Epidemiologist CSL Behring, King of Prussia, PA, USA Elkridge, United States
Background: Sickle cell disease (SCD) is the most common inherited blood disorder in the US and leads to lifelong morbidity. Epidemiologic data on emergency department (ED) and hospital utilization for SCD are lacking.
Objectives: To describe baseline characteristics of patients with SCD presenting to the ED for SCD-related events, including VOC, stratified by those discharged from the ED (treat-and-release cohort) and those who progress to hospitalization (inpatient cohort).
Methods: Patients who had an ED visit with an ICD-10-CM diagnosis of SCD from 1/2019-11/2021 were identified (first qualifying ED visit termed the index date) in IQVIA PharMetrics Plus®, a US commercial claims database. Eligible patients were ≥1 year old, continuously enrolled for ≥180 days pre-index (baseline period), and had ≥2 confirmatory diagnosis codes for SCD within a 5-year pre-index period. Baseline characteristics were described stratified by the two cohorts.
Results: Of 2,782 SCD patients who presented to the ED, 1,946 (70%) were discharged and 836 (30%) progressed to hospitalization within 1 day. More patients in the inpatient cohort (60%) than in the treat-and-release cohort (33%) had a diagnosis of VOC at the ED visit. Out of the 1,144 patients with a VOC at the index ED visit, 504 (44%) progressed to hospitalization and the remainder (56%) were treated in the ED and released. In the treat-and-release and inpatient cohorts, patients were most often between 18-50 years old (61% and 58%), female (65% and 59%), located in the South (68% and 59%), and covered by commercial insurance (56% and 54%). The mean (interquartile range [IQR]) Charlson Comorbidity Index was 0.7 (0, 1) for the treat-and-release cohort and 0.9 (0, 1) for the inpatient cohort. For the treat-and-release and inpatient cohorts, important comorbidities included: chronic pain (27% and 32%), bacterial infections (7% both), hepatobiliary complications (3% and 7%), thromboses other than deep-vein thrombosis (5% and 7%), acute chest syndrome (2% and 3%), and acute renal failure (3% and 4%); important medications included: opioids (39% and 53%), antibiotics (44% both), and folate (18% and 26%). In the baseline period, the mean (IQR) number of hospitalizations was 0.2 (0, 0) and 0.5 (0, 0) and the mean (IQR) number of ED visits was 1.0 (0,1) and 0.7 (0,1) in the treat-and-release and inpatient cohorts, respectively.
Conclusions: In this study of SCD patients who presented to the ED for a SCD-related event, baseline characteristics were similar between those who were discharged and those who progressed to hospitalization, though history of hepatobiliary complications, prior opioid use, and VOC episodes at presentation to the ED were more common in patients who progressed to hospitalization.
