It turns out that the answer, somewhat to my surprise, seems to be "no." (I had thought there would be some such risk.) See Mary D. Ellison et al., Living Kidney Donors in Need of Kidney Transplants: A Report from Organ Procur. & Transp. Net., 74 Transplantation 1349 (2002) (noting that the best current estimates of the risk of kidney donors' eventually developing end-stage renal disease "approximate[] the . . . adjusted incident rate for end-stage renal disease in the general U.S. population"); Margaret J. Bia et al., Evaluation of Living Renal Donors, 60 Transplantation 322, 326 (1995) (same).

I stress "seems to," because even though we do have decades of data, the studies have some understandable limitations. But the studies do suggest that there is no such elevated risk, and in any event it appears that even if there is some elevated risk that the studies don't catch, it's unlikely to be very high.

I'll update my article draft accordingly, but since the issue had come up in my posts and the comments to those posts, I'd note it. Recall that transplant operations do involve a roughly 0.03% chance of relatively prompt donor death, and a 2% or less chance of serious complications.