Outcomes and Risk Factors for Liver Transplantation Using Graft-to-Recipient Weight Ratio Less Than 0.8 Graft From Living Donors
Deok Gie Kim, Shin Hwang, Jong Man Kim, YoungRok Choi, Young Kyoung You, Dong Lak Choi, Je Ho Ryu, Bong‐Wan Kim, Dong‐Sik Kim, Jai Young Cho, Man Ki Ju, Tae‐Seok Kim, Yang Won Nah, Jae Geun Lee, Myoung Soo Kim, Dong Jin Joo, the Korean Organ Transplantation Registry Study Group
Abstract
OBJECTIVE: To compare graft survival after living donor liver transplantation (LDLT) in patients receiving graft-to-recipient weight ratio (GRWR) <0.8 versus GRWR≥0.8 grafts and identify risk factors for graft loss using GRWR<0.8 grafts. BACKGROUND: Favorable outcomes after LDLT using GRWR<0.8 grafts were recently reported; however, these results have not been validated using multicenter data. METHODS: This multicentric cohort study included 3450 LDLT patients. Graft survival was compared between 1:3 propensity score-matched groups and evaluated using various Cox models in the entire population. Risk factors for graft loss with GRWR<0.8 versus GRWR≥0.8 grafts were explored within various subgroups using interaction analyses, and outcomes were stratified according to the number of risk factors. RESULTS: In total, 368 patients (10.7%) received GRWR<0.8 grafts (GRWR<0.8 group), whereas 3082 (89.3%) received GRWR≥0.8 grafts (GRWR≥0.8 group). The 5-year graft survival rate was significantly lower with GRWR<0.8 grafts than with GRWR≥0.8 grafts (85.2% vs 90.1%, P =0.013). Adjusted hazard ratio for graft loss using GRWR<0.8 grafts in the entire population was 1.66 (95% CI: 1.17-2.35, P =0.004). Risk factors exhibiting significant interactions with GRWR<0.8 for graft survival were age ≥60 years, Model for End-stage Liver Disease score ≥15, and male donor. When ≥2 risk factors were present, GRWR<0.8 grafts showed a higher risk of graft loss compared with GRWR≥0.8 graft in LDLT (hazard ratio 2.98, 95% CI: 1.79-4.88, P <0.001). CONCLUSIONS: GRWR<0.8 graft showed inferior graft survival than controls (85.2% vs 90.1%), especially when ≥2 risk factors for graft loss (among age 60 years or above, Model for End-stage Liver Disease score ≥15, or male donor) were present.