Time from kidney failure onset to transplantation and its impact on growth in pediatric patients.

BACKGROUND: In children with kidney failure, the longer the duration of dialysis the greater the impact on growth deficit, quality of life, and life expectancy. The aim of this research is to test whether there was a shortening of treatment time from kidney failure to transplantation in pediatric patients and whether this time interval impacted height.

METHODS: Observational retrospective cohort study from 2005 to 2018. The first outcome variable was time to transplantation in years, while the second was height/age standard deviation score (SDS) at transplantation. Cox regression models were used to analyze time from disease to transplantation and linear regression was employed to test the association of the year of kidney failure onset with height.

RESULTS: A total of 780 children were evaluated and 517 underwent kidney transplantation after a median time of 1.9 years (IQR = 1.0-4.0). The variables significantly associated with time to transplant were: year of kidney failure onset (HR = 1.07; 95% CI: 1.05-1.10; p < .001), age at kidney failure onset <12 years (HR = 0.59; 95% CI: 0.49-0.71; p < .001), living in different state as transplant center (HR = 0.63; 95% CI: 0.53-0.77; p < .001), and undergoing blood transfusion before transplantation (HR = 0.63; 95% CI: 0.53-0.75; p < .001). Regarding growth, for each 1-year increase in the epoch of kidney failure onset, a 0.05 SDS raise in height/age is expected (p < .001).

CONCLUSION: Children with recent kidney failure onset had significantly lower time to the outcome and this reduction was associated with a less severe growth deficit.