Allocation strategies for elderly kidney transplant recipients

Kidney donor age of 50 years or above is a risk factor for calcineurin inhibitor-induced nephrotoxicity

INTRODUCTION

Calcineurin inhibitor (CNI)-induced nephrotoxicity (CNI-T) is a post-transplantation complication that leads to graft dysfunction. Older-donor kidney grafts may be susceptible to chronic CNI exposure because of long-term arteriolar damage. The primary aim of this study was to examine the CNI-T incidence and time-course changes in the graft function according to donor age.

METHODS

We included 334 kidney transplant recipients. CNI-T was defined by Banff arteriolar hyaline thickening scores of ≥2 based on allograft protocol biopsy. Depending on donor age, participants were divided into the D > 70 (≥70 years), D60 (60-69 years), D50 (50-59 years), and D < 49: (≤49 years) groups. We investigated the extent to which CNI-T affected the transplanted kidney function. Patients who did not develop CNI-T during the study period were included in the non-CNI-T group; the remaining were grouped into the CNI-T group.

RESULTS

The CNI-T incidence was higher in donors aged >50 years. Compared to D < 49, the CNI-T risk was 1.86 times higher in D50 and 2.9 times higher in D > 70. Furthermore, the CNI-T group exhibited a significantly lower graft function 10 years after transplantation.

CONCLUSION

CNI-T incidence increases in donors aged ≥50 years and affects renal function after 10 years.

[Focusing on kidney transplantation in the elderly]

Due to the increase in life expectancy and the ageing of end-stage renal disease patients, the number of patients older than 65 years receiving a kidney transplant has been continuously growing over the last fifteen years. The benefits of renal transplantation compared to dialysis in terms of survival and quality of life have been shown in selected recipients over 65, or 70 years. However, the age remains the main limiting factor for the access to the waiting list, and the reluctance of the clinicians can be explained by the multiple comorbidities of these candidates, their limited life expectancy or the shortage of grafts. The challenge is to select the candidates who can benefit from renal transplantation, thanks to rigorous cardiovascular and neoplastic evaluation before enrolment and by taking into account the specific characteristics of elderly patients. The living donor appears to be the ideal option for elderly recipients, the alternative being the extended criteria donor, allowing waiting times to be limited. The choice of immunosuppressive therapy is also crucial in these patients at high risk of infectious and cardiovascular complications in whom the occurrence of acute rejection can have severe consequences. There are currently no specific recommendations for immunosuppression in elderly recipients, and we would need large-scale randomized studies to improve the prognosis of renal transplantation in this population.