ERN-EUROBLOODNET EUROPEAN REGISTRY OF PATIENTS AFFECTED BY RED BLOOD CELL DISORDERS AND COVID-19

ABSTRACT

Background: Patients with red blood cell disorders (RBCD), are likely to be at increased risk of complications from SARS-Co-2 (Coid-19), but eidence in this population is scarce due to its low frequency and heterogeneous distribution. Aims: ERN-EuroBloodNet, the European Reference Network in rare hematological disorders, established a European registry to determine the impact of COVID-19 on RBCD patients and identify risk factors predicting seere outcomes. Methods: The ERN-EuroBloodNet registry was established in March 2020 by VHIR based on Redcap software in accordance with the Regulation (EU) 2016/679 on personal data. The local Research Ethics Committee confirmed that the exceptional case of the pandemic justifies the waier of informed consent. Eligible patients had confirmed RBCD and COVID-19. Data collected included demographics, diagnosis, comorbidities, treatments, and COVID-19 symptoms and management. For analysis of COVID-19 seerity, two groups were established 1) Mild asymptomatic or mild symptoms without clinical pneumonia and 2) Seere pneumonia requiring oxygen/respiratory support and/or admission to intensie care unit. Continuous ariables were compared using the Wilcoxon rank-sum test or Kruskall Wallis test, while categorical ariables were analyzed using the Chi-square test or Fisher's Exact test. Releant factors influencing disease or seerity were examined by the logistic regression adjusted for age. Results: As of February 25, 2022, 42 medical centers from 10 EU countries had registered 428 patients 212 Sickle cell disease (SCD), 186 Thalassemia major and intermedia (THAL). The mean age of SCD was lower (22y) than of THAL (39.4y). Splenectomy and comorbidities were higher in THAL (51.4% and 61,3%) than in SCD (16,3% and 46,8%) (p<0.001, p=0.004). Age and BMI correlated with COVID-19 seerity, as described in the general population (p=0.003, p<0.001). Fig 1 shows age distribution and COVID-19 seerity by disease seerity groups. The mean age for seere COVID-19 was lower in patients with seere SCD (SS/SB0 s SC/SB+ 23y s 67.5y) and THAL (major s intermedia 43.5 s 51.3y) (p<0.001). Potential risk factors such as eleated ferritin, current chelation or history of splenectomy did not confer additional risk for deeloping seere COVID-19 in any patient group. Only diabetes as a comorbidity correlated with seerity grade in SCD (p=0.01) and hypertension in THAL (p=0.009). While seere COVID-19 infection in SCD was associated with both ACS (p<0.001) and kidney failure requiring treatment (p<0.001), this was not predicted by a history of preious ACS or kidney disease in steady state. Oerall, 14,6% RBC patients needed oxygen/respiratory support, 4% were admitted to ICU with an oerall mortality rate of 1%, much lower than reported in other similar cohorts. Hospital Son Espases, Palma de Mallorca, Spain;54 Clinical Pharmacology Serice, Hospital Uniersitari Vall d'Hebron, Barcelona, Spain;55 Vall d'Hebron Institut de Recerca, Barcelona, Spain;56 Diision of Hematology and Oncology, Department of Internal Medicine, American Uniersity of Beirut Medical Center, Beirut, Lebanon;57 UOC Pediatric Hematology Oncology, Uniersity of Padoa, Padoa, Italy;58 Department of Haematology, Oxford Uniersity Hospitals NHS Foundation Trust, Oxford, United Kingdom;59 Translational Research in Child and Adolescent Cancer, Vall d'Hebron Institut de Recerca, Barcelona, Spain Background: Patients with red blood cell disorders (RBCD), are likely to be at increased risk of complications from SARS-Co-2 (Coid-19), but eidence in this population is scarce due to its low frequency and heterogeneous distribution. Aims: ERN-EuroBloodNet, the European Reference Network in rare hematological disorders, established a European registry to determine the impact of COVID-19 on RBCD patients and identify risk factors predicting seere outcomes. Methods: The ERN-EuroBloodNet registry was established in March 2020 by VHIR based on Redcap software in accordance with the Regulation (EU) 2016/679 on personal data. The local Research Ethics Committee confirm d that the exceptional case of the pandemic justifies the waier of informed consent. Eligible patients had confirmed RBCD and COVID-19. Data collected included demographics, diagnosis, comorbidities, treatments, and COVID-19 symptoms and management. For analysis of COVID-19 seerity, two groups were established 1) Mild asymptomatic or mild symptoms without clinical pneumonia and 2) Seere pneumonia requiring oxygen/respiratory support and/or admission to intensie care unit. Continuous ariables were compared using the Wilcoxon rank-sum test or Kruskall Wallis test, while categorical ariables were analyzed using the Chi-square test or Fisher's Exact test. Releant factors influencing disease or seerity were examined by the logistic regression adjusted for age. Results: As of February 25, 2022, 42 medical centers from 10 EU countries had registered 428 patients 212 Sickle cell disease (SCD), 186 Thalassemia major and intermedia (THAL). The mean age of SCD was lower (22y) than of THAL (39.4y). Splenectomy and comorbidities were higher in THAL (51.4% and 61,3%) than in SCD (16,3% and 46,8%) (p<0.001, p=0.004). Age and BMI correlated with COVID-19 seerity, as described in the general population (p=0.003, p<0.001). Fig 1 shows age distribution and COVID-19 seerity by disease seerity groups. The mean age for seere COVID-19 was lower in patients with seere SCD (SS/SB0 s SC/SB+ 23y s 67.5y) and THAL (major s intermedia 43.5 s 51.3y) (p<0.001). Potential risk factors such as eleated ferritin, current chelation or history of splenectomy did not confer additional risk for deeloping seere COVID-19 in any patient group. Only diabetes as a comorbidity correlated with seerity grade in SCD (p=0.01) and hypertension in THAL (p=0.009). While seere COVID-19 infection in SCD was associated with both ACS (p<0.001) and kidney failure requiring treatment (p<0.001), this was not predicted by a history of preious ACS or kidney disease in steady state. Oerall, 14,6% RBC patients needed oxygen/respiratory support, 4% were admitted to ICU with an oerall mortality rate of 1%, much lower than reported in other similar cohorts. Summary/Conclusion: Results obtained so far show that seere COVID-19 occurs at younger ages in more aggressie forms of SCD and THAL. Current preentie approaches focus on age oer disease seerity. Our data highlights the risk of seere COVID-19 infection in some young patients, particularly those with SS/SB0 SCD, suggesting that immunization should be considered in this pediatric group as well. Results between similar sized cohorts of RBCD patients ary between each other and those presented here, highlighting the importance of collecting all of these small cohorts together to ensure adequate statistical power so that definitie risk factors can be reliably identified and used to guide management of patients with these rare disorders in the light of the ongoing pandemic. (Figure Presented).