¿Qué factor predice mejor el pronóstico en pacientes con COVID-19: los biomarcadores analíticos o la relación PaO2/FiO2?

Abstract

Background

The study aimed to describe patient characteristics and outcomes by PaO₂/FiO₂ (PAFI) and degree of inflammation.

Methods

Retrospective cohort study with data on patients collected from March 1^st, 2020 to March 1^st,2023, from the Spanish SEMI-COVID-19 Registry. Non-nosocomial patients with data on PAFI (<100 vs. 100-200 vs. 200-300 vs. >300) who received corticosteroids (CS) for COVID-19 in the first 48 h of admission were included in the study. 5,314 patients met the inclusion criteria for the present study. The primary outcome was in-hospital mortality.

Results

Higher in-hospital mortality was found in the groups with PAFI< 100 (51.5% vs. 41.2% vs. 25.8% vs. 12.3%, P<.001). They also required more NIMV, IMV, and ICU admission, and had longer hospital stays. Those patients with PAFI>300 and 4-5 high-risk criteria presented higher mortality than the patients with PAFI 200-300 and only 1-2 criteria of analytical inflammation. Risk factors associated with higher in-hospital mortality were age (OR = 1.06; 1.05-1.06), moderate (OR = 1.87; 1.49-2.33) and severe (OR = 2.64; 1.96-3.55) degree of dependency, dyslipidemia (OR = 1.20; 1.03-1.39), higher Charlson index (OR = 1.19; 1.14-1.24), tachypnea on admission (2.23; 1.91-2.61), the higher number of high-risk criteria on admission, and lower PAFI on admission. Female gender (OR = 0.77; 0.65-0.90) and the use of RDSV (OR = 0.72; 0.56-0.93) were found to be protective factors.

Conclusions

The lower the PAFI and the higher the degree of inflammation in COVID-19, the higher the in-hospital mortality. Inflammatory escalation precedes respiratory deterioration and should serve as an early predictor of severity to deciding the use of anti-inflammatory/immunosuppressive therapy.