Risk factors for increased ED utilization in a multinational cohort of children with sickle cell disease

The objective was to identify clinical, social, and environmental risk factors for increased emergency department (ED) use in children with sickle cell disease (SCD).

This study was a secondary analysis of ED utilization data from the international multicenter Silent Cerebral Infarct Transfusion (SIT) trial. Between December 2004 and June 2010, baseline demographic, clinical, and laboratory data were collected from children with SCD participating in the trial. The primary outcome was the frequency of ED visits for pain. A secondary outcome was the frequency of ED visits for acute chest syndrome.

The sample included 985 children from the United States, Canada, England, and France, for a total of 2,955 patient-years of data. There were 0.74 ED visits for pain per patient-year. A past medical history of asthma was associated with an increased risk of ED utilization for both pain (rate ratio [RR] = 1.28, 95% confidence interval [CI] = 1.04 to 1.58) and acute chest syndrome (RR = 1.60, 95% CI = 1.03 to 2.49). Exposure to environmental tobacco smoke in the home was associated with 73% more ED visits for acute chest syndrome (RR = 1.73, 95% CI = 1.09 to 2.74). Each $10,000 increase in household income was associated with 5% fewer ED visits for pain (RR = 0.95, 95% CI = 0.91 to 1.00, p = 0.05). The association between low income and ED utilization was not significantly different in the United States versus countries with universal health care (p = 0.51).

Asthma and exposure to environmental tobacco smoke are potentially modifiable risk factors for greater ED use in children with SCD. Low income is associated with greater ED use for SCD pain in countries with and without universal health care.