Factors associated with statural growth in pediatric kidney transplant recipients with focus on metabolic acidosis

We investigated factors associated with post-transplant growth in pediatric kidney transplant (KTx) recipients with a focus on plasma bicarbonate (HCO3 ) and estimated the effect of alkali treatment on growth. In this study of the CERTAIN Registry, data were collected up to 5 years post-transplant. Generalized Additive Mixed Models were applied to assess the association between post-transplant growth and covariates. A trial-emulation analysis was performed to estimate the causal effect of alkali supplementation on growth. We report on 2147 primary KTx recipients with a median age at KTx of 10.2 (IQR 5.1;14.3) years. No statistically significant association was found between growth and HCO3 (p = 0.21), but the shape of the estimated conditional association showed a decreasing estimated growth with increasing HCO3 . Glucocorticoid treatment and allograft rejection showed an inverse association with growth. Living donor KTx, glomerulopathy, recombinant growth hormone use, low height z-score at KTx, younger age, and higher eGFR were positively associated with growth. The trial-emulation analysis included patients at 30 days and 3, 6, and 9 months post-transplant with HCO3