Clinical characteristics of COVID-19 patients in ABO blood groups

BACKGROUND AND AIM: Coronavirus Disease 2019 (COVID-19) is a novel respiratory infection caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Recent studies have suggested that certain blood groups may be associated with different risks of COVID-19 infection and mortality. METHODS: We conducted a retrospective case-control study to determine if ABO blood groups are associated with different clinical outcomes. Our study involved 286 COVID-19 patients. RESULTS: We found that patients with the AB blood group had a higher risk of COVID-19 compared to the control group (OR=3.63, 95% CI=2.76-4.76, p<0.0001). Conversely, patients with the O blood group had a higher risk of death (OR=9.56, 95% CI=3.059-27.89, p=0.001). White blood cell (WBC) counts, C-reactive protein (CRP) levels, and the Neutrophil to Lymphocyte ratio (NLR) varied among ABO blood groups. Comparing fatal to survival cases, we observed that fatal cases had higher levels of WBC, CRP, and NLR in comparison to survivors. Multiple logistic regression analysis revealed that age, O blood group, and NLR were independent factors for mortality. CONCLUSIONS: ABO blood groups can exhibit different clinical characteristics. Nonetheless, it is crucial to emphasize that elevated inflammation markers and advanced age are also independent risk factors for mortality. Further studies with larger populations are essential to fully comprehend the relationship between ABO blood groups and COVID-19 outcomes.