Comparing the Impact of Adolescents and Young Adults with Sickle Cell Disease on Children's Hospitals In the United States
Authors: Dickerson Amanda , Klima Jennifer , Rhodes Melissa , O'Brien Sarah H. 
Published: October 2019

Abstract
Abstract 1507

Background:
In recent decades, child mortality in sickle cell disease (SCD) has drastically decreased. Consequently, there is a growing population of young adults with SCD. The period of transition from pediatric to adult care is a vulnerable time for patients with chronic disease, and patients with conditions such as cystic fibrosis and congenital heart disease may continue care in pediatric settings well into young adulthood. To explore the impact of transitioning SCD patients at 18 years versus 21 years on children's hospitals, we compared reasons for hospitalization and resulting charges in adolescents (13-17 years) and young adults (18-21 years) admitted from 2000-09.

Methods:
Data were obtained from 25 children's hospitals within the Pediatric Health Information System (PHIS), a large administrative database of freestanding children's hospitals. SCD patients were identified by ICD-9-CM primary or secondary diagnostic codes of 282.41-42 or 282.60-69. Demographics, length of stay, discharge status, principal payer, diagnoses, procedures, and charges were compared between age groups. Length of stay and charges were not normally distributed and therefore were analyzed using the Wilcoxon rank sum test. Categorical data were compared using chi square statistics.

Results:
We identified 25,371 admissions of adolescents (n=18,299) and young adults (n=7,072) with SCD from 2000-09, with young adults accounting for 28% of admissions. These admissions represent 4,247 unique patients (52% female) with a range of 1 to 119 admissions per patient (median=3). We identified substantial variety in age of transition to adult care among participating hospitals. Using the 90th percentile (p90) of patient age as a surrogate for transition, we identified the following ages of transition: 18 years (n=2 hospitals), 19 years (n=5), 20 years (n=11), 21 years (n=6), and 22 years (n=1). Reasons for hospitalization were similar between the two age groups, with no clinically significant differences in the frequency of common discharge diagnoses or procedures (Table). Young adults were not more likely to be transferred to other facilities for additional care. Complications of adult SCD such as nephropathy and pulmonary hypertension were rare, occurring in <2.5% of discharges. Although length of stay was similar between adolescents and young adults (median=4 days), young adults tended to incur higher charges (median +$1,314, p<0.001) and were more likely to be covered by public insurance. Deaths (0.2% of admissions) were notably rare and similar across age groups (p=0.7).

Discussion:
Current practice patterns of U.S. children's hospitals vary with regard to age of transition to adult care for patients with SCD. Although our study was limited to those patients cared for in children's hospitals, adolescents (13-17 years) and young adults (18-21 years) with SCD appear to be quite similar with regards to reasons for hospitalization, and mortality was extremely low in both cohorts. Further studies are needed to investigate whether extending the age of transition to 21 years as a national standard may decrease morbidity, improve health-related quality of life, and increase readiness for transition in young patients with SCD.

Disclosures:
No relevant conflicts of interest to declare.