We know that if a donor gets a kidney disease that their progression to dialysis would be faster than if they had 2 kidneys. This study is 15 years later, maybe too early for matched controls to develope ESRD? Maybe they had some level of CKD but not ESRD.? Would need more information on how this was conducted.
Potential donors need to understand that their risk of ESRD is the same as "people just like them" risk for blacks is higher than whites, if your whole family has HTN your risk is higher , if your family is diabetic your risk is higher etc....again the only difference is that you would progress to ESRD faster than people with two kidneys.