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ABO blood group as a determinant of COVID-19 and Long COVID: An observational, longitudinal, large study
Joan B Soriano1,2,3, Adrián Peláez1,2,3, Xavier Busquets4
1Servicio de Neumología, Hospital Universitario de la Princesa, Madrid, Spain.
Insights
This study found no link between ABO blood groups and COVID-19 severity or developing Long COVID. Blood type distribution in patients with acute or Long COVID matched general population frequencies, showing no significant associations.
Area of Science:
- Immunology
- Epidemiology
- Genetics
Background:
- The association between ABO blood groups and susceptibility or severity of COVID-19 has been a subject of ongoing research and debate.
- Previous studies have yielded conflicting results regarding the potential influence of blood type on COVID-19 outcomes, including the development of Long COVID.
- Understanding these associations could inform public health strategies and patient risk stratification.
Purpose of the Study:
- To investigate the distribution of ABO blood groups in patients hospitalized with acute COVID-19.
- To examine the ABO blood group distribution in patients experiencing Long COVID.
- To determine if specific ABO blood subgroups are associated with an increased risk of developing Long COVID.
Main Methods:
- Observational study adhering to STROBE guidelines.
- Analysis of ABO blood group distribution in cohorts of acute COVID-19 and Long COVID patients.
- Statistical analysis using contingency tables and Mantle-Haentzel odds ratios (OR) with 95% confidence intervals (CI), adjusted for age, sex, ethnicity, and acute COVID-19 severity.
Main Results:
- The ABO blood group distribution among 1,513 acute COVID-19 patients (43.2% O, 45.6% A, 7.5% B, 3.8% AB) mirrored expected general population frequencies.
- Among 135 Long COVID patients, the ABO distribution (44.4% O, 45.2% A, 6.7% B, 3.7% AB) showed no significant difference compared to the acute COVID-19 cohort (p ≥ 0.843).
- Multivariate analysis revealed no significant association between ABO blood subgroups (A, AB, B) or Rh factor and the development of Long COVID.
Conclusions:
- This study found no statistically significant association between ABO blood group subgroups and the risk of developing COVID-19 or Long COVID.
- The observed blood group distributions in both acute and Long COVID patient cohorts align with general population frequencies.
- Further research may be warranted, but current findings do not support blood type as a predictive factor for COVID-19 outcomes or Long COVID.
Background:
An association of ABO blood group and COVID-19 remains controversial.
Methods:
Following STROBE guidance for observational research, we explored the distribution of ABO blood group in patients hospitalized for acute COVID-19 and in those with Long COVID. Contingency tables were made and risk factors were explored using crude and adjusted Mantle-Haentzel odds ratios (OR and 95% CI).
Results:
Up to September 2022, there were a total of 5,832 acute COVID-19 hospitalizations in our hospital, corresponding to 5,503 individual patients, of whom blood group determination was available for 1,513 (27.5%). Their distribution by ABO was: 653 (43.2%) group 0, 690 (45.6%) A, 113 (7.5%) B, and 57 (3.8%) AB, which corresponds to the expected frequencies in the general population. In parallel, of 676 patients with Long COVID, blood group determination was available for 135 (20.0%). Their distribution was: 60 (44.4%) from group 0, 61 (45.2%) A, 9 (6.7%) B, and 5 (3.7%) AB. The distribution of the ABO system of Long COVID patients did not show significant differences with respect to that of the total group (p ≥ 0.843). In a multivariate analysis adjusting for age, sex, ethnicity, and severity of acute COVID-19 infection, subgroups A, AB, and B were not significantly associated with developing Long COVID with an OR of 1.015 [0.669-1.541], 1.327 [0.490-3.594] and 0.965 [0.453-2.058], respectively. The effect of the Rh+ factor was also not significant 1,423 [0.772-2,622] regarding Long COVID.
Conclusions:
No association of any ABO blood subgroup with COVID-19 or developing Long COVID was identified.
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