Improvement in survival associated with adult-to-adult living donor liver transplantation

Abstract

Background & aims: More than 2000 adult-to-adult living donor liver transplantations (LDLT) have been performed in the United States, yet the potential benefit to liver transplant candidates of undergoing LDLT compared with waiting for deceased donor liver transplantation (DDLT) is unknown. The aim of this study was to determine whether there is a survival benefit of adult LDLT.

Methods: Adults with chronic liver disease who had a potential living donor evaluated from January 1998 to February 2003 at 9 university-based hospitals were analyzed. Starting at the time of a potential donor's evaluation, we compared mortality after LDLT to mortality among those who remained on the waiting list or received DDLT. Median follow-up was 4.4 years. Comparisons were made by hazard ratios (HR) adjusted for LDLT candidate characteristics at the time of donor evaluation.

Results: Among 807 potential living donor recipients, 389 underwent LDLT, 249 underwent DDLT, 99 died without transplantation, and 70 were awaiting transplantation at last follow-up. Receipt of LDLT was associated with an adjusted mortality HR of 0.56 (95% confidence interval [CI]: 0.42-0.74; P < .001) relative to candidates who did not undergo LDLT. As centers gained greater experience (>20 LDLT), LDLT benefit was magnified, with a mortality HR of 0.35 (95% CI: 0.23-0.53; P < .001).

Conclusions: Adult LDLT was associated with lower mortality than the alternative of waiting for DDLT. This reduction in mortality was magnified as centers gained experience with LDLT. This reduction in transplant candidate mortality must be balanced against the risks undertaken by the living donors themselves.

Figure 1

Flow diagram of the cohort of A2ALL liver transplant candidates from the time of first living donor evaluation.

Figure 2. Cumulative probability of receiving a LDLT or DDLT or dying while awaiting transplantation among 807 liver transplant candidates

The small circles mark the time of performance of the median number of LDLT (1.8 months) and DDLT (4.6 months). The probability of remaining alive while still awaiting transplantation is also shown.

Figure 3. Cumulative risk of death after initial living donor evaluation for patients receiving LDLT versus not receiving LDLT

Risk of death following LDLT diverges beginning at median time of LDLT following donor evaluation (1.8 months) (green line). Estimates are adjusted for age, MELD score, and HCC status, and apply to a patient with age=50, MELD=15, and no HCC.

Figure 4. Cumulative risk of death after initial living donor evaluation for patients not transplanted (yellow), patients receiving DDLT (red), and patients receiving LDLT during earlier (blue) and later center experience (green)

Estimates are adjusted for age, MELD score, and HCC status, and apply to a patient with age=50, MELD=15, and no HCC. Risks of death following transplant diverge beginning at the median times for each type: LDLT case ≤20 (1.7 months); LDLT case >20 (2.0 months); and DDLT (4.6 months).