Causes of death in patients with chronic kidney disease: insights from the ASCEND-D and ASCEND-ND cardiovascular outcomes trials

Background

There are limited contemporary data available regarding adjudicated causes of death in patients with chronic kidney disease (CKD). Prior studies have indicated that cardiovascular (CV) events are one of the most common causes of death among patients with CKD, with previous reports stating approximately 30% of patients died from CV causes [1]. Here, we report the adjudicated causes of death in two recently completed large-scale randomised controlled trials (RCTs) with ∼14,200 person years of follow-up: ASCEND-D [2] (median follow-up: 2.5 years; NCT02879305) and ASCEND-ND [3] (median follow-up: 1.9 years; NCT02876835). These trials investigated the safety and efficacy of daprodustat, a hypoxia-inducible factor prolyl hydroxylase inhibitor (HIF-PHI), in correcting anaemia in patients with CKD.

Purpose

This study assessed the causes of death in patients with CKD in the ASCEND-D and ASCEND-ND trials.

Methods

ASCEND-D and ASCEND-ND were global, randomised, open-label, CV outcome trials in adult patients with CKD-related anaemia undergoing maintenance dialysis (ASCEND-D) or with pre-dialysis CKD (ASCEND-ND) who received daily oral daprodustat or conventional erythropoiesis-stimulating agents (ESAs). Cause of death was systematically and centrally adjudicated in a blinded fashion to the study treatment assignment by an independent committee.

Results

In ASCEND-D and ASCEND-ND, respectively, 2964 and 3872 patients were randomised, of which 92% and 97% completed the study. Baseline characteristics were well-balanced across treatment groups within each trial. Adjudicated causes of death for the ASCEND-D and -ND trials are shown in the Table. All-cause mortality was similar in patients treated with daprodustat as compared with those treated with conventional ESA in both the ASCEND-D and -ND trials. Overall mortality in the ASCEND-D and -ND trials was 20.0% and 15.5%, respectively, and CV causes accounted for approximately 30–40% of all deaths and infection accounted for 25–30% of all deaths in both trials.

Conclusion

Although CV events were the most common cause of death in the ASCEND-D and ASCEND-ND trials (30–40% of cases), the risk of death due to infection was also high, accounting for approximately 25–30% of all deaths across all study arms. Sudden death accounted for most CV deaths, particularly in the ASCEND-D trial. Infection as a cause of death was more frequent than previously reported in other RCTs or disease registries. Causes of death did not differ significantly between ASCEND-D and ASCEND-ND, or between treatments. However, as this is a selected population for a CV trial, it may not be representative of a real-life CKD population. Our results provide important data to inform the design of future studies in this population.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): This study was funded by GlaxoSmithKline. Medical writing support was provided Natasha Tracey, PhD (Ashfield MedComms, Macclesfield, UK) and was funded by GlaxoSmithKline.

Randomized trial of tacrolimus plus mycophenolate mofetil or azathioprine versus cyclosporine oral solution (modified) plus mycophenolate mofetil after cadaveric kidney transplantation: results at 2 years

BACKGROUND

A previous report described the 1-year results of a prospective, randomized trial designed to investigate the optimal combination of immunosuppressants in kidney transplantation. Recipients of first cadaveric kidney allografts were treated with tacrolimus+mycophenolate mofetil (MMF), cyclosporine oral solution (modified) (CsA)+MMF, or tacrolimus+azathioprine (AZA). Results at 1 year revealed that optimal efficacy and safety were achieved with a regimen containing tacrolimus+MMF. The present report describes results at 2 years.

METHODS

Two hundred twenty-three recipients of first cadaveric kidney allografts were randomized to receive tacrolimus+MMF, CsA+MMF, or tacrolimus+AZA. All regimens contained corticosteroids, and antibody induction was used only in patients who experienced delayed graft function. Patients were followed up for 2 years.

RESULTS

The results at 2 years corroborate and extend the findings of the previous report. Patients randomized to either treatment arm containing tacrolimus experienced improved kidney function. New-onset insulin dependence remained in four, three, and four patients in the tacrolimus+MMF, CsA+MMF, and tacrolimus+AZA treatment arms, respectively. Furthermore, patients with delayed graft function/acute tubular necrosis who were treated with tacrolimus+MMF experienced a 23% increase in allograft survival compared with patients receiving CsA+MMF (P=0.06). Patients randomized to tacrolimus+MMF received significantly lower doses of MMF compared with those administered CsA+MMF.

CONCLUSIONS

All three immunosuppressive regi-mens provided excellent safety and efficacy. How-ever, the best results overall were achieved with tacrolimus+MMF. The combination may provide particular benefit to kidney allograft recipients who develop delayed graft function/acute tubular necrosis. Renal function at 2 years was better in the tacrolimus treatment groups compared with the CsA group.

Randomized trial of tacrolimus (Prograf) in combination with azathioprine or mycophenolate mofetil versus cyclosporine (Neoral) with mycophenolate mofetil after cadaveric kidney transplantation

BACKGROUND

Our clinical trial was designed to investigate the optimal combination of immunosuppressants for renal transplantation.

METHODS

A randomized three-arm, parallel group, open label, prospective study was performed at 15 North American centers to compare three immunosuppressive regimens: tacrolimus + azathioprine (AZA) versus cyclosporine (Neoral) + mycophenolate mofetil (MMF) versus tacrolimus + MMF. All patients were first cadaveric kidney transplants receiving the same maintenance corticosteroid regimen. Only patients with delayed graft function (32%) received antilymphocyte induction. A total of 223 patients were randomized, transplanted, and followed for 1 year.

RESULTS

There were no significant differences in baseline demography between the three treatment groups. At 1 year the results are as follows: acute rejection 17% (95% confidence interval 9%, 26%) in tacrolimus + AZA; 20% (confidence interval 11%, 29%) in cyclosporine + MMF; and 15% (confidence interval 7%, 24%) in tacrolimus + MMF. The incidence of steroid resistant rejection requiring antilymphocyte therapy was 12% in the tacrolimus + AZA group, 11% in the cyclosporine + MMF group, and 4% in the tacrolimus + MMF group. There were no significant differences in overall patient or graft survival. Tacrolimus-treated patients had a lower incidence of hyperlipidemia through 6 months posttransplant. The incidence of posttransplant diabetes mellitus requiring insulin was 14% in the tacrolimus + AZA group, 7% in the cyclosporine + MMF and 7% in the tacrolimus + MMF groups.

CONCLUSIONS

All regimens yielded similar acute rejection rates and graft survival, but the tacrolimus + MMF regimen was associated with the lowest rate of steroid resistant rejection requiring antilymphocyte therapy.

Cyclosporine, but not FK506, selectively induces renal and coronary artery smooth muscle contraction

BACKGROUND

Cyclosporine immunosuppression for organ transplantation is associated with hypertension and nephrotoxicity. Because the effects of cyclosporine as an immunosuppressant are mediated by the effect of cyclosporine as a phosphatase inhibitor, and phosphatase inhibitors are potent vascular smooth muscle contractile agents, we hypothesized that cyclosporine might induce contraction of the renal artery vascular smooth muscle directly.

METHODS

Strips of bovine renal, carotid, superior mesenteric, or coronary arteries were obtained fresh from an abattoir. The strips were equilibrated in a muscle bath, and the contractile responses to cyclosporine and FK506 were determined.

RESULTS

Cyclosporine (50 to 5000 micrograms/ml), but not FK506, induced rapidly developing, sustained contractions of renal and coronary artery smooth muscle. The magnitude of the cyclosporine-induced contractions of carotid and superior mesenteric artery smooth muscles was significantly less. The magnitude of renal artery smooth muscle contractions induced by cyclosporine was enhanced in the presence of an intact endothelium.

CONCLUSIONS

Although these effects occurred in vitro to relatively high doses of cyclosporine, these data suggest that cyclosporine may selectively induce renal artery smooth muscle contraction through activation of the Ca(2+)-dependent phosphatase (calcineurin) in the smooth muscle, and these contractions may be enhanced by the release of endothelial-derived contracting factors.

Cyclosporine, but not FK506, selectively induces renal and coronary artery smooth muscle contraction

BACKGROUND

Cyclosporine immunosuppression for organ transplantation is associated with hypertension and nephrotoxicity. Because the effects of cyclosporine as an immunosuppressant are mediated by the effect of cyclosporine as a phosphatase inhibitor, and phosphatase inhibitors are potent vascular smooth muscle contractile agents, we hypothesized that cyclosporine might induce contraction of the renal artery vascular smooth muscle directly.

METHODS

Strips of bovine renal, carotid, superior mesenteric, or coronary arteries were obtained fresh from an abattoir. The strips were equilibrated in a muscle bath, and the contractile responses to cyclosporine and FK506 were determined.

RESULTS

Cyclosporine (50 to 5000 micrograms/ml), but not FK506, induced rapidly developing, sustained contractions of renal and coronary artery smooth muscle. The magnitude of the cyclosporine-induced contractions of carotid and superior mesenteric artery smooth muscles was significantly less. The magnitude of renal artery smooth muscle contractions induced by cyclosporine was enhanced in the presence of an intact endothelium.

CONCLUSIONS

Although these effects occurred in vitro to relatively high doses of cyclosporine, these data suggest that cyclosporine may selectively induce renal artery smooth muscle contraction through activation of the Ca(2+)-dependent phosphatase (calcineurin) in the smooth muscle, and these contractions may be enhanced by the release of endothelial-derived contracting factors.

Effects of tacrolimus on hyperlipidemia after successful renal transplantation: a Southeastern Organ Procurement Foundation multicenter clinical study

BACKGROUND

Tacrolimus has been shown to have a less adverse effect on the lipid profiles of transplant patients when the drug is started as induction therapy. In order to determine the effect tacrolimus has on lipid profiles in stable cyclosporine-treated renal transplant patients with established hyperlipidemia, a randomized prospective study was undertaken by the Southeastern Organ Procurement Foundation.

METHODS

Patients of the 13 transplant centers, with cholesterol of 240 mg/dl or greater, who were at least 1 year posttransplant with stable renal function, were randomly assigned to remain on cyclosporine (control) or converted to tacrolimus. Patients converted to tacrolimus were maintained at a level of 5-15 ng/ml, and control patients remained at their previous levels of cyclosporine. Concurrent immunosuppressants were not changed. Levels of total cholesterol, triglycerides, total high-density lipoprotein, low-density lipoprotein (LDL), very-low-density lipoprotein, and apoproteins A and B were monitored before conversion and at months 1, 3, and 6. Renal function and glucose control were evaluated at the beginning and end of the study (month 6).

RESULTS

A total of 65 patients were enrolled; 12 patients failed to complete the study. None were removed as a result of acute rejection or graft failure. Fifty-three patients were available for analysis (27 in the tacrolimus group and 26 controls). Demographics were not different between groups. In patients converted to tacrolimus treatment, there was a -55 mg/dl (-16%) (P=0.0031) change in cholesterol, a -48 mg/dl (-25%) (P=0.0014) change in LDL cholesterol, and a -36 mg/dl (-23%) (P=0.034) change in apolipoprotein B. There was no change in renal function, glycemic control, or incidence of new onset diabetes mellitus in the tacrolimus group.

CONCLUSION

Conversion from cyclosporine to tacrolimus can be safely done after successful transplantation. Introduction of tacrolimus to a stable renal patient does not effect renal function or glycemic control. Tacrolimus can lower cholesterol, LDL, and apolipoprotein B. Conversion to tacrolimus from cyclosporine should be considered in the treatment of posttransplant hyperlipidemia.