Study of Long-term Outcomes in Living Liver Donors

概要

研究I
We retrospectively reviewed 220 living liver donors, with a focus on the development of postoperative fatty liver. Data regarding demographics, comorbidities, imaging tests, operations, and biopsies were obtained from medical records. We used unenhanced CT and USG to diagnose fatty liver. Donor candidates with fatty liver underwent weight loss intervention until imaging tests no longer demonstrated any features of fatty liver. Among 220 donors, 61 were diagnosed with preoperative fatty liver. The mean BMI of these 61 donors significantly decreased from 24.9 at the first visit to 23.6 kg/m2 immediately before surgery (p=0.0386). A multivariate analysis revealed the following significant risk factors for postoperative fatty liver: male sex (p=0.0033), BMi immediately before surgery (p=0.0028), and a history of treatment for preoperative fatty liver (p=0.0231). Postoperative fatty liver was often refractory to weight loss intervention. No improvement was observed in 14 of the 32 donors who had been diagnosed with fatty liver postoperatively, and 1 of the 14 donors even developed NASH. In conclusion, special attention should be paid to prevent fatty liver after surgery in male donors who show a high BMI immediately before surgery and with a history of treatment for preoperative fatty liver, and lifelong follow-up is recommended.

研究Ⅱ
In recent years, the increasing number of obese individuals in Japan has made transplant teams sometimes forced to select candidates with a high body mass index (BMI) as marginal donors in living donor liver transplantation. However, data are lacking regarding the impact of a high BMI on the outcome for liver donors, particularly over the long term. Here, we aimed to clarify the impact of a high BMI on postoperative short- and long-term outcomes in liver donors. We selected 80 cases that had complete 5-year data available from hepatectomies performed in 2005-2015 in Osaka University Hospital. We divided donors into overweight (BMI>25 kg/m2, n=16) and normal-weight (BMI<25, n=64) groups. Preoperatively, the overweight group had significantly higher preoperative levels of serum alanine aminotransferase and y- glutamyl transpeptidase and a larger liver volume than the normal-weight group. Although the overweight group had significantly greater intraoperative blood loss (660±455 vs. 312±268 mL, p=0.0018) and longer operation times (463±88 vs. 386±79 min, p=0.0013), the groups showed similar frequencies of postoperative complications. At 1 year post-hepatectomy, liver regeneration and spleen enlargement ratios did not significantly differ between the two groups. Remarkably, the overweight group showed significantly higher serum y-glutamyl transpeptidase levels over the long-term. Overweight status alone was not a risk factor for either short- or long-term postoperative outcomes after a donor hepatectomy. However, donors with elevated y-glutamyl transpeptidase levels, which was frequent among overweight donors, may require special attention.