Comorbidities are risk factors for hospitalization and serious COVID-19 illness in children and adults with sickle cell disease

•Children with SCD with history of pain and renal and heart/lung comorbidities are at higher risk of worse COVID-19 outcomes.•Adults with SCD with history of pain are at higher risk of worse COVID-19 outcomes. [Display omitted] Patients with sickle cell disease (SCD) are at high risk of developing serious infections, therefore, understanding the impact that severe acute respiratory syndrome coronavirus 2 infection has on this population is important. We sought to identify factors associated with hospitalization and serious COVID-19 illness in children and adults with SCD.We established the international SECURE-SCD Registry to collect data on patients with SCD and COVID-19 illness. We used multivariable logistic models to estimate the independent effects of age, sex, genotype, hydroxyurea, and SCD-related and -nonrelated comorbidities on hospitalization, serious COVID-19 illness, and pain as a presenting symptom during COVID-19 illness. As of 23 March 2021, 750 COVID-19 illness cases in patients with SCD were reported to the registry. We identified history of pain (relative risk [RR], 2.15; P < .0001) and SCD heart/lung comorbidities (RR, 1.61; P = .0001) as risk factors for hospitalization in children. History of pain (RR, 1.78; P = .002) was also a risk factor for hospitalization in adults. Children with history of pain (RR, 3.09; P = .009), SCD heart/lung comorbidities (RR, 1.76; P = .03), and SCD renal comorbidities (RR, 3.67; P < .0001) and adults with history of pain (RR 1.94, P = .02) were at higher risk of developing serious COVID-19 illness. History of pain and SCD renal comorbidities also increased risk of pain during COVID-19 in children; history of pain, SCD heart/lung comorbidities, and female sex increased risk of pain during COVID-19 in adults. Hydroxyurea showed no effect on hospitalization and COVID-19 severity, but it lowered the risk of presenting with pain in adults during COVID-19.