Long-term Mortality Risks Among Living Kidney Donors in Korea.

Living kidney donors may have a higher risk for death and kidney failure. This study aimed to investigate the long-term mortality experience of living kidney donors compared with members of the general public in Korea who underwent voluntary health examinations. Cohort study. We first calculated standardized mortality ratios for 1,292 Korean living kidney donors who underwent donor nephrectomy between 1982 and 2016 and 72,286 individuals who underwent voluntary health examinations between 1995 and 2016. Next we compared survival between the 1,292 living kidney donors and a subgroup of the health examination population (n=33,805) who had no evident contraindications to living kidney donation at the time of their examinations. Last, a matched comparator group was created from the health examination population without apparent contraindication to donation by matching 4,387 of them to donors (n=1,237) on age, sex, body mass index, estimated glomerular filtration rate, urine dipstick albumin excretion, previously diagnosed hypertension and diabetes, and era. Donor nephrectomy. All-cause mortality and other clinical outcomes after kidney donation. First, standardized mortality ratios were calculated separately for living kidney donors and the health examination population standardized to the general population. Second, we used Cox regression analysis to compare mortality between living kidney donors versus the subgroup of the health examination population without evident donation contraindications. Third, we used Cox regression analysis to compare mortality between living kidney donors and matched comparators from the health examination population without apparent contraindication to donation. The living kidney donors and health examination population had excellent survival rates compared with the general population. 52 (4.0%) of 1,292 kidney donors died during a mean follow-up of 12.3±8.1 years and 1,072 (3.2%) of 33,805 in the health examiner subgroup without donation contraindications died during a mean follow-up of 11.4±6.1 years. Donor nephrectomy did not elevate the hazard for mortality after multivariable adjustment in kidney donors and the 33,805 comparators (adjusted HR, 1.01; 95% CI, 0.71-1.44; P=0.9). Moreover, living donors showed a similar mortality rate compared with the group of matched healthy comparators. Donors from a single transplantation center. Residual confounding owing to the observational study design. Kidney donors experienced long-term rates of death comparable to nondonor comparators with similar health status.

Kim Y ，Yu MY ，Yoo KD ，Jeong CW ，Kim HH ，Min SI ，Ha J ，Choi Y ，Ko AR ，Yun JM ，Park SM ，Yang SH ，Kim DK ，Oh KH ，Joo KW ，Ahn C ，Kim YS ，Lee H ... -  《-》

Implications of excess weight on kidney donation: Long-term consequences of donor nephrectomy in obese donors.

An elevated body mass index (>30 kg/m2) has been a relative contraindication for living kidney donation; however, such donors have become more common. Given the association between obesity and development of diabetes, hypertension, and end-stage renal disease, there is concern about the long-term health of obese donors. Donor and recipient demographics, intraoperative parameters, complications, and short- and long-term outcomes were compared between contemporaneous donors-obese donors (body mass index ≥30 kg/m2) versus nonobese donors (body mass index <30 kg/m2). Between the years 1975 and 2014, we performed 3,752 donor nephrectomies; 656 (17.5%) were obese donors. On univariate analysis, obese donors were more likely to be older (P < .01) and African American (P < .01) and were less likely to be a smoker at the time of donation (P = .01). Estimated glomerular filtration rate at donation was higher in obese donors (115 ± 36 mL/min/1.73m2) versus nonobese donors (97 ± 22 mL/min/1.73m2; P < .001). There was no difference between groups in intraoperative and postoperative complications; but intraoperative time was longer for obese donors (adjusted P < .001). Adjusted postoperative length of stay (LOS) was longer (adjusted P = .01), but after adjustment for donation year, incision type, age, sex, and race, there were no differences in short-term (<30 days) and long-term (>30 days) readmissions. Estimated glomerular filtration rate and rates of end-stage renal disease were not significantly different between donor groups >20 years after donation (P = .71). However, long-term development of diabetes mellitus (adjusted hazard ratio (HR) 3.14; P < .001) and hypertension (adjusted hazard ratio (HR) 1.75; P < .001) was greater among obese donors and both occurred earlier (diabetes mellitus: 12 vs 18 years postnephrectomy; hypertension: 11 vs 15 years). Obese donors develop diabetes mellitus and hypertension more frequently and earlier than nonobese donors after donation, raising concerns about increased rates of end-stage renal disease.

Serrano OK ，Sengupta B ，Bangdiwala A ，Vock DM ，Dunn TB ，Finger EB ，Pruett TL ，Matas AJ ，Kandaswamy R ... -  《-》

Obesity and long-term mortality risk among living kidney donors.

Body mass index of living kidney donors has increased substantially. Determining candidacy for live kidney donation among obese individuals is challenging because many donation-related risks among this subgroup remain unquantified, including even basic postdonation mortality. We used data from the Scientific Registry of Transplant Recipients linked to data from the Centers for Medicare and Medicaid Services to study long-term mortality risk associated with being obese at the time of kidney donation among 119,769 live kidney donors (1987-2013). Donors were followed for a maximum of 20 years (interquartile range 6.0-16.0). Cox proportional hazards estimated the risk of postdonation mortality by obesity status at donation. Multiple imputation accounted for missing obesity data. Obese (body mass index ≥ 30) living kidney donors were more likely male, African American, and had higher blood pressure. The estimated risk of mortality 20 years after donation was 304.3/10,000 for obese and 208.9/10,000 for nonobese living kidney donors. Adjusting for age, sex, race/ethnicity, blood pressure, baseline estimated glomerular filtration rate, relationship to recipient, smoking, and year of donation, obese living kidney donors had a 30% increased risk of long-term mortality compared with their nonobese counterparts (adjusted hazard ratio: 1.32, 95% CI: 1.09-1.60, P = .006). The impact of obesity on mortality risk did not differ significantly by sex, race or ethnicity, biologic relationship, baseline estimated glomerular filtration rate, or among donors who did and did not develop postdonation kidney failure. These findings may help to inform selection criteria and discussions with obese persons considering living kidney donation.

Locke JE ，Reed RD ，Massie AB ，MacLennan PA ，Sawinski D ，Kumar V ，Snyder JJ ，Carter AJ ，Shelton BA ，Mustian MN ，Lewis CE ，Segev DL ... -  《-》

Increasing Use of the Expanded Criteria for Living Kidney Donation and Good Outcomes of Living Kidney Donors in Korea.

Donor shortage for kidney transplantation may increase the number of expanded-criteria living donors (ECLDs). We investigated recent trends for ECLD use and the long-term outcomes of living kidney donors. We retrospectively analyzed medical records of 1,144 living kidney donors who donated at the Seoul National University Hospital from 1993 to 2015. The expanded criteria for living donation allow the following: age ≥60 years, body mass index >30 kg/m2, history of hypertension, estimated glomerular filtration rate <80 mL/min, proteinuria or microscopic hematuria, and fasting glucose >100 mg/dL. The mean age of donors was 40.7 ± 10.8 years, and there were 600 women (52.4%). A total of 466 donors (40.7%) met the ECLD criteria, and the proportion of ECLDs increased over time. Only 5 donors died after donation over a median follow-up of 7 years. No donor developed end-stage renal disease (ESRD). A urine protein-creatinine ratio ≥0.3 g/gCr was found in 14 patients and was more common in the ECLDs than in the standard-criteria living donors. The follow-up loss rate of donors was 59.3% at 5 years. Both mortality and ESRD were very rare in carefully selected living kidney donors. However, living donors should be followed more carefully, because the follow-up loss rate was very high and ECLDs are increasingly used.

Lim HJ ，Jambaldorj E ，Lee Y ，Kang SS ，Koo TY ，Ahn C ，Yang J ... -  《-》

The Minnesota attributable risk of kidney donation (MARKD) study: a retrospective cohort study of long-term (> 50 year) outcomes after kidney donation compared to well-matched healthy controls.

There is uncertainty about the long-term risks of living kidney donation. Well-designed studies with controls well-matched on risk factors for kidney disease are needed to understand the attributable risks of kidney donation. The goal of the Minnesota Attributable Risk of Kidney Donation (MARKD) study is to compare the long-term (> 50 years) outcomes of living donors (LDs) to contemporary and geographically similar controls that are well-matched on health status. University of Minnesota (n = 4022; 1st transplant: 1963) and Mayo Clinic LDs (n = 3035; 1st transplant: 1963) will be matched to Rochester Epidemiology Project (REP) controls (approximately 4 controls to 1 donor) on the basis of age, sex, and race/ethnicity. The REP controls are a well-defined population, with detailed medical record data linked between all providers in Olmsted and surrounding counties, that come from the same geographic region and era (early 1960s to present) as the donors. Controls will be carefully selected to have health status acceptable for donation on the index date (date their matched donor donated). Further refinement of the control group will include confirmed kidney health (e.g., normal serum creatinine and/or no proteinuria) and matching (on index date) of body mass index, smoking history, family history of chronic kidney disease, and blood pressure. Outcomes will be ascertained from national registries (National Death Index and United States Renal Data System) and a new survey administered to both donors and controls; the data will be supplemented by prior surveys and medical record review of donors and REP controls. The outcomes to be compared are all-cause mortality, end-stage kidney disease, cardiovascular disease and mortality, estimated glomerular filtration rate (eGFR) trajectory and chronic kidney disease, pregnancy risks, and development of diseases that frequently lead to chronic kidney disease (e.g. hypertension, diabetes, and obesity). We will additionally evaluate whether the risk of donation differs based on baseline characteristics. Our study will provide a comprehensive assessment of long-term living donor risk to inform candidate living donors, and to inform the follow-up and care of current living donors.

Vock DM ，Helgeson ES ，Mullan AF ，Issa NS ，Sanka S ，Saiki AC ，Mathson K ，Chamberlain AM ，Rule AD ，Matas AJ ... -  《BMC Nephrology》