rationale for individualization of immunosuppression in patients with lower arterial elasticity. Among the immunosuppressive drugs, a belatacept-based regimen seems to offer better vascular protection compared with CNIs, although further studies are needed to confirm the preliminary positive results.

Evaluation of arterial structure and function in pediatric patients with end-stage renal disease on dialysis and after renal transplantation

CVD is a major cause of morbidity and mortality in pediatric patients with CKD. It is unclear whether vascular abnormalities in these patients are reversible, and if transplantation portends salutary effects on arterial function. We compared FMD, PWV, AI75, and CIMT in 15 dialysis (D), 14 transplant patients (T), and 15 controls (C), and their associations with cardiovascular risk factors. There was stepwise lower FMD (p < 0.001), higher AI75 (p < 0.001), higher PWV (p = 0.01), and higher CIMT SDS for age (p = 0.03) and height (p = 0.006) in the D group than T and C groups. FMD, PWV, and CIMT were unrelated to dialysis duration or time from transplantation. On multivariate analysis, group status was independently associated with FMD (β = 3.15, p = 0.002), AI75 (β = -5.95, p = 0.01), PWV (β = -0.57, p = 0.07) and CIMT (β = -0.02, p = 0.04) and CIMT SDS for height (β = -0.541, p = 0.009). FMD is lower and AI75, PWV and CIMT are higher in pediatric patients maintained on D than T/C. T patients have similar AI75, PWV and CIMT to C although FMD remains reduced. These findings suggest that transplantation stabilizes or improves CKD associated arteriopathy.

Immunosuppressant regimen based on sirolimus decreases aortic stiffness in renal transplant recipients in comparison to cyclosporine

Whether or not a cyclosporine A (CsA)-free immunosuppressant regimen based on sirolimus (SRL) prevents aortic stiffening and improves central hemodynamics in renal recipients remains unknown. Forty-four patients (48 ± 2 years) enrolled in the CONCEPT trial were randomized at week 12 (W12) to continue CsA or switch to SRL, both associated with mycophenolate mofetil. Carotid systolic blood pressure (cSBP), pulse pressure (cPP), central pressure wave reflection (augmentation index, AIx) and carotid-to-femoral pulse-wave velocity (PWV: aortic stiffness) were blindly assessed at W12, W26 and W52 together with plasma endothelin-1 (ET-1), thiobarbituric acid-reactive substances (TBARS) and superoxide dismutase (SOD) and catalase erythrocyte activities. At W12, there was no difference between groups. At follow-up, PWV, cSBP, cPP and AIx were lower in the SRL group. The difference in PWV remained significant after adjustment for blood pressure and eGFR. In parallel, ET-1 decreased in the SRL group, while TBARS, SOD and catalase erythrocyte activities increased in both groups but to a lesser extent in the SRL group. Our results demonstrate that a CsA-free regimen based on SRL reduces aortic stiffness, plasma endothelin-1 and oxidative stress in renal recipients suggesting a protective effect on the arterial wall that may be translated into cardiovascular risk reduction.