Mortality and Clinical Complications Among Patients with Sickle Cell Disease with Recurrent Vaso-Occlusive Crises in France

OBJECTIVES: Sickle cell disease (SCD) is an inherited hemoglobinopathy characterized by abnormal sickled hemoglobin that can lead to vaso-occlusive crises (VOCs), significant morbidity, and early mortality despite availability of current treatment options. This study describes the mortality and clinical complications in patients with SCD with recurrent VOCs in France.

METHODS: This longitudinal, retrospective cohort study utilized the French National Health Data System database (SNDS, système national des données de santé). Patients were identified by having an inpatient claim or registration in the long-term condition database (ALD, affection longue durée) with a diagnosis of SCD between January 1, 2012, and March 1, 2019. Eligible patients with SCD were required to have ≥2 VOCs/year in any 2 consecutive years. Patients were required to have ≥1 year of data before and after their index date (i.e., the second VOC in the second consecutive year). Patients were followed from index until death or study period end (March 1, 2020). Demographics were assessed at index. Mortality (proportion of population, rate [deaths per 100 person-years], and mean age of death) and clinical complications (proportion of population) were summarized descriptively during follow-up.

RESULTS: In total, 4,602 patients with SCD with recurrent VOCs were included. The mean age of patients was 19.8 years, 51.8% of whom were female. Mean length of follow-up was 4.4 years. Patients experienced an average of 3.8 VOCs per patient per year. In total, 101 (2.2%) patients died during follow-up. Mortality rate was 0.64 deaths per 100 person-years. Mean age of death was 39.3 years. The most prevalent clinical complications were anemia/leukocytosis (44.1%), infections (42.0%), multi-organ failure (38.2%), chronic pain (26.6%), and gallbladder disease (17.8%).

CONCLUSIONS: Despite available care, patients with SCD with recurrent VOCs experience significant SCD-related clinical complications and increased mortality risk, highlighting the need for innovative therapies for these patients.