Case Fatality Rate and Severity of COVID-19 among Patients with Sickle Cell Disease: A Systematic Review and Meta-Analysis

The sickle cell disease (SCD) population has been considered particularly vulnerable to viral pandemics since the emergence of H1N1 in 2009. In this sense, the advance of the COVID-19 pandemic from 2020 has brought this group of patients to the center of concern. However, scientific knowledge about the susceptibility of patients with SCD to a severe COVID-19 pandemic is still insufficient, and efforts to establish a general profile of the disease in these patients, remain inadequate. The present study, therefore, sought to characterize the case fatality rate and severity of COVID-19 in patients with SCD throughout the world. A systematic review of Pubmed/MEDLINE, Scopus, Cochrane Library, and Virtual Health Library databases through December 2021 was then performed. Subsequently, the primary and secondary outcomes were used in the meta-analysis in RStudio (R) software. Seventy-two studies were included with 6,011 SCD patients confirmed to have SARS-CoV-2 infection between mid-2020 and early 2022. The mean age of patients was 27 years. During this period, 218 deaths caused by COVID-19 were reported in the studied population, corresponding to an overall case fatality rate of 3%. In addition, 10% of patients with SCD were admitted to the ICU after complications caused by COVID-19, and 4% of them required invasive ventilatory support. In conclusion, the high fatality rate, intensive care unit admission and need for mechanical ventilation due to COVID-19 in young patients with SCD indicate that this population is at high risk for severe disease progression.