Immunosuppressive Therapy for Elderly Kidney Transplant Recipients. Transplant Proc. 2016;48:799-801. [PMID: 27234739 DOI: 10.1016/j.transproceed.2016.02.039]

Exposure to tacrolimus trough levels below 6 ng/ml during the first year is associated with inferior kidney graft survival

BACKGROUND

Accumulating data indicate that sub-therapeutic levels of tacrolimus are associated with long-term kidney graft loss. However, elevated doses increase the risk of infection and drug toxicity, which also threaten graft and patient longevity. We sought to determine the minimal tacrolimus level required to maintain graft survival.

METHODS

We conducted a single-center historical cohort study. The first-year post-transplant exposure time was calculated for each of the five tacrolimus trough level intervals. This measure was adjusted to the exposure time below a given interval level, allowing us to define the threshold for the optimal tacrolimus level as the upper limit of the interval. We then determined the association between the adjusted exposure time at each tacrolimus level interval and our primary outcome, death-censored graft loss.

RESULTS

One thousand four hundred and seventeen patients with a median follow-up of 5.3 years were included in the final cohort. The tacrolimus level interval of 5-6 ng/ml was the highest interval, which demonstrated a statistically significant association between adjusted exposure time and increased risk of graft loss (HR 1.58, per log days, p = .002). Cumulative exposure time above 14 days with a tacrolimus level below 6 ng/ml was associated with an increased rate of graft loss in most studied subgroups, except for recipients with pre transplant diabetes.

CONCLUSIONS

Maintaining tacrolimus levels above 6 ng/ml during the first-year post-transplant might improve kidney graft survival.

Does steroid-free immunosuppression improve the outcome in kidney transplant recipients compared to conventional protocols?

Steroids continue to be the cornerstone of immune suppression since the early days of organ transplantation. Steroids are key component of induction protocols, maintenance therapy and in the treatment of various forms of rejection. Prolonged steroid use resulted in significant side effects on almost all the body organs owing to the presence of steroid receptors in most of the mammalian cells. Kidney allograft recipients had to accept the short and long term complications of steroids because of lack of effective alternatives. This situation changed with the intro-duction of newer and more effective immune suppression agents with a relatively more acceptable side effect profile. As a result, the clinicians have been contemplating if it is the time to abandon the unquestionable reliance on maintenance steroids in modern transplantation practice. This review aims to evaluate the safety and efficacy of various steroid-minimization approaches (steroid avoidance, early steroid withdrawal, and late steroid withdrawal) in kidney transplant recipients. A meticulous electronic search was conducted through the available data resources like SCOPUS, MEDLINE, and Liverpool University library e-resources. Relevant articles obtained through our search were included. A total number of 90 articles were eligible to be included in this review [34 randomised controlled trials (RCT) and 56 articles of other research modalities]. All articles were evaluating the safety and efficacy of various steroid-free approaches in comparison to maintenance steroids. We will cover only the RCT articles in this review. If used in right clinical context, steroid-free protocols proved to be comparable to steroid-based maintenance therapy. The appropriate approach should be tailored individually according to each recipient immuno-logical challenges and clinical condition.

Infection-Related Mortality in Recipients of a Kidney Transplant in Australia and New Zealand

BACKGROUND AND OBJECTIVES

The burden of infectious disease is high among kidney transplant recipients because of concomitant immunosuppression. In this study the incidence of infectious-related mortality and associated factors were evaluated.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

In this registry-based retrospective, longitudinal cohort study, recipients of a first kidney transplant in Australia and New Zealand between 1997 and 2015 were included. Cumulative incidence of infectious-related mortality was estimated using competing risk regression (using noninfectious mortality as a competing risk event), and compared with age-matched, populated-based data using standardized incidence ratios.

RESULTS

Among 12,519 patients, (median age 46 years, 63% men, 15% diabetic, 6% Indigenous ethnicity), 2197 (18%) died, of whom 416 (19%) died from infection. The incidence of infection-related mortality during the study period (1997-2015) was 45.8 (95% confidence interval [95% CI], 41.6 to 50.4) per 10,000 patient-years. The incidence of infection-related mortality reduced from 53.1 (95% CI, 45.0 to 62.5) per 10,000 person-years in 1997-2000 to 43.9 (95% CI, 32.5 to 59.1) per 10,000 person-years in 2011-2015 (P<0.001) Compared with the age-matched general population, kidney transplant recipients had a markedly higher risk of infectious-related death (standardized incidence ratio, 7.8; 95% CI, 7.1 to 8.6). Infectious mortality was associated with older age (≥60 years adjusted subdistribution hazard ratio [SHR], 4.16; 95% CI, 2.15 to 8.05; reference 20-30 years), female sex (SHR, 1.62; 95% CI, 1.19 to 2.29), Indigenous ethnicity (SHR, 2.87; 95% CI, 1.84 to 4.46; reference white), earlier transplant era (2011-2015: SHR, 0.39; 95% CI, 0.20 to 0.76; reference 1997-2000), and use of T cell-depleting therapy (SHR, 2.43; 95% CI, 1.36 to 4.33). Live donor transplantation was associated with lower risk of infection-related mortality (SHR, 0.53; 95% CI, 0.37 to 0.76).

CONCLUSIONS

Infection-related mortality in kidney transplant recipients is significantly higher than the general population, but has reduced over time. Risk factors include older age, female sex, Indigenous ethnicity, T cell-depleting therapy, and deceased donor transplantation.

PODCAST

This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2019_08_27_CJN03200319.mp3.

Alemtuzumab Induction Is Associated With Equalization of Graft Outcomes Between Elderly and Nonelderly Kidney Transplant Recipients: A Single-Center Report

OBJECTIVES

Alemtuzumab (monoclonal anti-CD52 antibody) provides profound lymphocyte depletion and offers numerous advantages as an induction agent. Elderly recipients (> 65 years old) traditionally have inferior posttransplant outcomes versus younger recipients. We investigated short-term and long-term patient and graft survival rates following alemtuzumab induction in elderly recipients.

MATERIALS AND METHODS

This retrospective analysis, which included 676 renal allograft transplant recipients with alemtuzumab induction, was conducted at the University of Toledo Medical Center between March 2006 and November 2015. We used 2-sided t test, Pearson chi-square test, Fisher exact test, and Cox proportional hazard regressions with 95% confidence interval for analyses. P < .05 was significant.

RESULTS

Elderly recipients were more likely to receive a kidney from an inferior donor (deceased donor: 82% vs 72.4%; P = .030) and have higher mean kidney donor profile index (46.2 vs 38.4; P = .024) than nonelderly recipients. Elderly recipients were more likely to experience delayed graft function (15.1% vs 8.5%; P = .038). Elderly recipients demonstrated death-censored graft survival (1 year: 95.4% vs 93.1%; 3 years: 88.5% vs 93.3%; 5 years: 83.1% vs 86.4%) and rejection rates (1 year: 19.8% vs 21.2%; 3 years: 22.1% vs 25.3%; 5 years: 23.8% vs 26.9%) similar to nonelderly recipients. Elderly recipients had significantly higher overall mortality rates than recipients under 65 years old (29.8% vs. 13.2%; P = .001). Although 1-year patient survival was similar to younger recipients (94.8% vs 96.3%; P = .431), 3-year (80.0% vs 91.5%; P = .006) and 5-year (72.9% vs 86.2%; P = .19) rates were significantly decreased in elderly recipients.

CONCLUSIONS

Elderly age is not a predictor of rejection or death-censored graft loss in individuals who receive alemtuzumab induction. Despite elevated overall mortality, elderly recipients induced with alemtuzumab demonstrated rejection, graft, and short-term patient survival rates similar to younger recipients.

Effect of Age on Leukopenia Following Renal Transplantation at a Single Center

Introduction:

Leukopenia in renal transplant recipients occurs commonly within the first year following transplantation; however, literature on the effects of age on leukopenia is scarce.

Design:

A single-center, retrospective review was conducted on 141 recipients transplanted from January 2011 to December 2015. Transplant recipients were characterized by age <60 years (n = 94) or age 60 years and older (n = 47) for analysis.

Results:

A greater incidence of leukopenia was seen in the older cohort compared to the younger cohort (64% vs 55%). Of those patients who developed leukopenia, the older cohort (n = 30) had a higher incidence of hospitalization for leukopenia (30% vs 23%) but a lower incidence of hospitalization for infection (20% vs 25%) compared to the younger cohort (n = 52). Additionally, one month following mycophenolate mofetil (MMF) discontinuation, the older cohort had reduced recovery of their white blood cell count (+263.8% vs +272.5%) and experienced less recurrent leukopenic episodes (50% vs 67%) and rejection episodes (0% vs 22%) compared to the younger cohort, alluding to the need for less immunosuppression.

Conclusions:

Age at transplantation was not associated with the development of leukopenia; however, older patients had a higher incidence of leukopenia and hospitalization for leukopenia. Dose reduction or discontinuation of MMF should be considered in older kidney transplant recipients who develop leukopenia.