P1447: mortality and clinical complications among patients with sickle cell disease with recurrent vaso-occlusive crises in italy

Topic: 26. Sickle cell disease Background: Sickle cell disease (SCD) is an inherited hemoglobinopathy characterized by the expression of abnormal sickle hemoglobin that leads to a variety of acute and chronic complications. SCD complications, driven by vaso-occlusion, hemolysis, and vasculopathy associated with the disease, lead to increased mortality. Vaso-occlusive crises (VOCs), a hallmark clinical feature of SCD, can cause debilitating pain and lead to additional organ complications. Aims: To describe the mortality and clinical complications among patients with SCD with recurrent VOCs in Italy. Methods: This longitudinal, retrospective cohort study utilized an administrative database of Italian local health units covering 12 million Italian national health service-health assisted individuals to identify patients with SCD from January 1, 2011, to February 1, 2019. Eligible patients with SCD were required to have ≥2 VOCs (i.e., SCD with crisis, priapism, splenic sequestration, or acute chest syndrome on an inpatient admission) per year in any 2 consecutive years during the eligibility period and be continuously enrolled for 1 year before and after their index date (second VOC in the second year of 2 consecutive years). Patients who had received a hematopoietic stem cell transplant were excluded from the analysis. The dataset does not contain emergency department information; thus, the frequency of VOCs is likely to be under-reported. Each patient was matched to 5 controls without disease by age, geographic area, gender, and index year. Patients and controls were followed from index until death, exiting the database, or end of study period (February 1, 2020), whichever occurred first. Demographics were assessed at index. Mortality (proportion of total population and rate [deaths per 100 person-years]) was summarized for patients with SCD with recurrent VOCs and matched controls, and a chi-squared test was used for significance testing (P<0.05) for mortality rate differences. Clinical complications (proportion of total population) were summarized descriptively during follow-up for patients with SCD with recurrent VOCs. Results: In total, 111 patients with SCD with recurrent VOCs met the inclusion criteria and were matched to 555 controls. The mean age of patients was 24.5 years, and 49.5% were male. Controls had similar demographics. Mortality proportion (Patients with SCD: 9/111 [8.1%] vs. controls: 13/555 [2.3%]) and rate per 100 person-years (1.6 vs. 0.42; P<0.001, respectively) were higher for patients with SCD with recurrent VOCs than for matched controls. The most prevalent complications in patients were chronic pain (17.1%), liver complications (13.5%), avascular necrosis (10.8%), and gallstones (10.8%). Summary/Conclusion: Patients with SCD with recurrent VOCs had significantly higher mortality than matched controls. Despite the best available care, patients with SCD with recurrent VOCs continue to experience significant SCD-related clinical complications, highlighting the need for innovative therapies in this space. Keywords: Hemoglobinopathy, Mortality, Complications, Sickle cell disease