Chronic kidney disease is associated with significant morbidity and mortality in the general population, but little is known about the incidence and risk factors associated with developing low estimated glomerular filtration rate (eGFR) and moderate-severe albuminuria in living kidney donors following nephrectomy.
Two eGFR measurements <45 mL/min/1.73 m 2 or 2 measurements of moderate or severe albuminuria from 1-year postdonation onwards that were at least 90 days apart.
Associations between potential risk factors and the primary outcome were assessed using Cox proportional hazard regression analyses.
Over a median follow-up period of 8.6 years (IQR, 4.7-12.6 years), 47 of 590 donors (8.0%) developed sustained low eGFR or moderate-severe albuminuria with an incidence rate of 9.2 per 1,000 person-years (95% confidence interval, 6.6-11.8). The median time for development of this outcome beyond the first year after nephrectomy was 2.9 years (IQR, 1.4-8.0 years). Within the first 4 years of follow-up, a 5 mL/min/1.73 m 2 lower predonation eGFR increased the hazard of developing postdonation low eGFR or moderate-severe albuminuria by 26% (adjusted HR, 1.26; 95% CI, 1.10-1.44). Furthermore, donors were at higher risk of developing low eGFR or albuminuria if they had evidence of predonation hypertension (adjusted HR, 2.52; 95% CI, 1.28-4.96) or postdonation diabetes (adjusted HR, 4.72; 95% CI, 1.54-14.50).
The purpose of this study was to understand the risk of developing kidney disease in living kidney donors after donation. We followed 590 donors in Alberta, Canada for almost 9 years. Approximately 8% of donors developed reduced kidney function (low estimated glomerular filtration rate) or increased protein in the urine (albuminuria). Donors with lower kidney function before donation, hypertension before donation, or diabetes after donation had a higher likelihood of experiencing these kidney outcomes. This research provides important insights to patients and health care providers to better support the long-term kidney health of living kidney donors.