ABSTRACT
Background : The increasing COVID-19 cases and rising scientific
interest on the role of ABO blood type in disease susceptibility and
outcomes highlight the need to explore the associations among Filipinos,
cognizant of racial and genetic predisposition. This study determined
the relative risk of COVID-19 infection and disease outcomes with ABO
blood type among Filipino patients.
Methods : Employing an ambispective cohort, 550
consecutively-selected, hospitalized Filipino adult patients with
SARS-CoV-2 RT-PCR result were included. Medical records of previously
admitted patients were retrospectively reviewed and pertinent data were
extracted. Prospectively, patients who were still admitted were
recruited and followed-up. Risk ratio estimated the risk of primary
(COVID-19 infection and severity) and secondary outcomes (ICU admission,
intubation, and mortality).
Findings : The risk of COVID-19 infection was 20% higher among
type A (aRR=1·20, p =0·021) but was 19% lower among type O
(aRR=0·84, p =0·023). Blood type A (aRR=1·25, p =0·041) was
25% at greater risk for severe-to-critical COVID-19 infection, while
moderate COVID-19 was 62% higher among type AB (aRR=1·62,p =0.037) and was 54% lower among type O (aOR=0·65,p =0·010). ABO blood type did not predict any disease outcomes.
Interpretation : ABO
blood type was an independent predictor of COVID-19 infection and
severity but not disease outcomes. Type A has higher risk for COVID-19
infection and severe-to-critical COVID-19, while type O had lower risk.
This information can be utilized in identifying the population-at-risk,
developing programs and interventions, increasing vigilance in medical
management, and promoting adherence to precautionary and protective
health-seeking behaviors.
Funding : Philippine Council for Health Research and Development