KINDERGARTEN-AGE NEUROCOGNITIVE AND FUNCTIONAL OUTCOMES AFTER LIVER TRANSPLANTATION DONE AT AGE <6 YEARS

BACKGROUND Mortality after liver transplant has improved, making long-term outcomes increasingly important. OBJECTIVES To describe neurocognitive and functional outcomes after liver transplant done in young children, and determine potentially modifiable risk factors for adverse outcomes. DESIGN/METHODS Between 1999–2014, all <6 years old liver transplant recipients at our center were enrolled in this ethics board approved, longitudinal inception-cohort. Demographic, pre-transplant, transplant, and post-transplant data were prospectively collected. Following informed consent, outcomes were determined by experienced paediatric psychologists using Wechsler Preschool and Primary Scale of Intelligence III, Beery-Buktenica Developmental Test of Visual-Motor Integration-V (VMI), and Adaptive Behavior Assessment System-II. Associations with outcomes (Full-Scale intelligence quotient [FSIQ], Performance IQ [PIQ], Verbal IQ [VIQ], VMI and General Adaptive Composite [GAC]) were determined using multiple linear regression. Population norms for each score are mean 100 (SD15). RESULTS 78 liver transplants were performed; 69 patients survived, and all completed follow-up. Outcomes for the 60 patients without metabolic disease are reported. FSIQ, PIQ, and VIQ were 94.5 (17.0), 95.4 (17.8), and 93.7 (17.6). VMI and GAC were 91.6 (16.2) and 89.7 (18.0). Outcomes were shifted to the left of population norms, with the proportion having IQ scores >1 SD (score 2 SD (score <70, expected 2.27%) below population norms being: 23.3% and 8.3%, 25% and 8.3%, and 21.7% and 11.7% respectively. For VMI and GAC these proportions were 25% and 8.3%, and 35% and 13.3%. There were few predictors of outcomes: for FSIQ, grade-IV encephalopathy [effect size -15, 95%CI -29,-1; p=0.03]; PIQ, grade-IV encephalopathy [effect size -16, 95%CI -31, -1; p=0.04], VIQ, grade-IV encephalopathy [effect size -17, 95%CI -31, -4; p=0.01], living-related donor [effect size 10, 95%CI 2, 18; p=0.02], and rejection in first 30d [effect size 9, 95%CI 0.5, 17; p=0.04]; and VMI, grade-IV encephalopathy [effect size -20, 95%CI -33, -7; p=0.002], and PELD at activation [effect size 0.5, 95%CI 0.2, 0.9; p=0.006]. Variables not associated with neurocognitive outcomes included: age at transplant, year of transplant, having any severe complication post-operatively, growth failure, and socioeconomic status. CONCLUSION Neurocognitive and functional outcomes after liver transplant at age <6 years are shifted to the left of population norms. Severe encephalopathy at transplant predicted a poorer outcome. More research is needed to determine risk factors for the over 3X higher prevalence of scores <70 compared to population norms.