Emergency Department Quality of Care for Sickle Cell Disease in Ontario, Canada: A Population-Based Matched Cohort Study
Authors: Chan Derek , Kouyoumdjian Fiona , Athale Uma , Pendergrast Jacob , Verhovsek Madeleine 
Published: November 2020

Background: Acute vaso-occlusive crisis (VOC) in sickle cell disease (SCD) frequently leads patients to seek emergency department (ED) care. Whether or not health inequities exist, and their exact nature, is poorly understood in ED visits for SCD VOC within a universal publicly funded healthcare system. In this study, we aimed to address this knowledge gap by characterizing the landscape of ED care burden and quality indicators for SCD VOC management in the province of Ontario, Canada.
Methods: We used population-level health administrative data to identify patients with SCD in Ontario who presented to the ED with SCD VOC (ICD-10-CA code D57.0) from 2006 to 2018. We evaluated quality of care indicators in the ED for this population and compared these with a general population group matched by age, sex, neighbourhood income quintile, geography (forward sortation area) and date of ED visit (-15 to +15 days per visit) (35,370 ED visits; 27,195 patients).
Results: We identified 1,811 patients who presented to the ED with SCD VOC for a total of 13,123 ED visits over the study period. Of ED presentations, 40% were pediatric (&lt; 18 years), 47% were male and 99% lived in urban settings.
Compared to ED visits for the matched group, ED visits for SCD VOC had a significantly higher proportion of high acuity triage scores (CTAS 1 or 2) (74% vs 18%; p &lt; 0.001), shorter time to initial physician assessment (76 ± 82 vs 90 ± 86 minutes; mean ± SD, p &lt; 0.001), longer period of ED assessment and observation (432 ± 261 vs 212 ± 179 minutes; p &lt; 0.001), increased likelihood of hospital admission (62% vs 5%; p &lt; 0.001), longer duration of inpatient stay (5.2 ± 6.7 vs 4.0 ± 8.1 days; p &lt; 0.001), and higher rates of repeat ED visits within 30 days of ED discharge (0.57 ± 1.44 vs 0.26 ± 0.79 visits; p &lt; 0.001).
We found specific socio-demographic variables associated with a poorer quality of care in ED visits for SCD VOC, including patients who were adults, male, from a low-income neighbourhood, having a greater number of dependents, a higher neighbourhood level of material deprivation, from an ethnically-concentrated neighbourhood, and those who lived in a residentially unstable region. Bivariate analyses for clinically meaningful outcomes (defined as ED disposition, repeat ED visit within 30 days, length of hospital admission stay, and being among the highest user bracket of ED care) further revealed significant socio-demographic associations that validated the clinical relevance of these determinants underlying ED metric disparities found within the SCD cohort (Table 1).
In subgroup comparisons, we observed a significant difference in triage acuity scoring for adults compared with children with SCD VOC, with a 25% lower rate of high acuity triage score (CTAS 1 or 2) (66% vs 86%). We also found that despite a majority of adults with SCD VOC receiving these scores compared to those in the matched group (66% vs 18%), their mean times to initial physician assessment were not significantly different (90 ± 94 vs 91 ± 89 minutes), reflecting an average SCD VOC wait time longer than the clinical practice guideline recommendation of first dose analgesic within the first 60 minutes of ED arrival. Furthermore, we identified a negative correlation between poor ED metrics and patients with SCD who were highly dependent on ED care (defined as 4-9 or ≥ 10 ED visits for SCD VOC per year) at levels significantly above the matched comparative baseline.
Conclusions: Indicators of ED care for SCD largely reflect the clinical acuity and severity of VOC presentations in Ontario, Canada. However, significant disparities in the quality of care received and in clinical outcomes for specific subgroups of patients with SCD, including those most vulnerable within this patient population, raises concern from a health equity perspective.By leveraging this landscape of SCD ED care, future policy, clinical and research efforts must work to understand, address and close these gaps in order to achieve best and equitable care for all.

Disclosures
No relevant conflicts of interest to declare.