Biomarker Analysis | Industry Spotlights & Insight Articles

Study Analyses Predictive Biomarkers for COVID-19 ICU Patient Mortality

The study from the Federal University of Paraíba, Brazil analyses a series of haematological, biochemical, and inflammatory factors all contribute to the mortality of COVID-19 patients in the ICU.

The pandemic that changed the world from 2020 to 2023 hospitalised many and sadly led to many excess deaths. The severity of COVID-19 was heterogeneous among different patient populations: with some developing mild and manageable symptoms and others admitted to intensive care units with severe respiratory symptoms.

Furthermore, we learned even more about the broad and varied clinical manifestations of the disease as more cases were reported and patients were tracked. Although most patients with COVID-19 presented with respiratory complications, the infection was also shown to affect the digestive, cardiovascular, renal, and neurological systems.

Over the course of the public health crisis, medical professionals identified the risk factors which were linked with patients developing more deadly forms of the disease. Deaths due to COVID-19 have been associated with a hyperinflammatory immune response, cytokine storm, and multiple organ failure.

A study published in Frontiers Immunology outlines how a group from the Federal University of Paraíba in João Pessoa, Brazil, identified biomarkers which were predictive of the outcomes of patients with severe COVID-19.

The study took place in 2021 and followed 60 ICU patients with severe COVID-19. 41.6% (25) of patients were discharged, and 58.4% (35) of patients sadly passed away. The patient cohort consisted of both male and female adult patients over 18 years of age. Their cases of COVID-19 were confirmed using reverse transcriptase polymerase chain reaction (RT-qPCR). All were positive for severe acute respiratory syndrome (SARS).

To look for biomarkers that correlate with mortality, the team collected data from the patients at different points during hospitalisation. These data included a ‘complete blood cell count’, biochemicals in the blood, coagulation markers, antibodies for SARS-CoV-2, and cytokine levels.

Biomarkers Newsletter Email Banner

Results

Clinical characteristics

Researchers noted a significant difference of 10 years in the median age of survivors (59) and non-survivors (69). Furthermore, patient weight and obesity was statistically significant in mortality (p= 0.0056, p= 0.0181 respectively), with heavier and obese patients being more likely to survive.

The paper goes on to describe these results as being consistent with the so-called ‘obesity paradox’, as obesity is correlated with admission to the ICU, but not correlated with death thereafter.

Vaccination was also highly correlated to survival (p= 0.0006): 34% of non-surviving patients were vaccinated while 80% of surviving patients were vaccinated. All patients that had received all three vaccinations survived.

Related:

COVID-19 prognostic biomarker levels

The study concludes that haematological, biochemical, and inflammatory factors all contribute to the mortality of COVID-19 patients in the ICU. They found increased levels of Lymphopenia, neutrophilia, and thrombocytopenia served as prognostic markers for poor outcome in these patients.

Furthermore, the biochemicals CRP, AST, creatinine, ferritin, AST, troponin I, urea, magnesium, and potassium served as prognostic markers and were all associated with patient mortality. Changes in the cytokines IL-10, CCL2, CXCL9, and CXCL10 serum levels were also associated with increased mortality in patients.

The paper says: “Thus, this study confirms the relationship between the various biomarkers evaluated in hospitalized patients with severe COVID-19 and their relationship with fatal COVID-19.”

The findings support the need for further investigation in discovering possible targets that could diminish the expression of these biomarkers to treat and control viral respiratory infections such as COVID-19.