To investigate the effect of diabetes mellitus on the survival rate of liver transplant recipients with different grades of acute-on-chronic liver failure (ACLF) after liver transplantation.

A retrospective study was carried out to investigate 1, 144 recipients with ACLF who underwent liver transplantation from January 1, 2017 to December 31, 2017 in the Scientific Registry of Transplant Recipients of American. According to whether they had diabetes before transplantation, the recipients were divided into two groups: non-diabetic group (n=927) and diabetic group (n=217). The survival rate was calculated by the Kaplan-Meier method and the survival curve was drawn, and then the log-rank test was used to compare the differences between two groups. The Cox proportional-hazards model was used to analyze the independent prognostic factors. A two-tailed P value <0.05 was considered statistically significant.

There were statistically significant differences in recipients′ age, body mass index (BMI), underlying liver disease, model for end-stage liver disease score, ACLF grade and postoperative hospital stay between diabetic and non-diabetic group (U/χ²=-6.290, -3.592, 76.451, -2.959, 8.150 and-2.542, all P <0.05). In terms of the donor characteristics, there was significant statistical difference in ABO blood type between the two groups (χ²=8.463, P<0.05). The proportion of recipients died from multiple organ failure after liver transplantation in the non-diabetic group (1.54%) was significantly lower than that in the diabetic group (5.16%) (χ²=8.863, P<0.05). There were no significant differences in terms of graft failure, cardio-cerebrovascular disease, hemorrhage, infection, malignant tumor and other diseases between the two groups (all P>0.05). The 1-, 2- and 3-year survival rates of ACLF1 recipients in the non-diabetic group were 93.1%, 90.5% and 88.7% by September 1, 2021, while those in the diabetic group were 93.8%, 92.2% and 92.2%, which had no statistically significance (χ²=1.021, P>0.05). The corresponding survival rates of ACLF2 recipients in non-diabetic group were 93.6%, 89.8% and 88.4% respectively, while those in diabetic group were 96.8%, 95.7% and 90.3%, which had no statistically significance (χ²=0.850, P>0.05). The corresponding survival rates of ACLF3 recipients in non-diabetic group were 91.5%, 89.2% and 87.5%, significantly better than those in diabetic group, which were 80.0%, 71.7% and 71.7% respectively (χ²=11.444, P<0.05). Multivariate analysis showed that recipient diabetes, ethnicity (African) and BMI were independent predictors of survival after liver transplantation in ACLF3 recipients (HR=2.31, 2.13 and 1.04, all P<0.05).

Diabetes can significantly reduce the survival rates of ACLF3 recipients after liver transplantation, but it has no significant effect on ACLF1 and ACLF2 recipients. It is important to assess the diabetes status in ACLF3 recipients in the recipient selection process, in order to achieve better post-transplant survival.