Donating kidney does not appear to significantly increase long-term risk of death

An analysis of outcomes for live kidney donors in the US over a 15 year period finds they have similar long-term survival rates compared to healthy individuals who were not kidney donors, according to a study in the 10 March issue of JAMA.

Many patients with end-stage renal (kidney) disease are turning to live donor kidney transplantation to improve survival and quality of life because of the shortage of organs available from the deceased donor pool. "Although many healthy adults are eager and willing to accept the risk of donor nephrectomy [surgical removal of a kidney] to help their loved ones, the responsibility lies within the medical community to quantify these risks as best as possible and to make this information available to those considering donation," the authors write. More than 6,000 healthy US individuals every year undergo nephrectomy for the purposes of live donation; however, safety remains in question because of the limited generalisability of previous studies, according to background information in the article.

Dorry L. Segev, MD, PhD, of the Johns Hopkins University School of Medicine, Baltimore, and colleagues examined the outcomes of live kidney donors (80,347) in the United States between 1 April 1994 and 31 March 2009 who were drawn from a mandated national registry. Median (midpoint) follow-up was 6.3 years. A matched group was drawn from 9,364 participants of the third National Health and Nutrition Examination Survey (NHANES III).

During the study period, there were 25 deaths within 90 days of live kidney donation, with the risk of death being 3.1 per 10,000 donors, compared to a rate of death for the NHANES III matched group of 0.4 per 10,000 persons. By 1 year following nephrectomy, risk of death in the matched group was similar to the live donor group, likely representing deaths attributable to comorbidity (co-existing illnesses) rather than death because of the surgery. The researchers found that long-term mortality was similar or lower for live kidney donors than for the matched NHANES III group throughout the 12-year period of follow-up (5-year follow-up, 0.4 percent vs. 0.9 percent; 12-year follow-up, 1.5 percent vs. 2.9 percent, respectively).

"Surgical mortality did not change during the 15-year period, despite differences in surgical practice and donor selection. Men had a statistically significantly higher surgical mortality than women did, as did black individuals vs. white and Hispanic individuals," the authors write. Donors with hypertension also had a statistically significantly higher surgical mortality than did donors without hypertension.

"Regardless of what physiologic changes might occur in a healthy adult after kidney donation, our findings of similar long-term survival between donors and healthy comparison patients suggest that these physiologic changes do not result in premature death. Although additional studies are clearly needed to better understand the physiologic changes after kidney donation, the current practice of live kidney donation should continue to be considered a reasonable and safe modality for addressing the profound shortage in deceased donor organs," the authors conclude.

(Source: JAMA/Archives: JAMA: March 2010)