Long-term consequences of kidney donation

Abstract

Background: The long-term renal consequences of kidney donation by a living donor are attracting increased appropriate interest. The overall evidence suggests that living kidney donors have survival similar to that of nondonors and that their risk of end-stage renal disease (ESRD) is not increased. Previous studies have included relatively small numbers of donors and a brief follow-up period.

Methods: We ascertained the vital status and lifetime risk of ESRD in 3698 kidney donors who donated kidneys during the period from 1963 through 2007; from 2003 through 2007, we also measured the glomerular filtration rate (GFR) and urinary albumin excretion and assessed the prevalence of hypertension, general health status, and quality of life in 255 donors.

Results: The survival of kidney donors was similar to that of controls who were matched for age, sex, and race or ethnic group. ESRD developed in 11 donors, a rate of 180 cases per million persons per year, as compared with a rate of 268 per million per year in the general population. At a mean (+/-SD) of 12.2+/-9.2 years after donation, 85.5% of the subgroup of 255 donors had a GFR of 60 ml per minute per 1.73 m(2) of body-surface area or higher, 32.1% had hypertension, and 12.7% had albuminuria. Older age and higher body-mass index, but not a longer time since donation, were associated with both a GFR that was lower than 60 ml per minute per 1.73 m(2) and hypertension. A longer time since donation, however, was independently associated with albuminuria. Most donors had quality-of-life scores that were better than population norms, and the prevalence of coexisting conditions was similar to that among controls from the National Health and Nutrition Examination Survey (NHANES) who were matched for age, sex, race or ethnic group, and body-mass index.

Conclusions: Survival and the risk of ESRD in carefully screened kidney donors appear to be similar to those in the general population. Most donors who were studied had a preserved GFR, normal albumin excretion, and an excellent quality of life.

Figure 1. Survival of Kidney Donors and Controls from the General Population

I bars at 5-year intervals indicate 95% confidence intervals for the probability of survival among kidney donors.

Figure 2. Glomerular Filtration Rate (GFR) and Urinary Albumin Excretion According to Time since Donation

Panel A shows the GFR, and Panel B shows log-transformed values for the ratio of urinary albumin to creatinine. In each panel, the solid line indicates the regression line, and the dotted line, the 95% confidence interval.

Figure 3. Quality-of-Life Scores for Kidney Donors

The physical-health and mental-health summary scores, adjusted for age and sex, as compared with population norms, are shown in Panels A and B, respectively. In the case of the physical-health summary score, 40.4% of the scores were below the mean, and 59.6% were above the mean. In the case of the mental-health summary score, 38.0% of the scores were below the mean, and 62.0% were above the mean. The blue lines in Panels A and B represent the population norms. The relationship of the physical-health and mental-health summary scores, adjusted for age and sex, to time since donation is shown in Panels C and D, respectively. The lines in Panels C and D are the regression lines.