Self-reported incident hypertension and long-term kidney function in living kidney donors compared with healthy nondonors

Background and objectives The risk of hypertension attributable to living kidney donation remains unknown as does the effect of developing postdonation hypertension on subsequent eGFR. We sought to understand the association between living kidney donation, hypertension, and long-term eGFR by comparing donors with a cohort of healthy nondonors. Design, setting, participants, & measurements We compared 1295 living kidney donors with median 6 years of follow-up with a weighted cohort of 8233 healthy nondonors. We quantified the risk of self-reported hypertension using a parametric survival model. We examined the association of hypertensionwith yearly change in eGFR using multilevel linear regression and clustering by participant, with an interaction term for race. Results Kidney donation was independently associated with a 19% higher risk of hypertension (adjusted hazard ratio, 1.19; 95% confidence interval, 1.01 to 1.41; P=0.04); this association did not vary by race (interaction P=0.60). For white and black nondonors, there was a mean decline in eGFR (20.4 and 20.3 ml/min per year, respectively) that steepened after incident hypertension (20.8 and 20.9 ml/min per year, respectively; both P,0.001). For white and black kidney donors, there was a mean increase in eGFR after donation (+0.4 and +0.6 ml/min per year, respectively) that plateaued after incident hypertension (0 and 20.2 ml/min per year, respectively; P=0.07 and P=0.01, respectively, after hypertension). Conclusions Kidney donors are at higher risk of hypertension than similar healthy nondonors, regardless of race. Donors who developed hypertension had a plateau in the usual postdonation increase of eGFR.