Early erythropoietin therapy is associated with improved growth in children with chronic kidney disease

Recent registry reports related short stature at the time of dialysis initiation to increased morbidity and mortality. Growth may therefore serve as an overall indicator of disease severity and therapy quality in pediatric chronic kidney disease. We studied whether early correction of uremic complications such as anemia was associated with growth failure. In this retrospective cohort study, we assessed demographic, diagnostic, and therapeutic variables at first referral and at dialysis initiation in all children with congenital renal diseases who initiated chronic dialysis at our clinic between 1994-2004. Outcomes were indicators of growth at referral and first dialysis as well as interval growth. Correlation and logistic regression techniques were used for analysis. We studied 47 children (24 boys, 23 girls) who were 7.1 years of age and had a mean glomerular filtration rate (GFR) of 25 ml/min per 1.73 m(2) at first visit. Time to dialysis was a median 2.5 years. At first referral, 36% of children had severe growth failure with standard deviation score (SDS) height < -2. Stature at that time point was correlated with GFR (rho=0.37, p=0.03) and predicted stature at dialysis initiation (rho=0.81, p<0.001). Catch-up growth during predialysis care was achieved in 40% of the children and independently associated with both hemoglobin (OR=1.85, p=0.04) and erythropoietin therapy (OR=13.6, p<0.05) at first referral. This study confirms the disappointingly high prevalence of growth retardation in children with chronic kidney disease. Initial hemoglobin and early erythropoietin prescription were the only (modifiable) variables associated with improved growth. Almost two thirds of referred children, however, experienced no catch-up growth during follow-up. Further study is needed to better define the optimal timing and intensity of nephrologist care in children with kidney disease.