COVID-19 infection and complications according to ABO blood group in the elderly: A population-based subcohort and meta-analysis.

BACKGROUND AND OBJECTIVES: It is reported that ABO antibodies have a role in COVID-19 infection and severity; however, ABO antibody titres vary with advanced age. The aim was to analyse the association between ABO blood group and risk of COVID-19 infection and complications in elderly patients, and to contrast this data with findings in the overall adult population. MATERIALS AND METHODS: A prospective cohort study of the Navarre (Spain) population aged ≥60 years and a meta-analysis of published studies including participants of ≥60 years were carried out. RESULTS: In the Navarre elderly population, a higher risk of COVID-19 infection was identified in the A versus non-A and O group and lower risk in O versus non-O, with no significant association between hospitalization, intensive care unit admission or mortality and any of the blood groups, results that coincide with those of the overall Navarre adult population. The meta-analyses using studies that included participants of ≥60 years demonstrated a higher risk of hospitalization and mortality in A versus non-A and a lower mortality risk with B versus non-B. Similar mortality results were found in the meta-analyses of the overall adult population. CONCLUSION: There are no relevant differences between the overall adult population and population aged ≥60 years in the risk of COVID-19 infection and severity according to ABO blood groups, suggesting that age-related changes in ABO would be of limited clinical significance.

Mass Switch From Intravenous to Subcutaneous Tocilizumab in Rheumatic Diseases During the SARS-COV-2 Pandemic.

BACKGROUND: With the arrival of the SARS-CoV-2 pandemic in 2020, it was proposed to make the change from intravenous (IV) tocilizumab (TCZ) to its subcutaneous formulation, in order to avoid rheumatological patients having to go to the day hospital and guarantee enough IV TCZ for those critical patients with COVID who needed it. The aim of this study was to describe the rate and reasons for switching back to IV TCZ from subcutaneous TCZ. METHODS: We included patients from the rheumatology service that were on treatment with IV TCZ in February 2020 and were followed up until March 2021. Patients that remained on subcutaneous TCZ were compared with those who switched back to IV TCZ (switch-back group). A subgroup analysis according to rheumatic disease was performed. RESULTS: Fifty-five patients switched to subcutaneous TCZ: 28 rheumatoid arthritis, 19 giant cell arteritis, 4 polymyalgia rheumatica, 2 juvenile idiopathic arthritis, and 2 systemic sclerosis. Seventeen patients switched back to IV TCZ due to ineffectiveness (n = 8), patient preference (n = 4), adverse events (n = 4), and difficulty with the SC administration route (n = 1). In the analysis by disease, 4 of 23 patients switched back to IV TCZ in giant cell arteritis/polymyalgia rheumatica group due to ineffectiveness (n = 2), injection site reaction (n = 1), or patient preference (n = 1). In rheumatoid arthritis group, 11 of 28 patients switched back to IV TCZ: ineffectiveness (n = 5), patient preference (n = 3), headache (n = 1), injection site reaction (n = 1), and due to difficulty with the SC administration route (n = 1). CONCLUSIONS: Mass switch from IV to subcutaneous TCZ during the SARS-CoV-2 pandemic has been safe, effective, and well tolerated after 1 year of follow-up.

Role of the AB0 blood group in COVID-19 infection and complications: A population-based study.

Since the beginning of the COVID-19 pandemic, the ABO blood group has been described as a possible biological marker of susceptibility for the disease. This study evaluates the role of ABO group on the risk of SARS-CoV-2 infection and related complications in a population-based cohort including 87,090 subjects from the Navarre population (Northern Spain) with no history of SARS-CoV-2 infection and with known ABO blood group, after one year of the pandemic (May 2020 - May 2021). The risk of infection, hospitalization, Intensive Care Unit (ICU) admission and death was analyzed using multivariate logistic regression, adjusting for possible confounding variables. A lower risk of infection was observed in group 0 vs non-0 groups [OR 0.94 (95 %CI 0.90-0.99)], a higher risk of infection in group A vs non-A groups [OR 1.09 (95 %CI 1.04-1.15)] and a higher risk of infection in group A vs group 0 [OR 1.08 (95CI 1.03-1.14)] (when the 4 groups are analyzed separately). No association was observed between blood groups and hospitalization, ICU admission, or death in SARS-CoV-2 infected subjects. Regarding the risk of SARS-CoV-2 infection, we observed a protective role of group O and a greater risk in the A group.