Although kidney transplantation from the donation of a living donor is a safe treatment for end-stage renal disease, inferences about safety of living kidney donors might be biased by an informative censoring caused by the noninclusion of a substantial percentage of donors lost to follow-up. With the aim of assessing the presence of a potential informative censoring in living kidney donation outcomes of Catalan donors for a period of 12 years, 573 donors followed and lost to follow-up were compared. Losses of follow-up over time were also assessed by univariate and multivariate survival analysis, along with Cox regression. Younger and older ages, and the death of their recipient differentiated those donors who were lost to follow-up over time. The risk of dropping out from follow-up was more than twofold for the youngest and oldest donors, and almost threefold for those donors whose recipient died. Results of studies on postdonation outcomes of Catalan living kidney donors might have overlooked older and younger cases, and, remarkably, a percentage of donors whose recipient died. If these donors showed a higher incidence of psychological problems, conclusions about living donors' safety might be compromised thus emphasizing the necessity of sustained surveillance of donors and prompt identification of these cases.