101 - Outcomes in Children with Sickle Cell Disease and End Stage Kidney Disease in the USRDS Registry

Poster Number: 101
Publication Number: 101.138

Rima Zahr, University of Tennessee Health Science Center College of Medicine, Memphis, TN, United States; Jeffrey Lebensburger, University of Alabama at Birmingham, Birmingham, AL, United States; Jeffrey C. Winer, Le Bonheur Children's Hospital, Memphis, TN, United States

Background:
Sickle cell disease (SCD) is an inherited hematologic disorder that causes progressive damage in many organs, including the kidneys.  Kidney damage is commonly manifested as albuminuria early on in childhood. A subset of patients developing rapid decline in kidney function leading to progressive disease, chronic kidney disease (CKD), and further to end stage kidney disease (ESKD). The previously reported prevalence of SCD-ESKD in children is less than other etiologies, however ESKD remains a risk for premature death in individuals with SCD.  In the last twenty years childhood survival has improved with the advancement of supportive care and disease modifying therapies for SCD, however there remains an uncertainty in the prognosis of SCD-ESKD.

Objective:
We sought to evaluate the relative survival and time to transplant of patients with ESKD with and without SCD, after being matched for initial year of service, age, sex, race, and ethnicity.

 

Design/Methods:
Patients aged 21 and younger were identified from the USRDS.  Propensity matching was performed for year of initial ESKD service, age, sex, race and ethnicity between patients with SCD-ESKD and non-SCD-ESKD.  Demographics and initial therapy were compared between unmatched and matched groups using Chi-square or Fisher exact testing, as appropriate.  Kaplan-Meier survival curves were created for the matched groups comparing survival and time to transplant.

Results: There were 96 SCD patients diagnosed with ESKD from 1998-2017.  Children with SCD kidney disease on average develop ESKD later in life than patients with non-SCD related kidney disease (18.3 vs. 14.0, p< 0.001).  We identified similar rates of first ESKD modality type, hemodialysis, and pre-ESKD nephrology care for SCD-ESKD and matched non-SCD-ESKD patients.  Children with SCD-ESKD patients had higher rate of cerebrovascular disease than matched non-SCD-ESKD patients.  However, the mean survival time for children with SCD-ESKD patients was significantly shorter than non-SCD-ESKD patients (7.0 years vs. 12.4 years) and SCD patients experienced a longer mean time before receiving transplant (10.3 years vs. 5.6 years) when matched.
 Conclusion(s):  
While children with SCD-ESKD represent a small proportion of ESKD in the United States, these children represent a group at increased risk for increased mortality and a disparity in time to receiving a transplant. Future studies need to evaluate therapies to prevent progression of kidney disease in children with SCD as well as understand barriers to kidney transplantation.
 

Figure 1Figure 1. Comparison between year of service, age, sex, race, and ethnicity-matched patients with sickle-cell disease-related end-stage kidney disease (SCD-ESKD) and non-SCD-ESKD. A) Kaplan-Meier survival analysis and B) Kaplan-Meier time to transplant analysis