Negative impact of underlying non-insulin-dependent diabetes mellitus nephropathy on long-term allograft survival in kidney transplantation: a 10-year analysis from a single center

Effect of Mammalian Target of Rapamycin Inhibition on Activated Regulatory T-Cell Expansion in Kidney Transplantation

BACKGROUND

The mammalian target of rapamycin (mTOR) plays a critical role in the host immune response in organ transplantation. This study evaluates the regulatory benefits of mTOR inhibitors in kidney transplant recipients (KTRs).

METHODS

The mTOR-dependent immune-regulating effects in KTRs were evaluated by examining T-cell subsets among peripheral blood mononuclear cells from 79 KTRs. Recipients included an early introduction of everolimus (EVR) and reduced-exposure tacrolimus group (n = 46) and a standard tacrolimus-based without EVR (non-EVR) group (n = 33).

RESULTS

Trough concentrations of tacrolimus at 3 months and 1 year were significantly lower in the EVR group than the non-EVR group (both P < .001). In addition, the respective proportions of patients without estimated glomerular filtration rate < 20% in the EVR and non-EVR groups were 100% and 93.3% at 1 year, 96.3% and 89.7% at 2 years, and 96.3% and 89.7% at 3 years after blood collection, respectively (P = .079). The frequencies of CD3⁺ T cells and CD4⁺ T cells among peripheral blood mononuclear cells were comparable between groups. Total CD25^highCD127^-CD4⁺ regulatory T (Treg) cells were similar in the EVR and non-EVR groups. In contrast, circulating CD45RA^-CD25^highCD127^-CD4⁺ activated Treg cells were significantly higher in the EVR group (P= .008).

CONCLUSION

These results suggest that the early introduction of mTOR benefits long-term kidney graft function and circulating activated Treg-cell expansion in KTRs.

The Efficacy and Safety of SGLT2 Inhibitor in Diabetic Kidney Transplant Recipients

BACKGROUND

The efficacy and safety of sodium-glucose cotransporter 2 inhibitors (SGLT2i) have not been investigated in kidney transplant recipients (KTRs) with diabetes. We evaluated the impact of SGLT2i in a multicenter cohort of diabetic KTRs.

METHODS

A total of 2083 KTRs with diabetes were enrolled from 6 transplant centers in Korea. Among them, 226 (10.8%) patients were prescribed SGLT2i for >90 d. The primary outcome was a composite outcome of all-cause mortality, death-censored graft failure (DCGF), and serum creatinine doubling. An acute dip in estimated glomerular filtration rate (eGFR) over 10% was surveyed after SGLT2i use.

RESULTS

During the mean follow-up of 62.9 ± 42.2 mo, the SGLT2i group had a lower risk of primary composite outcome than the control group in the multivariate and propensity score-matched models (adjusted hazard ratio, 0.43; 95% confidence interval, 0.24-0.78; P = 0.006 and adjusted hazard ratio, 0.45; 95% confidence interval, 0.24-0.85; P = 0.013, respectively). Multivariate analyses consistently showed a decreased risk of DCGF and serum creatinine doubling in the SGLT2i group. The overall eGFR remained stable without the initial dip after SGLT2i use. A minority (15.6%) of the SGLT2i users showed acute eGFR dip during the first month, but the eGFR recovered thereafter. The risk factors for the eGFR dip were time from transplantation to SGLT2i usage and mean tacrolimus trough level.

CONCLUSIONS

SGLT2i improved a composite of all-cause mortality, DCGF, or serum creatinine doubling in KTRs. SGLT2i can be used safely and have beneficial effects on preserving graft function in diabetic KTRs.

Use of Sodium-Glucose Cotransporter-2 Inhibitors in Renal Transplant Patients With Diabetes: A Brief Review of the Current Literature

Sodium-glucose cotransporter-2 (SGLT2) inhibitors are a novel class of oral hypoglycemic agents commonly prescribed in type 2 diabetes (T2D). They have been shown to slow the progression of diabetic nephropathy and improve cardiovascular outcomes in high-risk individuals, although major cardiovascular and renal outcome clinical trials have excluded renal transplant patients. The aim of this review was to determine the outcomes and safety with use of SGLT2 inhibitors in renal transplant patients with diabetes. We conducted a review of randomized controlled trials, cohort studies, case series and case reports that assessed use of SGLT2 inhibitors in patients post-renal transplant with either pre-existing T2D or new-onset diabetes after transplant. The outcomes assessed included blood pressure, renal allograft function (estimated glomerular filtration rate), proteinuria (urinary albumin-to-creatinine ratio), glycemic control, body weight and adverse effects. A total of 9 studies, which included 144 patients, were reviewed. SGLT2 inhibitor use in renal transplant patients demonstrates either a small or nonsignificant reduction in blood pressure and results in overall stable renal allograft function. It also results in modest improvement in glycemic control as well as weight reduction. The incidence of adverse effects is low and reversible, as reported in previous nontransplant clinical trials. Overall, our findings suggest beneficial outcomes with no significant adverse effects or complications with the use of SGLT2 inhibitors in renal transplant patients with diabetes; however, these findings are based on small trials, and thus well-designed trials in this population are warranted.

Determinants of Poor Glycemic Control in Patients with Kidney Transplants: A Single-Center Retrospective Cohort Study in Canada

Background:

Kidney transplant immunosuppressive medications are known to impair glucose metabolism, causing worsened glycemic control in patients with pre-transplant diabetes mellitus (PrTDM) and new onset of diabetes after transplant (NODAT).

Objectives:

To determine the incidence, risk factors, and outcomes of both PrTDM and NODAT patients.

Design:

This is a single-center retrospective observational cohort study.

Setting:

The Ottawa Hospital, Ontario, Canada.

Participant:

A total of 132 adult (>18 years) kidney transplant patients from 2013 to 2015 were retrospectively followed 3 years post-transplant.

Measurements:

Patient characteristics, transplant information, pre- and post-transplant HbA1C and random glucose, follow-up appointments, complications, and readmissions.

Methods:

We looked at the prevalence of poor glycemic control (HbA1c >8.5%) in the PrTDM group before and after transplant and compared the prevalence, follow-up appointments, and rate of complications and readmission rates in both the PrTDM and NODAT groups. We determined the risk factors of developing poor glycemic control in PrTDM patients and NODAT. Student t-test was used to compare means, chi-squared test was used to compare percentages, and univariate analysis to determine risk factors was performed by logistical regression.

Results:

A total of 42 patients (31.8%) had PrTDM and 12 patients (13.3%) developed NODAT. Poor glycemic control (HbA1c >8.5%) was more prevalent in the PrTDM (76.4%) patients compared to those with NODAT (16.7%; P < .01). PrTDM patients were more likely to receive follow-up with an endocrinologist (P < .01) and diabetes nurse (P < .01) compared to those with NODAT. There were no differences in the complication and readmission rates for PrTDM and NODAT patients. Receiving a transplant from a deceased donor was associated with having poor glycemic control, odds ratio (OR) = 3.34, confidence interval (CI = 1.08, 10.4), P = .04. Both patient age, OR = 1.07, CI (1.02, 1.3), P < .01, and peritoneal dialysis prior to transplant, OR = 4.57, CI (1.28, 16.3), P = .02, were associated with NODAT.

Limitations:

Our study was limited by our small sample size. We also could not account for any diabetes screening performed outside of our center or follow-up appointments with family physicians or community endocrinologists.

Conclusion:

Poor glycemic control is common in the kidney transplant population. Glycemic targets for patients with PrTDM are not being met in our center and our study highlights the gap in the literature focusing on the prevalence and outcomes of poor glycemic control in these patients. Closer follow-up and attention may be needed for those who are at risk for worse glycemic control, which include older patients, those who received a deceased donor kidney, and/or prior peritoneal dialysis.

Outcomes of living donor kidney transplantation in diabetic patients: age and sex matched comparison with non-diabetic patients

BACKGROUND/AIMS

Kidney transplantation (KT) reportedly provides a significant survival advantage over dialysis in diabetic patients. However, KT outcome in diabetic patients compared with that in non-diabetic patients remains controversial. In addition, owing to recent improvements in the outcomes of KT and management of cardiovascular diseases, it is necessary to analyze outcomes of recently performed KT in diabetic patients.

METHODS

We reviewed all diabetic patients who received living donor KT between January 2008 and December 2011. Each patient was age- and sex-matched with two non-diabetic patients who received living donor KT during the same period. The outcomes of living donor KT were compared between diabetic and non-diabetic patients.

RESULTS

Among 887 patients, 89 diabetic patients were compared with 178 non-diabetic patients. The incidence of acute rejection was not different between the diabetic and non-diabetic patients. Urinary tract infection and other infections as well as cardiovascular events occurred more frequently in diabetic patients. However, diabetes, cardiovascular disease, and infection were not significant risk factors of graft failure. Late rejection (acute rejection after 1 year of transplantation) was the most important risk factor for graft failure after adjusting for diabetes mellitus (DM), human leukocyte antigen mismatch, rejection and infection (hazard ratio, 56.082; 95% confidence interval, 7.169 to 438.702; p < 0.001). Mortality was not significantly different between diabetic and non-diabetic patients (0 vs. 2, p = 0.344 by log-rank test).

CONCLUSIONS

End-stage renal disease patients with DM had favorable outcomes with living donor kidney transplantation.

Midterm Outcome of Living-Related Kidney Transplantation From Aged Donors: A Single-Center Experience

BACKGROUND

Kidney transplantation (KT) is the most effective treatment of end-stage renal disease (ESRD). Using grafts from aged donors is increasing worldwide. Our aim was to better understand the safety and effectiveness of aged living donors.

METHODS

First, 482 cases with living-related kidney transplantation were analyzed retrospectively. The cases were divided into 2 groups by donor age ≥ 55 years (aged donor group, 136 cases) and <55 years (young donor group, 346 cases). Then donor and recipient characteristics were summarized. In addition, the renal function of graft was compared between young donor group and aged donor group. Finally, patient and graft survivals were examined with the use of Kaplan-Meier analysis and compared with the use of the log-rank test.

RESULTS

The mean donor estimated glomerular filtration rate (eGFR) was lower in the aged donor group compared with in the young donor group. After KT, the mean eGFR of the graft in the recipient was also lower in the aged donor group than in the young donor group. To confirm the effect of aged kidney grafts on renal function, we measured proteinuria. Compared with the young donor group, in the aged donor group incidence of proteinuria and 24-hour urinary protein were significantly higher. However, the incidence of delayed graft function was not significantly different between the 2 groups. We found that aged kidney grafts had no significant effect on long-term patient and graft survivals.

CONCLUSIONS

With the current lack of organs, aged kidney grafts are an acceptable alternative. Use of organs from aged donors safely expands the living donor pool.