Reply: Quality of life in actual living liver donors versus potential living liver donors

Abstract

TO THE EDITORS:We thank Butt et al. 1 for their interest in our article on quality of life (QOL) in actual and potential living liver donors.2 In reply, we would like to address their methodological concerns.The first concern is related to the composition of the control group and the retention rate. In our view, the exclusion of 13 potential donors due to additional exclusion criteria does not lower the retention rate because those patients did not constitute a valid control group from the beginning. They were rejected as donors either for psychosocial reasons or because their recipients did not undergo transplantation. Therefore, they were not comparable to actual donors, who were, of course, deemed psychologically eligible and whose recipients underwent transplantation. We consider the exclusion criteria to be necessary in order to ensure comparability with the group of actual donors. Individuals who do not meet these criteria are not suitable as controls.Nevertheless, we would like to address the problem of the retention rate in more detail. As stated in our article, 2 the overall response rate of 64% for the preoperative time point is lowered further because only 60% of these responders also returned their questionnaires at the postoperative time point. However, for the aforementioned reasons, it would have been more consistent if we had applied the exclusion criteria before we calculated the response rate. We would like to supplement this information. If the exclusion criteria constituting eligibility in the control group are applied beforehand, 33 of the 88 patients who did not donate have to be excluded. This means that of 55 eligible control patients at the time of donor evaluation (t 0 ), 33 also participated 3 months after transplantation, and this constitutes a response rate of 60% for the potential donors. This results in a dropout rate of 30% for the actual donors and a dropout rate of 40% for the potential donors.We were able to compare the dropouts and the patients who completed their questionnaires at both time points with respect to sociodemographic and clinical variables as well as QOL at t 0 . For this analysis, the exclusion criteria were applied beforehand so that only those potential donors who constituted a suitable control group were included. For the dropout analysis, we did not differentiate between actual and potential donors because this group difference is not relevant preoperatively. The analysis revealed no significant differences with respect to QOL, anxiety, depression, or abdominal symptoms at t 0 . However, significant differences between responders (who returned questionnaires at both time points) and dropouts (who returned questionnaires only at t 0 ) were found with respect to the transplant center (42% dropout rate in Essen and 21% dropout rate in Hamburg; P ¼ 0.03), donor group (46% dropout rate among patients donating for adult recipients and 13% dropout rate among patients donating for pediatric recipients; P < 0.001), donor-recipient relationship (17% dropout rate among...