COVID-19 prevalence and mortality in a large italian hemoglobinopathies cohort

Background: Data on SARS-CoV-2 infection in Hemoglobinopathies are still scarce and controversial. Since March 2020, we, as Italian Society for Thalassemia and Hemoglobinopathies (SITE), recommended close monitoring and set up an Italian survey to verify the impact of SARSCoV- 2 infection on patients with Hemoglobinopathies (EMO AER COVID-19 NCT04746066) among Italian Centers. Aims: To explore the hypothesis of an increased vulnerability of Hemoglobinopathies to SARS-COV2 infection. Methods: After SITE proposal and Ethics Committee approval, each participating Center entered data on a specific electronic Case Report Form (eCRF) (https://covid19.site-italia.org). Inclusion criteria included positive swab or serology and at least 15 days of follow-up from either the onset of symptoms or SARS-CoV2 positivity. This cut-off is updated to February 15, 2021. Results: Twenty-seven Centers that provide care to 6121 patients with Hemoglobinopathy (65% of the Italian population) recorded a total of 275 SARS-CoV2 infections (overall, prevalence 4.5%), in 191 transfusion- dependent thalassemia cases (TDT, prevalence 5.8%), 36 non-transfusion- dependent thalassemia (NTDT, prevalence 2.3%) and 48 sickle cell disease patients (SCD, prevalence 3.7%). Median age was 41 years (IQR: 30-48, range: 9 months-85 year). Twenty-eight patients (10 %) were pediatrics (median age: 6.5 years, IQR: 4-11). Most patients (72%) had comorbidities;134 (49%) had splenectomy or functional asplenia. We observed a broad spectrum of disease severity, ranging from no symptoms in 65 patients (24%) to multisystem organ failure and death in 5 patients: 2 TDT (age: 49 and 56 years), 1 NTDT (age: 45 years), 2 SCD (age: 57 years both). Overall, 56 (20%) patients required hospitalization, 12 in high-intensity care unit;10 required support by oxygen, 11 needed more intensive ventilation support with continuous positive airway pressure (CPAP), and 7 required intubation. Nine patients required ad hoc transfusion or more than scheduled. Two SCD patients of 9 and 20 months of age, respectively, recovered after a long and life-treating disease. One TDT patient experienced reinfection after 3 months from the first;one 30w-pregnant SCD woman developed COVID-19 without consequences for herself and the fetus. Overall clinical severity has been higher in SCD than in thalassemia patients. Summary/Conclusion: The prevalence of COVID-19 in Hemoglobinopathies apparently overlaps the general population (4.5% vs 4.6%), however, these patients are more strictly observed and we could postulate that the precautions suggested or self-applied by the patients were effective. The overall mortality is 1.8% vs 3.4% and the difference may be due to the younger age of patients with Hemoglobinopathies. Our data confirm the higher risk of severe disease and death in SCD.