Differential impact of belatacept and cyclosporine A on central aortic blood pressure and arterial stiffness after renal transplantation

Cardiovascular Risk Following Conversion to Belatacept From a Calcineurin Inhibitor in Kidney Transplant Recipients: A Randomized Clinical Trial

Rationale & Objective

In kidney transplant recipients (KTRs), a belatacept-based immunosuppressive regimen is associated with beneficial effects on cardiovascular (CV) risk factors compared with calcineurin inhibitor (CNI)-based regimens. Our objective was to compare the calculated CV risk between belatacept and CNI (predominantly tacrolimus) treatments using a validated model developed for KTRs.

Study Design

Prospective, randomized, open-label, parallel-group, investigator-initiated, international multicenter trial.

Setting & Participants

KTRs aged 18-80 years with a stable graft function (estimated glomerular filtration rate > 20 mL/min/1.73 m²), 3-60 months after transplantation, treated with tacrolimus or cyclosporine A, were eligible for inclusion.

Intervention

Continuation with a CNI-based regimen or switch to belatacept for 12 months.

Outcomes

Comparison of the change in the estimated 7-year risk of major adverse CV events and all-cause mortality, changes in traditional markers of CV health, as well as measures of arterial stiffness.

Results

Among the 105 KTRs randomized, we found no differences between the treatment groups in the predicted risk for major adverse CV events or mortality. Diastolic blood pressure, measured both centrally by using a SphygmoCor device and peripherally, was lower after the belatacept treatment than after the CNI treatment. The mean changes in traditional cardiovascular (CV) risk factors, including kidney transplant function, were otherwise similar in both the treatment groups. The belatacept group had 4 acute rejection episodes; 2 were severe rejections, of which 1 led to graft loss.

Limitations

The heterogeneous baseline estimated glomerular filtration rate and time from transplantation to trial enrollment in the participants. A limited study duration of 1 year.

Conclusions

We found no effects on the calculated CV risk by switching to the belatacept treatment. Participants in the belatacept group had not only lower central and peripheral diastolic blood pressure but also a higher rejection rate.

Funding

The trial has received a financial grant from Bristol-Myers Squibb.

Trial Registration

EudraCT no. 2013-001178-20.

Updated Pathways in Cardiorenal Continuum after Kidney Transplantation

Cardiovascular disease (CVD) remains one of the leading causes for increased morbidity and mortality in chronic kidney disease (CKD). Kidney transplantation is the preferred treatment option for CKD G5. Improved perioperative and postoperative care, personalized immunosuppressive regimes, and refined matching procedures of kidney transplants improves cardiovascular health in the early posttransplant period. However, the long-term burden of CVD is considerable. Previously underrecognized, the role of the complement system alongside innate immunity, inflammaging, structural changes in the glomerular filtration barrier and early vascular ageing also seem to play an important role in the posttransplant management. This review provides up-to-date knowledge on these pathways that may influence the cardiovascular and renal continuum and identifies potential targets for future therapies. Arterial destiffening strategies and the applicability of sodium-glucose cotransporter 2 inhibitors and their role in cardiovascular health after kidney transplantation are also addressed.

Influence of Belatacept- vs. CNI-Based Immunosuppression on Vascular Stiffness and Body Composition

Background: Arterial stiffness and phase angle (PhA) have gained importance as a diagnostic and prognostic parameter in the management of cardiovascular disease. There are few studies regarding the differences in arterial stiffness and body composition between renal transplant recipients (RTRs) receiving belatacept (BELA) vs. calcineurin inhibitors (CNI). Therefore, we investigated the differences in arterial stiffness and body composition between RTRs treated with different immunosuppressants, including BELA. Methods: In total, 325 RTRs were enrolled in the study (mean age 52.2 years, M −62.7%). Arterial stiffness was determined with an automated oscillometric device. All body composition parameters were assessed, based on bioelectrical impedance analysis (BIA), and laboratory parameters were obtained from the medical files of the patients. Results: We did not detect any significant difference in terms of arterial stiffness and PhA in RTRs undergoing different immunosuppressive regimens, based on CsA, Tac, or BELA. Age was an essential risk factor for greater arterial stiffness. The PhA was associated with age, BMI, time of dialysis before transplantation, and kidney graft function. Conclusion: No significant differences in arterial stiffness and PhA were observed in RTRs under different immunosuppressive regimens. While our data provide additional evidence for arterial stiffness and PhA in RTRs, more research is needed to fully explore these cardiovascular risk factors and the impact of different immunosuppressive regimens.

Potential Effects of Immunosuppression on Oxidative Stress and Atherosclerosis in Kidney Transplant Recipients

Chronic kidney disease is a public health problem that, depending on the country, affects approximately 8-13% of the population, involving both males and females of all ages. Renal replacement therapy remains one of the most costly procedures. It is assumed that one of the factors influencing the course of chronic kidney disease might be oxidative stress. It is believed that the main mediators of oxidative stress are reactive oxygen species (ROS). Transiently increased concentrations of ROS play a significant role in maintaining an organism's homeostasis, as they are part of the redox-related signaling, and in the immune defense system, as they are produced in high amounts in inflammation. Systemic oxidative stress can significantly contribute to endothelial dysfunction along with exaggeration of atherosclerosis and development of cardiovascular disease, the leading cause of mortality in patients with kidney disease. Moreover, the progression of chronic kidney disease is strictly associated with the atherosclerotic process. Transplantation is the optimal method for renal replacement therapy. It improves better quality of life and prolongs survival compared with hemodialysis and peritoneal dialysis; however, even a successful transplantation does not correct the abnormalities found in chronic kidney disease. As transplantation reduces the concentration of uremic toxins, which are a factor of inflammation per se, both the procedure itself and the subsequent immunosuppressive treatment may be a factor that increases oxidative stress and hence vascular sclerosis and atherosclerotic cardiovascular disease. In the current work, we review the effect of several risk factors in kidney transplant recipients as well as immunosuppressive therapy on oxidative stress.

Hemodynamic Effects of a Multidisciplinary Geriatric Rehabilitation Program

Background

Geriatric rehabilitation programs primarily aim at an increase of mobility and functional autonomy of the elderly. The cardiovascular effects of these programs, however, remain elusive. Since regular physical exercise is associated with numerous beneficial cardiovascular effects including a reduction of blood pressure (BP), the present prospective study investigates the hemodynamic effects of a representative standardized rehabilitation program.

Methods

A total of 74 subjects who were hospitalized in a German university hospital for geriatric rehabilitation were enrolled in the study. Peripheral BP, central aortic BP, 24h-ambulatory BP, heart rate and pulse wave velocity as a measure of arterial stiffness were assessed at admission and before discharge from the hospital. The program contained 4-5 sessions of physical activity of individualized intensity per week (≥30 min/session, eg, walking, cycling, stair rising).

Results

The mean age of the study population was 82.4±6.9 years; all patients suffered from arterial hypertension (stage 2-3) with a median number of three antihypertensive drugs. The most frequent cause for admission was injurious falls. The mean duration of the rehabilitation program was 17 days and comprised at least 20 physical activity sessions including occupational therapy. The program led to a significant improvement of mobility (Timed Up & Go 29.5±18.5 vs 19.1 ±9.3 s, p<0.001) and Barthel index of activities of daily living score (46.6±19.1 vs 69.8±16.5, p<0.001). Peripheral systolic BP decreased from 135.4±19.0 mmHg at baseline to 129.0±18.4 mmHg at follow-up (p=0.03), whereas peripheral diastolic BP, central aortic BP, 24h-ambulatory BP, heart rate and pulse wave velocity as a measure of arterial stiffness were not significantly altered (p>0.05 each).

Conclusion

The present representative standardized geriatric rehabilitation program was able to improve mobility, which showed a mild effect on systolic BP but did not affect 24h-ambulatory BP.

Arterial Stiffness Assessed by Oscillometric Method in Kidney Transplant, Predialysis, and Dialysis Patients

INTRODUCTION

Chronic kidney disease (CKD) is strongly associated with a higher risk of cardiovascular disease (CV). An important nontraditional risk factor of cardiovascular disease in renal patients is vascular stiffness, which currently can be evaluated by oscillometric measuring of pulse wave velocity (PWV) and heart rate-corrected augmentation index (AIx@75).

AIM

The aim of our study was to compare vascular stiffness between kidney transplant (KTx) recipients, patients on dialysis maintenance, and those in the predialysis period.

MATERIALS AND METHODS

A cross-sectional study of 140 patients (52 in CKD stage 3-4; 37 in CKD stage 5 on hemodialysis maintenance [HD]; and 51 KTx recipients) had their PWV and AIx@75 measured with Mobil-O-Graph (IEM Gmbh, Stolberg, Germany) blood and pulse pressure monitor.

RESULTS

KTx, HD, and CKD G3-4 were comparable in term of age, sex, body mass index, and diagnoses of diabetes mellitus and hypertension. The PWV was higher in the HD group than in the KTx and CKD G3-4 (9.4 m/s vs 8.4 m/s vs 7.9 m/s respectively; P < .05 for HD vs other groups), while the difference between the KTx and CKD G3-4 was not significant. AIx@75 values were similar in the HD and KTx groups (27.1 and 25.6; P > .05) and significantly lower in CDK G3-4 (17.8; P < .05).

CONCLUSIONS

According to our results, the highest CV risk expressed by PWV (vascular stiffness) was found in hemodialysis patients. Although patients with CKD 3-4 and after KTx showed comparable large artery stiffness, transplant recipients additionally showed higher stiffness in smaller arteries as measured by heart rate-corrected AIx.

Progression of endothelial dysfunction, atherosclerosis, and arterial stiffness in stable kidney transplant patients: a pilot study

Background

Kidney transplant patients suffer from vascular abnormalities and high cardiovascular event rates, despite initial improvements post-transplantation. The nature of the progression of vascular abnormalities in the longer term is unknown. This pilot study investigated changes in vascular abnormalities over time in stable kidney transplant patients long after transplantation.

Methods

Brachial artery flow-mediated dilation (FMD), nitroglycerin-mediated dilation, carotid-femoral pulse wave velocity (cf-PWV), ankle-brachial pressure index, and common carotid artery intima-media thickness (CCA-IMT) were assessed in 18 kidney transplant patients and 17 controls at baseline and 3–6 months after.

Results

There was no difference in age (51 ± 13 vs. 46 ± 11; P = 0.19), body mass index (26 ± 5 vs. 25 ± 3; P = 0.49), serum cholesterol (4.54 ± 0.96 vs. 5.14 ± 1.13; P = 0.10), systolic blood pressure (BP) (132 ± 12 vs. 126 ± 12; P = 0.13), diastolic BP (82 ± 9 vs. 77 ± 8; P = 0.10), or diabetes status (3 vs. 0; P = 0.08) between transplant patients and controls. No difference existed in vascular markers between patients and controls at baseline. In transplant patients, FMD decreased (− 1.52 ± 2.74; P = 0.03), cf-PWV increased (0.62 ± 1.06; P = 0.03), and CCA-IMT increased (0.35 ± 0.53; P = 0.02). No changes were observed in controls.

Conclusion

Markers of vascular structure and function worsen in the post-transplant period on long-term follow-up, which may explain the continued high cardiovascular event rates in this population.

Late Conversion From Calcineurin Inhibitors to Belatacept in Kidney-Transplant Recipients Has a Significant Beneficial Impact on Glycemic Parameters

Background.

Calcineurin inhibitors (CNIs) and steroids are strongly associated with new-onset diabetes after transplantation, worsening of pre-existing diabetes, and cardiovascular events. We assessed the benefit of conversion from CNI-based to belatacept-based immunosuppression in diabetic kidney-transplant (KT) recipients on glucose control and cardiovascular risk factors.

Methods.

In this retrospective, noncontrolled single-study conducted between May 2016 and October 26, 2018, we recruited KT recipients converted from CNIs to belatacept at least 6 months after KT. The primary endpoint was the evolution of hemoglobin A1c (HbA1c) between baseline and after 6 months of treatment. Secondary endpoints included modifications to antidiabetic drugs, other cardiovascular risk factors, and renal function.

Results.

One hundred and three KT recipients were included. Of these, 26 (25%) had type 2 diabetes. The patients were either receiving oral antidiabetic drugs (n = 21; 75%) or insulin therapy (n = 14; 54%). Overall HbA1c decreased significantly from 6.2 ± 1 to 5.8 ± 1%, P < 0.001. In diabetic patients, HbA1c decreased from 7.2 ± 1 to 6.5 ± 1%, P = 0.001. HbA1c significantly decreased in the subgroup of patients with new-onset diabetes after transplantation and whether diabetes was controlled at inclusion or not (ie, HA1c ≤7% or >7%). Moreover, no diabetic patient increased the number of oral antidiabetic drugs and the dose of basal insulin was not statistically different from baseline to 6 months (16 international unit at baseline and 16 international unit at 6 mo, P = 1). One patient had to start treatment by insulin pump. During follow-up, the renal function, body mass index, and hemoglobin level of all 103 patients remained stable, 2 patients presented acute cellular rejection, and no patient suffered from graft loss.

Conclusions.

A late switch from CNI to belatacept was a valuable therapeutic option for diabetic kidney recipients and substantially improved glycemic parameters.

Efficacy and Safety of Belatacept Treatment in Renal Allograft Recipients at High Cardiovascular Risk-A Single Center Experience

Belatacept is an attractive option for immunosuppression after renal transplantation. Renal allograft function is superior when compared to calcineurin inhibitor (CNI) based therapy in “de novo” treated patients and it has also been proposed that individuals at high cardiovascular (CV) risk may benefit most. In this retrospective cohort study, we assessed the efficacy and safety of treating patients at high cardiovascular risk with Belatacept (n = 34, for 1194 observation months) when compared to a matched control group of 150 individuals under CNI immunosuppression (for 7309 months of observation). The estimated glomerular filtration rate (eGFR) increased for patients taking Belatacept but decreased during CNI-based therapy (+2.60 vs. −0.89 mL/min/1.73 m²/year, p = 0.006). In a multivariate Cox regression model, Belatacept remained the only significant factor associated with the improvement of eGFR (HR 4.35, 95%CI 2.39–7.93). Belatacept treatment was not a significant risk factor for renal allograft rejection or graft loss. In terms of safety, the only significant risk factor for de novo cardiovascular events was a pre-existing cerebrovascular disease, but Belatacept was not associated with a significant risk reduction. Belatacept treatment was not associated with an increased risk of severe infections, cytomegalo virus (CMV) or BK-virus reactivation, malignancy or death in the multivariate Cox regression analysis. Belatacept is an efficient and safe option for patients after renal transplantation at high cardiovascular risk.

Hypertension: a new treatment for an old disease? Targeting the immune system

Arterial hypertension represents a serious public health problem, being a major cause of morbidity and mortality worldwide. The availability of many antihypertensive therapeutic strategies still fails to adequately treat around 20% of hypertensive patients, who are considered resistant to conventional treatment. In the pathogenesis of hypertension, immune system mechanisms are activated and both the innate and adaptive immune responses play a crucial role. However, what, when and how the immune system is triggered during hypertension development is still largely undefined. In this context, this review highlights scientific advances in the manipulation of the immune system in order to attenuate hypertension and end-organ damage. Here, we discuss the potential use of immunosuppressants and immunomodulators as pharmacological tools to control the activation of the immune system, by non-specific and specific mechanisms, to treat hypertension and improve end-organ damage. Nevertheless, more clinical trials should be performed with these drugs to establish their therapeutic efficacy, safety and risk-benefit ratio in hypertensive conditions. LINKED ARTICLES: This article is part of a themed section on Immune Targets in Hypertension. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.12/issuetoc.

Arterial Stiffness in the Heart Disease of CKD

CKD frequently leads to chronic cardiac dysfunction. This complex relationship has been termed as cardiorenal syndrome type 4 or cardio-renal link. Despite numerous studies and reviews focused on the pathophysiology and therapy of this syndrome, the role of arterial stiffness has been frequently overlooked. In this regard, several pathogenic factors, including uremic toxins (i.e., uric acid, phosphates, endothelin-1, advanced glycation end-products, and asymmetric dimethylarginine), can be involved. Their effect on the arterial wall, direct or mediated by chronic inflammation and oxidative stress, results in arterial stiffening and decreased vascular compliance. The increase in aortic stiffness results in increased cardiac workload and reduced coronary artery perfusion pressure that, in turn, may lead to microvascular cardiac ischemia. Conversely, reduced arterial stiffness has been associated with increased survival. Several approaches can be considered to reduce vascular stiffness and improve vascular function in patients with CKD. This review primarily discusses current understanding of the mechanisms concerning uremic toxins, arterial stiffening, and impaired cardiac function, and the therapeutic options to reduce arterial stiffness in patients with CKD.

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.

Belatacept prophylaxis against organ rejection in adult kidney-transplant recipients

End-stage renal disease is a major health problem worldwide, with kidney transplantation being the treatment of choice. Calcineurin inhibitors are still the cornerstone of immunosuppressive therapy. However, they have well-known nephrotoxic affects and increase the risk of cardiovascular disease and cancer. In contrast, belatacept is a biological immunosuppressive agent that inhibits the T-cell co-stimulation. It is approved by the US Food and Drug Administration and the European Medicine Agency for use in adult kidney-transplant recipients to prevent acute rejection. Developmental studies show that belatacept is as efficient as calcineurin inhibitors at preventing acute rejection. In addition, kidney function is better and cardiovascular risk factors are reduced in patients given belatacept. Herein, the authors review the published evidence concerning the efficacy and safety of belatacept and discuss its potential specific indications.

Similarities in coronary function and myocardial deformation between psoriasis and coronary artery disease: the role of oxidative stress and inflammation

BACKGROUND

Psoriasis has been associated with increased risk for coronary artery disease (CAD). We investigated the presence of vascular and subclinical left ventricular (LV) dysfunction in patients with psoriasis compared with patients with CAD.

METHODS

We compared 59 patients with psoriasis without evidence of CAD (psoriasis area and severity index [PASI], 11.5 ± 8) with 59 patients with angiographically documented CAD and 40 controls. We measured (1) the carotid-femoral pulse wave velocity (PWVc) and central augmentation index (CAI), (2) coronary flow reserve (CFR) by Doppler echocardiography, (3) flow-mediated dilation (FMD) of the brachial artery and carotid intima media thickness (IMT), (4) LV global longitudinal strain (GLS) and GLS rate (GLSR) using speckle tracking echocardiography, and (5) malondialdehyde (MDA) and interleukin-6 (IL-6) levels.

RESULTS

Patients with psoriasis had higher PWVc, CAI, IMT, MDA, and IL-6 levels and lower FMD, CFR, GLS, and GLSR than did controls (P < 0.05), but they had values of these markers that were similar to those of patients with CAD (P > 0.05) after adjustment for atherosclerotic risk factors: (PWVc [m/s], 10.4 ± 1.8 vs 8.6 ± 1.5 vs 10.3 ± 2, respectively; CFR, 2.4 ± 0.1 vs 3.4 ± 0.6 vs 2.6 ± 0.6, respectively; GLS [%], -16.2 ± 4 vs -21.9 ± 1.6 vs -16.6 ± 4.5, respectively; GLSR [L/sec], -0.85 ± 0.2 vs -1.2 ± 0.12 vs -0.9 ± 0.4, respectively; MDA [nM/L], 1.68 vs 1.76 vs 1.01, respectively; IL-6 [pg/mL], 2.26 vs 2.2 vs 1.7, respectively; P < 0.05 for all comparisons). PASI was related to IMT (r = 0.67; P < 0.01). Decreased GLS was associated with increased MDA, IL-6, PWVc, CAI, and reduced CFR (P < 0.05).

CONCLUSIONS

Psoriasis and CAD present similar vascular and LV myocardial dysfunction, possibly because of similar underlying inflammatory and oxidative stress processes. Vascular dysfunction in psoriasis is linked to abnormal LV myocardial deformation.