Introduction and objective:
In COVID-19, the rapid prediction of the severity of a patient’s condition using modern biomarkers can accelerate the implementation of appropriate therapy, and thus improve the patient’s prognosis.

Material and methods:
A meta-analysis was conducted of data available in the literature on the differences in baseline suPAR blood concentration between patients (1) who tested positive and negative for COVID-19, (2) who had severe and non-severe COVID-19, and (3) COVID-19 survivors and non-survivors.

SuPAR levels in SARS-CoV-2 negative and positive patients varied and amounted to 3.61±1.59 ng/ml vs. 6.45±3.13 ng/ml, respectively (MD = -3.18; 95%CI: -4.71 to -1.66; p<0.001). suPAR levels among non-severe and severe COVID-19 patients were 7.06±2.64 ng/ml and 5.06±3.16 ng/ml (MD = 0.18; 95%CI: -2.48 to 2.83; p=0.90), respectively. Pooled analysis showed that suPAR levels between severe versus critical COVID-19 patients to be 5.59±1.54 ng/ml and 6.49±1.43 ng/ml, respectively (MD = -1.00; 95%CI: -1.31 to -0.70; p<0.001). The suPAR levels between ICU survivors versus non-survivors amounted to 5.82±2.33 ng/ml and 8.43±4.66 ng/ml (MD = -3.59; 95%CI: -6.19 to -1.00; p=0.007). In the case of in-hospital mortality, the mean suPAR level among survivors to hospital discharge was 5.63±1.27 ng/ml, compared to 7.85±2.61 ng/ml for patients who did not survive (MD = -3.58; 95%CI: -5.42 to -1.74; p<0.001).

SuPAR levels are significantly elevated in severe COVID-19 illness and maybe useful in predicting mortality. Further studies are needed to determine cut-off points and clarify the association of suPAR levels with disease progression. This is of utmost importance given the ongoing pandemic and overburdened health care systems.

The study was supported by the ERC Research Net and by the Polish Society of Disaster Medicine.
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