Susceptibility of β-Thalassemia Heterozygotes to COVID-19

Background: β-Thalassemia is the most prevalent single gene blood disorder, while the assessment of its susceptibility to coronavirus disease 2019 (COVID-19) warrants it a pressing biomedical priority.

Methods: We studied 255 positive COVID-19 participants unvaccinated against severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2), consecutively recruited during the last trimester of 2020. Patient characteristics including age, sex, current smoking status, atrial fibrillation, chronic respiratory disease, coronary disease, diabetes, neoplasia, hyperlipidemia, hypertension, and β-thalassemia heterozygosity were assessed for COVID-19 severity, length of hospitalization, intensive care unit (ICU) admission and mortality from COVID-19.

Results: We assessed patient characteristics associated with clinical symptoms, ICU admission, and mortality from COVID-19. In multivariate analysis, severe-critical COVID-19 was strongly associated with male sex (p = 0.023), increased age (p < 0.001), and β-thalassemia heterozygosity (p = 0.002, OR = 2.89). Regarding the requirement for ICU care, in multivariate analysis there was a statistically significant association with hypertension (p = 0.001, OR = 5.12), while β-thalassemia heterozygosity had no effect (p = 0.508, OR = 1.33). Mortality was linked to male sex (p = 0.036, OR = 2.09), increased age (p < 0.001) and β-thalassemia heterozygosity (p = 0.010, OR = 2.79) in multivariate analysis. It is worth noting that hyperlipidemia reduced mortality from COVID-19 (p = 0.008, OR = 0.38). No statistically significant association of current smoking status with patient characteristics studied was observed.

Conclusions: Our pilot observations indicate enhanced mortality of β-thalassemia heterozygotes from COVID-19.