Long-term outcomes of kidney donors with fibromuscular dysplasia

Abstract

Fibromuscular dysplasia (FMD) is a non-atherosclerotic systemic arterial disease that is not infrequently discovered during kidney donor evaluation. Current guidelines do not provide recommendations regarding the use of kidneys from donors with FMD and there is a paucity of data on the outcomes of these donors. The Renal and Lung Living Donor Evaluation (RELIVE) Study addressed long-term outcomes of 8922 kidney donors who donated 1963 - 2007. We compared the development of hypertension, cardiovascular disease, proteinuria and reduced eGFR in 113 kidney donors with FMD discovered during donor evaluation to 452 propensity score matched donors without FMD. Outcomes modeling with logistic and Cox regression analysis and Kaplan Meier statistics were performed. Donors with FMD were older (51 vs. 39 years), were more likely to be women (80% vs. 56%) and had a higher systolic blood pressure at donation (124.7 vs. 121.3 mmHg), p < 0.05 for all. After a mean follow-up of 15.5 ± 8.9 years, a similar proportion of donors with and without FMD were alive, developed hypertension (22.2% vs 19.8%), proteinuria (20.6% vs 13.7%) and CVD (13.3% vs 13.5%). No donor with FMD developed an eGFR <30 ml/min/1.73 m2 or ESKD. The multivariable risk of mortality, cardiovascular disease and renal outcomes in donors with FMD were not elevated. Kidney donors with FMD appear to do well, do not appear to incur increased risks of hypertension, proteinuria, CVD or reduced eGFR and perhaps carefully selected candidates with FMD can safely donate as long as involvement of other vascular beds is ruled out.