Kidney Donors and Kidney Failure – Once More, With Feeling

[Clark]

http://livingdonorsarepeopletoo.com/kidney-donors-and-kidney-failure-once-more-with-feeling/

Kidney Donors and Kidney Failure – Once More, With Feeling

Recall Mjoen‘s latest research on living kidney donors who later develop end-stage renal disease? Here’s a recap: (emphasis mine)
 
Compared with controls, kidney donors had a significant 11.4 times increased risk of ESRD, 1.4 times increased risk of cardiovascular death, and 1.3 times increased risk of death from any cause, after adjusting for potential confounders.
The median time from donation was 18.7 years. ESRD was mainly caused by immunologic renal diseases.
 
In a recent issue of Kidney International, Boudville and Garg have a few remarks to make about Mjoen’s paper, specifically: (emphasis mine)
 
This paper demonstrates that living donors have poorer survival compared with matched non-donor controls, with the difference apparent only after 10 years of follow-up.
The paper also demonstrates an approximately 11-fold increase in the hazard ratio for ESRD in donors compared with matched non-donor controls.
 
And…
…an increased incidence rate of ESRD in donors compared with non-donor controls is now also corroborated in a recently presented abstract on almost 100,000 living kidney donors from the United States. In that study, the incidence rate of ESRD was eight-fold higher in donors.
 
What’s this now? Another study that says living kidney donors are at a  higher risk of kidney failure than non-donors? Written by folks in the US transplant industry??
Yes, indeed. Their conclusion (emphasis mine):
 
 Compared with matched healthy non-donors, kidney donors had an increased risk of ESRD over a median of 7.6 years;
 
Less than 10 years. Considering the average US living kidney donor is 41 years old, that’s not only significant, but potentially catastrophic. What do Boudville and Garg suggest?
 
We will likely want a higher level of predonation kidney function (estimated glomerular filtration rate >90 ml/min/ 1.73m2) for younger individuals who are expected to live 50 or more years with one kidney (recognizing we do not have ideal evidence to inform what is the optimal acceptance threshold).
 
While this suggestion is, at least, something, a one-size-fits-all measure is not the best way to protect living kidney donors. After all, just a few years ago a Joint Societies* Consensus Group document on the medical evaluation of the living kidney donor recommended cut-offs based on age. Specifically, “one standard deviation below the mean”. Not surprisingly, this was written out of the final OPTN policy, but it’s still the most clinically sound method of preserving a living kidney donor’s post-kidney function.
It’s unfortunate OPTN and the transplant industry refuse to let facts get in the way of their opinions.
 
*the “joint societies” being all transplant related
 
Boudville, N., & Garg, A. (2014). End-stage renal disease in living kidney donors Kidney International, 86 (1), 20-22 DOI: 10.1038/ki.2013.560
Muzaale, A., Massie, A., Wang, M., Montgomery, R., McBride, M., Wainright, J., & Segev, D. (2014). Risk of End-Stage Renal Disease Following Live Kidney Donation JAMA, 311 (6) DOI: 10.1001/jama.2013.285141

[Clark]

http://www.nature.com/ki/journal/v86/n1/full/ki2013560a.html

End-stage renal disease in living kidney donors
Neil Boudville1 and Amit X Garg
Kidney International (2014) 86, 20–22; doi:10.1038/ki.2013.560

The paper by Mjøen et al. raises important concerns about the long-term consequences of living donation, including a long-term increased risk of end-stage renal disease after an individual undergoes donor nephrectomy. These potential risks need to be communicated to future living kidney donors and should be an impetus for ongoing investigation.

[Clark]

http://jama.jamanetwork.com/article.aspx?articleid=1829682

Risk of End-Stage Renal Disease Following Live Kidney Donation
Abimereki D. Muzaale, MD, MPH1; Allan B. Massie, PhD1; Mei-Cheng Wang, PhD2; Robert A. Montgomery, MD, DPhil1; Maureen A. McBride, PhD3; Jennifer L. Wainright, PhD3; Dorry L. Segev, MD, PhD1,2,4
JAMA. 2014;311(6):579-586. doi:10.1001/jama.2013.285141.

Importance  Risk of end-stage renal disease (ESRD) in kidney donors has been compared with risk faced by the general population, but the general population represents an unscreened, high-risk comparator. A comparison to similarly screened healthy nondonors would more properly estimate the sequelae of kidney donation.

Objectives  To compare the risk of ESRD in kidney donors with that of a healthy cohort of nondonors who are at equally low risk of renal disease and free of contraindications to live donation and to stratify these comparisons by patient demographics.

Design, Settings, and Participants  A cohort of 96 217 kidney donors in the United States between April 1994 and November 2011 and a cohort of 20 024 participants of the Third National Health and Nutrition Examination Survey (NHANES III) were linked to Centers for Medicare & Medicaid Services data to ascertain development of ESRD, which was defined as the initiation of maintenance dialysis, placement on the waiting list, or receipt of a living or deceased donor kidney transplant, whichever was identified first. Maximum follow-up was 15.0 years; median follow-up was 7.6 years (interquartile range [IQR], 3.9-11.5 years) for kidney donors and 15.0 years (IQR, 13.7-15.0 years) for matched healthy nondonors.

Main Outcomes and Measures  Cumulative incidence and lifetime risk of ESRD.

Results  Among live donors, with median follow-up of 7.6 years (maximum, 15.0), ESRD developed in 99 individuals in a mean (SD) of 8.6 (3.6) years after donation. Among matched healthy nondonors, with median follow-up of 15.0 years (maximum, 15.0), ESRD developed in 36 nondonors in 10.7 (3.2) years, drawn from 17 ESRD events in the unmatched healthy nondonor pool of 9364. Estimated risk of ESRD at 15 years after donation was 30.8 per 10 000 (95% CI, 24.3-38.5) in kidney donors and 3.9 per 10 000 (95% CI, 0.8-8.9) in their matched healthy nondonor counterparts (P < .001). This difference was observed in both black and white individuals, with an estimated risk of 74.7 per 10 000 black donors (95% CI, 47.8-105. vs 23.9 per 10 000 black nondonors (95% CI, 1.6-62.4; P < .001) and an estimated risk of 22.7 per 10 000 white donors (95% CI, 15.6-30.1) vs 0.0 white nondonors (P < .001). Estimated lifetime risk of ESRD was 90 per 10 000 donors, 326 per 10 000 unscreened nondonors (general population), and 14 per 10 000 healthy nondonors.

Conclusions and Relevance  Compared with matched healthy nondonors, kidney donors had an increased risk of ESRD over a median of 7.6 years; however, the magnitude of the absolute risk increase was small. These findings may help inform discussions with persons considering live kidney donation.