Introduction: Marked muscle wasting (MMW) impacts 40% of adult liver transplant patients and increases post-liver transplant mortality risk, but less is known in pediatrics. This study evaluated the prevalence and age distribution of MMW in a nationally representative cohort of pediatric liver transplant registrants and the association between MMW and long-term survival.

Method: MMW status was documented by the Organ Procurement and Transplantation Network (OPTN) at transplant candidate registration between 1994 and 2004. MMW was clinically assessed and categorically distinguished as: yes, no, or unsure. Using the OPTN Standard Transplant Analysis and Research dataset, we applied descriptive statistics and conducted an unadjusted survival analysis across all years of follow up.

Results: Among 9,074 registrants, 51% were female and mean age was 5.01 years. Median follow-up was 26.13 years (IQR 23.64-28.68) with 150,621.41 person-years of observation. For MMW classification, 1531 (16.8%) had MMW, 6761 (74.5%) had no MMW, and 782 (8.6%) had unsure MMW. Mean age for those with MMW was 3.59 years, those with no MMW was 5.40 years, and those with unsure MMW was 4.40 years. This analysis found no significant differences in long-term survival rates when comparing outcomes by MMW status (p-value = 0.39).

Conclusion: MMW affected 1 in 6 children waitlisted for liver transplant with a mean age of 3.59 years. Given the known relationship between MMW and mortality among adults, results suggest subjective measures are inadequate and support the need to identify feasible, objective measures of MMW for pediatric pre-transplant assessment.