The impact of length and weight on survival after heart transplantation in children less than 24 months of age.

Adults, older children, and adolescent patients with a BMI categorized as overweight or obese have decreased survival after HTx. Anthropometric correlates of survival after HTx in infants have not been well defined. In a retrospective analysis of the UNOS registry, patients age 0-24 months were classified according to the WHO height-for-age and weight-for-age norms, as well as arbitrary BMI-for-age percentiles. Outcomes of 1-year survival, conditional long-term survival, and cause-specific mortality were examined. Infants with stunted growth according to the WHO definition had increased risks of early mortality, late mortality, and death due to graft failure after HTx. Secondary analysis of first-year survival demonstrated increased mortality in children who were underweight according to weight-for-age, but a survival disadvantage in the highest BMI-for-age category, likely due to short recumbent length leading to relatively high BMI values. Stunted growth relative to WHO standards predicts mortality following heart transplant in children less than 2 years of age. The association between post-transplant mortality and high BMI-for-age, as demonstrated in older cohorts, was observed in the infant cohort only due to stunting, and not due to overweight classification.