Outcomes of Kidney Donors With Impaired Fasting Glucose

Pros and cons of live kidney donation in prediabetics: A critical review and way forward

There is shortage of organs, including kidneys, worldwide. Along with deceased kidney transplantation, there is a significant rise in live kidney donation. The prevalence of prediabetes (PD), including impaired fasting glucose and impaired glucose tolerance, is on the rise across the globe. Transplant teams frequently come across prediabetic kidney donors for evaluation. Prediabetics are at risk of diabetes, chronic kidney disease, cardiovascular events, stroke, neuropathy, retinopathy, dementia, depression and nonalcoholic liver disease along with increased risk of all-cause mortality. Unfortunately, most of the studies done in prediabetic kidney donors are retrospective in nature and have a short follow up period. There is lack of prospective long-term studies to know about the real risk of complications after donation. Furthermore, there are variations in recommendations from various guidelines across the globe for donations in prediabetics, leading to more confusion among clinicians. This increases the responsibility of transplant teams to take appropriate decisions in the best interest of both donors and recipients. This review focuses on pathophysiological changes of PD in kidneys, potential complications of PD, other risk factors for development of type 2 diabetes, a review of guidelines for kidney donation, the potential role of diabetes risk score and calculator in kidney donors and the way forward for the evaluation and selection of prediabetic kidney donors.

Diabetes-free survival among living kidney donors and non-donors with obesity: A longitudinal cohort study

BACKGROUND

Approval of living kidney donors (LKD) with end-stage kidney disease (ESKD) risk factors, such as obesity, has increased. While lifetime ESKD development data are lacking, the study of intermediate outcomes such as diabetes is critical for LKD safety. Donation-attributable diabetes risk among persons with obesity remains unknown. The purpose of this study was to evaluate 10-year diabetes-free survival among LKDs and non-donors with obesity.

METHODS

This longitudinal cohort study identified adult, LKDs (1976-2020) from 42 US transplant centers and non-donors from the Coronary Artery Risk Development in Young Adults (1985-1986) and the Atherosclerosis Risk in Communities (1987-1989) studies with body mass index ≥30 kg/m2. LKDs were matched to non-donors on baseline characteristics (age, sex, race, body mass index, systolic and diastolic blood pressure) plus diabetes-specific risk factors (family history of diabetes, impaired fasting glucose, smoking history). Accelerated failure time models were utilized to evaluate 10-year diabetes-free survival.

FINDINGS

Among 3464 participants, 1119 (32%) were LKDs and 2345 (68%) were non-donors. After matching on baseline characteristics plus diabetes-specific risk factors, 4% (7/165) LKDs and 9% (15/165) non-donors developed diabetes (median follow-up time 8.5 (IQR: 5.6-10.0) and 9.1 (IQR: 5.9-10.0) years, respectively). While not significant, LKDs were estimated to live diabetes-free 2 times longer than non-donors (estimate 1.91; 95% CI: 0.79-4.64, p = 0.15).

CONCLUSIONS

LKDs with obesity trended toward living longer diabetes-free than non-donors with obesity, suggesting within the decade following donation there was no increased diabetes risk among LKDs. Further work is needed to evaluate donation-attributable diabetes risk long-term.

Intermediate Renal Outcomes, Kidney Failure, and Mortality in Obese Kidney Donors

BACKGROUND

Obesity is associated with the two archetypal kidney disease risk factors: hypertension and diabetes. Concerns that the effects of diabetes and hypertension in obese kidney donors might be magnified in their remaining kidney have led to the exclusion of many obese candidates from kidney donation.

METHODS

We compared mortality, diabetes, hypertension, proteinuria, reduced eGFR and its trajectory, and the development of kidney failure in 8583 kidney donors, according to body mass index (BMI). The study included 6822 individuals with a BMI of <30 kg/m2, 1338 with a BMI of 30-34.9 kg/m2, and 423 with a BMI of ≥35 kg/m2. We used Cox regression models, adjusting for baseline covariates only, and models adjusting for postdonation diabetes, hypertension, and kidney failure as time-varying covariates.

RESULTS

Obese donors were more likely than nonobese donors to develop diabetes, hypertension, and proteinuria. The increase in eGFR in obese versus nonobese donors was significantly higher in the first 10 years (3.5 ml/min per 1.73m2 per year versus 2.4 ml/min per 1.73m2 per year; P<0.001), but comparable thereafter. At a mean±SD follow-up of 19.3±10.3 years after donation, 31 (0.5%) nonobese and 12 (0.7%) obese donors developed ESKD. Of the 12 patients with ESKD in obese donors, 10 occurred in 1445 White donors who were related to the recipient (0.9%). Risk of death in obese donors was not significantly increased compared with nonobese donors.

CONCLUSIONS

Obesity in kidney donors, as in nondonors, is associated with increased risk of developing diabetes and hypertension. The absolute risk of ESKD is small and the risk of death is comparable to that of nonobese donors.